Rich; organic true balanced amp w good detail $6k

Suggestions welcomed & appreciated- here are the Criteria:

- fully balanced architecture
- rich, organic sound, extended bass, silky highs, but not at the expense of obscuring detail
- No OTL (too many tubes/heat)
- SS (Class A bias) or tubes OK
- 20-200 wpc ok, the lower the better though all things being equal- well built power supply crucial
- stereo amp easier to put on my Sistrum rack, but mono-bock architecture also considered if better performance
- $6k or less used would be ideal, but would consider up to $8k used if there are no world-beating contenders at the $5k-$6k used price point

Preamp is a modded Sonic Frontiers Line 3- extremely neutral, hence the desire for a richer-sounding amp to balance. High efficiency speakers from Coincident- large open concept room (main floor of house). Re: tubes, have used ARC VT-100 MKIII- good- airy w big soundstage, but meatier mids would be better. Also had Wyetech Topaz 20-watt SET, superb, if slightly lean in the mids (and not fully balanced, but shows you how powerful 20 watts can sound with a well-built power supply) For SS, am considering Pass XA.5 series (they now can run balanced from what I understand?); Clayton Audio M-200 (but unfortunately over the price-range).

Thanks in advance for any suggestions- I have an open mind, so bring it on!
Interesting, it sounds like we are looking for similar amps. I've also been eyeing some Clayton M-200's and Pass XA-60's. I did just pick up a BAT VK-75SE, and it sounds very good. It actually even had my wife saying positive things (very, very rare). I'm not sure if I'll keep the BAT yet though, as it throws out a tremedous amout of heat. I have to find a way to better control the heat dissipation to consider keeping it though. The BAT's sonics do have me leaning toward a tube amp though. I would love to hear a pair of VAC Musicbloc 160's. From my previous experience with BAT & VAC gear, I would imagine that the Musicbloc's would have more silky high's, while the BAT would have better bass. The VAC slightly lighter, the BAT slightly darker.
I'd also be interested in hybrid amps like the Aria WT100(XL), Aesthetix Atlas, or Blue Circle BC204, though none of these show up on the used market much.

FWIW, I'm currently using a ARC Ref 3 preamp.

Happy hunting,
My vote is for a used VAC Phi 110 if you can get your hands on it. Otherwise, Musicbloc, or VTL MB 125, 185, 450...
great ideas so far guys- I think we on the same page

John (Jmcgrogan2)- what are you using for speakers; preamp; and what is the size of your listening room? Also- have always been curiuous about the '2' after your Agon name- was there ANOTHER Jmcgrogan already? :-)

Dennis- yes, have heard great things about Vac, but have never heard them myself. What is the best VTL amp? I heard the 250's running in triode mode are very good, but also that the Signature models have the best sound, and some feel that you need to get to the 450 Sigs to get the best VTL offers...
$6k (or less) will buy a pair of Belles 150A Reference or 350A Reference monoblocks. In my system, they have the characteristics you mention. I sold VAC 160 Musicblocs in favor of the Belles 150A Reference amps.

Associated gear is: Atma-Sphere MP-1 MK III preamp, Silverline Sonata III loudspeakers, Modwright Sony 999ES Platinum Signature with tube power supply.
Since you said Organic I'll suggest Lamm ML1.1's or Lamm M1.1's used as the $7-10k used depending.. They can be a little dark but not like the BAT's.. Way more musical than anything listed so far. The Lamm's are single ended though with balanced inputs.

The VTL are very liquid and open (nothing obsured or blurry) but with slightly more emotion than the ARC you are using. I think you have to go to the VTL450 or higher to get fully balanced (Remember 3 times the electronics path for fully balanced designs).

If you wanted a more romantic sound go with the Manely 250's or 500... Manely errors on the more traditional side versus the clarity that the VTL provides. You might be able to go with his smaller amps which are a single ended design.

The bargain amp would be a Music Reference RM200 or the new RM300's.. these are really easy tubes to deal with (only 4 output tubes, long lasting, balanced design) Not Warm, the RM-9 MKI or MkII are warmer and excellent amps also. Less heat also because Roger doesn't drive the tubes hard..

