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Harmonic Recovery System

as reviewed by Dave Clark, Victor Chavira, and Larry Cox





Apogee Caliper Signatures or Chario Hyper 2000.

Muse 150 monoblock amplifiers. Blue Circle BC3/BC3.5 preamplifier. E.A.R. 834P phono stage.

EAD 1000 transport and 1000 Series II DAC connected using Theta’s TLC (custom DC power supply) and Audient Technologies’ Tactic and Audit. Digital cable is a 1-meter length of Nordost Moonglo between the Tactic and Audit and a 6" length between the transport and TLC. Linn Axiss turntable, K9 cartridge and Basik Plus arm, Cardas Quadlink 5C tonearm cable.

Nordost SPM interconnects and bi-wired speaker cables.

API 116 Power Wedge and Coherent System’s Electraclear EAU-1.


one.jpg (6551 bytes)Blah, blah, blah digital. Blah, blah, blah analog. Now that that is out of the way, let me describe the Harmonic Recovery System processor from Source Technologies. The intent of the manufacturer is to restore harmonics to digital recordings, producing a more "analog" sound by offering an extremely high input (100k ohms) and low output (150 ohms) impedance, which creates a very friendly and effective buffer between a preamp (or CD player) and amp. My system is an ideal environment for the HRS, as it has a passive preamp. After all, the knock on passives is that they offer a difficult interface for a source and amplifier, and thus may reduce dynamics and curtail the frequency extremes.

Inserting the HRS between my Reference Line passive and Muse 150 amplifiers brought a substantial increase in dynamics and harmonic information. While I have recognized this as a definite shortcoming in my system, I was shocked by how much I was missing. Starts and stops came much faster, with a subtle but easily appreciated, and more "natural," decay of notes. There was a greater sense of a musical wave form dissipating into a blacker, deeper, and more dimensional background. Micro- and macro-dynamic shifts were equally transformed. The quiet became quieter, with greater clarity and finesse, and the loud swung with considerable force. Images literally jumped out, especially the percussion on Muslimgauze's Narcotic. Featuring well recorded drums and bells from the middle east, these were hurtled out and around in an enveloping soundfield with much greater force and tactile "living" dimensionality than sans HRS.

More like analog? Well yes, but still digital. Which may be taken as a compliment. If I may make an analogy, the HRS was like a turbo charger, revving my system to higher horsepower and torque. I found myself listening at levels a click or two higher than before, with less strain or fatigue. The frequency extremes were also transformed, with greater quantity and quality. Especially noticeable was the increase in bass slam and texture, which at times was a bit too much for me to deal with. I mean that in a very complimenatry way. Plucked or strummed bass strings were again very tactile with a "feel me, see me" presentation that was quite captivating. Dub tracks from the killer CD Dub Meltdown by Bill Laswell and Style Scott were delivered with amazing slam and presence in a way that really got me up and dancing. Excellent pace and rhythm to get the room a shak'in.

This may be attributed to the increase in listening volume, but the presentation really opened up! Though depth seemed largely unaffected, the soundstage became wider and higher. Images were placed a foot or two farther to the left and right and somewhat further out into the room, with a more up-front perspective that heightened the listening experience. While I was hoping for greater palpability, well, the HRS has no tubes in it. It's not that I couldn't sense greater harmonic information—obviously, from what I have described, I did—it's just that images never really grew 3D-like. Greater air and textural detail, yes, definitely, but no advancement in creating the illusion of "living dimensional images" in the room. We've gotten closer to this illusion with tube various preamplifiers and amplifiers in our system. If only John Sollecito could do this with the HRS, we'd have it all!

I didn't hear any other shortcomings, which is not to suggest there may not be any. It's just that I didn't hear any perceptible added grain, grit, veils, or whatever. No strange tonal shifts or timbral anomalies to cause one to scream and wince. Sorry, it was just too much fun to have in the chain. The unit is fast and transparent and appears to produce the effects claimed by the designer. Of course, you will need an additional pair of interconnects, and I have yet to try a specialized AC cord, as is suggested in the literature which may even further the unit's performance.

