Atma-Sphere and VAC are very transparent (neutral). I believe most tube amps manufactured today are relatively neutral. It's damn hard to find a tube amp with the stereotypical rolled-off and bloomy sound some people associate with tube amps.
Art Audio Diavolo. I love mine!
joule electra otl amps in my opinion are excellent
The Coincident Technology Frankenstein II is the finest most neutral tubed amp available at any price. It may be purchased directly from Coincident Technology. The asking price is a bargain. I have had mine for over 1 year and I have never "looked back."
Tube amp, even it is OTL, has much higher output impedance which when interacts with speaker can cause multiple db swing in the speaker's frequency response. If you really want a neutral amp, don't buy tube.
Leben CS600 Intergrated Amp should be considered.
there is no neutral amplifier. a well-trained listener can detect coloration after auditioning an amplifier for some period of time, with a variety of recordings.
my experience with my mac 275 indicates that the amp has e very minimal coloration.
Cayin A88t integrated, or other similar models, cheap enough to keep for a doorstop if you don't like it.
Very, very, very good sounding for the money, and flexible.
Remote volume and triode/pentode switching...
Good solid sound, and makes audio fun again.
After living with many, and hearing many more...
I'm surprised no one mentioned Audio Research. Their claim to fame is 'neutrality'. And though some think them lean or dry, not compared to ss IMO. I have a Mac 275, like Tennis, driven by a ss Levinson 26s pre, and find that combo close to ideal for me. Although I'm sure any top ss pre would work fine; like Klyne, Krell, Ayre, Boulder, Goldmund, etc.
ARC would seem be leaders in the neutrality arena. I think my CAT JL2 would fall into the neutrality side of the ledger.
there has been a trend in recent years in amplifier design, which i would term convergence. tube amps are sounding more like solid state amps and solid state amps are sounding less "transistory".
most tube amps, excluding some set designs, have minor deviations from neutrality. yes, there is an occasional clunker, but it is not difficult to find a tube amp whose flaws are not objectionable, if resolution is your goal.
"...no warmer, cooler, lighter, darker, or sweeter than the music it transmitted." Atma-Sphere amps and preamps are by far the most neutrally transparent electronics I've heard in my system.
Albeit an 87dB sensitivity, specs on the Opera Callas monitors show an 8-Ohm nominal impedance. I'd give the Atma-Sphere M60s a try.
With regard to Audio Research ... historically I've never thought of ARC gear as quite as neutral as Neil suggests. For a long time they were the yang to CJ's yin. Their turn-of-the-century sound leaned toward a somewhat 'aluminized' flavor. *However* (imo) the latest batch of ARC Reference gear (Ref 3, 210, 610) along with their PH7 phono stage demonstrates vastly improved tonality, as near to neutral as I've heard from ARC. If anything, it is now reveals the barest hint of warmth - not entirely a bad thing.
I think of 'tonal neutrality' as relative - as Mrtennis suggests - you can hear differences in coloration between two pieces of gear, just as you can hear a difference in coloration between two concert halls. Its rare for two different amps to sound the same. 'Tonal transparency', if you will, can be truth relative to the source. How close to the sound of Grumiaux's "Rose" Guarneri does the gear render? Live music is a tune-up for the ears.
I thought my Conrad-Johnson Premier 140 was quite neutral, although as others have said, it is nearly impossible to confuse it with a solid-state amp. The 140 was replaced by LP70S and LP140M amps, so I am not sure how they sound.
The CJ 140 is one of, if not the, most neutral CJ amp I've heard, though by direct comparison it still hints at their house sound, the CJ golden/caramel tonality. My sense is that CJ began moving more toward neutral starting w/ the likes of their 16LS preamp and then further with the ACT2 and Premier 140. I suspect some of this comes from their adoption of the Soviet 6H30. The LP amps are back to the 6922 and my sense is that, in response to customer input they've swung back, or at least not gone even more toward the yang. The 140 should also be a great match with the Callas monitors.
Neutral tube, my personnal choices would fall into three brand camps.
European: Tron to Audio Note
American: Wavestream (Scott Franklin) to VAC
Canadian: Wytech to Coincident Technology
Note a neutral detail choice vs a more subtle neutral choice in each camp.
While not a tube pre-amp and basically not available the CTC Blowtorch struck me as shockingly neutral.
I have seen folks mention SET amps that put out only 8 watts. Amps like these are indeed great sounding, but only on a small group of high effeciency speakers. Not really an amp for the masses of speakers and not the best amp for the poster here.
VAC amps fit the bill here as well as Bruce Moore amps.
The cj premier 140 is quite neutral, but still sounds like tubes.
If you want a tube amp that sounds like SS, listen to a Sonic Frontiers Power 2 or VAC PA 100/100. These two amps combine what is NOT good about both technologies.
The KR Audio tube amps with their reverse hybrid design are very neutral ranging in power from 20-100 watts/channel (actually one version at 200W).
If you're in the market, compare the top 5 votes, and if I was a betting man....
