SET sound without a lot of money


Any experience or opinions on the Almarros, Music Ref RM10 mkii, or the Joule Electra Stargate amplifires? Looking for a good SET experience without overly-colored sound or congestion, while pushing enough current to excercise existing 91db speakers at low to moderate volume. I would like to swap one of these occassionally into my system without having to rebuild (re-buy)a whole new system to accomodate a tradional low-watt 2A3, 45, or 300b amp.
erfranke
Ignore this advice at your own financial peril: Have Jim Nicholls from JWN amps build you a custom tube amp. You'll be absolutely amazed by what you'll hear. I recently listened to a set up which consisted of a $8000.00 pair of horns being driven by a 10,000.00 SET with a very pricey turntable and culdn't help but smile thinking my rig consisting of my JWN amp, and Shelby+Kroll Nano monitors gave up very little to that set up in terms of clarity, resolution,soundstaging etc...
IMO Vienna Acoustic speakers are not tube friendly at all. If you can borrow a tube amp you will hear what I mean. The tonal balance will be off because of the impedance swing of the speakers. If you can get one with a free trial then it might be worth a shot.
95db. I listen to rock, folk, jazz, Sinatra-era vocalists, c&w (wife's choice). Room is 17 x 35, vaulted ceilings. Listening to Van 'Too late to stop now'. Earlier, MC5, Seger,
I was driving my Sophia Baby into 92db speakers. Sounded pretty good at moderate volume. Then I traded for Cain & Cain Abby's. Wow. The music...even at higher volumes...wow. You gotta find the match, it's out there.
Audio Mirror offers two beautiful sounding and looking SETs, 20 watts per channel and 45 watts per channel (I have this one for my 87db 6 ohm (min) speakers). Not 300B or 2A3, but 6C33C - powerful and beautiful sound nonetheless. If you are near Atlanta, GA, you may come by for a listen.
If you are looking for Great sound without spending over a lot of money($10K), then you should look into Sophia Electric 91-01 mono-block 300b single ended amplifiers.

There is a Positive Feedback review detailed on 91-01.

WA
Larryi,
You wrote words of wisdom, nothing beats critical listening for building a component to its highest level. Random parts selection(based solely on reputation) is a bad recipe.
Erfranke,

Thank you for bringing the Tube Audio Lab site to my attention. It appears that the various designs are based heavily on old topologies and clones of specific designs, like the Western Electric amps.

My only concern would be, the extent to which the designer/builder actually listens critically and has made design and parts choices based on such auditions. There appears to be a lot of mix and match alternatives when it comes to the specific parts. I know that part choice is EXTREMELY important, and there is no such thing as a "best" or "better" part--it depends on application and personal taste.

I've heard amps where the "upgrade" consisted of replacement of cheap capacitors and resistors with much more expensive, and supposedly better, parts, such as Blackgate capacitors and Vishay resistors. The result of using price/popularity as the guide, instead of auditioning the results, were horrible; the designer chose those "cheap" parts for a reason.

If you go this route, it would pay to have a long discussion with the designer/builder about what he actually knows about specific choices. He does offer a terrific range of parts (when used correctly), and there is potential to make fantastic gear with the likes of Hashimoto or Audionote transformers, etc. But, there is also the potential to make extremely expensive disappointment too.
I bought a "kit" from Min at Tube Audio Lab. Great guy, good to do business with. He does great work on the amps he builds as well.
Anyone had experience with "Tube Audio Lab" advertised here on the Gon? Appears he builds a variety of different amplifiers and sells them directly.
Erfranke,
One reason you may not have gotten the "hype" about 300b SET amps is they`re so many of them around. Probably 40-50 commercially available,at all different levels of price,quality and sound.

Due to their very simple circuits and fewer parts count,when constructed to a high quality standard they can sound so pure and transparent.If not then colorations become quite evident.

As Larryi said, the level of transformers,parts and power supply will make or break these amplifiers. IMO when implemented right they present realism better than anything else I`ve heard so far. Its just that the better ones are`nt cheap.
Regards,
Larryi,

Thank you for your post, you nailed it. Your assessment could not have been stated better. I have experienced the 211/845 powered 300b and could not quite understand what all the hype was about the "300b". I suspect remaining true to the purer faith of low watt 300b/2A3 amps coupled with fewer driver, more efficient speakers is the way to get the best of them. For now, OTLs are astounding and they are my primary listening vehicles (MP3 and S30 AtmaSpheres). But the damnable curiosity never ends!
Erfranke,

As I understand your request, you are not looking for a replacement amp, but, something that can be used once in a while to mix things up. What would be helpful is an idea of what you are currently going to keep as the primary amp.

There is a WIDE range of sonic offerings when it comes to SET amps. For my taste, the BEST of SET sound comes from those low powered directly heated tubes (e.g., 34, 2a3 and 300b), and less so for the higher power offerings. Some listeners also prefer single tube SETs to those with parallel output tubes (I own, and like, a parallel 2a3 SET amp). These kinds of amps limit, to some degree, the kinds of speakers that can be matched to the amp. I have heard very nice sound from low-powered SETs used with some not very efficient speakers so it is possible for you to use such amps in a small room as long as volume level is kept reasonable. The most difficult kind of music to get to satisfying levels with these amps will be large-scale symphonic music and large-scale choral works.

Some of the higher powered SET amps that use tubes like the 211 and 845 are more versatile, though I don't think they quite deliver the same kind of immersed-in-sound experience of the smaller SET tubes. These amps must have a robust build because of the high voltages involved and so I would actually be a bit leery of "cheap" amps. Even with low-powered SETs, cheap probably means compromises on the output transformer which is hard to do right with SET amps.