I have owned two Sistrum racks and I found that in a very revealing system they start to strip away some of that magical midrange as a trade off for the detail and image placement. Throw a 1.5" maple cutting board under your preamp on the upturned Sistrum spikes and see what you think... Plus make sure yours are filled with the microballs to mass load the rack.
What's the output impedance of your preamp?
Hey Sutts, yeah, believe it or not when I tried Jmcgrogan I was prompted that the name was already taken.......makes me wonder if I signed up before I knew I did, or if there is another Jmcgrogan....perhaps and evil Jmcgrogan??? So I'm stuck with in Jmcgrogan 2 channel. :)

Preamp is the aformentioned ARC Ref 3, speakers are Verity Auido Parsifal Encore circa 2004. Listening room is 24 X 14 X 9. Musical preference is jazz/blues/rock/folk/classical.
Main source is vinyl (Basis/ZYX/Walker), then digital (Marantz SA-11S1 w/ Ultimate mod from Underwood/pcX)

How about the moscode 401HR;200 watts per channel, a 30 day in home trial period, it lets the owner do a lot of tube rolling that should not break the bank. The only requirement it does not meet is it not a balanced amp.
Bob_reynolds: Good Point about the output impedance of the Sonic Frontiers.. it might not match up with the Lamms as they are really sensitive. Typically less then 1volt to full volume
Belles amps are what you are looking for. His new monoblock amps are said to be his very best and sell for $6700 new for the pair.(Model --200) They are pretty small and run cool so they can be stacked on your rack.

They are said to sound better then the Reference line which in my experience proved to be some of the finest sounding amps I have heard.

The Belles M200 monos are getting lots of positive buzz. However, they are single ended only.

I mention it because the OP requested fully balanced as a prerequisite.
well guys- just got home from the gym, and listening to one of my fav's- Pharoah Sanders Quartet's (what a great tenor sax player) double-disc 'Crescent with Love' on my 2nd system (47 labs digital; recently acquired Air Tight ATC-2 preamp- talk about suave & velvety- time to pour a glass of California Cab and chill for a while...)

Tvad- yours is a system I would really like to hear- in fact, one other company my speaker designer said he respects is Silverline, and I understand Ralph at AS makes a great preamp. Perhaps the Belles is worth checking out- there is definitely a loyal legion of fans, however am not sure if they have a model that is fully balanced- will have to look into that. The fact that you replaced a set of Vac's better amps says something...

Cyto- thanks for the tips on the Sistrum 'tweaking'- I will check into that- up here in Canada we have good access to Maple :-) Hey- GREAT recommendation on the Lamms! In fact, a good friend of mine now has M1.1's to drive his newly acquired Verity Parsifal Encores. He has always had a Lamm L1 preamp, and to say he is loving the new setup/synergy would be an understatement! Re: VTL, it sounds like the 450 Sig's would be the way to go. I am only slightly hesitant due to re-tubing costs, as this system also doubles as a 2-ch HT setup for movies, etc., so it is on a LOT- if I go tubes, as long as they are run conservatively (as in my preamp), then that's ok I guess. Manley- have not heard them. Music Reference? That sounds interesting- have you heard them, and what did you feel was their best amp(s) sonically?

Bob_reynolds- I believe the output impedance to be 50 ohms for the unbalanced outputs, and 78 ohms for the balanced- would this affect anyone's recommendations?

John (will the 'real' JMcgrogan please stand up :-) another great system- that vinyl rig must sounds sweet, and I like that room size! Almost the perfect 1.6:1 length to width ratio (I think Cardas talked about that).

Grannyring- another Belles recommendation- wow- they seem to be the winner in my little poll tonight! I will try to check them out, but I have never come across them up here in Toronto.

Thanks again guys, and keep it comin'! Btw- while riding the bike at the gym, I was fascinated by the Democratic Presidential candidate debates. I am Canadian, but find this an interesting race- Hilary seemed pretty composed tonight, and answered questions in a multi-faceted way. Is it just me, or did Edwards seem to 'team up' a little w Obama...
Sutts, the Belles 150A Reference and 350A Reference amplifiers only work as monoblocks when their balanced XLR inputs are utilized. I assume this means they are fully balanced in this configuration, but I could be wrong. I don't know the difference between your definition of fully balanced and Belles' definition of balanced.

Most listeners who have heard the amps both as stereo amps (single ended only) and as monoblocks agree that the monoblock configuration is superior in all respects.

BTW, if I had the dough, I'd own Lamm 1.2 monoblocks...
Tvad- have you heard the Lamm's up against the Belles? If not, regardless of the comparison, what are your sonic impression of the Lamm 1.1/1.2 amps? I think my buddy got his Lamm 1.1 monos for just over $7k USD used- from what I understand a good deal...

