2. speakers
  3. 1135803503

Myth: low-power high-efficiency

The past 6 - 8 months I have been living with very efficient speakers (~ 109dB/m/w) driven by low-power SET amps. The amps use 300B output tubes for about 7 wpc. On paper, this should be a match made in heaven. In fact, the combination is capable of wonderful nuance, subtley, harmonic richness, and tonality. It is really pleasing, especially on chamber and jazz music. Except for one thing - dynamic energy. I am not referring to loudness. It can deliver more undistorted volume than I care to listen to. I'm referring to immediacy, presence, power, and punch - the life of the music. If you go to the symphony, or live blues, than you know what I am talking about. Next week I'm taking delivery of a 90wpc PP amp, to audition in place of the SET. I need an amp that can maintain the purity of tone and harmonic texture of the SET, while delivering more power, to grab hold and take control the 15" bass driver in my horns.

I searched the archives, but have not found a similar post. Are there any other high-efficiency low-power people who moved to a higher power amp? Are you satisfied now?

Scott
skushino

Showing 2 responses by restock

restock
831 posts
 
As Boa2 (or better Terry Cain) so nicely mentioned: Keeping a second amp around for times when you need the additional dynamics seems to be the best idea. My Cain Abbys sound already incredible on 2 Watts for most music: Immediate, lively, engaging, with nice tonal and harmonic rightness. However, to get absolute dynamics and bass control I need a couple of Watts. Of course, this is not too surprising in my setup: I used an 80W amp on a set of 89dB speakers before which would translate into roughly 20W into the 94dB efficient Abbys.

Also, one more comment: Different tube amps can sound quite different and from descriptions the 300b is NOT the most immediate and punchy sounding tube (no personal experience with the 300b though). Did you try any of the other varieties of tubes, e.g. 2A3 or 45? While lower in power they might give you more what you are looking for.

Also, amp-speaker synergy seems way more important with higher efficiency speakers of the horn or single driver variety. E.g. I was quite under whelmed with a pair of Zu Druids on a Cary Rocket 88 or even on a Cary 300b amp as well. Then again, my Abbys sounded much less engaging with a Jolida EL34 based PP than with a 2 Watt Bottlehead amp. Go figure... :) . A First Watt F1 does wonders though in my setup in terms of dynamics and bottom end control.

With best wishes,

Rene
restock
831 posts
 
Aside from its enveloping, holographic nature, this tube in certain amps will drive quite well, and give you considerably deeper and punchier bass than will the 2A3, especially when the amp is SS rectified.

Howard (Boa2), sounds like I got to try a pair of Welborne 300b amps someday :). Of course this is just your fault: You could have sent me the Welborne pair you tried a couple of months ago ;). Actually, why don't you just sent all your equipment north of the border, I always wanted to listen to a pair of KHorns driven by Wrights or a Mac.

Anyway, fun aside, maybe sometime down the line I will be able to listen to some 300b amps. Actually, I already found some Audiophiles here; I just need to convince them to bring over their amp for some extended listening sessions...

Otherwise, I am curious to see how the "switch" to the Mac amp works out for Scott (Skushino).

Best wishes,

Rene
More to discover