The HRS is not the be-all-end-all for the shortcomings of digital, nor does it totally mitigate the inadequacies of my EAD 1000 DAC. And no, I didn't find the HRS to make my CD's sound closer to my analog source (when I say analog I am referring to an LP and not a master tape). As one can tell from my opening, I take the position that analog is analog and digital is digital; the two are simply separate, and should never to be confused with each other, approaches to musical reproduction in the home. While both have their pros and cons, I am more interested in getting each to sound more like what I perceive to be an enjoyable musical experience. How you want to define that; a live instrument or event, the faith-full or accurate reproduction of what's on the master or simply the disc (oh yeah let's talk about the whole recording process-now there's an area ripe for improvement)-I don't care. But I do think it is a mistake spend any effort in getting digital to sound like an LP, heck just make it sound like music. And the HRS does just that for a very reasonable price.

I would still love to get more of a tube "presence" out of our system, but it appears I’ll have to wait for some other product down the road. It boils down to two questions: "Did I enjoy having the HRS in my system?" and "Would I buy thiscomponent to use on a permanent basis?" Yes I did, and yes, I plan to do so. The HRS really did its thing in my system. Considering what it accomplishes for the price of admission, show me the way in!
Dave Clark





Spendor SP 7/1.

Audible Illusions Modulus 2D preamplifier. Classe CA100 amplifier.

CAL Icon MkII CD player.
Oracle Delphi MkII turntable, AudioQuest PT7 tone arm, AudioQuest 404i cartridge.

AudioQuest Emerald 3x interconnect and Midnight 3x speaker cables.

API Power Pack.


two.jpg (6646 bytes)I was not enthusiastic about sticking the Harmonic Recovery System box, or any other box, in my system. Even the name put me off from the get-go. I have tubes, and harmonics like the solid state and passive gangs wish they had. Also, my ATC SCM 20 speakers need a lot of power, and I believed that this was the most desirable upgrade for my system. My amplifier dissatisfaction had grown to the point that I took home a CODA 10.5 to see if that would drive my ATC's better than my Classe. It did, but at twice the price. The bottom end was richer and fuller, and provided a sensation of air striking my chest during low bass passages, all good things. After having the Coda in my system, I was ready to start saving for a bigger amplifier.

My initial lack of enthusiasm for the HRS was confirmed by placing it between my amp and preamp. Images scattered from between the speakers and clung to them like frightened children. Timbre was reasonably good, but the imaging thing was so off-putting that I figured I could just hammer the product and move on to review something else. I thought that I’d not only saved the dough for the HRS, but didn't have to buy yet another set of interconnects. Phew! Then I changed things. I put the HRS between my CAL Icon MkII and my E.A.R. 802 preamp, and my immediate response was that I was doubly saved! Not only is $400 is a pretty reasonable price for the Harmonic Recovery System, but it made such an improvement that I feel I can put off buying a bigger amplifier, at least for a while.

The HRS is a find. No, it doesn't increase the resolving power of my Classe, but it does increase the oomph factor at low volume levels. One thing about my system is that without relatively high volume levels, my amplification only hints at what the bottom end of the ATCs are capable of. After inserting the HRS, I suddenly have bottom end at low volume levels.

This is really nice, because I get a greater sensation of a full range system without having to send the sound pressure levels way up. I like playing music loud, I just don't want to have to do it all the time. Stand-up bass on Missouri Sky by Pat Metheny and Charlie Haden is richer, more woody sounding, more complex than just thump thump thump. I think that increasing the complexity of sound/music being reproduced by the HRS is at the root of all that makes it a wonderful contribution to my system.

Bottom end is only a part of the story. Vocals become a lot more rich and resonant. The second album by The Story is wonderful, especially "Fatso," a beautiful sounding and funny spoof of dieting. Vocals on this song (and other female vocals) are presented more warmly, while retaining their bell-like clarity, much as human voices are in real life. There are many other small cues which make this "box" a welcome addition to my system. Yes, it does require another set of interconnects, but they can be short. I have made no effort to find out why the HRS works. It just does. Check this pup out. Do as I did, however, and make sure you stick it into different places in your system. It makes a substantial difference, and a welcome one.
Larry Cox





Magneplanar .5.

Sonic Frontiers Anthem 1 amplifier.

Audio Electronics CD1 player.