Hey- I was just reading up on the 150A ref's- they seem like a great choice- how hot do they run though, and are they meant to be turned off when not in use? Do they do texture like tubes?
I've owned Lamm M1.1's and M2.1 and my friends fell in love with them but then I heard the VTL S400 releasized I needed some more clarity and also surpising the VTL went lower and deeper and it was definitely tighter.. I can't imagine the Belles comparing to the Lamm's as they are really addictive and some day I'm dying to get a set of Lamm ML2.1... If you run the Lamms in a home theater setup you better drop the center channel because there is no way you will find a matching tonal center channel amp... run Phantom Mode..

Sutts: The Lamm M1.1 versus M1.2 ..yes the M1.2's are better (not in a huge difference as he just used more currently available parts) and they provide like another 10 watts a channel. The biggest advantage are they are newer (since these run in Class A full time) Expect to see them listed for about $6000-7500 for Lamm M1.1's and somewhere north of 10k for M1.2's. Oh yeah and buy the 6922 input tubes from Lamm as they were like $25 each from them.... total no brainer bargain..

As far as the VTL amps.. 6550 tubes from VTL are about $60 each but you can get between 5,000-10,000 hours I out of tube the way VTL runs them... plus the best part is no matched pairs,quads, octets.... so way cheaper than ARC retubing... one tube blows, just drop in another. The new VTL450 signature has the computer controlled biasing which is awesome... similar tech to the S400 stereo amp. VTL no problem for home theater...

As far as Music Reference amps... I have owned the RM200 twice and I still regret selling it.. it's not as organic/seductive as the Lamms but it's more open on the top and crystal clear with even 2ohm control.. it only requires a Quad of 6550, or KT88's tubes which I recommend buying from Ram Tubes (Music Reference's company) especially the input tubes because they DC stress them which no one else does .. Music Reference amps aren't hard on tubes and tube that would be noisy in other amps are quiet in the RM amps.. The older RM9 required more expensive Matched Quads to achieve 100watts a channel or 125watt a channel in the RM9 MkII. These don't have the iron fist control of the RM200 (which can borerline on sounding similar to the high end SS Ayre amp in clarity and control) This might be similar to the Vac with the sparkle, and also without the constant repairs my friends have had with their VAC's (they sold them now and went back to solid state... after 3 roundtrips back to the factory..) Music Reference.. no problem for home theater.. Check out Audiocircle dot com for the Music Reference Forum, I'm sure you can post and find someone near you to hear these amps.. very minimalist but bulletproof design and they sound great!
I have not heard the Lamm amps in direct comparison with the Belles, but I would expect the Lamm amps to sound better...they ought to at more than three times the price. Please note I was referring to the Lamm hybrid design, and not the Lamm SET amps.

The 150A Reference amp and 350A Reference amp run cool. I have owned each, but I have only owned a single 350A Reference whereas I own 150A Reference monos.

I have been told that the Belles amps are meant to be left on, but I turn mine off each night. Energy consumption guilt. A couple hours of warm up gets them up to optimal sound, IMO.

Do they texture like tubes? That's a tough question. No solid state amps that I have heard sound like tube amps, but they do some things better than tube amps I have owned. The strength of the Belles amps is their tonal balance, sweet top end, bass control, and resolution.

The VAC tube amps I have owned were stunningly clear and holographic. However, they were not as tonally balanced and their bass, while excellent, was not as deep and solid. I also would not characterize them as warm because their top end has so much sparkle.

The designer of my Silverline speakers recommended Belles (or Pass Labs) amplification, and he was correct IMO. Have you asked Israel Blum what amps he would recommend for your Coincident speakers?
Cyto- thanks for the thorough comments/comparisons- didn't realize the VTL amps run their tubes that conservatively- a good thing. Question- you indicate the 'new' VTL450 signature has computer-controlled biasing. If one is buying these used, how 'recent' is this change? Also- are the 450 Sigs not 'room heaters'?

Tvad- thanks for Pass reco- was also thinking of their 30 watt XA-30.5. As for Israel, we talk often- he lives 10 minutes from me! There is no point though in even mentioning SS to him- he is a tube guy through and through-preferring SET's mainly...
Tvad: Great descriptions of those amps!
The Music Reference RM200 would have the clarity of the VAC but without the sparkle (very neutral, might not have enough flavoring for you), the RM9 with EL34's would be a little rolled on top and bottom, but the RM9 with 6550's would have better bass and more top extension but not as romantic in the mids (not as clear as the VAC's) (but not as tight as others or including the RM200 which is like SS on the bottom end).

