What's the greatest bargain in SET these days?


Hi, Gang,
I response to my recent review of the Reference 3A De Capo BE speaker, someone wrote that if you really want to hear them sing, you should try them with a SET amp, or words to that effect.
That got me thinking. The De Capo's are 92 db efficient, which (correct me if I'm wrong) seems kind of borderline for low-power SET amps.
In any event, right now I'm running mine with a pair of Manley Mahi mono-blocks. They are switchable from triode (20 watts) to "ultra linear" (40 watts). I run them in triode all the time, and in my room, the volume knob almost never goes past 9 o'clock; more would just be too loud.
All that said, what do you guys think of running the De Capo's with a SET amp? And if I did, what's the best bargain in SET's these days?
Thanks!
rebbi
Hi Rebbi,
The more I reflect on your situation and choices, the more attractive the Commomsense Audio SET amp becomes.Mdemaio said it was very close to the Audion SET in sound quality. That's high praise given the Audion's stature and reputation. To get this for 1550.00 is remarkable IMO. This price gives you room for possible upgraded parts, I'd ask David if for a bit more money could the caps,wire,resistors be improved.These parts are crucial to getting top level sound. I wouldn't cut corners here to save a few dollars. He might say the chosen parts are already top quality(for all I know).

For instance using some Jupiter copper foil coupling capacitors would be excellent(they aren't crazy expensive either). Have him use the best wire you can afford, If you get this right the first time you'll have a SET that can keep you happy for many years. Of course I have no idea if he's open to this approach or not. SET circuits are so bare bones pure and simple that you'll hear what each part has to offer.
Charles,
I do agree that, relative to a pushpull amp, SET amps tend to have less bass extension and "softer" bass (less impact or punch). But, I really like the "tuneful" nature of SET bass. I hear more subtle variations and tonal qualities to drums and lower bass instruments with SET amps than with most pushpull amps. In that sense, pushpull amps tend to sound a bit "mechanical" and that punch has a "sameness" no matter the music; one does not get that sense with SET amps. From my experience, there is no perfect choice and tradeoffs are involved. I like the tuneful bass of SETs, but, I also like the extra kick I get from my pushpull amps. These days I listen mostly to my pushpull 349 amp.

Rebbi, I hate to complicate your search even more, but, you really MUST listen to a good OTL amp. Given a high enough impedance speaker, OTLs can be VERY good. Something like the 30 watt Atmasphere would appear to be a good match.
My Zu Def 4s have a built-in powered subwoofer so that any limits to bass extension inherent in an SET approach are eliminated. As I have noted previously, I evolved from a 45 to a 2a3 to a 300b SET. The 45 and 2a3 just sounded thin - perhaps, in part, because of very long speaker wire runs from one side of my living room down and through the basement to the other side. I also tried an EAR 859 that seemed too objective and did not allow the richness and tone of the Def 4s to shine. Ultimately, I settled on a 300b. (I also tried higher powered digital amps to see if I was missing any "oomph" and was pleasantly surprised by what a 300b SET could do.) As everyone has noted, the match between speaker with SET seems to be a bit more finicky than the match with other topologies. The issue becomes the management of the cost of experimentation. In my case I used Audiogon to purchase the first three or four amps that I tried before commissioning a new Ancient Audio custom-made 300b SET. I was able to buy and sell the progression of pre-owned amps without losing money - including shipping. It just took patience. Audiogon has become a tremendous resource in that regard.
Charles,
Last night, I was thinking that I should just get myself a Dynamo and be done with it and have a bunch of money left over for re-tubing. However, since the consensus here seems to be that the 300 B is something really special and that I should try to move in that direction to "get it right the first time" if possible, then it looks like I am looking at either the Audio Note Kit 1 or that Audio Nirvana piece from David.
The appealing thing about the Audio Note proposition is that I would know exactly what's in it, I would have the fun project of building it, and it is clearly heavily upgradable. Brian was nice enough to make me an offer with the better capacitors at dealer cost ($160) and the shipping fee waived. I also get three inputs and, I would imagine, better resale value, if needed, than pretty much any other kit because of the Audio Note reputation. Anyway, this would bring me in just a hair under my maximum budget. The only thing that gives me pause about this option is something I read in the assembly manual, which is online. It says something like, "The stock tubes are fine for testing and burning in, but a few months down the road you may want to get yourself some better tubes." The idea that I am going to have to sink more money into the amp so soon for it to show what it can really do is a little disconcerting! Thoughts?
As for the Audio Nirvana amp, it is very tempting because of the price and the possibility of discovering "The Greatest Bargain in SET Amps These Days." :-)
My hesitation would come from the untested nature of the beast, and from the fact that David seems to be, as far as I can tell, running this operation out of his home. (His wife picked up the phone the first time I called and I heard, "honey, you have a customer!") Of course, this is not unheard of in the Wacky World of Audio Manufacturing and distribution, but it does make you think. Of course, on the other hand, it's probably exactly is kind of small-scale operation that makes his pricing structure possible. He or, in this case, his engineer friend, design the products, have them manufactured in China, and then sell them here at a very low profit margin.
When I spoke with him yesterday, I asked him about the warranty situation. He said, in effect, that he hadn't had to think about it all that much because he had never had any returns on his first tube amp, which is a 6V6, Push-pull affair. I told him that I have a great, local repair shop here and I'm pretty sure he said that if it needed repairs, he would pay for them to be done locally.
I do have a certain hesitation around buying gear made in China. I really, really don't want this wonderful thread to be diverted into the topic of eastern versus western made audio gear. There are plenty of other rancorous threads for that purpose! I am not concerned about quality, because I know that there is some superb stuff coming out of China these days. I am more concerned about the ethics of relatively well off people in "first world" countries buying their luxury goods on the backs of workers in lower wage countries. But again, I'm not judging any of you who don't feel the same way or have the same qualms about this. But I'll call David today and ask about parts quality.
Rebbi,
Well you have put forth a clear summary of the tradeoffs that exist. David's SET is less money for the reasons you listed. I suspect you'd love the Dynamo but may maintain "what if" possibilities about the 300b difference. David's SET is not much more money and gets you a 300b amp. The Dynamo has the highly regarded Coincident name, quality and support. If the Commonsense SET is as good as it seems, it's a great opportunity. Somewhere down the road get top quality 300b tubes and you'll have something special.