[Borat]

Quote:

Originally Posted by Skylab /img/forum/go_quote.gif Excellent! I will await your report. And I will be prepared to be proven wrong again - Earl already says his PPX3 is completely silent, and I believe him. So I guess I should have said "most tube amps are not completely silent" Let's now allow this diversion to end.

Sorry to add to it.

I've owned the PPX3 and PPX3 SLAM and I had the same experience as Skylab. Very slight buzz on both at full volume with no music playing. I actually sold the PPX3 to Skylab so his response was expected. I totally ripped you off, bro!

I'm not educated about what causes the buzz (Tube? Power? The pot?), but every tube amp I've owned (Singlepower, Eddie Current) had this in different degrees. In fact, I don't think I've ever owned any amp (ss or tube) that was completely black at full volume with no music playing. I hear a slight buzz on tube amps and a faint hiss on solid state. For ss, I've owned several portables, the HR-2, and now the M^3.

Not that this ever affects my enjoyment though since I never go past 9-10 o'clock on the volume dial during normal operation.

 

[jamato8]

Who cares if there is hiss at max volume? I have designed and made amps and this has nothing to do with real sound. Years ago I would run up the volume control and say "wow" there is hiss. After I really got into it and started working on amps I realized that it has nothing to do with sound. A hiss at listening volumes is often the source but if the amp then some changes need to be made but all the worry about hiss at louder than normal volumes doesn't mean anything.

I can't believe that a manufacture that totally stands behind his products, communicates by phone and email, upgrades his products, goes to meets, and goes out of his way to be helpful is getting grief in this thread. Well I can believe it, it seems to be the nature of some people, including myself at times. We are all fallible but man can we forget that.

I sum it to say that there are manufactures that produce good sounding equipment but lack on customer service and the other way around but Ray hits high on all marks and even offers refunds. Damn how much more can a person do?

 

[Skylab]

Quote:

Originally Posted by Gradofan2 /img/forum/go_quote.gif I wouldn't think a little tube hiss at full volume would make any real, audible difference at normal listening volumes... so... does it really make any difference?

Quote:

Originally Posted by Borat /img/forum/go_quote.gif Not that this ever affects my enjoyment though since I never go past 9-10 o'clock on the volume dial during normal operation.

Quote:

Originally Posted by jamato8 /img/forum/go_quote.gif Who cares if there is hiss at max volume? I have designed and made amps and this has nothing to do with real sound. Years ago I would run up the volume control and say "wow" there is hiss. After I really got into it and started working on amps I realized that it has nothing to do with sound. A hiss at listening volumes is often the source but if the amp then some changes need to be made but all the worry about hiss at louder than normal volumes doesn't mean anything.

EXACTLY on all points, a little hiss at high volumes is MEANINGLESS. Totally meaningless. And whether 100% of tube amps have it, or 98%, or heck even 50%, it matters NOT AT ALL. That was, in fact, the point I was originally trying to make! No one should be too upset that a tube amps makes a little hiss at high volumes.

If it buzzes audibly or hisses audibly at normal listening levels, that isn't something I consider acceptable, although until one has tried multiple tube sets, one will never know if it's the amp or the specific tubes causing the issue.

 

[vcoheda]

here are some relevant comments re raptor + low impedance headphones, just in case people are curious about the amp's ability to drive/handle these type of headphones.


Quote:

Originally Posted by Ray Samuels It is normal to have more volume (sound) /per volume knob turn when using high impedance headphones like the Sennheise 600/650 with the tube OTL design amp. While you need more turn of the volume knob to accomplish the same level of sound when using the low impedance headphones like Grado. Now it is true also that the apposite happens when using the SS headphone amp. The high impedance require more turn on the volume knob to reach the levels of the low impedance headphones which do not require a lot of volume turn.