It does depend on what you value as a listener and then of course room/system synergy.
Thanks for all the responses thusfar. Tim, you're right to be concerned about the 87 db on the speakers. I've found some amps, such as the Mac 275, to be underpowered with them. I once heard the ARC 55 watt integrated and I understand what you mean by "aluminized." However oddly, that 55 watt amp drove the speakers very well, unlike the 75 watt Mac. I've heard the Atma-Sphere talked up often. I'll have to look around for that. Unfortunately the dealers in my area don't stock much tube gear.
What about BAT, VTL and Lamm
I have a VK-75SE. I wouldn't call BAT tube amp "neutral".
is it possible that the intent is not to find a pefectly neutral tube amp, which in fact doesn't exist, but one providing balanced frequency response and sufficient resolution to satisfy most audiophiles ?
is the presence of coloration so objectionable that one would try to attain the unattainable ?
I agree, I think balance is a much more important attribute, sounds better in more applications, and causes much less fatigue and boredom in the long run. My CAT JL2 is balanced top to bottom, as is my ARS Sonum integrated, yet they sound quite different, the ARS is "warmer" to some extent, but both are balanced through the frequency range. I have no idea which is more accurate though.
Do any of 'em take in a 1 KHz and a 10 KHz square wave and output a reasonable facimile of same?
Hello Mrtennis, in fact I'm not expecting a perfectly neutral tube amp. Such a thing probably isn't desirable, never mind attainable. One of my purposes in going to tubes is to get some of that tube warmth. However, I'd like an amp that doesn't much alter the basic characteristics of the source components. I'd like an amp that is more quick and tight than the "traditional" tube sound.
If anyone has suggestions for an integrated, with appropriate power, that would be very welcome.
as i have indicated on this thread and in my previous comments, you should have no trouble finding a tube product in your price range which does not have the traditional tube sound. most amps are designed to be colorless. in my own pursuite of a vintage sounding tube amp in current production, i have not found one. this my loss is your gain.
pick an amp, and it will probably satisfy you. don't worry, euphonic coloration and bloom will not likely be the outcome of your selection.
I just started playing with a Music Reference RM10 MKII ($1950)which is a wonderful little amp and an incredible bargain if 35 watts is sufficient (I also listend to the RM9 which has a similar sound signature if you need more power). This is defintely in the neutral camp, and in the best sense of the word.
"Don't get a tube amp if you want neutrality..."
I have put my EAR 890 against 3 well regarded S/S amps with mostly non-audiophile people. The EAR won every time, most recently with my brother and sister-in-law who don't know the difference between a tube and transistor. After 2 hours of going back and forth they decided the tube amp was the most musical. This was hard for my brother who loved the appearance of the S/S piece. He thought the giant heat sinks were the coolest thing ever seen on a piece of electronics.
Not sure what people are saying when claiming no tube amp can provide "neutrality". Kind of like entomologists who, for decades, claimed bumblebees should not be able to fly based on scientific understanding of physics and flight. They recently discovered why but for years held bumblebee flying as a mystery. There are many tubes amps that musically soar on a regular basis.
I think you will find much fewer folks saying tubes don't soar, than folks claiming tubes are neutral. But I think Mrtennis is right that there is some convergence between SS and tubes with tubes becoming more neutral, much less obviously colored than in the past; they have always been enoyable and sometimes more obviously so than SS IMHO.
The reason tubes are accused of being 'warm' is that they more closely follow the rules of human hearing than do transistors. If neutrality is your goal, and on top of that listenability, due to the constraints of the technology tubes are the only game in town.
Some important rules of human hearing are:
1)Loud sounds mask quiet sounds
2)loudness is detected by the level of odd-ordered harmonics
3)speed can invoke emotional response, slowness often invokes intellectual response
4)ears hear on a logarithmic scale, thus 'decibels'
5)bandwidth is roughly 20Hz to 20KHz.
6)sound location is detected by phase and time
a couple of examples:
Distortion masks detail, which is why SETs can sound more transparent and detailed than a transistor amp (if the speaker is efficient enough to take advantage of the low-power range of an SET).
Getting rid of negative feedback can reduce harshness (rule #2 above). Nelson Pass has shown this in his 'First Watt' amps, and tube guys have known this for a long time.
While no amplifier will ever be 'perfect', the more the rules of human hearing are obeyed the more the result will be an amplifier that is the most neutral while simultaneously being the most musical.
Don't most tube amps take on the general character of the tubes so they generally do not have their own sound.
Eagleman6722, could you clarify what you are trying to say?
Eagleman, if that were so, you would have the famous wire with gain, which is a goal which perhaps designers strive for, but hardly ever reach. Tubes can colour the sound and tube rolling may sometimes even improve the sound of a device, but often enough they just change it and not necessarily for the better.
See Atmasphere's remarks above....
Based on my experience, I would recommend you audition Rogue Audio's Tempest II. I went from Simaudio's i-3 to Rogue separates, the Perseus and the Stereo 90.
