This is NOT a formal review....because I know I suck at it
Consider this to be my commentary, observation, opinion, desire to share information, and story of a personal eargasm based on two matched cMoy amps built by John Seaber in a balanced configuration. Before I publish this...I had to think carefully because I did not want to become a possible laughing stock here at Head-Fi or just keep it silent and enjoy my music. When a person finds a rare elation that many other can also potentially enjoy...one just can't keep it quiet.
First of all, John Seaber (aka blackinches) is a top notch person with great product and one of the best service I have experienced here. The combination of great product and service (and responsiveness) goes a long way of earning my business. That's why he is building my next budget balanced rig: the balanced mini^3
Back to the amp....and my unorthodox configuration...
SETUP:
When I first read this thread by Iron_Dreamer (
http://www.head-fi.org/forums/showpo...&postcount=10), that motivated and inspired me to test an idea of going balanced with my Senn HD650 and HD580 cans using my CIAudio's VDA2 DAC with VAC power supply.
I ordered two matching cMoys from John without volume pod and with gain switch. He carefully matched the two cMoys with matching resistors so the cMoys sound identical as possible. Since my intent was to use this purely as desktop amp, I took the battery out and used an expensive 24vDC output ELPAC power supply.
I connected a standard RCA to stereo mini cable from VDA2's right 0 and 180 phases and plug the mini stereo input plug to cMoy #1 (right side of headphone) and I repeated for the left 0 and 180 phase RCA from VDA2 to mini stereo input plug to cMoy #2 (left side of headphone). On the mini stereo plugs, the 0 phase was the tip of stereo plugs, 180 phase was the ring of stereo plugs, and ground was ground.
I modded the RnB's Grace 52 Senn cable from single ended to balanced TRS format to match the above stereo plugs signal orientation, where the - (minus) pole is tip of the TRS plug and the + (plus) pole is ring of TRS plug, per right and left side. Therefore the tip of TRS = 0 phase and ring of TRS = 180 phase per right and left headphone.
I plugged everything...double checked...triple checked...the connections. I turned off the bass boost on the cMoys. Set the amps to low gain. I lowered the volume on iTunes to lowest. I pressed to play Diana Krall's song, "Narrow Daylight".... I heard a loud POP and my drivers went dead.....JOKING;D
INITIAL SOUND:
When I gradually raised the volume on iTunes and heard Diana's song, "Narrow Daylight" for the first time on this setup, I thought the sound sucked. It was course, grainy, boomy, no soundstage, compressed sounding, piercing treble all over the spectrum,....I simply hated the sound. It wasn't even a decent music to me. I thought I wasted <$100 on amps, >$60 on ELPAC power source, and cut up a valuable RnB's Senn cable for nothing. I let it continue to play for few hours and heard little more on Diana's "`S Wonderful" and it sounded pretty good. The boomy bass tighten up and grainy sound was greatly gone. The soundstage returned little bit and compressed sounding was gone...and there were lots of details and channel separation. The first thing I noticed was the Senn650's dark veil sound was almost gone on the balanced configuration and it's the most powerful sound I have ever heard. The sound had potential so I let it sit and play music for almost 2 days straight without listening to it because I was too busy with work...and I had to tolerate my kids telling me I left the music on many times a day
BACKGROUND:
In this forum we read many people exclaiming, "OMG!!!", "eargasm" , "The best ever...", etc. when they are elated with quality of sound they never heard before. I rarely felt that way before with any of my amps from the past. I had many amps in the past. To list them, it goes something like this:
Stainless Steel "Toaster" MPX3 6SN7 with SLAM Adapters
Berning MicroZOLT (Sylvania Gold Brand 6201 & Russian 1960s 6SN7 tubes)
Updated Xin Supermacro 3V6 to near IV (AD797 with Buffers Bypassed)
Insanely modded X-CAN V2 (#1)
Xin Supermacro LE (ST-WA)
2005 MicroStack with Desktop Module (again)
Ray Samuels XP-7 (AD797)
MisterX XP Amp
Xin Supermicro IV
Rockhopper Audio's maxed out M^3 (Great amp!)
