an amp without "electronic" sound


Could you give some recommendations for a power amplifier without the usual electronic/mechanical sound? It is easy to say: "tubes", but in my opinion tubes are not always the way to go. I myself prefer solid state (because of several reasons).

Chris
dazzdax
Most of the recommendations you'll get are going to be tubes. But class D amps did this for me. The Bel Canto eVo series in particular. I find the sound to be natural and non-fatiguing.
There are many makers out there now so I suggest you give one a try, if it's not to your liking you could sell it with minor loss. I did this with the newer Bel Canto S-300. Bought it used and sold it a month later for exactly what I paid. The compact size was a plus but it did not sound as good as the older eVo version IMO.
The Pass amps have a reputation for lacking an electronic/mechanical sound.
Asking an electrical/electronic box/unit not to sound like itself is like asking a Harley to sound like a Honda.Up late last night?I know what you mean,but do you know what your asking?Good luck,Bob
Most musical & emotional amplifier without any electronical /mechanical sound is absolutely without doubt the eternal immortal classical FM acoustics FM-800 or FM-801 period !!
no roll off treble, very detailed, and unmechanical sound
If Lavardin makes a power amp they might fit the bill. Pass amps are very neutral from what I have heard.

Avoiding the 'electronic' sound is the name of the game IMO and what drives us audiophiles to begin with...
I'd go for a the tried and proven Class A design with modest levels of NFB. However, if you want warmth then tubes is the only way to go (but you know that).
in my experience it's difficult to find a sand amp that will give you what you want without spending very big dollars.
Larry
Sand amp...another gem,kind of like a hydraulic sandwich if your an Angel....have a large day men,its looking good already and its still early,cheers,Bob
If you dont have grain free amp to begin with ,,,room and treatments dont make any difference,why fix something already broken?
For me it was also the Bel Canto Evo 200.2's (running monoblock to power my ML SL3's, but I think similar can definitely be said of the BAT VK amps.
Chris, you have been busy lately.
No Electronics could sound without a tinge of electronics. Only difference would be to find one with least autonomous electronics. I have not come across any yet. My Jadis Orchestra Ref does surprisingly well but it can't play loud due to power limitation. I am hoping that the Zanden 9600 mono I will audition soon will achieve that.
How about Fm acoustics and Lamms? You have claimed FM acoustics to be the one of the best. Did you try thoes?
Good implementation of SET amplification can sound astoundingly natural and present, as can OTL (the latter having less 'limitations' as SET with perhaps a 'cooler' presentation for lack of a better descriptor - perhaps it is they are more neutral). The SS amps that I've owned that come the closest to having the qualities you describe have been Bel Canto Ref 1000's. Ultimately I prefer tubes, but the Bel Cantos were very engaging to me.
when i was ready to go from solid state to tubes 7 years ago i found that i preferred OTL tubed amps as they seemed to have the linearity of solid state while also having the 'breath of life' of tubes. also; they were not rolled off top and bottom. however; OTL's typically need a very easy load to be optimized. for 5 years i used OTL's.

then i heard the solid state darTZeel amplifier. the dart had the naturalness of the OTL; but also better clarity and was more micro-dynamic.....and no tubes.

if you want a non-mechanical sounding amp but not with tube color.....you need to listen to the darTZeel. it sounds like music to me.
I'll third the Nuforce SEV2's. No transformer, no tube, just amplification on a stellar level. Still however, to add a little bit more soul, a very good tube pre would be magical..
I just listened to the Ayre integrated with some B&W 805s (and compared it to the Classe integrated, among others), and I have to say I love the Ayre. I am buying one shortly.
Dazzdax, if you want the amp to not impart an electronic quality, I can tell you that the list of candidates is not very long. On top of that, its likely that you will have to accommodate the amplifier in some way, as the relationship between any amplifier and speaker is paramount.

First, in order to avoid an obvious electronic quality, the amplifier has to be designed with intention to obey the rules of human hearing, rather than the more arbitrary rules that are commonly used to get the best bench measurements.

For example, we all know that humans have bandwidth of about 20Hz to 20Khz. To accomplish that without phase response issues, the amplifier has to be good from about 2Hz to 100KHz or so. Otherwise it will impose soundstage issues and tonal issues near the frequency extremes.

