When I did my review of the amazing Matrix M-Stage amp, I mentioned that I was not really a tube fan. More specifically, I had enjoyed tube amps for short periods of time but generally tire of them after a short while. The only exception to this has been the wonderful DarkVoice 337SE which has lasted for several years in my collection. Given my history and the fact that I already own one nice tube amp, I figured I was done with trying them out. I was wrong.
When I did a mini-review of the Linear Designs headphone stand I noticed that the seller also had some amps for sale under the name Fournier. He had a solid state model and a tube model, and both came in standard amp form as well as amp/DAC form. The seller contacted me after my earlier review and offered to send me his Fournier HTA-1 hybrid tube amp to evaluate. He offered to pay shipping both ways too. How could I refuse? The item sells for $179 plus reasonable shipping from inside the USA.
I’ll ruin the suspense right now and tell you that after a few weeks of listening, I have purchased the amp. After having it in the house for a while I simply don’t think I can be without it. I certainly did not intend to buy it but so it goes with really nice gear. I don’t know how long it will hold my attention but for now I am extremely pleased with it.
The Fournier HTA-1 is a hybrid design with a tube preamp section and solid state output stage. The best description I can offer was actually given to me directly from Dave, the maker of this product. He is a lot better at explaining how his baby works, so I will quote him (with his permission of course):
“The HTA-1 is a hybrid tube amplifier. The input stage is a tube cascode gain stage utilizing the dual triode 12AU7 tube. The 12AU7 was chosen for its lower gain and favorable triode characteristics. The voltage gain in the HTA-1 is all in the tubes. Thus the signal and sound qualities are dominated by the tube gain stage. Tubes are operated at relatively low bias currents, which make them generally incompatible as low impedance output drivers without some impedance transformation; commonly in the form of a transformer output stage. Alternatively, a zero voltage gain MOSFET stage can be used, which acts as an impedance buffer to take the tube amplified signal and drive the headphone load without using the non-linear characteristics of the semiconductor device for voltage gain. This combination yields a zero-feedback amplifier stage which has the favorable gain characteristics of the tube and the low impedance drive capacity of the MOSFET. What does this all mean? The amplifier has the “warm” sound of tube amplification with plenty of drive capacity.
Recommended headphones: 30 to 300 ohms (Grado, AKG, Sennheiser) My favorites are the Sennheiser HD-650’s.
As far as competitive amps, I am not the one to ask. I have built all of my gear. I compare it to solid state designs with pristine electrical specs. Anyone into high-end audio knows there is more to it than that... a speaker or headphone is not a resistor, far from it… it is a complicated electromechanical network, yet a resistor is the demarcation point most amplifiers are designed and marketed to.”
I found his description both informative and honest, especially that last paragraph. I had asked him how he feels the HTA-1 compares to other available amps. He could have easily told me how much better it is relative to inferior designs on the market, as there is never a shortage of bad gear being sold and used. But he took the high road and basically left the ball in my court to decide how his amp stacks up to the rest. I appreciate that.
The amp ships with 2 JJ brand 12AU7 (ECC82) tubes. Dave says the tubes are easily removable for tube rolling purposes, and that the sockets are gold plated ceramic and should stand up to the abuse. The amp is self biasing so rolling should be pretty easy. I happen to think the stock JJ tubes sound excellent on their own, and since I don’t have any others handy I have not switched them out. Dave says he keeps some Electro Harmonix around in case the buyer wants those, although I didn’t ask if there was an added fee. He says that he has tried vintage RCA tubes and felt the stock JJ performed just as well.
The HTA-1 has a fully discrete output stage; there are no opamps in the unit at all. It features a 20dB gain on the tube side, and a 0dB gain from the solid state output section. Output impedance is 35 Ohms. It has one set of RCA stereo inputs as well as a 1/8th inch input, which takes priority over the 2 since there is no switch. The front is a simple design with a power switch, a large volume knob, and a fairly bright blue LED. The blue light also shines though the tubes when powered up; I’m unsure if this is by design or simply bleed over from the front panel LED, but I actually think it is quite nice looking. Most small signal triode tubes don’t really have much of the “tube glow” that people might be expecting, so the extra blue light really livens things up a bit. But that’s a matter of personal preference. I tried my best to capture it in the pictures so judge for your self.