I looked up on VTL's website and it looks like they have listed the newer version of the VTL450's which have some of the computer control circuitry in them for biasing. Maybe at CES this week it will be official or they will update the website. The S400 constantly bias during listening..As for heat... 16 6550c across two tube monoblocks generates a heat anyway you cut it, but in my small 16x12 room my lamms would heat the room 10 degrees in under 5 minutes.. Class A or Big Tube amps.. both are probably pretty close to the same heat output..

Your speakers are pretty effiecent and provide a high ohm difficult load that you should talk with the designer like TVAD suggested and find out what he recommends. The description TVAD makes for the Belles sounds like how some people descripe the Clayton equipment which I haven't heard.

Congrats on being able to make this kind of equipment choice... as this is the range of $$$ that products can be amazing across the whole frequency spectrum.

Some times Lamm ML1.1's show up which are 90watt tube amps (not hybrid) (not SET) and I'm sure they are amazing at approx ~10k and sometime 6-8k for the older ML1's. Don't buy Lamm's unless the owner has the original crates to protect them with otherwise you will have problems shipping them to Lamm should you need service.
Sutts, about the Pass, how much better do you think the XA-.5 series is? I ask because you will not find any used ones here since they are so new. I was thinking that many will now be dumping their XA's in search of XA-.5's. It would seem to me to be a good time to be looking for the XA's. You may be able to get a pair of XA-60's for the same price as a XA-30.5. Just a thought.

BTW, only the Belles MB-01 is biased into Class A, and it doesn't say if it's fully balanced or not. The Lamm's are very good, but I believe they are single-ended as well.
Here is a quote from the Belles website regarding Class A.
The key to accurate audio reproduction is the ability to resolve detail. To that end, David Belles has designed his first class A amplifier in 30 years. Everyone knows that class A biased amplifiers represent the pinnacle of what is possible in amplifier performance. However, designing and building a class A amplifier is no easy task. The first amplifier that Dave Belles designed more than 30 years ago was an class A amplifier known as the Belles A. Since that time, Dave Belles has learned what it takes to produce a truly great class A designed amplifier.

Class A design requires attention to tolerances, heat needs to be dissipated, power supplies need to be sufficient in order to produce an amplifier that does not compromise performance. The amplifier's power rating needed to be carefully selected in order to produce a unit that would drive most speakers at sound pressure levels that are satisfactory to most users.

Class A design is the best, regardless of what anyone would try to tell you.

I believe the VTL MB-450 Series II Signature with controlled bias is quite new. It was just reviewed in the Jan/08 Stereophile. I believe the reviewer (MF) had some issues with the biasing circuitry. Yes, I've been watching those too. Read the section entitled 'A Matter Of Reliability'.

FWIW, I have heard the Clayton amps. I used to own a pair of M-100 monoblocks. Very nice indeed. Possibly the best SS amps I've ever heard, and I've owned a few more expensive ones. The one nit I had about the M-100's was a low level transformer hum that I could not get rid of. I spoke with other Clayton owners who had similar problems.
I heard the new M-200's have new transformers, so hopefully Wilson has solved this dilemma.

I have and really like VTL 450s from a few years back (no autobias and different caps than before). I think they are great. However, if you have high-efficiency Coincidents, the 450s might be a bit of overkill (like they are with my speakers). The Coincidents are reasonably benign loads as well so I think you could get away with less "beef."

Another couple of amps I can toss in the mix if you can find them used would be EAR 890(s) or EAR 861(s). They are both stereo amps which can be bridged and used as monoblocks. The 890 uses a KT90 tube and the 861 uses a EL519 tube (originally a TV set tube) in "enhanced triode mode". Both amps (and almost all EAR amps) have quite beefy transformers. They both have true balanced inputs, both work in Class A, both are quite easy on their respective tubes (the EL519 has a VERY long life) and both amps are very easy on the user (autobiasing, very little to do, long tube life).

If it were my choice, I might go for a PAIR of EAR 861s (which, when bridged, would put out 64W per channel). They have no feedback, are extremely linear, and I find the midrange and highs to be absolutely wonderful with this tube and depending on which Coincidents you have, you might be able to get by with a single amp just fine (the 890 would be no problem as one amp is 70Wx2). If you found them used, they would probably be in the price range for two (ditto for one 890). And in any case, you could get one, use it, and if you decided you needed a bit more oomph later, you could get a second. I love the tube...
Manley makes sweet sounding amps that can be run in triode or tetrode modes. I would say with your set up triode would be what you're looking for. A lot of amp for the money.
Jmcg- yes, re: the Pass, I don't believe the XA-60 is balanced, but I could be wrong- I only know the newer XA-30.5 is. Belles MB-01? Hmmm- any writeups on this one? As for the VTL 450- I am sure the newer version would be mucho denaro $$$! You had Claytons? cool- it sounds like the new M-200's would fit all parameters except for cost ($9,500 new). One amp everyone seems to agree on though are the Lamms.