For audiophiles, one of the more important 'electronic' issues is that of brightness and other high frequency artifacts. The only way to avoid this is to intentionally design the amplifier to not make the odd-ordered harmonics that the human ear uses as loudness cues (and so is sensitive to 100ths of a percent!).

To do this you cannot employ loop negative feedback as it is known to enhance those very harmonics that the ear uses to gauge loudness.

So now we are limited to amps without NFB. How do we achieve linearity? Distortion **has** to be kept down, even the even-orders that our ears do not object to, because another human hearing rule, masking (wherein a louder sound will mask a quieter sound), means that the non-objectionable distortions will nonetheless mask low level detail.

To keep distortion down you have to use every trick in the book: Class A operation, the most linear devices (more on that later), simplistic circuitry (by 'simplistic' I do not mean crude or primitive BTW, which includes but is not limited to a minimum number of gain stages) and otherwise eliminate any other known distortion-causing design characteristics.

The most linear devices known are still triodes. If you are not going to use them, the design field is really limited; you are looking for a zero feedback class A transistor amplifier: Pass Labs, Ayre and Ridley Audio are good places to start.

Transistors themselves are known distortion-inducing devices, so if you allow yourself tubes, the field is considerably larger.

SETs are capable of very low distortion at low powers as they usually don't have hysteresis-induced distortion in their output transformers. Bandwidth and power is problematic and you need higher efficiency speakers to appreciate them. But recent advances in the SET art have made for some impressive gains in transformer design area; this is the edge of the envelope with SETs.

Push-pull amplifiers have power and bandwidth, but suffer loss of low level detail due to hysteresis losses in the output transformer. Two of the more impressive tube designs, especially in light of the fact that they are *not* triode are the CAT amplifier and the Modjesky RM-9. Triode push-pull amplifiers will generally run 300bs or other Directly Heated Triodes (DHT).

OTLs, having no output transformer, avoid the bandwidth and low level distortion issues on that account. This gives them the low level detail of SET combined with the power and bandwidth of push pull, although the bandwidth is usually considerably wider. Choice of speaker is something that has to be paid proper attention as it is with any amplifier.

In general tubes should not be paired with speakers of lower impedance (although this turns out to be true for transistor amplifiers as well, if the best sound possible is your goal). Its a bit of a red herring to fault tubes for not having the 'current' to drive low impedance speakers; the reality is that you want the best tool for the job; butter knives don't make good screwdrivers :)

I apologize for the verbose post, but the subject merits detail as it is at the very heart of what high end audio is (or should be) all about.

Dear Chris,

I highly recommend the Spectron Musician III SE. This amp is absolutely grain-free and has a fast and organic sound. It is extremely transparent as well.

I started with one amp and added a second one in mono-block balanced configuration a few months later. With these amps, there is a ease to the sound that is hard to find in non-tube designs.

Best Regards,

iSanchez
All the Jeff Rowland Design Group's amps with Power Factor Correction. These noise level is exceedingly low and the response is neutral yet robust and super dynamic.

Dave
Ralph, I've just read your post and it is fantastic. I love the way you explain things and make the complex stuff simpler so even a electronic nitwit could understand. Thank you.

Chris
Chris, be careful of generalities. When you get into the top echelons of each design technologies, the characteristic benefits and difficulties narrow.

Dave
Is it possible to go tubes but also having clean sound? I just got a 845 tube amp, sounds warm, but it's very muddy...
Hi Chris,

Take a look here -

http://www.redwineaudio.com/Signature_30.2.html

This is the one to beat as long as you do not need hundreds of watts of power for inefficient speakers.

-Nate

05-14-08: Toufu said:
"Is it possible to go tubes but also having clean sound? I just got a 845 tube amp, sounds warm, but it's very muddy... "

It's probably just a mismatch between the amp and your speakers. The best tube amps really don't sound warm. A great amp, tube or SS, should be transparent, open, stress free and uncolored.

Dave
As Nate mentioned, you should definitley put the Red Wine Audio 30.2 or 70.2 on the top of your audition list!