The HTA-1 is fairly well built. The case appears to be aluminum (or aluminium depending on where you live) and only comes in blue, which Dave calls “Process Blue”. It’s fairly unique and really stands out amongst my more spartan black gear. It has nice little non slip “feet” on the bottom which I never used to appreciate until I got a few items that don’t have them….. and constantly slide around, scratch things, or get scratched. I also appreciate the rubber grommets that surround the tubes. They aren’t as fancy as tube rings or cages but they are likely more functional.
Although everything is fairly well done, it isn’t too hard to find telltale signs that this is a hand built unit. I see some glue residue around the rubber grommets. The rear inputs don’t line up perfectly with the holes cut for them. An etching on the back panel of an arrow (indicating signal flow in to the unit) seems slightly crooked. I tried to capture all this in my pictures; as you can hopefully see, none of it affects function. What it does is give the unit a bit of character, reminding the user that it was carefully hand assembled.
If you have skipped forward to the pictures, you will have noticed that I didn’t post my usual internal shots. There are several reasons for this. First; when I took the pictures I was not yet the owner of this unit and thus did not want to damage it in any way. Second; I can’t find my #10 TORX which is required to remove the front and rear panels. Third, Dave mentioned that he used loctite on some of the mounting screws for reliability reasons, so the thing will likely not come all the way apart anyway. These three things combined with my general laziness were simply too much to overcome; the HTA-1 would have to be appreciated from the outside only. Although I haven’t seen the inside myself, the specs indicate quality parts are used. Names like Vishay Roederstein, Wima, Alps, Dale, etc show that Linear Designs did not cut corners when building this amp. I might work up the motivation to try for an inside view….. we will see.
One interesting aspect of the amp is the power supply. It comes with a Hewlett Packard power supply originally used for a laptop PC. The auction lists this as a used part, although the one I got looked brand new. I discussed power supply with Dave and this was his reply:
“The power supply is a very very important piece of any amplifier. The HTA-1 is a class A amplifier which means the power supply load (the HTA-1) is constant regardless of the program material. The power supply is also one of the largest expense items in a piece of high end audio equipment. The HTA-1 draws about 0.4A from the remote power supply, yet the remote power supply is rated at >2A, which is a factor of 5 times greater. There are two reasons for this... performance and reliability. From a performance point of view, an over-rated power supply will be able to supply not only the average power required by the amplifier (the RMS rating), but can replenish/sustain the power lost/used during the peak transients in the music program. I can go on and on about this topic, but to summarize, I highly agree the power supply is a critical component of any high quality audio component. The HP brick supplies an economical high power density source for the HTA-1. I debated designing my own power supply for the HTA-1, but figured the extended cost to the customer would be prohibitive entering the market. Once the product line is established, a custom high end power supply is a logical extension to the product line. I will always try to offer an economical alternative with very close technical performance.”
That makes perfect sense to me. I’m sure there are some that would scoff at the HP solution. My thinking is that it is very likely to be superior to any of the wall wart type solutions that are usually supplied at this price point.
The only other thing worth mentioning is that the rear RCA connectors are not as deep as usual. Check my pictures to see what I mean; it's like they are a bit recessed into the case and there is not a ton of room around them for the cable to slide into the opening. I didn't find this to be a problem with any cables I had on hand including Ethereal, Impact Acoustics SonicWave, Luminous Audio, Monster, or Choseal. But I could see it being a problem with some big heavy cables like Kimber Hero HB that demand a large RCA jack to grab on to. those would probably cause this little amp to tip over, but still..... Thought I'd mention it.
The HTA-1 arrived well packed with plenty of bubble wrap. It does not have a commercial looking box or anything, just the amp itself, a small instruction manual, the power supply, and a basic 3.5mm to RCA cable. The manual is only a few pages, but is pretty informative, covering much of the info I’ve discussed here.