Upgraded (silver wire / blackgate caps) Gilmore V2-SE
Woo3 with enough NOS tubes to last until the next Ice Age
Mapletree Ear Purist + HD
Pinky modded X-CAN V2 (#2)
X-CAN V3 (few days...modded X-CAN V2 was better)
2000 Ok HP 100A hybrid Chinese amp
Headamp AE-1
Headamp Gilmore Lite V2 (twice)
Ray Samuels SR-71
Xin Supermini 3V3
Modwright CIAudio's VHP-1/VAC-1
Corda Aria
2005 Headroom MicroStack with desktop module
Zhaolu D2 with discrete head amp
Shellbrook Super Mini Moy
They all have one thing in common. They are all single ended. Out of them, the best sounding amps were my last two amps; microZOTL and Toaster MPX3. They made me think I would stop upgrading and gear swapping for good. Along comes Iron_Dreamer's comment about attaching two single ended amps to create a truly balanced system with VDA2 DAC absolutely intrigued me. I then began crudely test the idea by hooking up the ZOTL and MPX3 in a "balanced" configuration with hacked up stock Senn HD650 cable to make it balanced TRS format. After careful volume matching on two amps...it had potential and warranted a further practical research and experiment. I had made a promise to my wife that I will NOT keep more than two amps at a time so ZOTL or MPX3 had to go and stay around $1000 budget. I hated the idea of selling the ZOTL but I had to give it up and find it a very good home. I found a perfect home for it. Then I stumbled onto John's little bass boosted cMoy and that along with Iron_Dreamer's idea sparked this whole experimentation, revelation, eargasm, and "never go back to single ended system" mantra.
BACK TO THE SOUND:
After few days of burning in the cMoy amps...I didn't expect much as I was playing Diana's Live in Paris CD on iTunes. What can I say, the sound was amazing, powerful, the details, the channel separation was ....just WOW!! I had to look over to the two Altoids tin cans with rubber band strap on it and I just had to laugh out loud. This sound just can't be coming out of that!!! No way...no how!!! I compared the sound with MPX3 and the balanced cMoy and the balanced cMoy sound fuller, more organic, powerful, the bass went deeper, more detail, better channel separation, the treble energy was better than the MPX3 with vintage Sylvania 6SN7 and KenRad 6SN7 tubes, which was considered to be the best 6SN7 tubes for my old MPX3 6SN7 system. What is going on?!?! How can this be?! I am absolutely addicted to the balanced sound. I heard balanced rigs at the meets but never impressed me too much because the meetings are not the ideal environment to listen anything critically.
Instead of questioning too much at my elation and eargasm, I immediately decided to sell the MPX3 to fund it towards purchase of a "real" balanced system....Headroom's Desktop Balanced with Home module and dedicated power supply. (I promised my wife I would not buy any more cans for 6 months..hehe) The bad news was I had to wait two weeks plus for Headroom goodies to be built and shipped to me. Few days later, I decided to take Iron_Dreamer's original idea of going with all CIAudio's "balanced" system with two VHP2 amps and VAC power supplies. I canceled the Headroom order. The VHP2s and VACs should be here very soon
CONCLUSION...NO REVELATION:
It's true...SennHD650 turns into a different creature with balanced configuration. The sound it produces is probably the best bang for the buck in any headphones costing below $1000. Match that value with John's two matching cMoys that cost less than $100, another $100 on decent cables and power supply for the cMoys and you got your self a great balanced system on the cheap as long as you have a balanced DAC and easily modded balanced Senn stock cable.
When I get the VHP2s soon, I am planning to send out John's balanced cMoys to others who have VDA2 DAC and HD6** / HD580 so they can also contribute to "balanced system on a shoe string budget" opinion. I am NOT saying here that balanced cMoys can beat a $1000 balanced system or even a top notch single ended system. This information is to share a great idea inspired by Iron_Dreamer's and great product made by John Seaber (aka blackinches) in action at a great price/performance ratio. For me, I absolutely love the balanced sound...I can't go back to single ended
Final thought...I just want to thank Iron_Dreamer for his spontaneous idea of going balanced with two single ended amps that inspired me and John's cmoy to make it all happen in the first place.
Fiinally, Head-Fi's first story that's happy for your wallet
Next stop... balanced custom mini^3