When it comes to speakers and setups that demand more power than a directly heated low-power SET can provide, I would suggest looking into OTL amps. These deliver the kind of immediacy, and "jump" that few other kinds of amps will deliver. Joule and Atmasphere make really nice OTL amps.
Boy can I relate!! I went through Various Triode, Pentode and Push Pull tube amps.....etc. Vandersteen, Legacy, Klipsch, a few monitors with subs.....etc. I'm in a very similar size room with very similar taste in music. I was always missing something in my listening sessions. I've even heard a $250,000.00 system that still wasn't what I was looking for. The system was great on presence, imaging and staging but was very fatiguing and straining to listen to. Take a look at my system. It's in the building stages but is still very rewarding to listen to. After I heard a good SET amp on some efficient speakers ( I'm talking 97db or greater )I've never looked back. This is just one persons opinion and it's not for everyone but I at least recommend giving it a try. I feel you will really need more efficient speakers though before you switch over to an SET amp. The amp won't be allowed to shine to it's potential. FYI...I just added a Cary AE-3 pre amp tonight and OH MY.....just what I needed to drive my 45SET amp. Good gain and soundstage with no coloration over my passive volume control that I've been using.
Listening area is small, 10'x10' and sitting distance from the speakers is close; direct energy listening without acoustic wall treatments. The set up is intimate to say the least but good for listening at low to moderate levels where detail can really come through. Jazz, vocals, acoustic, some orchestrated pieces, contemporary pop is the music genre.

Even sitting close, sound stage, air, holographic imaging of the OTLs are amazing. Still, curiosity over other circuit/tube designs have got the better of me, anyone else out there relate?
The Sophia Electric Baby is NOT a SET amplifer. It is a Class-A push-pull design.

Sophia Eletric's webpage for the Baby clear specifies that *S.E.T. Music Baby Amplifier stands for *Sophia Electric Technology. Not Singled Ended Triode.

The tube used in the Baby is a 6P1T. That's a pentode, not a triode. I don't mean to piss on your parade, but if you think the Baby is giving you SET sound, you're just fooling yourself.
ERFRANKE,

What are your goals and expectations on volume? Large room or small? I'm new here but have a fair amount of listening done on various SET amps with different speaker combo's. I'm not as full of technical specs as some but can maybe give you a nugget of info that may help. WARNING.....listening to a good SET amp can be very addicting and have you starting over from ground zero.....LOL
Ekwisnek,
I agree with you, if these speakers have that impedance characteristic(dips down to 1 ohm load!) this is`nt a good match at all(and I love a good SET amp).This will only result in much disappointment.
This is all very good information. I may have to lower my expectations absent a complete system revamp which would be more accommodating to the low-watt amps. My goal was to hitch something up to an existing SLP-05 which is packed away in a closet, for a little variety every now and then. Guess I have more head scratching to do.
I am a Vienna owner and I'm not convinced you could drive the Beethoven's with such low wattage and more importantly low current. The advertised efficiency is a bit of a fib as they don't show you the impedence curve. In the bass region the impedence can drop to as low as one ohm. Without global feedback or a higher damping factor you may experience a lot of bass warble even if you got them to play at acceptable listening levels. I know it doesn't really help answer the question, but wanted to offer that warning.
BTW,the 10 watts a side of my Sophia Baby is quite adequate
to power my Rega RS3's in a 12x11 room,as is the 8 watts of my Eastern Electric MiniMax for that matter.
Rega rates them at 89db (6 ohm spkr.).
I heard Almarro mono's driving Marten Miles 3 in a small room, very musical and easy to listen too in a small room. Pre's were VTL and front end CEC transport into AMR dac. Well worth investigating the brand from my limted experience.
Listen to an Almarro 318B or an Audion Sterling Integrated. Both put out about 18 w.p.c., sound excellent, and are well under $2,000 on the used market. Match them with moderately efficient speakers, sit back, and let the music flow!
If you're talking about the Almarro A205A, like the RM-10 it's not an SET amp. It's actually a single ended pentode:

http://www.6moons.com/audioreviews/almarro4/mk2.html

Sounds great, though; I owned one for a couple of years.

The Almarro 318 is indeed an SET.

David
Let's cut the shit. There is no good SET sound for not a lot of money.

Maybe, but I for one do not agree to your statement.

If you cannot build one, what you said is probably true but if you can, and understand what you are doing, then you can have a true SET that is most likely better sounding than what is commercially available and with better components to booth and lesser in price overall. Most if not all of the popular true SET amp manufacturer, Shindo or AudioNote for example, started via DIY.

I mentioned "true" SET because to me, a real SET sound comes from DHT output tubes! IMO, no IDHT SET, like Pentode strapped etc. has the real SET sound. In other words, them are just "wanna be SET's" he,he :)
The speakers are Vienna Acoustic Bethoven Concert Grands. one silk-dome tweeter, one mid-range, and 3 six-inch bass drivers per speaker
I'm really impressed with my Sophia Baby Electric which I picked up for around $400.
I have owned the RM-9 and RM-10, but a different points in time. I wouldn't say the RM-10 is a considerable upgrade over the RM-9. They are both outstanding amplifiers. I will say if you don't require the 100 watt output the RM-9 the RM-10 will not disappoint you.

Personally, for SET amps, those suggesting the Almarro might be on to something. It's an amp I've considered before.

What kind of speaker do you have. Speakers vary so much, they may say they are 91db efficient but then they take a ton of power to drive.
http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1323645303&openmine&zzZmanastronomy&4&5#Zmanastronomy
The Music Reference RM-10 is not a SET amp. It is an EL-84 based push/pull.

It is however an amp that is a game changer as a couple of us on here who also own Atma-Sphere amps can attest to.