Quote:

Originally Posted by john_jcb I have had the opportunity to listen to the Raptor with many different headphones and I believe your statement may be taken in the wrong way. All tube amps behave in the same manner. All tube amps require a higher volume setting to drive low impedance headphones. High impedance headphones like the Senn 650's require a much lower volume setting than low impedance to achieve the same volume. As stated earlier Solid State amps exhibit the opposite; low impedance, low volume setting. high impedance high volume setting. The key when evaluating a tube amp with low impedance cans is not the volume setting but rather the quality of sound at that setting. The Raptor sounded very good to me with low impedance Grados even though it took a higher volume setting. There are tube amps out there that really have a problem driving lower impedance cans. When a tube amp is having problems driving a headphone there is no mistaking the degradation in sound. The Raptor had no problem driving the Grados to higher sound levels than I find comfortable.

Quote:

Originally Posted by recstar24 The Raptor is an OTL design, without the aid of output transformers OTL tube amps naturally are abit more efficient with the high impedance than low impedance, its a better impedance match. And the 650 sings beautifully with the Raptor, in fact after I reviewed the Raptor and had to turn it in, it was hard for me to go back to the 650 without the raptor, the experience was so exhalting that the 650 did not sound the same after that experience. For an OTL design, the Raptor does a great job driving the low impedances compared to some other OTL designs, which includes the eddie current HD-300, Skorpion HV-1, and Antique Sound Labs MG OTL. A lot of these OTL tube amps suffer from a light, mushy type bass and lack extension at the extremes due to the impedance mismatch of the high output impedance of the tubes going into the low impedance of the cans; however,the Raptor in my experience drives the Grados with authority, great extension, very percussive and chest hitting bass, silky highs that extend up and above the whole upper harmonic series, with the great mids that one would expect from one of Ray's products.

Quote:

Originally Posted by Ray Samuels The Raptor does not & will not chug with HP-2 or any headphone you drop on it to a very comfortable listening levels. But, all tube amps which are made out of pre-amplification tubes in the OTL configiration, will drive the high impedance phones to higher levels at less turn of the knob, though many can not make it with the low impedance hard to drive Grados. The Raptor drives ALL low impedance phones with ease, to ear bleeding levels of listening, due to the drive capability of the 5687 output tubes. The only thing the low impedance require is more turn of the knob to get to those levels of sound.

Quote:

Originally Posted by Ferbose I recall the Raptor drove Grado RS1 with ease. So I don't think Raptor has any difficulty driving low-impedance cans. To my ears I like Grado with SS amplification for rock, although most of the times I am a tube guy. But that's just me and I know I hear Grado very differently from most poeple. For example, I don't think Grado is bright but actually think it has recessed extreme treble. I do recall that I liked jazz more on RS-1 than HD650 driven by SR-71. YMMV.

Quote:

Originally Posted by donlin I hope that nobody has the impression that the Raptor does not work well with Grado's. I have been using the Raptor with Grado RS-1's for 3 months and I think it is by far the best amp for Grados. It also works very well with HP-2's. I have been listening to Grado's for almost 15 years with many good amps and the Raptor is a perfect match. I think it is a good thing to have a little more range on the volume knob. I usually have the volume between the 9:30 and 10:30 position.

Quote:

Originally Posted by tyrion I've been using my HF-1's, which just arrived, with my Raptor for the last couple of hours and it drives them easily. It does take a bit more of a turn on the volume knob to achieve the same volume level of my 650's. I am listening comfortably at almost 10:00. With my 650's I would be at just about 9:00. There is plenty of detail, nice punchy bass.

 

[sacd lover]

Quote:

Originally Posted by Gradofan2 /img/forum/go_quote.gif I'd like to know... since I'm in process of "kicking tires" to buy a new tube amp. I wouldn't think a little tube hiss at full volume would make any real, audible difference at normal listening volumes... so... does it really make any difference? And... itsn't it a function of the specfic tubes used and their gain, as well as the sensitivity of the phones used, as well as the overall gain of the amp? Isn't the background noise on most recordings a more relevant consideration at normal volume levels? I'm very impressed that the SP's of SACDLover are so quiet - is it a function of the above factors, or are his amps just better, or what? And... most importantly... does it really make any difference, unless its really audible at normal listening levels?