Rleff- have never heard Moscode- is it also a true balanced design? Do they have lower powerered versions, and how would you describe their sonic signature?

T_bone- EAR- yes! Have heard some great stuff about that guy's products. I will have to see if they have a Canadian dealer somwhere- would really like to give them a listen- would the 861's be the sweeter-sounding of the two? (compared to the 890)

Apache- yes, Manley was mentioned earlier- good thought, but am not sure if they run balanced, and how hard they are on tubes, in fact not even sure which are their best models.
I listened to the 401HR on my friends soundlab a3's and was very impressed.Moscode is a tube hybrid rated at 200 watts per channel;listening to the A3's there was a large soundstage,excellant bass control and the strings seemed just natural to me (proper timbre I guess).
I have soundlab m2's and was going to buy one of these myself except I decided to try the OTL experience;if I was going another direction the Moscode would be on my short list.Moscode website is;the only spec that it does not meet as you listed is it does not have balanced inputs.
Personally, I would choose the 861 (or the pair). I own an 859, which uses the same tube (also has beefy transformers, ETM output, sounds so silky smooth it is ridiculous, alas has only 13.5 watts and I need more) and I love it. The 861 is basically a larger ('push-pull') version of the 859. They both sound wonderful. The 869 (1-2 watts more than the 859 but otherwise almost identical) is also good.

I happen to like Tim de P's circuits. He doesn't use feedback much, he likes trying to get SET 'taste' with more power and is willing to experiment with circuits to get there.
excellent advice- thanks again everyone for the thoughtful and informed responses & recommendations- it's been a LONG time since I started a thread in this forum, and you guys have not let me down- I will look into all of the suggestions- cheers.

Sutts in Toronto
Sutts, with your Coincident speakers, I'd go with Israel's suggestion and use tubes. Given a choice between tubes and solid state, I'd choose tubes as well, but solid state seems to work better (or more to my preference) on my Silverlines.

There is value in following the advice of the speaker designers if they are willing to be specific with their recommendations, IMO.
Tvad- can't argue with you there- only 'Izzy' as I call him will point me to an SET, but then his priorities are only music listening. This system is on my main floor, and is used a lot for movies as well, so a bit more power and a lower noise floor is nice (hence the 'quieter' fully balanced advantage). *All that being said though, if I hear something that really blows me away, I will overlook some of the criteria for the resulting sonic benefit. I am going to investigate these Belles 150A Ref Monos you suggested- are they full enough sounding in the mids?
They are full enough in the mids to suit me, but the ultimate sound will be determined to a large extent by your preamp and speakers. Buy a used pair and resell them if they're not to your taste.

BTW, your description of what you want seems to correspond with what I have read about Monarchy SE-250 monoblocks. Check out the review in the January 2008 edition of Affordable Audio.
Sutts, you are starting to confuse me. It seems like some recommendations are dismissed because they are not balanced (Pass XA-60, Moscode, Manley,etc.). While other single ended amps like the Belles, Lamm and EAR intrigue you. A little help here?
For me, true balanced is a must. My digital front end only outputs balanced, my preamp is fully balanced. Personally, there are enough fully balanced choices out there that I do not see the point in breaking the chain. YMMV.

BTW, the Clayton M-100's that I owned a while back are NOT fully balanced, but do offer balanced inputs, like VAC, EAR and others. The newer M-200's are fully balanced though. If these really interest you, you may try contacting Jonathan at Goldman Audio. He has mentioned to me that he has a demo pair for sale.


01-07-08: Jmcgrogan2
While other single ended amps like the Belles, Lamm and EAR intrigue you.
Haven't we established that the Belles and Lamm amps are balanced, or are you discussing fully differentially balanced versus non-differentially balanced? Also, it has not been established whether Belles or Lamm monoblocks are differentially balanced or not.
Thanks John- sorry if any confusion caused- I will admit being curious as I have not heard the majority of the recommendations, but have read good things about several of them. Staying the course for true balanced would be ideal though, and the Clayton is the one that intrigues me the most- thanks for the dealer tip.