I found the Rogue combo added more texture and dimension to the music while being "more neutral" than the very few other tube amplifiers I listened to in the <$1500 dollar range (used).
Besides few other choices that have been already mentioned, I would like to throw -in just one more brand in this mix-up. My favorite amp (yes, I know - I am bias, on that matter) Consonance Cyber 800. It is a 78wpc El34 base monoblock design within reach of most audiophiles.
It is not the best amp out there.........but it is good enough for me. Right now, I have placed it in the hands of a person that will perform some mods on it to get the most out of it...........will see what will that bring to the table and how it will affect its performance .
I would just like to add that as good as Cybers are there are not the last word in transparency and it may luck some body on string instruments. However It could be the limitation of my speakers. At this moment I am not a 100% sure. I am hoping that treating the input stage, some silver wiring and addressing few other areas where improvement is possible will answer my question.
FWIW the idea that tubes color the sound has the same merit as the idea that transistors color the sound. What colors the sound is anything to do with audio reproduction- IOW it is not a tube/transistor thing...
Ralph, I did not wish to imply that tubes add a coloration to the sound. What I should have said is, that tube rolling will INFLUENCE the rendition of music of a given component. When I wrote my post, I forgot for this moment, that "colour" is detrimental to the concept of "neutrality", which to my mind is a very subjective and unclear concept anyway, as any practicing musician knows, who can voice or tune his instrument in many respects to best fit the character of a given piece of music, just as a designer will voice his product to what he feels fits his concept of musicality best.
And - as you say- of course this is certainly not a tube/transistor thing. I never meant to imply that.
Hi Detlof, got it!
I play in a couple of bands and I know what you mean there. But as a designer, I do exactly the opposite of what I do in the band. IOW, I try to make the equipment do as little messing with the signal as possible.
Atmosphere- I am saying that a tube amp takes on the sound character of the tubes that it is running. In my experience, ( which is very limited), changing tubes seem to change the sound on the same tube amp to where you really cannot detect the sound character(thin, full bodied, warm, bright, etc).of the amp itself. It seems that other things like soundstage, imaging, holographics are more the character of the amp itself. Maybe I am all wet but, based on my experience, I can't imagine a "nuetral' tube amp because of the wide range of tube flavor. Hope this helps. .
I've done a lot of tube rolling in my time on various preamps and amps and as I said before, it does have an effect on the sound, sometimes tightening the bass a bit, opening up the midrange slightly, or sweetening the highs a tad, but the effects are subtle at best. What I have never heard, was a total change of "character" of a given device. A case in point were the Jadis preamps, which had an euphonic sweetening of the midrange, not unlike certain Koetsu cartridges, which could be seductively beautiful sometimes, but certainly were a colouration away from neutrality. We've tried our best - at a time when good tubes were more plentiful and less expensive - to get rid of that sound ... and failed. Another case in point, this time with Jadis amps, were the KT90, where you could trade more slam with a tiny loss of midrange solution, that was audible, but certainly did not change the general voicing, or character of the amp. (Jadis Defy)
Besides, there are myriads of amps these days, which use identical tubing , but certainly sound very, very different. So basically, in my opinion, it is the design and quality of parts which count. The choice of tubes play a part, especially their lack of tube noise, also the choice of tubes within a given design, using the tubes capabilities vis a vis the rest of the design. Sometimes an amp is built around a certain tube, like the Zanden 9600, which is built around two 845s. But the idea that all 845 amps would sound like a Zanden is simply so far from reality as the idea that I could change the sound of this amp with swapping 845s
around. I've tried it, and it is just not so.
Again, and maybe I'm wrong, to my reasoning, only if an amp's design is absolutely neutral, just like the proverbial "straight wire" and where the "gain" were just delivered by the tubes and nothing else, the argument would hold true, that it is the tube which makes for the sound of the device. I'm not an expert, just a long time user, but I doubt if a component like that exists. Rather I would submit, that it is the total design, be it tube, transistor or hybrid, which makes for neutrality of an amp or a deviation from it.
Thanks Detlof, I am not an experienced tube Amp user and, appreciate your insight here.
Eagleman6722, if you look in the DIY forums, you will see that people are commonly swapping op-amp chips out in their equipment and projects because certain ICs have a 'sound' they are looking for or trying to reduce. This is not a tube/transistor thing, its simply a component thing.
IOW you can no more say a tube amp has the character of certain tubes than you can say that a transistor amp has the character of certain transistors (or ICs.). The only thing is, in tube amps, they are a hell of a lot easier to change :)
Any amp made by Leben will make you realize that "warm, tubey sound" is a cliche.
Not only a clichè but in most cases a thing of the past!
A thing of the past? And why not? When you listen to the Leben, you wonder what new technology has added to realistic sound? Turntables are old technology! Yet, look at the resurgence.
I own the Leben CS600 paired with Rogers LS3/5a (15 ohm) and I can tell you the sheer musical experience is wonderful!
Denjo, what I meant was, that the idea that tube amps were warm and coloured was a thing of the past, not tube amps per se. I have nothing but tubed gear in my rig.