tbonner1
Headphoneus Supremus
- Joined
- Mar 13, 2002
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REVIEW AND COMPARISON OF 21 HOME HEADPHONE AMPS
Thanks to Skylab for his great review of portables, I though I should contribute and offer my feedback for home amps. I will just put the reviews up front so you can get to the rankings. Test methodology is discussed at the end.
Here is a reference with links put together by m8o for most of the currently available home amps listed in this comparison:
http://www.head-fi.org/forums/showth...03#post2350581
RANKINGS
1-Bada PH-12
2-Doge 6210
3-Singlepower PPX3 6SN7
4-Yarland P-100
5-ASL MG Head MKIII
6-Presonus Central Station
7-Little Dot III+
8-G&W 2.6F
9-Feel/OK2000 HP-100A
10-Little Dot II+
11-Little Dot II
12-M3
13-PPA
14-Xtra X-1
15-Ming Da
16-Xiang Sheng 708B
17-Pioneer A-35R
18-Pimeta
19-Marantz 2230
20-Enhanced CMOY
21-Cmoy
Yarland P100
Skylab has performed a comprehensive review that I think is very accurate here with hi-rez pictures:
http://www.head-fi.org/forums/showth...hlight=Yarland
But the purpose of this review is to compare the Yarland P100 and rank it relative to other home amplifiers.
BACKGROUND
As you can see from the rankings, the Bada PH-12 is the reference amp so far out of the units tested. Although it may not be the very best in every category, it is still the unit to beat in this comparison. The more I listen to the Bada and compare it with other amps, the more convinced I am of its virtues. Usually, the more I listen to a component the more flaws I find. Subsequently, I focus on elements I find subtractive to the music. This is not the case with the Bada. I have been content with it as my main headphone amp as other headphone amps and headphones come and go. The Bada is not the tubiest sounding amp and perhaps this is one of the reasons I find its flaws minimally subtractive to the music. It also drives the AKG 701 with ease.
Thanks to Headfiers who asked to add the Yarland P-100 to this comparison test. The Yarland fits the profile as another high valued Chinese built tube amp. I got mine from STO Sound and Vision
http://www.tsto.com/cgi-bin/TSTO.sto...duct/View/2554
an actual brick and mortar store located in Jenkintown, PA. I like the idea of supporting real businesses that provide ongoing customer service rather than websites that we have seen come and go out of business in a short period of time. I dealt with the president, Mike Leshner, who was very helpful, and subsequently referred me to Dave Garrison who is the Yarland product specialist. I spoke with Dave over the phone who was very knowledgeable regarding the P-100 technical specifics as well as providing information about the company.
Yarland also manufactures several high value tube speaker amplifiers along with the Yarland P-100, so this is not an orphan product from a boutique company. I agree with Skylab’s review that the Yarland P-100 looks like a more expensive piece of gear. The wood front panel is a nice variation, the tiffany style RCA jacks are audiophile approved as it the large machined aluminum knobs (if you look at the electronic parts sites, large machined knobs by Kilo can cost up to $30+ each).
http://www.alliedelec.com/Catalog/In...0&N=4294933331
If you have struggled with trying finding obscure tubes for some of the Chinese amps, you will be pleased to find the Yarland uses the ubiquitous and respected EL84 output tubes along with 6N3 input tubes. Both types are easy to find on Ebay and tube websites as well and are inexpensive (read $10-$20 each is the median price). These tubes can also be found newly manufactured so you are not confined to search for vintage 40+ year old tubes.
COMPARISONS
I got rid of the stock tubes are tried several different combinations. The best I tried were the Electro Harmonix EL84, the Russian 6P14P (ER and EV) for output. I settled on the Russian 6N3 and Bendix 2C51 for input. I did not have the GE 5670’s that Skylab had but will try them soon. There was a big improvement with the upgraded tubes over the stock units. The EH EL84’s were particularly smooth and lacking any trace of harshness.
The Yarland with the EH EL84’s had a classic tube smoothness in the midrange and treble where the Bada PH-12 tended to have more of a solid state sound. The Bada had better bass slam and the bass dug deeper. The Bada had better dynamic range and did not sound congested during complex music passages. I am finding that many amps seem to not be as problematic with midrange and treble. It is the lack of problems with bass, congestion during complex music passages( in general, most solid state amps have faster rise time and slewing ability) and dynamics that seem to elevate the top amps from the rest of the pack.
The Doge 6210 retains more of the traditional pure tube lushness, when compared to the Bada, in the midrange and treble. The Doge uses different 12AX7 input tube types than the Yarland’s 6N3 but they both use the same respected EL 84 output tubes. I wish we could listen to exactly the same tubes on both the Yarland and Doge. Then we would be able to compare the sound differences of the amps themselves rather than the sound of different tubes. With the upgraded tubes on both amps, bass from the Doge sounded more full with the hard to drive AKG 701. The tight sound of the Yarland’s bass complimented the Senn 650’s. Many complain the bass is a bit overpowering on the Senn’s and interferes with the midrange. The Yarland provided a balanced sound with the Senn 650’s and this was my favorite headphone match.
The Yarland also did well with most of the IEM’s I tried. I get hum through the Bada (I know the reason it hums: Because it doesn’t know the words…sorry) with most of the IEM’s I tried. I would not recommend the Bada if I was interested in driving IEM’s.
The Yarland comes with a 300-ohm outlet that worked well with the Senn 650’s. There is a 32-ohm outlet that worked best with IEM’s such as the Shure E500 and the new Future Sonics M5. Many complain of the Senn 650’s as a bit bass heavy and the Future Sonics M5’s have a similar sonic signature. I have not found many tube home amps that sound good with IEM’s but the Yarland really made the Future Sonics sing and they sounded as good as I have heard them.
The Yarland had a bit better detail than the ASL MG Head MKIII. The ASL in OTL mode and the Senn 650’s results in one of my favorite combinations for providing great soundstage. But the definition is just too much better on the Yarland, and ultimately more accurate to the source. The macro definition along with the ability to drive IEM’s pushed the Yarland’s rank above the ASL. It is a close call near the top of the rankings and I can see how some would prefer the ASL for it’s lush soundstage if you used Senn 650’s.
Treble
Smooth and tube dependent. The amp allows the sonic character of the tube to flow. You would be surprised how many amps restrict this. I think simply getting out of the way and allowing the sound of the tube to flow is one of the most important characteristics of any tube amp.
Midrange
Same as above. As you roll tubes what you will hear is more the difference between the tubes and not the amplifier. This is what many tube lovers strive for and is a sonic trait of the best amps.
Bass
Not the deepest and lacking the impact of the best but has good pitch control and avoids the one-note bass of many tube amps.
Image
Open and smooth presentation without a hiked up treble presence.
Dynamics
Good with the Senn 650, Future Sonics M5, Shure E500 and other IEM’s tried. Not as good with the AKG 701’s.
Yarland P-100 vs. Bada PH-12: Winner-Bada PH-12
Doge 6210
(most of the other amps have pictures posted with their reviews, but I can post pictures for other amps if you would like)
I find myself largely in agreement with drartherwells review here:
http://www.head-fi.org/forums/showth...highlight=doge
I did not want to like this amp. I was very happy with the Bada PH-12 and thought it would be almost impossible to beat. It took a long while to find an amp I liked as much as the Bada; one I could just relax and stop listening to equipment and just enjoy the music. I was “sold” on the idea of the Bada’s hybrid design. My thought was that the hybrid design would ameliorate two often-quoted problems I consistently heard with tube amps:
1-Speed (and subsequent micro detail) not as good as solid state
2-Bass on tube amps not as tight or deep as solid state
I tried to keep an open mind regarding all tube amps and I am glad I did. Regarding my two above listed reservations:
1-The Doge is detailed
2-Bass is very deep. It also is taught and natural on a level with solid state amps without the bass bloat I have heard with other all tube amps.
If you think the AKG 701’s are bass-lite you need to hear them with this amp. I do hear a difference between the Odeum and General settings with General having a wider soundstage. The build quality has not been discussed much and I find it to be well built, but the aluminum panel finish and lettering on my unit are not up to the Bada’s level if I was to nit pick. Parts are typical higher level Chinese but you will not find any Black Gates or Solen parts in here. The front panel is very thick brushed aluminum with a heavy overhead bar that allows you to move the amp like a tool box….a nice touch I have not seen elsewhere. The amp runs cool, which is a big plus toward preserving the life of internal parts in my book. The knobs are aluminum not silver colored over plastic as on some others. If they cut costs on the knobs it makes me worry about where else they may have cut costs. The power output is .5 watt which is a bit lower than what I would like to see, but this amp seems to no problem driving the AKG’s and the Senn’s with headroom to spare.
