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

Showing 6 responses by gsm18439

Charles and I have had similar experiences. SET amps are not created equal. IMHO there is more variation among them than among SS amps, for example. It is as if the simple circuit and low power of the SET design makes it more susceptable to the components chosen - starting with the power supply, the output transformers, and the rectification and including the tubes themselves. Along these same lines, it is as important to match the SET with the speaker. It is not just the power, but the execution of the design.
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.
Rebbi

I visit China three or four times each year - sometimes more. While I cannot attest to the wages and conditions of the workers used by the Commonsense manufacturer, the standard of living in China is no longer third world. I would not worry that you are contributing to oppression of the masses. Just the opposite.

As far as 300b tubes are concerned, however, you do have a point. Top of the line 300b tubes sound different and better and sweeter (and more linear) than stock tubes. But they are pricey.
Larryi

I came to the conclusion that my speaker cable runs (estimated at 30 feet) contributed to the thin sound of the 45 and 2a3 amps. Plus Phil (213Cobra) is adamant that the Def 4s need more than just a a couple of watts.
Charles

I have been visiting China for almost 15 years, and your comment is spot-on. Not everyone, of course; and there is the problem. But Beijing has gone from a city of bicycles to a city of American and German cars. My many students have a standard of living no different from their US counterparts.