Good luck,

Jeff
Toufu, the short answer is 'yes', but I would not automatically assume that all triode and all class A amps will be 'clean' and neutral. Re-read my post again- one thing about SETs and push-pull transformer coupled amplifiers is that the larger you build them, the harder it is to get the output transformer to have full bandwidth.

Please correct me if I am wrong, but having an 845 I am assuming that your amplifier is an SET. 845s make a bit more power, in fact that is very large for an SET, and it is also very difficult to get wide bandwidth with such an amplifier. Fifteen to twenty watts may not sound like a lot, but for an SET it is. The best sounding SETs will be 7 watts or less.

Fifteen years ago the 300b power tube was the reigning star- with them you can make an amp that is more or less 7 watts. That was supplanted 7-10 years ago by the 2A3, which is about 3-5 watts. Nowadays the 45 is the big news, and that's only good for a watt or two.

That's what I meant about needing high efficiency speakers. If you have speakers that are less than 103 db or so, its very difficult to experience what these amps have to offer.
While I prefer tubes, I would say the Pass XA.5 series (Class A, little NFB)have a lot of the what I enjoy about tubes. I regret having sold it (XA30.5). I think you will find much of the same qualities in the Ayre gear as well.
Dave, even in the highest echelon you can hear clear differences between amps. With some of the amplifiers that have ultra high resolution you do not only hear the beginning and decay of tones but it's as if there is "air" or texture surrounding the notes even prior to the beginning of the sound. Take a guitar player. With a high resolution amplifier you can hear all the notes and decay of tones but with the ultra high resolution amp you hear tiny movements of the air molecules (probably caused by the movement of the guitar player's arm or change in his body position). This is what I actually mean by ultra high resolution, not the hyperdetailed scratchy treble that is the hype today. If you hear this phenomenon once you will never forget the sound. Many high end manufacturers are not able to achieve this sound quality even when they have the financial resources to make it happen. I know you'll probably condemn me because of serious bluntness and narrow-mindedness but I'm only trying to describe some phenomena I've encountered during listening sessions.

Chris
No, not at all Chris. I think we're actually on the same wave-length, so to speak and no pun intended. I myself want TOTAL resolution, with no added "hyperdetail" or unrealistic treble, but also no euphonic colorations. With my recent move to Rowland I think I've gotten very near. I need more weeks of listening to validate my early impressions.

The question comes to my mind, since you know so much and seem to have a well thought out position, based on apparent actual listening experience, then what do you think meets your criteria as the OP here??? (I'm not poking you my friend, this is a real question).

Dave
1 - Spectron Musician III SE Mk2,
2 - Jeff Rowland 312,
3 - Plinius Reference.
Dcstep, to achieve what Dazzdax is talking about you need an amplifier that has a remarkable combination of characteristics. It should be fast, which is a problem for a lot of tube amps, but it should be relaxed, which is a problem for a lot of transistor amplifiers. Detail and transparency of the kind needed for this resolution comes from very low level distortion at low power. Any distortion-inducing design elements (devices woth poor linearity, class of operation issues, etc.), in the circuit will impede this quality.

The amplifier is more important than the speaker in this respect, so you must get a speaker that works with the amp that has the right qualities, rather than the other way around. **Figuring out** which is the right amp to buy to begin with is another can of worms entirely :)
Atmasphere, I've been talking about detail and transparency all along. So what amplifier would you recommend? Rather than talking about concepts, why not get specific?

Dave
Hi Dave, of course, I think our amplifiers suit that bill easily :)

The short list:
I admire the Ridley Audio transistor amp; its expensive but it is one of the best I've heard (tube or solid state). I'm also a fan of the Pass First Watt amps. Of the SETs that I have heard, the only ones that have worked for me (so far) are the DeHavilind and the Fi 2A3 'X' model (the Art Audio stuff works quite well too). With larger tube amplifiers the CAT seems to me one of the best. In amps of a bit less power the Modjesky RM-9 and the Berning amps figure highly.

I've owned the CAT JL2 for a few years, and now own the Music Reference RM9 Special Edition (Modjeski)and these are among the finest amps I have heard, but for speed, detail and transparency and presence (the others are obviously no slouches in these areas) I think the Atma-sphere M60s are very tough to beat with the right speakers (I own Merlins which are OTL friendly - highish, smooth impedance)- I wish I had not waited so long to try the OTL waters.