The Doge just gets out of the way and allows the sound of the tubes to flow through. It is hard to choose favorites at this high level. The quantitative differences at this level frequently amount to the differences in sound of cables, which is small. At this level, you may be listening to the differences in the tube types (i.e. 6922’s, 6SN7’s etc.) and subsequent brands selected by the designer rather than the sound of the amp itself. There are fans for different tube types just as there are for different opamps with solid state gear. Many long-term tube rollers seem to prefer the 6SN7’s used in the Bada and they may be right. But I worry about the heat that may wear down the internal parts of the Bada. And you do have to be careful with the mosfets on the Bada. The Doge does seem to have a bit more homogenous and even presentation, perhaps because it is all tube. This one is very close. The Bada has slightly better macro definition and transient attack compared to the sublime Doge presentation. To quote a famous review “There is more “”There”” there” with the Bada.
Treble
Sparkles without calling too much attention to itself. Lots of air around instruments and voice if it is in the recording.
Midrange
Good micro detail and not overly rich or tubey. Just right.
Bass
The best I have heard from an all tube design
Image
Not pinpoint precise as some solid state amps can be.
Dynamics
Among the best for all tube design. Does not sound congested during complex music passages.
Doge 6210 vs. Bada PH-12: Winner-The Bada by a hair
Xtra X1
I know, it is a portable not a home amp. But I thought it might be instructive to see how this competes as many people ask how a portable compares to a home amp. I refer people to Skylabs great portable amp comparison for more details:
http://www.head-fi.org/forums/showth...t=portable+amp
This amp may have been the biggest surprise in this entire comparison at how good it sounded and how well it compared to the home amps. As good as the Xtra X1 sounded; it was not rated as high as some of the other portables in Skylabs portable comparison. I have heard a Hornet (with an unimpressive MP3 source) and a few other portables but could not compare them for the purpose of this test. The Bada winning this particular shootout was not a surprise, but the margin of victory was not as big as you would think. On some efficient IEM’s like the UE Super Fi 5 Pro’s the Xtra was quieter than the Bada at low listening levels.
I am cringing in pain as I write this in anticipation of the flames from folks who think these tiny portables cannot sound this good driving full-sized headphone. If you think this new generation of portable amps sound is improved please comment, as there will be many home amp lovers who disagree.
Treble
Clean with surprisingly good shimmer on cymbals. Much improved over the older opamp based portables that could sound like water drops on a hot radiator.
Midrange
Once again, clear without the old opamp coldness.
Bass
Not the deepest or the most impact but surprisingly good.
Image
Lacking the air that you find in home amps. Imaging is a weak point.
Dynamics
Amazing power and punch even when compared to a home amp.
Xtra X1 vs. Bada PH-12: Winner-The Bada
Presonus Central Station
Ferbose’s updated review:
http://www.head-fi.org/forums/showth...entral+Station
and the original with help from Music Man:
http://www.head-fi.org/forums/showth...entral+Station
I admit to being biased towards tube sound. My wife is a classically trained musician and I like rock, so we go to a diverse mix of live concerts from the symphony to jazz and hard rock. Tube amps just sound more like music to me for all genres particularly classical and jazz. With rock it becomes harder to choose. However, I know many musicians with home studios that swear that solid state gives them a better window into the music that is being recorded.
I was biased against the Central Station when I saw it had an opamp based headphone amp, and the opamp was not that highly regarded. But a musician
http://www.fishertheband.com/
and producer
http://www.ronw.com/studio.html
who I trust had one in his home studio so I gave it a try. I was wrong, this is a great sounding headamp. It goes to show you that parts alone do not determine the final sound quality. With all the other features such as switching flexibility, great DAC and state of the art preamp, this unit is a steal at the price. But this is only a ranking for the headphone amp.
The Central Station does almost nothing wrong. I could very happily live with it’s clean sound mated alongside rich sounding headphones like the Senn’s. The Senn’s do not really need the richness most tubes impart, but still sound surprisingly good with many tube amps. But times are good for us headphone lovers and there is a seductive quality to music played through any of the top tube amps that is tough to beat once you are used to it.
Treble
Clear but lacking the air around the intruments that comes with tubes. The decay is not as well done.
Midrange
As above
Bass
Taught and deep. I was surprised to get deep bass out of my Shure E4C.
Image
Precise and a strong point of high end solid state
Dynamics
Good punch and plenty of power.
Presonus Central Station vs. Bada PH-12: Winner-The Bada PH-12
SinglePower PPX3
I borrowed this amp because I wanted to see how it sounded before I bought one as it was a bit more expensive. This is the non-Slam version with Solen upgrade and the 6SN7 tubes that I like. SinglePower and Ray Samuels have a very loyal following for good reason.
-Both have a reputation well deserved for reference standard, almost super human support and service. This is remarkable considering how finicky and difficult to please we headphone people are.
-Both use expensive high quality audiophile approved parts from start to finish. You will not see cost cutting by committee with these folks.
Many of the Chinese companies are hiding under the desk feigning communication problems when it comes to offer post sales service and support. They don’t get it and do not believe that lack of service will diminish point of sale decisions. When weighed against the added cost of providing Class A support, they would rather have a few less sales to fussy audiophiles.
But this is a tough field and we are ranking products by sound quality so I will try to be objective. I am putting on my nomex asbestos flame suit for this one because of all the loyal followers of SinglePower on this forum.
The chassis is not overbuilt and the quality of parts used is very high. I will cut to the chase and say the PPX3 6SN7 was a top sounding amp. It did not have the last bit of micro detail and dynamics on this example. I was hoping for more bang for the buck, but the Chinese offer intense competition at this price point.
Treble
Smooth and rich. You can easily hear the differences between lean tubes and rich tubes with this amp…a good sign.
Midrange
Same as above.
Bass
Good texture but lacking some impact.
Image
Images float well and sound open
Dynamics
Just a bit off
SinglePower PPX3 6SN7 vs. Bada PH-12: Winner-The Bada PH-12
Bada PH-12
Here is one of the original reviews for the Bada:
http://www.head-fi.org/forums/showth...highlight=Bada
And an alternate view:
http://www.head-fi.org/forums/showth...highlight=Bada
Much has been said about this amp, but it offers great definition for the money. I caution every Bada owner to wait 24 hours before you remove any tubes. It you remove tubes before the current dissipates your will blow the delicate Toshiba mosfets. The fix is easy, but just wait and be safe. This design begs for some type of bleeder resistors and I am looking into doing this without compromising the sound. You get Solen and Rubycon audiophile grade parts in this amp and 1 watt of power. It may be the extra power of the Bada over all tube amps that provide the extra bit of macro dynamics that I prefer.
The fit and finish on the Bada PH-12 is quite good. The amp is heavy with a nice brushed aluminum top panel and black clear front panel that lets the LED’s shine through. Many seasoned users feel the (vintage NOS) 6SN7 tubes used with the Bada are the best for driving headphones over other tube types.
Here is a quick test: On the SACD version (or the redbook version which is still very good) of Miles Davis-Kind of Blue you can hear the extra bite the Bada has on horns and in the critical midrange. Most tube amps smooth this texture and you do not hear the bite that is there when listening to live instruments. On Diane Krall-Love Scenes track #7 “I Don’t Stand a Ghost of a Chance with You” (an audiophile reference recording) see if you can hear changes in the mix (including tape hiss) as her voice stops and starts. The Bada does not smooth out the sound of female vocalists and gets the acoustic bass notes being plucked just right.
Caution: I have not got the best sound from the Bada with sensitive IEM’s like the UE Super Fi 5 Pro’s and I did not care for the Grado’s with this amp.
Treble
Very detailed but lacking some of the natural smoothness of all tube designs.
Midrange
Good definition
Bass
Solid to the lowest octave with good impact
Image
Pinpoint precise without the diffuse image on some tube amps.
Dynamics
Powerful and a reference standard
Bada PH-12 vs. ASL MG Head MKIII: Winner-The Bada PH-12
G&W 2.6F
A nicely designed and built amp. This is another hybrid design that I am biased to like. But unlike the hot running Feel and the hotter flame throwing heat from the Bada, the G&W has a nice large external heat sink that runs cool to the touch without need for a fan. The G&W also runs mosfets with tubes, in this case a pair of 6922 types.
