Coda Technologies CS Amplifier Review

Unusual Application #1: Actively Crossed Speakers

I think it is a very good thing that I used amps which were voiced with the Legacy Audio Whisper DSW when operating it in active crossover mode. The entire structure of the soundstage, transient response, timbre of instruments, etc. shifts when moving from a traditional speaker to one which is actively crossed. I recommend those interested in the influence of active crossovers on speakers to read my review of the Legacy Audio Whisper DSW.

In such powerfully revealing rigs (I used two front ends during the time of review: the Ayon Audio CD-5, and later the Denon 2900 Universal Player as transport to the Eastern Electric Minimax DAC) the shortcomings of solid-state are quickly revealed. I had used three other amplification schemes with the Whisper DSW in hybrid active crossover mode (active bass and passive Mid/Treble), pairs of the Moscode 402Au, Pathos Classic One MkIII in Mono, and the Cambridge Audio Azur 840W. Oh yes, and one more – the golden toned VAC Phi 200.

The only amp I could move to fully active crossover mode was the Coda CS.

Though it is commonly thought that a speaker with midrange and above operating in passive crossover mode is superior to one with an active crossover, I found the results to be the opposite. It did not matter which amp was pitted against the CS in fully active crossover mode, the CS was superior in definition, timbral accuracy, soundstaging, coherence and macrodynamics. In the VAC Phi 200 review, I wrote that those amps came closest to the Coda CS used in an actively crossed system, but could not surpass it. However, the Phi 200 asserted itself as dominant in an apple-to-apple fully passively crossed setup.

Again, I believe the voicing of the CS and the Whisper were enhancing each other’s performance. As the stakes grew higher, the amp and speakers were complementing each other – synergy – such that the CS provided what the Whisper needed to excel. In a similar fashion, I found the Phi 200, which was used in voicing the King Sound King ESL, to have the same synergistic quality. You guessed it, the King was used in voicing the Phi 200.

During this time of the review period I had been culling discs from my collection to use as demo material at the C.E.S./T.H.E. Shows in January of this year. I ended up taking, among others, Delerium’s Voice, The Premier Collection: The Best of Andrew Lloyd Webber, and the soundtrack of Pirates of the Caribbean: Curse of the Black Pearl, by composer Klaus Badelt.

From the Delerium disc I played “Silence” featuring Sarah McLachlan and “Orbit of Me” featuring Leigh Nash. I contrasted the very well recorded and quiet “Pie Jesu” duet of Sarah Brightman and the young Paul Miles Kingston with the more difficult recording and volatile symphonic score of Pirates, especially “Barbossa Is Hungry”. This trio of tunes can put any rig through the gauntlet in a hurry. That is why I also used them regularly in setting up various permutations of the Coda/Legacy system.

I’ll share how I assess the qualitative changes to rigs based on these pieces of music. Starting with Sarah McLachlan, in less refined rigs her voice sounds “splayed,” due to the reverberations of the recording venue, while the electric bass seems somewhat indistinct. As the system becomes more refined one hears quite clearly Sarah’s voice in a very tight center image with clean distinction between her voice and its echoes. The bass, when it enters, is taut and not tremendously strong; the better the recording the less the bass will overwhelm and the more it will fit in snugly with the rest of the music.

“Barbossa Is Hungry” is a very tough piece to render cleanly, and there is so much action that most systems simply cannot capture all the nuances. Especially as the climax of the piece builds there is so much low-end energy that all but the most extreme speakers simply overload and the bass fumbles with distortion. I listen to the quality of the ghost-like lute (flute?) which appears in the right channel, as well as the acoustic bass’s razor-like edge as a strong tempo is established, also heard in the right channel. I listen to whether the chorus seems wedged into the piece or fits naturally, and takes up appropriate size in the background.

On “Pie Jesu” one hears a high degree of stereo separation between Left and Right channels. As the system quality grows and more subtle spatial clues are heard in the right channel, Brightman’s voice in the opening minute of the piece moves closer to center image. By the time Kingston begins singing her voice is centered completely. One clearly hears that she seems to be singing off to her right until he enters the duet. Kingston’s voice is flat, with little resonance, in all but the most refined systems. When you can hear his nasal cavity involved as well as his throat you’re getting more extreme definition from the rig. This is to say nothing about tonality or timbre, and there’s every bit as much to pay attention to in that respect as any.

The Coda CS was refined enough to elicit all the proper nuances of these pieces. It did not perceptually hold back the music through seeming rough or lacking in increasing detail. On the contrary, not only did it comply with increasing demand for detail, but did so while improving the tonality of instruments from the piano to tambourine. I was able to bring this amp the closest to the richness of a high power tube amp like the VAC Phi 200 of any solid-state designs I’ve used. That’s a very high compliment, as most SS amps don’t come close. There is usually a point at which the solid-state design craps out in terms of clarity or tonality, but the CS never did. I put it to extended testing with a radically good Redbook front end and the CS grew more attractive with every increase in front end finesse.

Unusual Application #2: DAC Opamp Rolling

The other unusual application used in this review system is a unique DAC with a higher than usual degree of configurability. It figured prominently in pushing the CS to extreme performance levels. I have written previously in my Audio Blast of this product; the Eastern Electric Minimax DAC. It’s cheap, at $750, and has the superb ESS Technology Saber 32 Bit Reference DAC chips. I thought that was a big story, and I trumpeted the performance of the Minimax. That was before I began Opamp rolling. I wrote a few articles about that endeavor, as it has been one of the most satisfying explorations in my reviewing career. Suffice to say here that if you have considered the Minimax DAC you will want to pay careful attention to that upcoming article. As they say, “You ain’t heard nothin’ yet!” I have rolled, and rolled, and rolled Opamps and in the process opened up veritable new worlds of performance. Many times reviewers speak of amps not holding systems back. My experience with the CS in this exploration of Opamps has been less of a matter of perceiving how much might be held back and far more a sense of what’s being pushed through – a strong sense of “all of it” getting pushed through. Like the analogy of a tube of toothpaste, some people are content to squeeze out most of it, then toss the tube. I get it all, to the point that as the tube nears the “empty” state I lay it flat on the bathroom counter and use the handle of the toothbrush to flatten the tube and force the contents toward the tube’s orifice. When I’m done with it, there’s precious little not gotten! In the same way I sense the CS is wringing the last bit of energy, vitality if you will, out of it and forcing it out the speaker’s “orifices.” More than with any other SS amp I’ve worked, with my ears tell me the entire signal is getting through.

I know that sounds absurd, but when you’ve heard enough solid-state amps you will know what I mean. Some simply sound as though they “retain” a perceived amount of the signal, as though there is an exchange taking place inside, grunt for precision. I do not detect that either is being sacrificed in order to supplement the other.