For sources I used my Pioneer Elite DV-37 CD player and a QA-350 solid state player from QLS HiFi. The Pioneer is somewhat of a classic that recently underwent surgery and now has a full suite of upgrades from Burson Audio including a precision low jitter clock, low noise regulator, and quad opamps. The QLS QA-350 is something I recently picked up and am very impressed with, review coming soon. For variety I also used a Sigtone Shek D1 NOS DAC, a Gamma2 DAC, and the Audinst HUD-mx1 DAC for a bit of PC listening. Comparisons were done with a few amps including the Matrix M-Stage, the built in amp of the Audinst, a DarkVoice 337SE, and a bunch of other Ebay sourced tube amps that don’t belong to me. Headphones used include the AKG K702, Sennheiser HD650, Monster Turbine Pro Copper Edition, LiveWires Trips, and some Grados which also don’t belong to me. Cables are my usual no nonsense items from Blue Jeans, Impact Acoustics, Ethereal, and others.
I’m somewhat tired of listing each and every track or album that I listened to for reviews. I’ll summarize by saying that I listened to a bit of every type of music, on either redbook CD or 16/44.1 WAV file. I did try a few 24/96 tracks from the PC but that was the minority. Read some of my older reviews if you are dying to know specifically what some of my favorite music is.
I did my usual burn in for at least 100 hours just to make sure things work properly. I noticed that the aluminum chassis seems very good at helping dissipate heat. After several hours of loud playing, the HTA-1 gets warm to the touch pretty much all over the case. Not too hot to touch, but definitely warm. I like this better than some products that get roasting hot in one small area and but stay cool everywhere else: to me that’s a waste of a good cooling space.
Rather than list every single headphone, amp, DAC, etc and how they interacted with the HTA-1, I’m going to summarize a bit more than I have in the past. This is in keeping with my attempts to keep from being too long winded.
My fist impression of the HTA-1 was that it sounded startlingly close to my DarkVoice 337SE but with a hint more of a “tubey” sound. I like how the DarkVoice has all the authority and low end grunt of a good solid state amp. While the DarkVoice accomplishes that through brute force, the HTA-1 gets the job done by means of its hybrid design. The mids have that super realistic, wide open midrange that good tube designs can give. At the same time, there is none of the loose, weak, or sluggish bass that some tube designs can have. The more time I spent with it, the more I enjoyed it.
The words that come to mind to describe the sound all seem to be related to sight, and I don’t know why that is. Words like sheen, shimmer, and glow all capture a bit of the sound experienced with the HTA-1. As I mentioned, it is more tube-like than the 337SE but not extremely so like the original Millett (non Max) or the Opera Consonance Cyber 20 that I used to own. It ends up walking a very fine line between tube and SS sound, with a slight leaning to the tube side but still fairly balanced.
At under $200, I would not expect this amp to be the best in the world. And it isn’t. It can’t quite match the transparency or amazing detail of the Matrix M-Stage, nor the vast soundstage of the 337SE. But I just don’t seem to care. This thing is so musical, so fun to listen to that I honestly stop caring about any flaws it may have and just enjoy it. It helps that those flaws are fairly minimal: It’s not too sharp up top, nor is it too rolled off. It’s not too boosted on the bottom end nor is it thin and boring. And those mids? Superb. Lush but not so much that it is too thick or syrupy. It especially excels at attack and decay, both the fast and slow versions of each. I think this is another reason why it is so involving and musical. The key to that aspect seems to be the power supply, and having enough juice to sustain even the toughest musical content. Again I’ll quote the designer and his thoughts on the matter:
“With regard to the power supply current... the AVERAGE current/power drawn by the amplifier is constant for any given program material. The peak current delivered to the load can draw excess current from the power supply. Two extreme cases could be the build-up of a pure tone from a flute (a slow attack), and the opposite would be the crack of a snare drum or a hard note on a piano (fast attack). In this case, the power can be the same, but the instantaneous current required from the percussion instrument (drum or piano) would sound a whole lot better with a low impedance (beefy) power supply. The amplifier with a cheap power supply would test equally well as an expensive power supply using a frequency sweep. There are no power dynamics in a swept audio measurement... it is a constant power amplitude changing only frequency. A test to find a cheap power supply would be a repetitive percussion event (or an extended note on a bass or cello). If the power supply is made “beefy” with predominantly capacitors, repetitive percussion events can discharge the caps and the power supply does not have sufficient constant current capacity to replenish the charge as it is depleted. A single transient percussion event would sound good, but a drum roll or extended bass note would decay the reserve power stored in the power supply capacitors faster than it could replenish it. Since the peak to average power in music varies this quality, or lack of, would be highly music style dependent. So even having “headroom” can be differentiated as instantaneous headroom or sustained headroom. This is where the power supply matters. The HTA-1 has a 62 watt power supply, and only delivers typically ~20-30 milliwatts RMS to a headphone.”