This is a solid amp with good drive that does very little wrong. It sounds quiet with IEM’s and drives low and high impedance headphones well. We are reaching a high level and the detail and air of the G&W fall short of the ASL.
Treble
Lacks the shimmer and sheen on cymbals of the best tube amps.
Midrange
Vocals and acoustic instruments lack air.
Bass
Deep and solid.
Image
Sounds more solid state than tube.
Dynamics
Plenty of power.
G&W 2.6F vs. ASL MG Head MK III:Winner-ASL MG Head MKIII
Little Dot III+
Sword Yang’s (Little Dot’s designer) attempt to upgrade the entry LD II+. This is an ambitious design:
-Solid and vented chassis solves the heat problem of the LD II+
-Heavy duty isolated power supply
-Switch selectable triode or pentode mode
-Auto detecting headphone impedance circuit
-Ability to drive speakers through rear binding posts
-Upgraded parts including Wima, Vishay, Nichicon ALP Blue Velvet volume pot
With all of this my hopes were high as I really liked the LD II and II+. One thing I noticed was the LD III+ solved the congestion problem mentioned with the LD II+. This amp has rhythm and pace even when pushed.
However, one aspect working against the LD III+ was a slight lack of transparency compared to the LD II+. Perhaps this is due to the more simple and direct circuit path the LD II+. I suspect that the additional auto-impedance detection circuit may be a cause for the reduction of transparency. It does work well and I have not seen this feature on any other design. I did not have a schematic for the III+, but did want to get one in order to experiment with disabling/removing the board that senses headphone impedance and suspect that may clean up the sound a bit.
Treble
Smooth but lacking air
Midrange
Same as above
Bass
Good impact and deep in Triode and Pentode mode
Image
Wide and deep
Dynamics
Good overhead without the congestion noted in entry LD amps
Little Dot III+ vs. ASL MG Head MK III:Winner-ASL MG Head MKIII
ASL MG Head MKIII
This design has evolved over the years (along with the price which is now $500) and has improved. You have a switch to toggle from OTL and transformer coupled mode. This was a mod suggested quite a while ago on an older version in these forums and I wonder if the importer took note. In OTL mode the sound with the Senns is one of my favorites: lush and very musical. This amp lacks a bit of the micro detail of the very best, but makes up for it by presenting such an open window on the music you don’t miss it. It also runs cool and is quiet without the hum problems of earlier units. With this amp we are approaching the top tier.
Treble
Rich with good decay.
Midrange
Very realistic without being hyper detailed.
Bass
Not the tightest, but good texture.
Image
Wide and deep, a strongpoint.
Dynamics
Surprisingly good with the Senns even in low power OTL mode.
ASL MG Head MK III vs. Feel HP-100A: Winner ASL MG Head MKIII
Ming Da 66
The Ming Da is well built with heavy power supply. A robust power supply at the top of my list and helps determine how much the manufacturer has invested in producing good sound. The parts quality and wiring also was of good quality. I have had Ming Da integrated tube amps that sound good and similar to my Cayin/Prima Luna amp. Everything seemed in place.
This amp lacked the air, detail and definition of other tube amps. One of the methods I use to determine this is listening to how the amp responds to tube rolling with top respected tubes. With top amps, you should be able to clearly hear the difference between tube changes as you do with opamps. The Ming Da exhibited a muffled sound that you had to listen through to discern tube differences. I am biased toward tubes but this amp does not squeeze out the most detailed sound in a tube. It was also noisy and did not do well driving sensitive IEM’s.
Treble
Smooth and tubey, a bit rolled off.
Midrange
Richly defined .
Bass
Not tight and bloated. An example of tube bass looseness.
Image
Wide but diffuse lacking specificity.
Dynamics
Hard to determine due to the bass overhang.
Ming Da 66 vs. Feel 100: Winner-Feel HP-100A
Xiang Sheng 708B
Not the best build quality on this amp, but the price is low. The chassis is thin stamped steel, PCBs are thin (we like military specification boards) and the ALPS labeled volume pot looks like a “copy” (AKA knockoff). The tube in the front opening is for display only and does nothing but act as a nightlight as far as I can tell. We are not off to a good start and this is not what I would call a robust design.
Stock, I preferred the LD II+ in terms of build quality and sound. The Xiang was a bit harsh with the stock tubes and it sounded more congested than the LD II+ did when pushed. The Xiang sounded better with high impedance headphones and had trouble with inefficient headphones.
However, as noted in the extensive mod thread for the Xiang
http://www.head-fi.org/forums/showth...ht=xiang+sheng
this amp is easy to work on and can be modded. The tubes are relatively easy to find and you can make improvements in the sound just by upgrading the tubes alone. I had problems with the volume pot not tracking equally on both channels. But this amp does show improvements with tube rolling that can clearly be heard, perhaps due in part to it’s simple basic design. I like modifying FM tuners and this amp reminds me of a stock Kenwood KT 7500. It is an easy to work on, is a 5 gang tuner that does not sound great stock, but the aggregate improvement from several key mods (opamp, power supply, filters etc.) improve this to a world class tuner.
Treble
Harsh with stock tubes.
Midrange
Congested during complex music passages.
Bass
Not the deepest.
Image
A bit bloated and not well defined.
Dynamics
Lacking punch.
Xiang Sheng 708B vs. Feel 100: Winner-Feel HP-100A
Little Dot II+
Price creep becoming an issue as the price went up to $145. However, you get smoother Mullard tubes on the front end that are easier to find and roll. However, you also get preamp outputs, which worked well.
http://www.head-fi.org/forums/showth...&highlight=dot
Controversy about tube arching hurt the reputation of this amp after I wrote the above review. I think much of this was due to a bad batch of the 4P1S power tubes. The good news is that you can order replacements from Little Dot. But other sources for this tube or finding different branded versions of the 4P1S have proven difficult at best. Some have argued that the problem was not merely a bad batch of tubes and point to subsequent modifications in the new version of the amp to support that point. My analysis is that there was a bad batch of 4P1S tubes. Subsequent modifications were made to help prevent arching in the event of future defective tubes (such as bleeder resistors) but I believe the cause of the arching can be traced to bad tubes. Replacement tubes were sent out at no charge and the customer service from David (the Ebay seller) and Sword Yang (the designer) was first class despite the bargain basement price of the amp.
The following is taken from the above listed review.
Treble
The LD II+ has a different presentation and is not as bright as the LD II. The LD II+ has a smoother high end with longer decay.
Midrange
Richer than the LDII.
Bass
A bit more full and sounds closer to typical tube amplifier bass.
Image
Slightly improved depth of soundstage, width is about equal. It sounds less solid state and more tube like.
Dynamics
More rounded presentation is less congested with better delineation during complex dynamic passages.
Little Dot II+ vs. the Feel: Winner-Feel HP-100A
Little Dot II
When these first came out the price was around $95 plus shipping. A replacement set of 4 new tubes was and additional $15.
My original review is here:
http://www.head-fi.org/forums/showth...&highlight=dot
Please note my comment regarding congestion during complex music passages with this amp. Despite the heat issue, this amp allows an entry to tube sound for users who might not ever consider it.
The following is taken from the above listed review.
Treble
Shimmering cymbals with very musical decay
Midrange
Lush and life like, but lacking the last bit of detail of the very best tube amps.
Bass
Full with great impact. Not as tightly detailed and lacking the pitch and speed of the best.
Image
Great soundstage but does not have the pinpoint precision of the best solid state designs.
Dynamics
A strength of this design. If you are used to similarly priced opamp units in this price range you will be pleasantly surprised by the improvement.
This is comparison is close but the congestion issue hurt the LD II. If not for the congestion, I might give preference to the LD II.
Little Dot II vs. the Feel: Winner-Feel HP-100A
Pioneer A35 Integrated amp
I would like to find a well-built integrated amp that also has a good headphone amp with a functional preamp and switching capabilities. I had a Fisher 400 tube receiver that was pretty good at also driving high impedance headphones. Why is it hard to find a mainstream speaker amp with an audiophile level headphone amp that utilizes the same chassis and heavy power supply? A few years ago Creek had an integrated amp that also had a nice headphone amp built in but it was expensive. I have heard the Portal Panache. It sounded clean, but I have not compared it directly to a headphone amp.
The Pioneer is not bad, but I would still not give up my dedicated headphone amp.
Treble
Quiet, but I can hear the grain with low impedance headphones.
Midrange
Not the last word in definition.