One thing to consider is the sensitivity of the headphone itself and the relative gain of the tubes in the amp. You definitely will hear less noise from the low sensitivity AKG 701 vs the high sensitivity Alessandro MS2. The SP's can use a number of tubes and I favor the 6gu7 for gain which has a lower mu/ gain of 17.5 vs something like a 2c51 which has a mu/ gain of 35. Impedance may be an issue too but sensitivity seems to have a greater effect .... atleast in my system.

I commented because I know my PPX3 amps are quiet all the way up. But, really all that matters is if the amp is dead quiet at your normal listening levels. I do appreciate that the amp remains quiet well above normal listening levels, however.

My Extreme gets close with most headphones. My Sound Quest SQ-84 does as well, especially with high impedeance Senns. The Space Tech Lab I have is noisy with any low impedance headphone but goes almost up to the max volume without noise using 6gu7's with tube socket adapters and Senn 580/600's. The Doge 6210's are noisy unless I find just the right set of tubes, very picky .... and they do better with high impedance headphones. Interestingly I have more noise issues with the transformer coupled amps I own than I do the OTL's.

 

[philodox]

Quote:

Originally Posted by Skylab /img/forum/go_quote.gif EXACTLY on all points, a little hiss at high volumes is MEANINGLESS. Totally meaningless. And whether 100% of tube amps have it, or 98%, or heck even 50%, it matters NOT AT ALL. That was, in fact, the point I was originally trying to make! No one should be too upset that a tube amps makes a little hiss at high volumes. If it buzzes audibly or hisses audibly at normal listening levels, that isn't something I consider acceptable, although until one has tried multiple tube sets, one will never know if it's the amp or the specific tubes causing the issue.

My position on this as well. Incidentally, though we ultimately both agree anyways, my amp makes no discernible sound at max volume with no music playing. There is no difference between minimum, maximum or any of the gradients in between. The only thing I could hear to tell that the knob was being turned was the mechanical clicking sound my stepper makes, though that is not transmitted through the headphones themselves.

EDIT: After reading Earls post I tried again with my Grados and it's the same story.

 

[Skylab]

That is interesting. So I stand corrected - it's possible to have a 100% silent tube amp, although, I think, not common. I just tried my SP Extreme again, and starting at about 80% full rotation, there is a very small amount of hiss that is barely audibly (this is with 600 ohm DT990's). Perhaps if I used a regular 6SN7GT instead of the ECC32 this wouldn't be the case, BUT I don't care - I prefer the sound of the ECC32, and since by the time I reached 80% of the volume I would have blown headphones, ears, and amp, it's just not a problem

 

[Covenant]

Quote:

Originally Posted by tagosaku to OP. Why do you need faith to a particular amp designer/maker? Is there any reason you don't want to move on and find something you like ?

Because I like RSA as a business and aesthetically, and have been trying to find out if another venture into his products would be worthwhile.

Quote:

Originally Posted by Aimless1 Words not withstanding the OP dragged up an old thread from 9/3/05. No longer has the amp and has moved on to his audio nirvana. Get over it already!

I "dragged up" an old thread to give background to this one. I wanted to understand why my original problem occured and if it was an isolated issue.

Quote:

Originally Posted by jamato8 No. The toroid is totally redone as is the board in the Power supply. They aren't the same amp.

FINALLY some of the info I was hoping to get out of this thread! I was under the impression the toroid had already been modified/changed when I purchased the amp (I'd heard of heat problems with the previous model), but If this isnt the case that's some hope that the current production Raptors may have already fixed the problem.

vcoheda, thank you very much for your input. I had no real conception of the difference between OTL and transformer-coupled tube designs or how it affects their drive.

I'll have to re-read your post thoroughly to make sure I understand it, but does this mean that OTL designs are inherently inferior driving low-impedance headphones to transformer-coupled? That may explain why the Raptor was less than ideal with the Sony SA5000.