Tvad- Monarchy? I believe they also make an SE-160? Have you heard the Monarchy amps up against anything else?
Sutts- Maybe the power requirement for deep bass (esp. w/HT) can be met via the subwoofer amp, running your mains hi-passed and/or with mains and center set for small via the processor.
Sutts, I have not heard any Monarchy amps...only read about them. The descriptions of them seem to echo your requirements, so I brought them to your attention.

The Belles amps are transparent/neutral. If you're looking for forward mids, then they are probably not for you. However, I still believe they would be worth trying in your system if you can make a good purchase on a used pair.

Also, a push-pull tube amp run in triode mode would provide the mids you seek, however the bass will generally be a bit fuller and looser than the same amp run in pentode mode. Still, there are several good push-pull tube monoblocks that offer both pentode and triode operation and would provide plenty or power for the Coincident loudspeakers. You could run them in pentode when watching movies, and run them in triode when listening to music.
Sutts, you should also consider Ayre amps, fully balanced and lots of power for the low end, yet gorgeous "tubelike" sound. I have owned only the V3 but was extremely impressed with its performance on a no. of different speakers. Now I use the ARC VT100 Mk III but could gladly return to the Ayre if I wanted to eliminate the hassle of retubing and biasing.
Tvad- I am a previous fan of PP triode amps, and would gladly return to that option as well. What are some of the better PP triode amps you have heard? I had a older pair of modded altec 1570B's that were very good...

Sc- there is a local dealer for Ayre- which of their amps would sound the richest in the mids?
I owned a VAC Phi 110/110 which was outstanding with Von Schweikert VR Gen III HSE loudspeakers.

Also look into the Bella Extreme 100 monoblocks. I haven't heard them, but again they have received some nice comments from owners and at least one reviewer.
Haven't we established that the Belles and Lamm amps are balanced, or are you discussing fully differentially balanced versus non-differentially balanced? Also, it has not been established whether Belles or Lamm monoblocks are differentially balanced or not.

I'm under the assumption that we are talking fully differential amplifiers, as the OP's first requirement was "fully balanced architecture", which I took as fully differential, not just balanced inputs. AFAIK, Belles and Lamm are not fully differential. The Belles MB-01 does run in Class A bias, which is what Sutts was looking for in SS, but in the Belles literature it only says that the MB-01 accepts fully balanced inputs, this does not mean that the amp itself is fully balanced.

Again, I know that fully balanced does not necessarily mean it will sound better, however, I do understand that if you are running a fully balanced system, it doesn't matter if you break the chain. A fully balanced source and amp won't run fully balanced with a single-ended preamp. Similarly, a fully balanced source and preamp will not deliver a fully balanced signal through a single ended amp.

There are many designs out there that have balanced inputs and outputs that are not fully differential designs. I guess it just comes down to is it a requirement for Sutts, or just a plus. For me, balanced is a requirement, for now. Just as if I go single ended in the future, buying a fully differential design would not be cost effective. Since it does cost more to do a fully differential design well, it would add no benefit if the other components are single ended. Just my $0.02.

Sutts has not mentioned (unless I overlooked it) if his source is fully differentially balanced, so the point may be moot.

I use a fully balanced source (turntable) and an unbalanced source (CD player), which pass their signals through a fully balanced preamp. Both sources sound excellent, or not so excellent, depending on the recording. I do know that those who have heard the Belles amps in their single ended stereo versions and in their balanced monoblock versions universally report that they are more resolving and produce a larger image when run as balanced monoblocks. This would seem to be in keeping with a lower noise floor inherent with balanced operation.

I wonder if the discussion about balanced versus fully differentially balanced is more rhetorical than practical? For the purposes of this discussion as it relates to Belles and Lamm, I suppose it'd be valuable to determine which definition of balanced applies to their amplifiers.

...and whether it truly matters to Sutts.
Sutts, if you have the opportunity to audition some Ayre amps, listen to whatever the dealer has on hand. I think you will find they are ALL excellent. The $$$ MX-R monoblocks are incredible but out of most people's price range. The stereo amps V5xe and V1xe are great performers as well. Hopefully you can audition them with your preamp or best of all at home in your system. I have never heard a speaker that didn't sound great with Ayre--but I have only heard what my dealer sells, Thiel, Vienna Acoustics, Linn, and Maggie.
I suppose it would be up to Sutts. As for me, I could very easily live with the Lamms, they are fabulous amps indeed. I could not say this about Belles though. I had a friend lend me his Belles 350A for a few weeks, a couple of years ago. Very clean and articulate, but rather thin and edgy sounding to me. My friend agreed and sold the amp about a month after I returned it to him. Maybe the newer Belles gear is better, and worth another listen. I wouldn't buy one, but would certainly audition one again if possible.