Bass
Full but lacking detail.
Image
I lost interest for critical listening.
Dynamics
Strong with high impedance headphones.
Pioneer A35R vs. the Feel: Winner-Feel HP-100A
Marantz 2230
The amp section on the receiver is similar to the amp of the Marantz 1060. Mkmelt (and others) has posted that this amp has a decent headphone port for high impedance headphones. You should budget money to replace the caps and have the unit serviced because these units are 30 plus years old. The tuner is not good on these, but the phono preamp is good. I had mine upgraded with Panasonic FM caps
Treble
Can sound overly smooth with little transient response.
Midrange
Smooth and tubey sounding.
Bass
The bass was full but lacking definition.
Image
Hard to tell due to overall lack of definition.
Dynamics
With a full size power supply, there was dynamic range and a lack of congestion.
Marantz 2230 vs. the Feel: Winner-Feel HP-100A
Rockhopper M3
I liked doing business with Rockhopper, but when I last checked he has stopped building amps. I have heard versions of this amp that sounded different with different parts, more than other amps I have compared with different configurations. This amp had 8610 opamps that I preferred with the Senns and Elpac “wall wart”. The amp can be improved with better power supplies.
Treble
Not a lot of air or sparkle and somewhat recessed.
Midrange
Rich and clean but prominent in the mix.
Bass
Solid and strong.
Image
Lack of air hinders the presentation and depth.
Dynamics
Good with Elpac, better with improved power supply and audiophile caps.
M3 vs. the Feel: Winner-Feel HP-100A
Feel/OK 2000 HP-100A Hybrid
This caught my attention as what looked like an incredible bargain. The build quality, case and features were similar to the $1000 plus Headroom amps at the time, yet this cost around $200. The Feel used 6922 tubes with a mosfet output. This combination of tube low level preamplification combined with solid state output was first brought to my attention by the Absolute Sound editor Harry Pearson in 1976. His reference system was the Audio Research SP 3A tube preamp and solid state GAS Ampzilla amplifier and I had this set up for a while and the soundstage sounded incredible. I went to the Soundcraftsman preamp because it had a 10 band equalizer and patching features I needed for field recording along with clean solid state sound, but the SP3A sounded more like music.
The Feel ran very hot despite heavy external heatsinks. It has an input select switch for 2 inputs. It sounded closer to solid state than tube.
Treble
Smooth but lacking some air at the top.
Midrange
Clean but not as smooth as an all tube amp.
Bass
No tube bloat here
Image
A bit diffuse but better than the PPA
Dynamics
Good punch
Feel 100 vs. the PPA: Winner-Feel HP-100A
PPA
This was the version 1 without the diamond buffers and with an Elpac. This was considered one of the better DIY amps when there was not much to choose from in the $300 range only a few years ago. Still a clean sounding amp.
Treble
Sharp and clear
Midrange
Clear
Bass
Tight and lean and a good match with the Senns. Not as full sounding as the M3.
Image
Precise but not wide or with depth
Dynamics
Improved over CMOY and Pimeta
PPA vs. Pimeta:Winner-PPA
Enhanced CMOY
An upgrade of the original design with a socketed 2134 opamp and audiophile parts.
Sounds similar to the original CMOY but the signature can be voiced by changing the opamp
Enhanced CMOY vs. Pimeta Winner-Pimeta
Pimeta
When this design first came out they were touted as an improvement over the CMOY.
Treble
Fast attack, little decay
Midrange
Clean but lacking tone body
Bass
Punchy, but with little deep bass
Image
2D
Dynamics
Limited
Pimeta vs. CMOY:Winner-Pimeta
CMOY
One of the first in a wave of DIY designs
Simple design that took advantage of a wave of clean sounding audio opamps capable of driving headphones.
Clean sounding but cold and sterile presentation
Treble
Clear, a strength of this simple and clean design
Midrange
Same as above
Bass
Taught but not deep
Image
A bit flat and newer designs made big improvements
Dynamics
Limited
First amp: CMOY
BACKGROUND
I started my headphone search back in the 70’s, and I am surprised at how little headphone and tube amp technology has changed since that time. My system consisted of many Absolute Sound recommended components:
Headphones
Koss Pro 4AA, Sennheiser HD 414, AKG 240, Stax SRD-7 with Stax SRX MKII.
Speakers
Dahlquist DQ-10
Electronics
GAS Ampzilla amplifier
Soundcraftsman PE 2217 preamplifier
Source
Thorens 125, 126
Technics SP-10
SME tonearm non-detachable head
Grace 707
Marantz 120
Revox A-700 half track
Tandberg 10X-D
At the time, when I “upgraded” to the Stax system they cost as much as used car (for a college student on a budget). I was very disappointed in the lack of bass impact and cold sounding midrange. None of the headphones had the depth and image of a pair of properly set speakers like the Dahlquists. If this was (among) the best headphone sound available I would prefer to listen to speakers.
Over the years I tried various flavor of the month headphones but they did not compare to the sound of speakers. Only recently, I started critical listening with headphone amps. JMT designs (Anyone remember him? Great guy.) were popular and I tried some of his amps. They were around $150-$300 with a good power supply and the best parts in models like the Pimeta. With the Senn 580 or Grados they showed promise.
SYSTEM
Headphones
AKG 701
Grado 225
Grado 80
Senn 650
Senn 580
Koss Portapro
Koss KSC 75
Koss KSC 35
Shure E4C
UE Super Fi 5 Pro
Altec IM 716
JVC FX-33 Marshmellows
Panasonic HJE-50
Senn MX 500
Speakers
JM Labs Cobalt 820
Acoustic Research AR-9
AER Pisces V.2
Several 8 and 10 subwoofers
Sound Dynamics RTS-3
Electronics
Cayin TA-30/Prima Luna tube integrated amp
Aragon 2004 MKII solid state power amp
Aragon 24 preamp
Acurus DIA 100 integrated amp
Belkin Power filter
Monster Power filter
Source
Sony SACD 333ES CD player
Rotel 991 CD player for HDCD
Technics A10 DVD-A player
Presonus Central Station DAC
Philips DVP-642 transport
McIntosh MR 67 tuner
Acuphase T100 tuner
Vinyl reluctantly given away
METHODOLOGY
Regarding test methodology: I have tried to test the same source connected to the Aragon 24 preamp, a passive switchbox, and now the Central Station. I then connected 2 headphone outputs to a simple “Y” junction box I cobbled together with 2 of these Xin suggested cables:
http://www.radioshack.com/product/in...entPage=search
and SPDT toggle switches on each input so I can switch one off and then the other on to a single headphone output. I found this extra cable blunted the transients a bit but it did enable instant A-B comparisons. I did most of my listening with the most simple connection of source to headphone amp and then to the headphones. I used the Rotel 991 via the analog output (for HDCD that I like) and with the Presonus DAC (for redbook only), Sony SCD 333ES for SACD (my favorite) and the Technics A-10 for DVD-A. I used the Silver Audio Silver Bullet 4.0 with silver WBT connectors as an interconnect. I also used a Monster 1000A Power Filter and the Belkin Pure AV PF30 filter with different power cables. The stock cables were used with the AKG 701,Senn 650 and 580. Level matching is absolutely critical and hard to get right.
I used the tubes and opamps that came with the amps for the purpose of this review. Most of the stock tubes supplied with these amps are not the best and many refer to them as “throw aways” or worse, and I agree. However, in an effort to be consistent and avoid tube preference arguescussions I had to base these reviews on the original configurations.
I am not affiliated with any of the above companies. I am not an employee of any of the above companies or vendors. I do not own stock in any of the above companies nor do any of my relatives that I know of.
I am open to any ideas and comments regarding how to improve these comparisons and this format.
EPILOGUE
I worked at a software test lab for years. When the explosion of video games started, we were contracted by Disney, Sony Studios and others to test game software. I found the project managers for the game software to be brilliant, innovative and among the best in the business. I suspect the designers for the new wave of portables are also at the leading edge of design and this is where the energy and talent is focused for headphone amps. This is not surprising, as I have read that vendors in China report they sell 10 portable headphone amps for each home amp sold.
My preconceived notion that opamp based headphone amps could not sound as good as tubes has been challenged by amps such as the Presonus Central Station. I still prefer tube amps. However the gap is closing.