Now, the last few pages of this thread have been alot of speculation about my intentions on starting this thread and alot of less-than-complimentary remarks about my taste/judgement in calling question on an amp manufacturer. I had thought I'd explained my reasons for starting this thread well enough in the opening post and in follow-ups, but since I apparently havent I'll make this statement simple:

I was very impressed with Ray Samuels' customer service, product presentation and aesthetics. This makes me want to be a customer of his again, however I was wary due to my previous issues with a product of his. I started this thread wanting to know why my original problem occured, to understand it. This understanding would empower me to know whether my misdoubts about RSA were justifiable, or if they were not, would pave the way for investing in his products again.

vcoheda's information about OTL designs and their strengths/limitations is very useful in that respect, as it gives me a lead to follow to find out if perhaps the Raptor had just been ill-suited from a design perspective to drive my reference 'phones at the time. Likewise jamato8's comment about the toroidal upgrade is useful as that gives another potential point that could have caused my original issue.

I have an Edition 9 on the way, which is also a low-impedance headphone. I'm wondering if a transformer-coupled design would be preferable to OTL in driving these. I've been told that with transformer-coupled the transformer has to be a good one - but in what respect, exactly? Plitron has a strong reputation for audiophile-grade toroidals...

sacd lover's comments about the PPX3 noise floor is valuable as well. I'm wondering what in the design of the PPX3 makes it so silent as to have no hiss at max volume, which as per Skylab's comments is a very difficult thing to achieve.

 

[jp11801]

the plitron in the raptor is for the power supplu not audio output.
When we talk about OTL or transformer output it speaks to whether or not the audio is tied to a capacitor or transformer for output. Every amp is going to have a transformer in the power supply this shoudl not be confused with the transformer or cap in the audio output. You can also have transformers or caps in for interstage coupling but almost nobody does interstage transformers anymore but I understand this can sound great but it leads to increased costs as the transformers need to be top quality.

Ray is not alone is using an OTL design most of the popular tube amps on headfi use them some overcome the issue of low impedance drive better than others though. Transformer coupled amps are making a strong comebacl but at the top $$ segment of the tube amps like the TTVJ 307a and the Balancing Act from Eddie Current. My Eddie Current HD2 is tranny output and sounds great but it uses old tango transformers.

 

[number1sixerfan]

It is fine to talk about a subject that may not be easy to talk about, but to the OP it is all about how you communicate it. The title of your thread can easily negatively effect Ray's rep when(from your own story) it is not really deserved.

I think your thread has provided some great conversation and information about amps in general and Ray as well. But the title was just overly dramatic.

I just think that some of these threads would not be edited and such if people would just communicate their points better instead of sounding so dramatic....but dunno...just thinking out loud i guess. lol

 

[upstateguy]

Quote:

Originally Posted by Skylab /img/forum/go_quote.gif That is interesting. So I stand corrected - it's possible to have a 100% silent tube amp, although, I think, not common. I just tried my SP Extreme again, and starting at about 80% full rotation, there is a very small amount of hiss that is barely audibly (this is with 600 ohm DT990's). Perhaps if I used a regular 6SN7GT instead of the ECC32 this wouldn't be the case, BUT I don't care - I prefer the sound of the ECC32, and since by the time I reached 80% of the volume I would have blown headphones, ears, and amp, it's just not a problem

Hi Sky

I've been intrigued by this hiss phenomena but am unable to get my tube amp, a Woo3, to hiss. I've tried it with 650s, 880s, 701s and a feet of ear buds.... dead quiet all the way up. What do you do to get this hiss to happen?

USG

 

[Skylab]

Well either I have very bad luck or very sensitive ears, because my Woo3, when I had it, did have a slight hiss at the top of its volume range. Again, barely audible, and inconsequential, but there nonetheless.

 

[upstateguy]

Quote:

Originally Posted by Skylab /img/forum/go_quote.gif Well either I have very bad luck or very sensitive ears, because my Woo3, when I had it, did have a slight hiss at the top of its volume range. Again, barely audible, and inconsequential, but there nonetheless.

Did you have it connected to a source and if you did was the source on, or did you just turn the Woo3 on and run the volume up? What headphones were you using? Can I get this to happen with the headphones I listed above? Is it more likely to happen with ear buds than headphones? I'm using a Cetron 7236 power tube from '83 and two jan philips 6922s from '86... what tubes were you using when you heard the hiss?

USG

 

[Skylab]

I was using Amperex 6922s and Tung-Sol 6AS7. Source was off

 

[jpelg]

If you have to work that hard to hear something...