Again we can clearly see we are dealing with someone who knows his stuff when it comes to design and implementation of his product. And also we see why that HP PSU is actually a good thing.
I found that the HTA-1 was equally adept for almost all types of music. From Jazz at the Pawnshop (Arne Domnerus) to Bossa’N Beatles (Rita Lee), Don’t Sweat the Technique (Eric B and Rakim) to Before and After Science (Brian Eno), everything came out rich, warm and highly enjoyable. If I had to pick a musical weak spot, it would be music where no “real” instruments are involved…. Not because it sounds bad necessarily but simply because the HTA-1 excels at capturing the lifelike sound of instruments. When dealing with machine-made sounds (Kraftwerk for example) I found that I just didn’t connect with the music as much as with real strings, woodwinds, etc. Still, its performance in that area is nothing worse than “average” and at this price I shouldn’t complain.
What headphones does the HTA-1 like? The answer is easy, but depends on your definition of the word “headphones”. If we take it to mean “full size supra aural or circum aural” designs then the answer is quite simple: all of them. You may be thinking “What about in ear monitors?” Well that’s a bit more complicated. The problem is hiss. I find that most IEMs I have are just too sensitive and end up producing a medium to high amount of hiss when used with this amp. The worst offenders are the very sensitive Westone ES3X and the LiveWires Trips, which are borderline unlistenable. Others such as the Monster Turbine Pro Copper are a lot more manageable but it is still not an inky black background. If you mostly use IEMs this likely isn’t the amp for you. On the upside there is no tube hum to be heard, and there is even a slight startup delay to help avoid loud pops when powering the unit on. I've accidentally touched the tubes while listening and there is no noise to be heard at all. This is not your average finicky tube amp.
When I say the HTA-1 gets along well with pretty much every headphone I have, I really mean it. Sennheiser HD650 sounds just about as good as I have ever heard them. The added warmth in the upper mids really helps them seem more balanced than usual, and the bass hits deep and hard. AKG K702 sounds excellent as well, with a touch more fun injected into its usual analytical sound. The bass is tight and controlled and perhaps just ever so slightly boosted but it is still by no means a headphone for bass heads. The best part is that for the most part, they keep their usual sense of balance, to the point of being somewhat boring to certain people. I happen to like them a lot but I understand the complaints. When using the Monster Turbine Pro Copper Edition with the white supertips, the HTA-1 helps their already dynamic sound become almost like my Audio Technica L3000; huge yet controlled bass, excellent clarity and separation in the midrange, and smooth highs that fall just short of the best available. I wasn’t sure if the already fun Coppers needed any more character but I’m really liking what I hear. On the flip side, I didn’t like them as much with the regular tips, which I normally use for classical. The HTA-1 gave them a bit too much lower midrange energy and they became less balanced. I also found the hiss somewhat distracting with classical; I use the tri-flange or supertips for other types of music and the hiss is much less of a problem in those cases.
At my house I have a Grado PS1000, RS1, and SR325. But I’m not really that familiar with many of the other Grado models. So I was excited when I took this amp to a friend’s house and he had an HF2, woodied SR80, GS1000, and an Alessandro MS-Pro to try. The HTA-1 seemed to be an excellent match with all 4 of them, and I preferred it to the amps he had available. I found it hard to choose between the different Grados as they all sounded so good, but in the end I thought the HF2 slightly edged out the MS-Pro for first place, with the GS1000 coming in at third and the Woody SR225 still sounding sweet even in last place. The HTA-1 seems to work best with bowls rather than flats. I’ve always thought flats were better when taming a bright sounding amp, or when you wanted to add a bit more body to the mids. The HTA-1 already has rich, textured mids and smooth controlled highs so flats are just not needed. I did also like the GS1000; that headphone sounds (to me) very different from the other Grados but still interesting. The HTA-1 provided it with an even bigger soundstage than it had with the other amps we had on hand (Eddie Current ECSS, Gilmore Lite, and Grado RA-1), and really helped the bass dig deep. I can confidently say that the HTA-1 is superior to all three of those amps in almost every aspect. I can also confidently say that the PS1000 is overpriced since some of these Grados sound so close for so little money.
