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 4 responses by darkmoebius

Great starting point for your blog, Rebbi

Maybe a little primer on what you had before and what you thought was lacking and what you are searching for
Rebbi, I think it is worth revisiting one very important remark in this long(ish) thread:

"10-07-14: Charles1dad
Hi Seikosha,
The limiting factors are the quality of your transformers and the stiffness of the power supply section."

Why is this important? Because - I believe - that a lot of times when people talk about an amp "running out of power" it is more a function of the power supply's ability to store/deliver power to the output tube than the amp's stated wpc. This is especially true in SET amps.

That's why we find that one 8wpc 300B SET amp can drive a specific set of speakers louder without stress than others. The transformers also play a big part in why one amp may seem to "dig deeper" or have better bass than another amp rated at exactly the same wpc.

Let me recommend Art Audio amps - across the board, this company is famous for building SET amps that drive speakers far beyond what their ratings suggest. The company prides itself on building each with an incredibly robust power supply. I've personally owned their PX-25(6 wpc) and Jota (300B/ 20 wpc).. Look up the reviews of these amps, they are some of the best...and expensive. (though, there is a used PX-25 here on A'Gon for $2.5k - a steal)

The 6 wpc PX-25 is one of the finest SET amps I have ever heard. It is truly a "reference" level component. One pro reviewer summed it up best by say saying notes sound "as if they were lit from within". It played with delicacy and power. Richness and purity. And for giggles. I even ran my 89dB/4 ohm(not a good match for SET) Jean Marie Reynaud Twins mkII moniors with it fairly often. It really didn't have much trouble at low to moderate levels. Not a lot of bass, but the mids and highs were pretty damned good at low levels.

The Jota(KR 300BXLS or AV 320B SL tubes) and especially the high-current version at 24wpc (KR VV32B tubes) will likely do really well with your speakers. Check out the professional reviews of these amps, they kick ass.
Alamrg, I think this Positive Feedback review excerpt could help explain why Jazdoc's PX-25 "ran out of gas at mid-high listening levels" with his Daedalus Ulysses:
Although I know that Lou did not design this speaker specifically for low-powered tubes, the Ulysses can certainly deliver when driven by them. Is your passion the gorgeous sound of low power tubes? If so this speaker can accommodate you, though within limits. I felt at the 12-watt push-pull Audio Space amp was probably at the lower limit of power you could use and still get realistic dynamics. The 28-watt 845 Consonance SET performed very nicely.

How about mid- to high-power solid-state or tube designs? The Ulysses was built for high power. When I used 15 watts of class D power I loved the unlimited realistic dynamics that made the music seem so natural. My only regret was I didn't have a chance to try this speaker with some high-power tube amps.

Which type of amplification/source did I prefer with the Ulysses? Usually, whatever I was listening to at the time. Pressed for a decision on one, I have to give the nod to the Consonance Cyber 845, and my analog rig (VPI Scoutmaster, Shelter 501, and Aqvox Phono 2Ci, Gingko Cloud 9) which together gave me some of the most extraordinarily cohesive sound my room has ever been graced with. If you read Lou Hinkley's quote "coupling high efficiency with high power handling makes for effortless reproduction of music" it is obvious that he prefers a high-power amp for these speakers. I look at the Ulysses low-power affability as a big plus. This chameleon-like transducer is friendly to many different types of amps, and it truly lets you enjoy the characteristics of each and every amp. Rare indeed and a dream for audiophiles who enjoy the sound of more than one type of gain device.
I love it! The new backstory really helps to let readers know where you are coming from, the constraints you are working under(room size & WAF), and where you are hoping to go.

BTW, I also started out with some 2C's. A great buy for their time. SET, and SET-friendly speakers, are a whole different world from the Vandi approach.