Reader comment on Digital Amp Company amps

[mfsoa]

I don't think this'll violate any rules here. If so, lemme know.
A really nice reader comment on The Absolute Sound website:

With time, I came to suspect (fairly recently, I must confess) that the problem was that 60-100 watts per side tweeter amps were never powerful enough for the actually highly inefficient Tympanis' tweeters. But, where to find a powerful amp with the required hi frequency characteristic (dear to me) of a quality high end tube amp without the super-premium price, that I actually could try, at home, in my system? Not very easy these days. Fortunately, I stumbled into a couple of reviews of the products from the Digital Amplifier Company. The designer, Thomas O'Brien, does not modify B&O ice modules or anybody else's. He uses his own and holds several patents in digital circuits (all of this in his website). Prices are extremely reasonable for the kind of power and quality, and there is room for customization (including over 1000 watt monoblocks). More important, he offers a rather flexible 30 day full satisfaction guarantee. I selected two 4800A amps delivering over 640 watts rms for each of the two frequency segments, that is, over 1200 watts rms per speaker, in a vertical biamp configuration. I selected that particular model because a well respected industry player has expressed preference to use that model with his premium tube line stages--I use a Cary Audio all tube line stage.

This configuration, used with a full line level passive x-over (resistors and capacitors, no coils, 6 dB per octave), has completely eliminated the problems that I have been suffering for over 30 years. Now, I have no compression or shrillness, regardless of musical program. Just fully coherent and extended sound, with limitless, distortionless dynamic range and the same mid and high frequency smoothness of my favorite tube amp I was previously using. This in addition to the exceptionally extended and controlled bass that appears to be a trade mark of this brand of amps-- in this case being delivered through the Timpani ID's bass/mid panels, themselves still considered a benchmark for bass and low mid range reproduction, as Harry Pearson states it in this review (and in Part II, in the current issue of The Absolute Sound). All of this with a phenomenal sound stage of over 19 feet wide, close to 7 feet tall ( I have 12 foot ceiling), and depth reaching far beyond the wall behind the speakers. Plus all the audiophile attributes: musicality, resolution, detail, excellent transient attack and decay, pin-point imaging, three-dimensionality, palpability, etc. I had those elements before to a large extent, just even more of it now. Most impressive is the density of the sound field, to the point that it feels as if one is being transported to the performance itself and drawn into it...actually, it is like one is being immersed into the sound field and engulfed by the body of musical energy filling the performance's venue. I am sure most of this is related to the immense power response that these amps make possible for my system to deliver in my largish room, in combination with the sheer size and nature of the Timpani 1D's themselves (fully refurbished by Magneplanar 7-8 years ago, a significant improvement in itself due to improved materials and work techniques, after 30 years), but I have no doubt that all the observed benefits are a result of a synergy or, better said, the ability of these amps to deliver all the driving power with the quality that Magneplanar's very fine speakers evidently require.

dr.larkos

[JLM]

Interesting:

60 - 100 watt tweeter amps (not enough)??   

A big digital amp satisfying a tube guy 

Lots of clean power is always preferred (now I feel downright frumpy with my 100 watt digital monoblocks)   

[richidoo]

From what I could find online, Tympanis have ~79dB sensitivity and low impedance typical of planars.   Thanks for posting this Mike. I always enjoy reading D.A.C. reviews, they are always so positive!

[JLM]

Wow, those gotta be some kinda speakers to put up with 79 dB/w/m speakers.  No wonders he mentions super expensive tube amps, compression, and lack of dynamics.  I wish my 91 dB/w/m speakers were a bit more efficient.  (I know high efficiency can reveal system noises.)

[richidoo]

It's not an official rating, I couldn't find that anywhere. I calculated the sensitivity based on a classified ad I saw listing the sensitivity as 93dB @ 10 watts. Which sounds like typical audio manufacturer marketing spin, so it's probably from Magnepan. Convert watts to 2.83 volts because it's a low impedance planar, and then back out -3dB for each halving of power down to 1W.  Just a rough guesstimate.