DOCUMENT UPDATES
3/12/07-030507homeampreview original document
3/12/07-030507homeampreview1 grammar change
3/13/07-030507homeampreview2 added CMOY info, added Feel pics, add opamp detail, added epilogue
5/24/07 added Yarland P-100
Thanks to Skylab for his great review of portables, I though I should contribute and offer my feedback for home amps. I will just put the reviews up front so you can get to the rankings. Test methodology is discussed at the end.
Here is a reference with links put together by m8o for most of the currently available home amps listed in this comparison:
http://www.head-fi.org/forums/showth...03#post2350581
RANKINGS
1-Bada PH-12
2-Doge 6210
3-Singlepower PPX3 6SN7
4-Yarland P-100
5-ASL MG Head MKIII
6-Presonus Central Station
7-Little Dot III+
8-G&W 2.6F
9-Feel/OK2000 HP-100A
10-Little Dot II+
11-Little Dot II
12-M3
13-PPA
14-Xtra X-1
15-Ming Da
16-Xiang Sheng 708B
17-Pioneer A-35R
18-Pimeta
19-Marantz 2230
20-Enhanced CMOY
21-Cmoy
Yarland P100
Skylab has performed a comprehensive review that I think is very accurate here with hi-rez pictures:
http://www.head-fi.org/forums/showth...hlight=Yarland
But the purpose of this review is to compare the Yarland P100 and rank it relative to other home amplifiers.
BACKGROUND
As you can see from the rankings, the Bada PH-12 is the reference amp so far out of the units tested. Although it may not be the very best in every category, it is still the unit to beat in this comparison. The more I listen to the Bada and compare it with other amps, the more convinced I am of its virtues. Usually, the more I listen to a component the more flaws I find. Subsequently, I focus on elements I find subtractive to the music. This is not the case with the Bada. I have been content with it as my main headphone amp as other headphone amps and headphones come and go. The Bada is not the tubiest sounding amp and perhaps this is one of the reasons I find its flaws minimally subtractive to the music. It also drives the AKG 701 with ease.
Thanks to Headfiers who asked to add the Yarland P-100 to this comparison test. The Yarland fits the profile as another high valued Chinese built tube amp. I got mine from STO Sound and Vision
http://www.tsto.com/cgi-bin/TSTO.sto...duct/View/2554
an actual brick and mortar store located in Jenkintown, PA. I like the idea of supporting real businesses that provide ongoing customer service rather than websites that we have seen come and go out of business in a short period of time. I dealt with the president, Mike Leshner, who was very helpful, and subsequently referred me to Dave Garrison who is the Yarland product specialist. I spoke with Dave over the phone who was very knowledgeable regarding the P-100 technical specifics as well as providing information about the company.
Yarland also manufactures several high value tube speaker amplifiers along with the Yarland P-100, so this is not an orphan product from a boutique company. I agree with Skylab’s review that the Yarland P-100 looks like a more expensive piece of gear. The wood front panel is a nice variation, the tiffany style RCA jacks are audiophile approved as it the large machined aluminum knobs (if you look at the electronic parts sites, large machined knobs by Kilo can cost up to $30+ each).
http://www.alliedelec.com/Catalog/In...0&N=4294933331
If you have struggled with trying finding obscure tubes for some of the Chinese amps, you will be pleased to find the Yarland uses the ubiquitous and respected EL84 output tubes along with 6N3 input tubes. Both types are easy to find on Ebay and tube websites as well and are inexpensive (read $10-$20 each is the median price). These tubes can also be found newly manufactured so you are not confined to search for vintage 40+ year old tubes.
COMPARISONS
I got rid of the stock tubes are tried several different combinations. The best I tried were the Electro Harmonix EL84, the Russian 6P14P (ER and EV) for output. I settled on the Russian 6N3 and Bendix 2C51 for input. I did not have the GE 5670’s that Skylab had but will try them soon. There was a big improvement with the upgraded tubes over the stock units. The EH EL84’s were particularly smooth and lacking any trace of harshness.
The Yarland with the EH EL84’s had a classic tube smoothness in the midrange and treble where the Bada PH-12 tended to have more of a solid state sound. The Bada had better bass slam and the bass dug deeper. The Bada had better dynamic range and did not sound congested during complex music passages. I am finding that many amps seem to not be as problematic with midrange and treble. It is the lack of problems with bass, congestion during complex music passages( in general, most solid state amps have faster rise time and slewing ability) and dynamics that seem to elevate the top amps from the rest of the pack.
The Doge 6210 retains more of the traditional pure tube lushness, when compared to the Bada, in the midrange and treble. The Doge uses different 12AX7 input tube types than the Yarland’s 6N3 but they both use the same respected EL 84 output tubes. I wish we could listen to exactly the same tubes on both the Yarland and Doge. Then we would be able to compare the sound differences of the amps themselves rather than the sound of different tubes. With the upgraded tubes on both amps, bass from the Doge sounded more full with the hard to drive AKG 701. The tight sound of the Yarland’s bass complimented the Senn 650’s. Many complain the bass is a bit overpowering on the Senn’s and interferes with the midrange. The Yarland provided a balanced sound with the Senn 650’s and this was my favorite headphone match.
The Yarland also did well with most of the IEM’s I tried. I get hum through the Bada (I know the reason it hums: Because it doesn’t know the words…sorry) with most of the IEM’s I tried. I would not recommend the Bada if I was interested in driving IEM’s.
The Yarland comes with a 300-ohm outlet that worked well with the Senn 650’s. There is a 32-ohm outlet that worked best with IEM’s such as the Shure E500 and the new Future Sonics M5. Many complain of the Senn 650’s as a bit bass heavy and the Future Sonics M5’s have a similar sonic signature. I have not found many tube home amps that sound good with IEM’s but the Yarland really made the Future Sonics sing and they sounded as good as I have heard them.
The Yarland had a bit better detail than the ASL MG Head MKIII. The ASL in OTL mode and the Senn 650’s results in one of my favorite combinations for providing great soundstage. But the definition is just too much better on the Yarland, and ultimately more accurate to the source. The macro definition along with the ability to drive IEM’s pushed the Yarland’s rank above the ASL. It is a close call near the top of the rankings and I can see how some would prefer the ASL for it’s lush soundstage if you used Senn 650’s.
Treble
Smooth and tube dependent. The amp allows the sonic character of the tube to flow. You would be surprised how many amps restrict this. I think simply getting out of the way and allowing the sound of the tube to flow is one of the most important characteristics of any tube amp.
Midrange
Same as above. As you roll tubes what you will hear is more the difference between the tubes and not the amplifier. This is what many tube lovers strive for and is a sonic trait of the best amps.
Bass
Not the deepest and lacking the impact of the best but has good pitch control and avoids the one-note bass of many tube amps.
Image
Open and smooth presentation without a hiked up treble presence.
Dynamics
Good with the Senn 650, Future Sonics M5, Shure E500 and other IEM’s tried. Not as good with the AKG 701’s.
Yarland P-100 vs. Bada PH-12: Winner-Bada PH-12
Doge 6210
(most of the other amps have pictures posted with their reviews, but I can post pictures for other amps if you would like)
I find myself largely in agreement with drartherwells review here:
http://www.head-fi.org/forums/showth...highlight=doge
I did not want to like this amp. I was very happy with the Bada PH-12 and thought it would be almost impossible to beat. It took a long while to find an amp I liked as much as the Bada; one I could just relax and stop listening to equipment and just enjoy the music. I was “sold” on the idea of the Bada’s hybrid design. My thought was that the hybrid design would ameliorate two often-quoted problems I consistently heard with tube amps:
1-Speed (and subsequent micro detail) not as good as solid state
2-Bass on tube amps not as tight or deep as solid state
I tried to keep an open mind regarding all tube amps and I am glad I did. Regarding my two above listed reservations:
1-The Doge is detailed
2-Bass is very deep. It also is taught and natural on a level with solid state amps without the bass bloat I have heard with other all tube amps.
If you think the AKG 701’s are bass-lite you need to hear them with this amp. I do hear a difference between the Odeum and General settings with General having a wider soundstage. The build quality has not been discussed much and I find it to be well built, but the aluminum panel finish and lettering on my unit are not up to the Bada’s level if I was to nit pick. Parts are typical higher level Chinese but you will not find any Black Gates or Solen parts in here. The front panel is very thick brushed aluminum with a heavy overhead bar that allows you to move the amp like a tool box….a nice touch I have not seen elsewhere. The amp runs cool, which is a big plus toward preserving the life of internal parts in my book. The knobs are aluminum not silver colored over plastic as on some others. If they cut costs on the knobs it makes me worry about where else they may have cut costs. The power output is .5 watt which is a bit lower than what I would like to see, but this amp seems to no problem driving the AKG’s and the Senn’s with headroom to spare.