Kimber PBJ interconnects and Tara Labs RSC Prime Bi-wire speaker cable.


three.jpg (8484 bytes)My audiophile friends know that I have a huge aversion for little black boxes that claim to improve sound. It all goes back to my teenage years, when I was so heavy handed with the graphic equalizer. Now I try to have as little as possible between me and the music. In my opinion, money is better saved for a better component than squandering on a tweaky black box. That was my opinion, at least, until I heard with my own ears the audio miracle of the Harmonic Recovery System (HRS).

The small HRS unit was placed on top of my Audio Electronics CD1, now gloriously re-tubed with vintage Mullard 12AU7s care of Kevin Deal at Upscale Audio. I always listen to a component casually before I listen critically, but this was not possible with the HRS in the system. The first thing I noticed was how potent my system sounded. The HRS increases the signal by 3db. However, even at its maximum setting, my system doesn’t play as loudly as a medium setting with the HRS. Dynamics were only part of the story, though. The musical presentation was absolutely crystalline. I was happily listening to Charlie Haden and Pat Metheny’s Missouri Sky when track seven, "The Precious Jewel," started up. I couldn’t believe what I was hearing.

I have listened to this track often, and always assumed the intro was played on a twelve-string guitar, or two guitars playing the same thing at the same time. Now, however, I learned that the guitars are not strumming in syncopation, but playing against each other. The guitar on the right accentuates a down stroke, followed by the guitar on the left accentuating an upstroke, and so forth. This musical moment passes quickly, yet it was reproduced so realistically that I was astounded.

Musical details are like small treasures that producers bury within their recordings, a chime here, a rainstick there, a soft click on a clave. Michael Franks’ Abandoned Garden is one such multi-track studio recording. HRS captures these treats and brings them into sharp relief, enhancing the musical tapestry. HRS changed my understanding of this heartfelt homage to Antonio Carlos Jobim. Where once I envisioned a vocalist and rhythm section, I now grasped the complexity of this excellent recording. Naturally-miked recordings such as Orchestra Nova’s Salón New York also reaped rewards when passed through HRS. Strings played pizzacato can often sound like one fat pluck. HRS rendered all the individual plucked strings. Sustained notes resounded like the sum of their elements—first and second violins, violas and cellos—rather than a compound tonal color.

Listening to works for solo piano through HRS was like experiencing them for the first time. Antonin Kubalek’s My Gift to You is a collection of favorite piano encores. On "Clair de Lune," my system was never capable of giving the impression of the lowest pedal notes. With HRS, the notes are rendered with a vibrancy worthy of a grand piano. HRS will also had me reassessing my understanding of what constitutes a good soundstage. I thought that some things in a recording were meant to be shadowy and in the corners. With HRS, though, the corners are not where I thought they were, but much farther back. The difference was cinemascopic. Important events weren’t limited to the center of my focus. As in a great film, details and plot clues unfolded all across the screen.

The HRS was most impressive indeed. Believing that every product has an Achilles heel, I tried for several days to make the HRS sound annoying or aggressive. The fact that it doesn’t corrupt the music is remarkable given the delicate parameters of soundstage and subtleties of sound with which HRS works its magic. Disc after disc, small wonders were continuously revealed to me. With my system sounding better than ever, I became suspicious. Surely, this sonic miracle must the result of some sort of electronic trickery. I had to understand the inner workings of HRS, so I called Source Components Electronic in Connecticut. I spoke with Mr. John Salecideo, who explained the HRS process.

The unit is an interface optimizer between source and amplifier. The device dramatically lowers the signal-to-noise ratio and provides a "friendly" output impedance for the amp. In effect, my Anthem Amp1 thinks it is "seeing" a megabuck preamp rather than the variable output of my CD player. The HRS is built to a standard many times its retail price. First-class parts are used throughout. The process is purely analogue, and not the result of equalization or smoke and mirrors. For a more comprehensive explanation, call SCE or hit their website listed at the end of this article.

To conclude, I offer the following advice: If your system sounds good to you, I urge you to audition the Harmonic Recovery System. You will be shocked at how much you’ve been missing. If you’re at the point of upgrading a weak link, by all means do so. Then go out and beg, borrow, or buy an HRS. Just don’t ask for this one, because it’s mine. 
Victor Chavira

HRS Harmonic Recovery System
Retail $450

860 - 528 - 2892