One of my favorite headphones at any price, the LiveWires Trips are unfortunately not so good with this amp. The hiss is just too strong to overcome in most circumstances, which is too bad as there is some amazing sound hiding in there. I’ve discussed this with the designer of the amp, and he has some ideas for future products; one idea involves a gain selector, the other idea splits the line into a lower gain version and a higher gain version. I like the idea of gain selection if it can be done for a reasonable price increase.
Comparisons between amps are tricky. The differences are usually not night and day, and often times you end up improving one area at the expense of another. With that in mind, I put the HTA-1 up against a few amps I own to see how it stacked up.
This $179 USB DAC has a very powerful built in amp. It is very neutral and balanced, and frankly amazing for its size and price. The HTA-1 doesn’t try to match the complete neutrality of the mx1, but in my opinion beats it with superior realism and control, especially in the attack and decay areas as I mentioned earlier. This could very well be a byproduct of my using the stock power supply with the mx-1. In any case, the HTA-1 gives just enough tube bloom to liven most music up in a positive way, and I would choose it pretty much every time. The combination of the two of them (mx1 as DAC feeding HTA-1 as amp) playing high res music from the PC is quite good, and for under $400 I’d say they have some real synergy together.
This thing is close to $1,000 so it really isn’t much of a fair fight. Nevertheless, the HTA-1 seems to play follow the leader pretty well here. It comes up just a tad short with regards to the holographic soundstage, and has a bit higher of a noise floor. The DarkVoice has even better transient response, which you would hardly think possible when listening to the Fournier unit. This might be due to the extremely robust dual mono power supply that the DarkVoice uses. The 337SE also makes a killer pre-amp (I used to run mine with a Parasound Halo JC1 and it was an amazing combo) and the HTA-1 can’t do that at all. Other than those areas they are just about even, which really highlights the price increase you pay as you go ever higher up the audiophile ladder to try and secure that last few bits of fidelity. Still, I’m not sorry that I purchased the DarkVoice.
Although the M-Stage sells for $270, let’s not kid ourselves; it is really a Lehmann Audio Black Cube Linear and thus belongs to a similar class as the DarkVoice mentioned above. Still, I’ve spent enough time raving about it that a comparison to this new amp is a must. The M-Stage is one of the best solid state amps I have ever heard. It is neutral, detailed, powerful, and basically transparent when used with decent gear. I still find it to be a steal even though the price has increased by $20 since I reviewed it. The price could go up another $100 and it would still be a steal. The HTA-1 is able to match the M-Stage in many areas such as power, control, dynamics, and soundstage. Again it falls short by having a higher noise floor and again it has less versatility. Comparing these two amps is a bit tricky though as they really have a different sound signature. The Matrix is very transparent while the Fournier subtly adds a bit of extra flavor to the music. If the goal is perfect audio reproduction then the Matrix wins every time. But for pure listening enjoyment, the Fournier has been getting more play time in my setup for the past month. I especially prefer it when listening to less than pristine recordings; it won’t make terrible sounding albums like St. Anger (Metallica), Vapor Trails (Rush), or Californication (Red Hot Chili Peppers) sound great. It’s not a magic device. But if something is just mediocre, the Fournier will give it a touch of euphonic coloration and make it sound quite nice. I especially found this useful when listening to albums from local bands that didn’t have huge budgets for recording, but gave it a nice effort anyway. Ultimately if I had to recommend an all purpose amp for someone who only intended to own one amp, I would have to go with the M-Stage. But for someone who wants to try a tube amp, and won’t be using IEMs, the HTA-1 is now my first recommendation. If one could afford it I would say buy both and get the best of both worlds.
