HW Review #5 -Gary Koh’s No-Loading Genesis Phono Section
There are times in this hobby when we run into a match made in heaven. It does not happen often, and sometimes it is only because it is new and we are excited, but sometimes it is real and makes a huge difference in our perception of reproduced music.
The synergy between components is something we rarely talk about, we review a preamp and discuss it in our system but how does it really react with a bunch of amps and cables? Not much said. The marriage of the Genesis no-load phono stage and the Zu Denon 103 is one of those rare moments when you keep pulling out more and more vinyl you know so well but suddenly rediscover anew.
That does not mean the Proteus Diamond, the Lyra Atlas, or the Audio Technica Art-1000 are not good matches, they are, but when you find a combination that costs 1/5 th to 1/12 th the price and you do not miss the other cartridges, you have something magical.
I first began listening to the Gary Koh designed Genesis Phono stage using the Art-9 by Audio Technica: a very clean, very open combination that checked all the boxes for speed, openness, bass detail, and low noise but sounded a bit uninteresting. Popping in the Lyra Atlas of course opened everything up, increased my involvement and brought me information I had been missing. The Atlas is world class, the Genesis is world class, the combination was spectacular for $20K plus (a lot plus!!) as one would expect of products designed to do the best we can technically do. Funny thing happened, I put in the Zu Denon 103D and all that stayed the same but an organic quality attached itself to the midrange that put Dean Martin in the room, as Art Dudley always says about the Denon.
So, now we have a 60 year old design mated to a state of the art phono from this century producing music that I can honestly state is so involving, so delicious to listen to it might be fattening!!! The soundstage is wide, deep and full of orchestral sounds with none of the floating moving images we have come to expect. I was using a gimbal 12” Fat-Boy tonearm, no anti-skate, on a VPI direct drive table, so speed and noise were not issues. The amazing thing about the human voice is there is no halo around it, it should just appear in space as recorded, nothing to tell you there is a voice there other than the voice itself. From Dave Bailey explaining who was playing the instruments in his sextet, to Steve Lawrence telling how life was worthless “Till There Was You” or Ella explaining the joys of “Black Coffee,” I was mesmerized.
Let’s get some technical things out of the way: The Genesis Phonostage exemplifies the design philosophy of "simple as possible and yet no simpler" Gary started out by designing the most sophisticated cartridge loading system he could devise because the two phonostages he had at the time had sophisticated cartridge loading. But one day, he asked himself "WHY?" why load the cartridges? He dug into it as he always does. A bit of research later, he found out that cartridge loading was needed to tame the resonance caused by the tank circuit; which comprises the inductance of the cartridge, the capacitance of the tonearm cable, and the high input termination of the phonostage.
But the minuscule signal that the cartridge puts out would be damaged (or sucked away) by the loading resistor. And moreover, changing the "flavor" of the loading resistor would change the sound. So, what are we listening to? The sound of the cartridge or the sound of the loading resistor? That turned out to be why phonostages sound so very different and some audiophiles in Asia "roll" loading resistors like we roll tubes!!
So, as Gary does, he began with a clean slate and set out to design a phonostage that is as transparent to the music as possible. The RLC tank circuit resonance is unavoidable - it will always result in a resonant peak that may be 30dB to 50dB or more. But that resonant peak can be managed.
To do this, he used the RIAA de-emphasis curve. All phono stages have to amplify 20Hz 20dB more than 1kHz, and to amplify 20,000Hz 20dB less than 1kHz. Which means that it needs to amplify 100kHz at 60dB less than 1kHz - and the resonant peak lives in the frequency above 100kHz.
Gary’s design has a single wide bandwidth gain stage that amplifies 1kHz by 82dB. It has frequency-dependent gain following the RIAA de-emphasis curve and hence amplifies 20Hz by 102dB and 20kHz by 62dB. The RIAA de-emphasis curve is then allowed to extend to unity gain at 1.2MHz. Any resonant peak from the tank circuit is amplified by less than 40dB (60dB below 1kHz). No loading needed!!
The unit is fully solid state and is left on all the time. Even more exciting, it comes with Gary’s phono cable which uses no ground. Now that is something to write home about: Absolutely noiseless and no grounding to the turntable!! What this gibberish adds up to is a phono stage that outputs a smooth, detailed, and most importantly, coherent sound that you can listen to for hours with no headache, wine needed to enjoy, or artifacts from that resonance peak. The combination of Zu Denon 103D or Music-Kraft Denon 103D and the Genesis phono is so enjoyable, so easy to listen to, and so revealing I feel almost compelled to turn it on. Let me just state one other important item, the standard Denon sounds great, the 100 Anniversary model sounds even better so if you can’t locate the Zu or M-K a standard one will tickle your fancy.
It is a joy not to worry about loading, to have no adjustments, plug and play and enjoy your music, I know I am. BTW, for some reason the Genesis Phono works with the Grado Epoch and other stellar moving iron cartridges even though it would appear not to be a good match.
Final thoughts, Mat just procured a new Atlas for me and the new Lyra Atlas and Genesis combination is so good you will be looking for nothing else for years. The sound of the new Atlas broken in with 25 hours is so fast, clean, and easy to listen to I will modify my previous statement: If you have the money, this is a must have combination and I cannot imagine getting more information out of the grooves.
World class phono and fully recommended with no negatives I can find. What more can I say, I’m listening to the Moody Blues on the Genesis as I write this!!!!!!
The Genesis Phono Stage gets a solid 9 out of 10 stars!