The Doge just gets out of the way and allows the sound of the tubes to flow through. It is hard to choose favorites at this high level. The quantitative differences at this level frequently amount to the differences in sound of cables, which is small. At this level, you may be listening to the differences in the tube types (i.e. 6922’s, 6SN7’s etc.) and subsequent brands selected by the designer rather than the sound of the amp itself. There are fans for different tube types just as there are for different opamps with solid state gear. Many long-term tube rollers seem to prefer the 6SN7’s used in the Bada and they may be right. But I worry about the heat that may wear down the internal parts of the Bada. And you do have to be careful with the mosfets on the Bada. The Doge does seem to have a bit more homogenous and even presentation, perhaps because it is all tube. This one is very close. The Bada has slightly better macro definition and transient attack compared to the sublime Doge presentation. To quote a famous review “There is more “”There”” there” with the Bada.
Treble
Sparkles without calling too much attention to itself. Lots of air around instruments and voice if it is in the recording.
Midrange
Good micro detail and not overly rich or tubey. Just right.
Bass
The best I have heard from an all tube design
Image
Not pinpoint precise as some solid state amps can be.
Dynamics
Among the best for all tube design. Does not sound congested during complex music passages.
Doge 6210 vs. Bada PH-12: Winner-The Bada by a hair
Xtra X1
I know, it is a portable not a home amp. But I thought it might be instructive to see how this competes as many people ask how a portable compares to a home amp. I refer people to Skylabs great portable amp comparison for more details:
http://www.head-fi.org/forums/showth...t=portable+amp
This amp may have been the biggest surprise in this entire comparison at how good it sounded and how well it compared to the home amps. As good as the Xtra X1 sounded; it was not rated as high as some of the other portables in Skylabs portable comparison. I have heard a Hornet (with an unimpressive MP3 source) and a few other portables but could not compare them for the purpose of this test. The Bada winning this particular shootout was not a surprise, but the margin of victory was not as big as you would think. On some efficient IEM’s like the UE Super Fi 5 Pro’s the Xtra was quieter than the Bada at low listening levels.
I am cringing in pain as I write this in anticipation of the flames from folks who think these tiny portables cannot sound this good driving full-sized headphone. If you think this new generation of portable amps sound is improved please comment, as there will be many home amp lovers who disagree.
Treble
Clean with surprisingly good shimmer on cymbals. Much improved over the older opamp based portables that could sound like water drops on a hot radiator.
Midrange
Once again, clear without the old opamp coldness.
Bass
Not the deepest or the most impact but surprisingly good.
Image
Lacking the air that you find in home amps. Imaging is a weak point.
Dynamics
Amazing power and punch even when compared to a home amp.
Xtra X1 vs. Bada PH-12: Winner-The Bada
Presonus Central Station
Ferbose’s updated review:
http://www.head-fi.org/forums/showth...entral+Station
and the original with help from Music Man:
http://www.head-fi.org/forums/showth...entral+Station
I admit to being biased towards tube sound. My wife is a classically trained musician and I like rock, so we go to a diverse mix of live concerts from the symphony to jazz and hard rock. Tube amps just sound more like music to me for all genres particularly classical and jazz. With rock it becomes harder to choose. However, I know many musicians with home studios that swear that solid state gives them a better window into the music that is being recorded.
I was biased against the Central Station when I saw it had an opamp based headphone amp, and the opamp was not that highly regarded. But a musician
http://www.fishertheband.com/
and producer
http://www.ronw.com/studio.html
who I trust had one in his home studio so I gave it a try. I was wrong, this is a great sounding headamp. It goes to show you that parts alone do not determine the final sound quality. With all the other features such as switching flexibility, great DAC and state of the art preamp, this unit is a steal at the price. But this is only a ranking for the headphone amp.
The Central Station does almost nothing wrong. I could very happily live with it’s clean sound mated alongside rich sounding headphones like the Senn’s. The Senn’s do not really need the richness most tubes impart, but still sound surprisingly good with many tube amps. But times are good for us headphone lovers and there is a seductive quality to music played through any of the top tube amps that is tough to beat once you are used to it.
Treble
Clear but lacking the air around the intruments that comes with tubes. The decay is not as well done.
Midrange
As above
Bass
Taught and deep. I was surprised to get deep bass out of my Shure E4C.
Image
Precise and a strong point of high end solid state
Dynamics
Good punch and plenty of power.
Presonus Central Station vs. Bada PH-12: Winner-The Bada PH-12
SinglePower PPX3
I borrowed this amp because I wanted to see how it sounded before I bought one as it was a bit more expensive. This is the non-Slam version with Solen upgrade and the 6SN7 tubes that I like. SinglePower and Ray Samuels have a very loyal following for good reason.
-Both have a reputation well deserved for reference standard, almost super human support and service. This is remarkable considering how finicky and difficult to please we headphone people are.
-Both use expensive high quality audiophile approved parts from start to finish. You will not see cost cutting by committee with these folks.
Many of the Chinese companies are hiding under the desk feigning communication problems when it comes to offer post sales service and support. They don’t get it and do not believe that lack of service will diminish point of sale decisions. When weighed against the added cost of providing Class A support, they would rather have a few less sales to fussy audiophiles.
But this is a tough field and we are ranking products by sound quality so I will try to be objective. I am putting on my nomex asbestos flame suit for this one because of all the loyal followers of SinglePower on this forum.
The chassis is not overbuilt and the quality of parts used is very high. I will cut to the chase and say the PPX3 6SN7 was a top sounding amp. It did not have the last bit of micro detail and dynamics on this example. I was hoping for more bang for the buck, but the Chinese offer intense competition at this price point.
Treble
Smooth and rich. You can easily hear the differences between lean tubes and rich tubes with this amp…a good sign.
Midrange
Same as above.
Bass
Good texture but lacking some impact.
Image
Images float well and sound open
Dynamics
Just a bit off
SinglePower PPX3 6SN7 vs. Bada PH-12: Winner-The Bada PH-12
Bada PH-12
Here is one of the original reviews for the Bada:
http://www.head-fi.org/forums/showth...highlight=Bada
And an alternate view:
http://www.head-fi.org/forums/showth...highlight=Bada
Much has been said about this amp, but it offers great definition for the money. I caution every Bada owner to wait 24 hours before you remove any tubes. It you remove tubes before the current dissipates your will blow the delicate Toshiba mosfets. The fix is easy, but just wait and be safe. This design begs for some type of bleeder resistors and I am looking into doing this without compromising the sound. You get Solen and Rubycon audiophile grade parts in this amp and 1 watt of power. It may be the extra power of the Bada over all tube amps that provide the extra bit of macro dynamics that I prefer.
The fit and finish on the Bada PH-12 is quite good. The amp is heavy with a nice brushed aluminum top panel and black clear front panel that lets the LED’s shine through. Many seasoned users feel the (vintage NOS) 6SN7 tubes used with the Bada are the best for driving headphones over other tube types.
Here is a quick test: On the SACD version (or the redbook version which is still very good) of Miles Davis-Kind of Blue you can hear the extra bite the Bada has on horns and in the critical midrange. Most tube amps smooth this texture and you do not hear the bite that is there when listening to live instruments. On Diane Krall-Love Scenes track #7 “I Don’t Stand a Ghost of a Chance with You” (an audiophile reference recording) see if you can hear changes in the mix (including tape hiss) as her voice stops and starts. The Bada does not smooth out the sound of female vocalists and gets the acoustic bass notes being plucked just right.
Caution: I have not got the best sound from the Bada with sensitive IEM’s like the UE Super Fi 5 Pro’s and I did not care for the Grado’s with this amp.
Treble
Very detailed but lacking some of the natural smoothness of all tube designs.
Midrange
Good definition
Bass
Solid to the lowest octave with good impact
Image
Pinpoint precise without the diffuse image on some tube amps.
Dynamics
Powerful and a reference standard
Bada PH-12 vs. ASL MG Head MKIII: Winner-The Bada PH-12
G&W 2.6F
A nicely designed and built amp. This is another hybrid design that I am biased to like. But unlike the hot running Feel and the hotter flame throwing heat from the Bada, the G&W has a nice large external heat sink that runs cool to the touch without need for a fan. The G&W also runs mosfets with tubes, in this case a pair of 6922 types.