It's funny how we all listen to the same gear, but have different impressions. As Sarah (Sc53) mentions that Ayre has a gorgeous tube-like sound to her. I've heard Ayre equipment on several occasions (not the MR-X's though). I do agree with her assessment that they have lots of power on the low end, and would even add that they are dynamic, extended and transparent. However, never once when listening to Ayre gear did I ever think 'tube-like' all.
It's all about system synergy and personal tastes I which case, you're on your own Sutts....sorry.

I have owned the Monarchy SE160's twice! I loved them and the mids are wonderful. I would say the mids are certainly more forward compared to Belles. However on my Dali Grand speakers and paired with a very good tubed preamp the Belles 350 Reference amps just ran circles around the Monarchy amps in terms of resolution, bass control, power, stage size, purity, highs were far more extended, far better speed and pace.

The Monarchy amps also caused a horrible thump in my speakers making a loud noise and pushing the drivers out when turned on. That is common and usual for the SE160. I got used to it, but it took some time.

I ran two Belles Ref 350 amps for a little while and the sound was effortless and beautiful. I just could not affort two 350's at that point in my life and settled on one for awhile.

I have always liked the sound of Hybrid amps owning several Blue Circle amps and the Monarchy's. When I found the Belles the Monarchy's were quickly sold.

I now own a Canary CA 309 modified to be very close to the newer CA339. It is a 45 watt per channel 300B push/pull monoblock amp. They would be glorious on your speakers, but are not balanced and you have to manage 8 - 300b tubes! Yikes.

The Belles 350 or 150 Ref's as monoblocks would be very good. The new Belles MB01's are much more expensive then used 150/350 reference amps, but I also hear they are as good as it gets at any price.

I don't want to manage all the tubes in my Canary amp, but they stay until I can find a hybrid or SS amp that is as musical. I am trying a Butler 2250 next. 250 watts in a unique hybrid design.

If Monarchy fixed the turn on thump problem with the SE250, then it may be worth trying. More power is also better as the SE160 drove my speakers more like a 75 watt SS amp.

For P/P, Class A, Triode, the CAT JL2/3 are in the first rank. CAT eschews balanced operation.
I guess I better chime back in here on the balanced thing. The preamp is definitely a true balanced design, as is the dac. So ideally, it would be nice to maintain this all the way through, hence the original criteria. However, if another contender appears that is truly more musical and synergistic, and is NOT a true balanced design, I will consider it.

Tvad- good comment on the rhetorical vs practical re: the balanced viewpoint. In fact, I spoke to my buddy tonight with the Lamm M1.1's. There is a balanced in, but he nor I are sure if it is a true balanced circuit, I suspect perhaps not, it is simply an XLR connector- someone please correct me if I am in error. From what I understand, the new Clayton M-200 monos are a true balanced design, but I will get this re-confirmed. In fact I spoke to David Belles today, who strongly recommended his new M200 monos, however they are a single-ended design...

Sc53- re: Ayre, I remember now hearing it once at a local dealer, and would agree with Jmcgrogan2- dynamic extended and fairly transparent, however there is no way I would compare them to certain tube amps I have had- a good recommendation though none the less, and thank you for joining the thread!

John- interesting- you're the first one to mention 'thin & edgy' re: the Belles- hmmm- that has me worried a bit... But no, I don't feel I am 'on my own'- all of the help here has been great! thanks again for continuing this thread with me.

Bill- there is just something about the Monarchy that doesn't put it over the top for me, and I can't explain what, but understand that they are limited in certain ways from a bandwidth perspective, and I don't feel they would be the 'end of the line' for me... The Canary recommendation is interesting though- in fact, Israel of Coincident was selling some of them for a while to his customers, especially the 339's- they did have a nice full-bodied quality to them, but of course single-ended, and the tueb replacement costs scare me!

Maybe I need to get out of town and go hear my buddy's Lamm M1.1's and that may convince me to save up and wait for a used pair. There is another dealer an hour or so away that has the VTL 450 Sigs- if they have a triode mode, as my buddy led me to believe, that could prove enticing. Well- thanks again everyone, fantastic recommendations all round!
Sutts, we need John to verify if the 350A he heard was the Reference or the older standard 350A. Goodness I have owned to many amps, but the standard 350A I did not like. It was thin to my ears. The Reference 350A has much more body and weight. It soars higher and smoooooother.