Other Ebay tube amps
I took the HTA-1 to visit various friends in hopes of comparing it to some other budget tube amps. I was surprisingly successful. I was able to do some (unfortunately too brief) comparisons with a Phenix G3, a Bravo tube amp, a Sense G1, a Bada PH1, and a HiFiMan EF5. Some of these are cheaper than the HTA-1 and some cost a bit more, but all are tube amps and all would be considered competitors. I don’t mean to put any of these down, as some sounded quite nice in their own way, and with more listening time I might grow to love any one of them. But from my initial impressions, the HTA-1 was clearly superior to all except for the EF5. It just had a better handle on the balance between coloration and neutrality, and had better transient response as well. The EF5 was a bit closer of a competitor. They are both hybrid designs although the EF5 has an opamp in the output stage and the HTA-1 is fully discrete. I initially thought the EF5 was slightly better due to the "blacker" background (I hate that term), but then they evened out due to the HTA-1 seeming to have a certain richness to the bass that the EF5 couldn't quite match... I couldn’t decide. The owner of the EF5 thought the HTA-1 was clearly superior, but I just couldn’t quite agree. Either way it is pretty impressive considering the price difference. I wish I had an EF2 on hand for comparison.
The Fournier HTA-1 is an excellent little amp. It is hard to believe such power can come from such a tiny device. It seems to have just the right amount of euphonic coloration without going too far into tube town, and its transient response is top notch.
Soundstage is very good but not excellent, and general resolution is fairly high. It is not the most versatile amp in the world as it is not great with sensitive IEMs, and it is not as silent as some other amps out there. Other than that issue I can find nothing to complain about. Build quality is very good and the price is more than fair in my opinion, especially for a hand made product. It works well with all types of music but excels with giving real instruments a great natural sound. I heartily recommend it!
The only other thing I should mention is that the designer (again, super nice guy!) sells a version with a built in DAC that might be worth looking at. It is called the Fournier DAC-1 and is the same as the HTA-1 but with an included Burr Brown PCM2704 or PCM2706 USB DAC built in (they are virtually interchangeable). The DAC-1 sells for $50 more than the HTA-1. I already have the several higher end USB DACs around so I didn’t opt for that model. If you are interested in the HTA-1 and don’t already have a decent USB DAC, it is certainly something to consider. It is not an ultra high end unit and is limited to 16/44.1 resolution, but I doubt you could get anything better for anywhere near the $50. Just something to think about. Note that I haven’t heard it myself but I’m going on the high respect I have for the designer.
After discussing the hiss that I'm hearing, the designer made me an attenuator for use with IEMs. It is about 8 inches long, and performs roughly the same function as the old Etymotic P to S adapter used to do.
When in use, this amp is now very quiet. Still not silent, but certainly on the level of most of the $1000 or less amps that I have ever owned.
Listening with a good pair of IEMs, this amp is very pleasing. It handles them much in the same way as it does full size headphones. It has such great control and extension in the bass region, which is almost surprising given that tube amps aren't exactly known for that. I also particularly like the way it can help strip away that "digital harshness" that often appears on CDs and makes them sound so digital. Again I'm not talking about working miracles, but it can help a pretty good recording sound really good.
I don't notice any negative impact from using the attenuator. Some people had issues where they felt the old P to S adapter changed the sound somehow (I can't remember and never owned one myself) but thus far I haven't noticed any of that here. Just smooth warm music with a dark background.
Linear Designs advised me that they will be selling the adapter for $14.99, which is less than attenuators that I've seen selling on eBay recently, and way less than the real P to S used to cost. The plan is to eventually change the product to an HTA-2 which will feature dual headphone jacks: a 1/8th inch jack for IEMs and a 1/4 inch for full sized cans (basically building the attenuator in to the unit). The price will go up to $195, so it is the same as buying the current product and the adapter. Either way the result is an excellent and versatile amp that punches way above it's price point. I can honestly say that this little amp gives you 85% or more of the performance of the DarkVoice 337SE for 20% of the price. This is an ideal companion to a solid state amp like the Matrix M-Stage, but would satisfy my needs as a solo amp if I ever needed to sell most of my gear for some reason. It might not be as visually commanding as some of the HiFiMan units like the HE5 but it performs right up there in the same league, and for less money.
Edited by project86 - 6/15/10 at 3:02am