This is a solid amp with good drive that does very little wrong. It sounds quiet with IEM’s and drives low and high impedance headphones well. We are reaching a high level and the detail and air of the G&W fall short of the ASL.
Treble
Lacks the shimmer and sheen on cymbals of the best tube amps.
Midrange
Vocals and acoustic instruments lack air.
Bass
Deep and solid.
Image
Sounds more solid state than tube.
Dynamics
Plenty of power.
G&W 2.6F vs. ASL MG Head MK III:Winner-ASL MG Head MKIII
Little Dot III+
Sword Yang’s (Little Dot’s designer) attempt to upgrade the entry LD II+. This is an ambitious design:
-Solid and vented chassis solves the heat problem of the LD II+
-Heavy duty isolated power supply
-Switch selectable triode or pentode mode
-Auto detecting headphone impedance circuit
-Ability to drive speakers through rear binding posts
-Upgraded parts including Wima, Vishay, Nichicon ALP Blue Velvet volume pot
With all of this my hopes were high as I really liked the LD II and II+. One thing I noticed was the LD III+ solved the congestion problem mentioned with the LD II+. This amp has rhythm and pace even when pushed.
However, one aspect working against the LD III+ was a slight lack of transparency compared to the LD II+. Perhaps this is due to the more simple and direct circuit path the LD II+. I suspect that the additional auto-impedance detection circuit may be a cause for the reduction of transparency. It does work well and I have not seen this feature on any other design. I did not have a schematic for the III+, but did want to get one in order to experiment with disabling/removing the board that senses headphone impedance and suspect that may clean up the sound a bit.
Treble
Smooth but lacking air
Midrange
Same as above
Bass
Good impact and deep in Triode and Pentode mode
Image
Wide and deep
Dynamics
Good overhead without the congestion noted in entry LD amps
Little Dot III+ vs. ASL MG Head MK III:Winner-ASL MG Head MKIII
ASL MG Head MKIII
This design has evolved over the years (along with the price which is now $500) and has improved. You have a switch to toggle from OTL and transformer coupled mode. This was a mod suggested quite a while ago on an older version in these forums and I wonder if the importer took note. In OTL mode the sound with the Senns is one of my favorites: lush and very musical. This amp lacks a bit of the micro detail of the very best, but makes up for it by presenting such an open window on the music you don’t miss it. It also runs cool and is quiet without the hum problems of earlier units. With this amp we are approaching the top tier.
Treble
Rich with good decay.
Midrange
Very realistic without being hyper detailed.
Bass
Not the tightest, but good texture.
Image
Wide and deep, a strongpoint.
Dynamics
Surprisingly good with the Senns even in low power OTL mode.
ASL MG Head MK III vs. Feel HP-100A: Winner ASL MG Head MKIII
Ming Da 66
The Ming Da is well built with heavy power supply. A robust power supply at the top of my list and helps determine how much the manufacturer has invested in producing good sound. The parts quality and wiring also was of good quality. I have had Ming Da integrated tube amps that sound good and similar to my Cayin/Prima Luna amp. Everything seemed in place.
This amp lacked the air, detail and definition of other tube amps. One of the methods I use to determine this is listening to how the amp responds to tube rolling with top respected tubes. With top amps, you should be able to clearly hear the difference between tube changes as you do with opamps. The Ming Da exhibited a muffled sound that you had to listen through to discern tube differences. I am biased toward tubes but this amp does not squeeze out the most detailed sound in a tube. It was also noisy and did not do well driving sensitive IEM’s.
Treble
Smooth and tubey, a bit rolled off.
Midrange
Richly defined .
Bass
Not tight and bloated. An example of tube bass looseness.
Image
Wide but diffuse lacking specificity.
Dynamics
Hard to determine due to the bass overhang.
Ming Da 66 vs. Feel 100: Winner-Feel HP-100A
Xiang Sheng 708B
Not the best build quality on this amp, but the price is low. The chassis is thin stamped steel, PCBs are thin (we like military specification boards) and the ALPS labeled volume pot looks like a “copy” (AKA knockoff). The tube in the front opening is for display only and does nothing but act as a nightlight as far as I can tell. We are not off to a good start and this is not what I would call a robust design.
Stock, I preferred the LD II+ in terms of build quality and sound. The Xiang was a bit harsh with the stock tubes and it sounded more congested than the LD II+ did when pushed. The Xiang sounded better with high impedance headphones and had trouble with inefficient headphones.
However, as noted in the extensive mod thread for the Xiang
http://www.head-fi.org/forums/showth...ht=xiang+sheng
this amp is easy to work on and can be modded. The tubes are relatively easy to find and you can make improvements in the sound just by upgrading the tubes alone. I had problems with the volume pot not tracking equally on both channels. But this amp does show improvements with tube rolling that can clearly be heard, perhaps due in part to it’s simple basic design. I like modifying FM tuners and this amp reminds me of a stock Kenwood KT 7500. It is an easy to work on, is a 5 gang tuner that does not sound great stock, but the aggregate improvement from several key mods (opamp, power supply, filters etc.) improve this to a world class tuner.
Treble
Harsh with stock tubes.
Midrange
Congested during complex music passages.
Bass
Not the deepest.
Image
A bit bloated and not well defined.
Dynamics
Lacking punch.
Xiang Sheng 708B vs. Feel 100: Winner-Feel HP-100A
Little Dot II+
Price creep becoming an issue as the price went up to $145. However, you get smoother Mullard tubes on the front end that are easier to find and roll. However, you also get preamp outputs, which worked well.
http://www.head-fi.org/forums/showth...&highlight=dot
Controversy about tube arching hurt the reputation of this amp after I wrote the above review. I think much of this was due to a bad batch of the 4P1S power tubes. The good news is that you can order replacements from Little Dot. But other sources for this tube or finding different branded versions of the 4P1S have proven difficult at best. Some have argued that the problem was not merely a bad batch of tubes and point to subsequent modifications in the new version of the amp to support that point. My analysis is that there was a bad batch of 4P1S tubes. Subsequent modifications were made to help prevent arching in the event of future defective tubes (such as bleeder resistors) but I believe the cause of the arching can be traced to bad tubes. Replacement tubes were sent out at no charge and the customer service from David (the Ebay seller) and Sword Yang (the designer) was first class despite the bargain basement price of the amp.
The following is taken from the above listed review.
Treble
The LD II+ has a different presentation and is not as bright as the LD II. The LD II+ has a smoother high end with longer decay.
Midrange
Richer than the LDII.
Bass
A bit more full and sounds closer to typical tube amplifier bass.
Image
Slightly improved depth of soundstage, width is about equal. It sounds less solid state and more tube like.
Dynamics
More rounded presentation is less congested with better delineation during complex dynamic passages.
Little Dot II+ vs. the Feel: Winner-Feel HP-100A
Little Dot II
When these first came out the price was around $95 plus shipping. A replacement set of 4 new tubes was and additional $15.
My original review is here:
http://www.head-fi.org/forums/showth...&highlight=dot
Please note my comment regarding congestion during complex music passages with this amp. Despite the heat issue, this amp allows an entry to tube sound for users who might not ever consider it.
The following is taken from the above listed review.
Treble
Shimmering cymbals with very musical decay
Midrange
Lush and life like, but lacking the last bit of detail of the very best tube amps.
Bass
Full with great impact. Not as tightly detailed and lacking the pitch and speed of the best.
Image
Great soundstage but does not have the pinpoint precision of the best solid state designs.
Dynamics
A strength of this design. If you are used to similarly priced opamp units in this price range you will be pleasantly surprised by the improvement.
This is comparison is close but the congestion issue hurt the LD II. If not for the congestion, I might give preference to the LD II.
Little Dot II vs. the Feel: Winner-Feel HP-100A
Pioneer A35 Integrated amp
I would like to find a well-built integrated amp that also has a good headphone amp with a functional preamp and switching capabilities. I had a Fisher 400 tube receiver that was pretty good at also driving high impedance headphones. Why is it hard to find a mainstream speaker amp with an audiophile level headphone amp that utilizes the same chassis and heavy power supply? A few years ago Creek had an integrated amp that also had a nice headphone amp built in but it was expensive. I have heard the Portal Panache. It sounded clean, but I have not compared it directly to a headphone amp.
The Pioneer is not bad, but I would still not give up my dedicated headphone amp.
Treble
Quiet, but I can hear the grain with low impedance headphones.
Midrange
Not the last word in definition.
Bass
Full but lacking detail.
Image
I lost interest for critical listening.