Funny you own the very speaker brand I am looking to mate with my Canary amps. I would love to hear my Canary amps on a high effeciency speaker. Mine are 4ohm and 90db effecient - not an easy load for a tube amp. I may try a Paul Speltz Zero autoformer so my amps see an 8 or 12 ohm Dali Grand.

01-07-08: Sutts
I guess I better chime back in here on the balanced thing. The preamp is definitely a true balanced design, as is the dac.
Is your transport also fully balanced?

If the Belles 150A Reference monoblocks were thin and edgy in my system, then I would not own them. Also, be aware the 350A and 350A Reference are different amps. It's not clear to me which version John heard, but in any case it was apparently auditioned in the single ended stereo configuration, and not in the monoblock configuration running balanced. It makes a difference, but perhaps not in the overall tonality given the associated gear with which it was paired.

BTW, are you aware the 150A Reference in monoblock configuration is rated at 500wpc into 8 ohms and 1000wpc into 4 ohms? Plenty of juice to blow up your Coincidents.

Three inputs on the Lamm.
Pin assignment:
pin 1 = signal ground;
pin 2 = non-inverting input (+);
pin 3 = inverting input (-).

The amp must use a shorting plug on the inverting input if not using XLR input.

The amp is the end of the chain when it comes to differentially balanced or not, and if there is anything to the "SET" nature of your amps, it will not matter a great deal I expect. I am not a circuit specialist, but given the way that the circuit runs through the tube, I cannot imagine how the "fully balanced" will matter to a true SET - I imagine it will only matter if it is triode-ified push-pull, and even then, circuit implementation will matter far more than whether the amplifier circuit is fully differentially balanced or not (the next part of the chain is speakers, which will not care whether the amp was differentially balanced or not).

The VTL 450s (the old ones, at least) have a triode/tetrode switch on the back (do NOT switch while the amp is on - some speakers do not like it).
The Lamm's are not a truely balanced design because Vlad doesn't believe it is necessary for consumer requirement as he can achieve the low noise with his single ended design. If you read his manuals, or an interview with him he will state this.

Drive and hear your friends Lamm's, and bring your preamp to make sure it can work with their high impendence.. You might end up with not enough volume increments because of the amp sensitivity. (I went through 3 preamps before finding one that worked correclyt.. Rowland Synergy IIi and my Theta Gen VIII worked fine)
Man I hate writing long replies and having the computer crap out on me...

Condensed version: Grant and Bill, I don't know whether it was a 350A or 350A Reference. It was a couple of years ago, and I only had it on loan for a month or so. Definitely stereo version though.

Sutts: Another brand to consider is Plinius, either SA-250 mk IV, SA-102 or SA-103. All are very musical will killer bass, and are pure Class A bias designs.

I'm auditioning a Pass Labs XA-30.5 with Silverline Sonata III, driven by an Atma-Sphere MP-1 MK III. Alan Yun voices his speakers with Pass Labs, so I thought I ought to hear this combo.

I'm also using Speltz Zero boxes and doubling the Sonata III nominal impedance to 16 ohms. Very nice change...more spacious, open and relaxed, while still retaining the punch and drive. I'm not sure I'll ever use the Sonata III without the Zeros.

The bottom line is the XA-30.5 now is providing only 15 wpc into 8 ohms...but what excellent sound is resulting! I'm playing at easily 89-90db peaks with apparently room to go (but I haven't pushed it yet).

The Pass is a velvet hammer (which is exactly how I described the Moscode 401HR paired with Von Schweikert VR4 Gen III HSE). The Pass Labs/Silverline combo is the best I've heard in my living room since the Von Schweikert/Moscode combo, and yes I'd say the Pass/Silverline combo is better. Great bass...deep, tight and solid. Electric bass lines are clear in the mix and easy to follow. In fact, I can't recall following electric bass so easily in the past. Mids and highs are equally resolved, and the highs display outstanding clarity and extension with out sibilance. Mids have very nice weight, punch and drive.

No, it's not tubes...not quite as holographic or organic, but it's close, and it provides many things tubes don't (or at least haven't in any of my systems). The amp has only about 30 hours on it, and already it's making an impression. Supposedly, it won't come into full bloom until 100-150 hours.