Dynamics
Strong with high impedance headphones.
Pioneer A35R vs. the Feel: Winner-Feel HP-100A
Marantz 2230
The amp section on the receiver is similar to the amp of the Marantz 1060. Mkmelt (and others) has posted that this amp has a decent headphone port for high impedance headphones. You should budget money to replace the caps and have the unit serviced because these units are 30 plus years old. The tuner is not good on these, but the phono preamp is good. I had mine upgraded with Panasonic FM caps
Treble
Can sound overly smooth with little transient response.
Midrange
Smooth and tubey sounding.
Bass
The bass was full but lacking definition.
Image
Hard to tell due to overall lack of definition.
Dynamics
With a full size power supply, there was dynamic range and a lack of congestion.
Marantz 2230 vs. the Feel: Winner-Feel HP-100A
Rockhopper M3
I liked doing business with Rockhopper, but when I last checked he has stopped building amps. I have heard versions of this amp that sounded different with different parts, more than other amps I have compared with different configurations. This amp had 8610 opamps that I preferred with the Senns and Elpac “wall wart”. The amp can be improved with better power supplies.
Treble
Not a lot of air or sparkle and somewhat recessed.
Midrange
Rich and clean but prominent in the mix.
Bass
Solid and strong.
Image
Lack of air hinders the presentation and depth.
Dynamics
Good with Elpac, better with improved power supply and audiophile caps.
M3 vs. the Feel: Winner-Feel HP-100A
Feel/OK 2000 HP-100A Hybrid
This caught my attention as what looked like an incredible bargain. The build quality, case and features were similar to the $1000 plus Headroom amps at the time, yet this cost around $200. The Feel used 6922 tubes with a mosfet output. This combination of tube low level preamplification combined with solid state output was first brought to my attention by the Absolute Sound editor Harry Pearson in 1976. His reference system was the Audio Research SP 3A tube preamp and solid state GAS Ampzilla amplifier and I had this set up for a while and the soundstage sounded incredible. I went to the Soundcraftsman preamp because it had a 10 band equalizer and patching features I needed for field recording along with clean solid state sound, but the SP3A sounded more like music.
The Feel ran very hot despite heavy external heatsinks. It has an input select switch for 2 inputs. It sounded closer to solid state than tube.
Treble
Smooth but lacking some air at the top.
Midrange
Clean but not as smooth as an all tube amp.
Bass
No tube bloat here
Image
A bit diffuse but better than the PPA
Dynamics
Good punch
Feel 100 vs. the PPA: Winner-Feel HP-100A
PPA
This was the version 1 without the diamond buffers and with an Elpac. This was considered one of the better DIY amps when there was not much to choose from in the $300 range only a few years ago. Still a clean sounding amp.
Treble
Sharp and clear
Midrange
Clear
Bass
Tight and lean and a good match with the Senns. Not as full sounding as the M3.
Image
Precise but not wide or with depth
Dynamics
Improved over CMOY and Pimeta
PPA vs. Pimeta:Winner-PPA
Enhanced CMOY
An upgrade of the original design with a socketed 2134 opamp and audiophile parts.
Sounds similar to the original CMOY but the signature can be voiced by changing the opamp
Enhanced CMOY vs. Pimeta Winner-Pimeta
Pimeta
When this design first came out they were touted as an improvement over the CMOY.
Treble
Fast attack, little decay
Midrange
Clean but lacking tone body
Bass
Punchy, but with little deep bass
Image
2D
Dynamics
Limited
Pimeta vs. CMOY:Winner-Pimeta
CMOY
One of the first in a wave of DIY designs
Simple design that took advantage of a wave of clean sounding audio opamps capable of driving headphones.
Clean sounding but cold and sterile presentation
Treble
Clear, a strength of this simple and clean design
Midrange
Same as above
Bass
Taught but not deep
Image
A bit flat and newer designs made big improvements
Dynamics
Limited
First amp: CMOY
BACKGROUND
I started my headphone search back in the 70’s, and I am surprised at how little headphone and tube amp technology has changed since that time. My system consisted of many Absolute Sound recommended components:
Headphones
Koss Pro 4AA, Sennheiser HD 414, AKG 240, Stax SRD-7 with Stax SRX MKII.
Speakers
Dahlquist DQ-10
Electronics
GAS Ampzilla amplifier
Soundcraftsman PE 2217 preamplifier
Source
Thorens 125, 126
Technics SP-10
SME tonearm non-detachable head
Grace 707
Marantz 120
Revox A-700 half track
Tandberg 10X-D
At the time, when I “upgraded” to the Stax system they cost as much as used car (for a college student on a budget). I was very disappointed in the lack of bass impact and cold sounding midrange. None of the headphones had the depth and image of a pair of properly set speakers like the Dahlquists. If this was (among) the best headphone sound available I would prefer to listen to speakers.
Over the years I tried various flavor of the month headphones but they did not compare to the sound of speakers. Only recently, I started critical listening with headphone amps. JMT designs (Anyone remember him? Great guy.) were popular and I tried some of his amps. They were around $150-$300 with a good power supply and the best parts in models like the Pimeta. With the Senn 580 or Grados they showed promise.
SYSTEM
Headphones
AKG 701
Grado 225
Grado 80
Senn 650
Senn 580
Koss Portapro
Koss KSC 75
Koss KSC 35
Shure E4C
UE Super Fi 5 Pro
Altec IM 716
JVC FX-33 Marshmellows
Panasonic HJE-50
Senn MX 500
Speakers
JM Labs Cobalt 820
Acoustic Research AR-9
AER Pisces V.2
Several 8 and 10 subwoofers
Sound Dynamics RTS-3
Electronics
Cayin TA-30/Prima Luna tube integrated amp
Aragon 2004 MKII solid state power amp
Aragon 24 preamp
Acurus DIA 100 integrated amp
Belkin Power filter
Monster Power filter
Source
Sony SACD 333ES CD player
Rotel 991 CD player for HDCD
Technics A10 DVD-A player
Presonus Central Station DAC
Philips DVP-642 transport
McIntosh MR 67 tuner
Acuphase T100 tuner
Vinyl reluctantly given away
METHODOLOGY
Regarding test methodology: I have tried to test the same source connected to the Aragon 24 preamp, a passive switchbox, and now the Central Station. I then connected 2 headphone outputs to a simple “Y” junction box I cobbled together with 2 of these Xin suggested cables:
http://www.radioshack.com/product/in...entPage=search
and SPDT toggle switches on each input so I can switch one off and then the other on to a single headphone output. I found this extra cable blunted the transients a bit but it did enable instant A-B comparisons. I did most of my listening with the most simple connection of source to headphone amp and then to the headphones. I used the Rotel 991 via the analog output (for HDCD that I like) and with the Presonus DAC (for redbook only), Sony SCD 333ES for SACD (my favorite) and the Technics A-10 for DVD-A. I used the Silver Audio Silver Bullet 4.0 with silver WBT connectors as an interconnect. I also used a Monster 1000A Power Filter and the Belkin Pure AV PF30 filter with different power cables. The stock cables were used with the AKG 701,Senn 650 and 580. Level matching is absolutely critical and hard to get right.
I used the tubes and opamps that came with the amps for the purpose of this review. Most of the stock tubes supplied with these amps are not the best and many refer to them as “throw aways” or worse, and I agree. However, in an effort to be consistent and avoid tube preference arguescussions I had to base these reviews on the original configurations.
I am not affiliated with any of the above companies. I am not an employee of any of the above companies or vendors. I do not own stock in any of the above companies nor do any of my relatives that I know of.
I am open to any ideas and comments regarding how to improve these comparisons and this format.
EPILOGUE
I worked at a software test lab for years. When the explosion of video games started, we were contracted by Disney, Sony Studios and others to test game software. I found the project managers for the game software to be brilliant, innovative and among the best in the business. I suspect the designers for the new wave of portables are also at the leading edge of design and this is where the energy and talent is focused for headphone amps. This is not surprising, as I have read that vendors in China report they sell 10 portable headphone amps for each home amp sold.
My preconceived notion that opamp based headphone amps could not sound as good as tubes has been challenged by amps such as the Presonus Central Station. I still prefer tube amps. However the gap is closing.
DOCUMENT UPDATES
3/12/07-030507homeampreview original document
3/12/07-030507homeampreview1 grammar change
3/13/07-030507homeampreview2 added CMOY info, added Feel pics, add opamp detail, added epilogue
5/24/07 added Yarland P-100
