o...hardly any review availble...so will post what i could find, for anyone interested
"The ranking..."
"1) MEIER CORDA HEADSIX
2) iBasso D1 with OPA2111 LR amp, AD8397 buffers, AD8656 in DAC
3) Headstage Lyrix Total Pro
4) RSA Tomahawk - was previously tied for sound with Lyrix
5) PenguinAmp Caffeine with bass boost - was almost tied with tomahawk for sound
6) iBasso D1 stock"
"First, what I heard: Using the Headstage USB DAC I was able to plug the Lyrix directly into USB, and the Headsix into the USB DAC cable, and then I could quickly switch the sound control panel between the two to compare (having to move the headphones to the next jack at the same time). I then did the same with the D1, swapping it for the Headsix on the External USB DAC, connecting to the front audio input. This way all three amplifiers were auditioned with the Headstage USB DAC.
Each amp still had it's own flavor, but all all were so close it was hard to avoid having them all tied. The Lyrix really came into it's own with those extra hours on it. NONE of the amps had anything I would call flaws.
Mids and Highs: They all had smooth mids and highs with no grain to them, and plenty of detail. The Headsix had a warmer midrange, with the Lyrix just behind it. The D1 was a little cooler. I didn't feel the highs were rolled off on any of them
Bass: I did feel that the Lyrix could go deeper than the Headsix or D1, even with bass boost off. They all had tight punchy bass, but the Lyrix could really put it down if you hit the bass boost switch. Bass boost had NO distortion at all, adding just the right amount to the HD600's to give them some authority (Robert claims 6db, while the Penguin Caffeine was claimed to boost 8db on low gain and 9db on high gain).
Volume/Gain: The Lyrix in High gain mode also had the most volume available with the HD600's - after burn-in it seemed even louder, but i've not heard or read that being described before. The D1 has no adjustable gain, and seems to play about as loud as the Headsix which was also in High gain mode.
Hiss: I put on my Denon C700 IEM to test hiss (Livewires were out in the car, and SE530 are being experimented on). The Headsix was the quietest, The Lyrix was just behind it when in Low gain, but had a bit of hiss in high gain when the volume was turned up. The D1 was in between.
Listening to a couple of jazz tracks, "Traveler" and "The Walk", by Guinea Pig off the "Kool Cats" album: This is a nice "studio" album with just the right amount of echo or ambience mastered into it, except for an occasional cymbal hanging too long, or such.
The Lyrix showed it can walk and chew gum at the same time. The soundstage was more forward, yet each instrument had it's own space. The dueling Saxaphone and Trombone each have their own place on the soundstage, with Sax on the left and Trombone on the right, and the rest of the band around and inbetween them. They weren't totally one sided, like some old Beatles songs, but maybe one 45 degrees off to the right, the other 45 degrees off to the left. The crossfeed switch did center these a little bit more, but I preferred it without crossfeed as some of the ambience is lost when it is active.
The modded iBasso D1 was very similar to the Lryix, and certainly not as distant as the stock D1, but still with a little thin-ness (not good), and more airyness (good) and less weight (not good) than the Lyrix. Reassuringly, this was similar to how I had remembered it, but the changes in the Lyrix with burn-in allowed it to pass up the modded D1 just a little.
The Headsix seemed to blend the two instruments a little more to the center (without a crossfeed circuit to do that), having a slightly smaller soundstage with the Sax and Trombone being much closer than to the listener than the rest of the band - so the soundstage was less wide but was deeper than the other two. The ambience or air around the instruments was so very slightly less than the other two, but the "breathyness" of the Saxophone was slightly more intimate than with the other two.
I also listened to a couple of jazz tracks, from the "Jazz at the Pawnshop" album, paying attention to the woodwind, piano and drum solos, along with the clinking of silverware and talking between individuals in the background: The Headsix, Lyrix and D1 all seemed to do the piano with equal aplomb, with only a slight difference in seating distance from the piano, but the drum solos, vibraphone and saxaphone were different.
The Headsix seemed to put the listener inside the tomtom at times, and certainly it felt like the listener IS the drummer most of the time during a solo. When the solo is directed to the Woodwinds, Piano or String Bass then the drums move back to the stage, and the new solo instrument is handed to you to play instead.
The same thing happened with the vibraphone, making you feel like you were right under the tubes being banged on.
The Lyrix and modded D1 don't overpower you with the drums or vibraphone, but still seem to surround you with them - you can close your eyes and decide whether you want to pretend you are playing, or whether they are a couple of feet next to you as just a listener. Saxaphones are always being played next to you but not played by you yourself, unlike the Headsix.
With the Lyrix and D1: On one track the crowd talking in the background seems to be around you and more present, while with the Headsix the ambience is lost a little to the more forward instruments and solos. That does allow you to focus more on the music itself, but the aura of the venue is not quite as present as with the other two.
Diana Krall, "Girl in the Other Room", Temptation and Departure Bay tracks: I felt we needed some female vocals here, and there was also some nice string bass and piano to sample as well.
They all demonstrated a clean attack with string bass and pianos, with as usual, the Headsix being a little more intimate and close up. While that is not as enjoyable listening to music that belongs in a larger venue like Jazz at the Pawnshop, here it brought me closer to being in a small lounge with a glass of cognac and a cigar, so to speak. Her breathy vocals are just a bit more present and "vibratory" with the Headsix, but the Lyrix and D1 both do a very good job as well. When there is no artificial echo, reverb or ambience added, the differences are not as great.
Dave Matthews Band, "Live at Red Rocks - 8/15/95", Proud Monkey: I thought with the differences in presentation or depth of soundstage being the main distinguishing characteristic of these amps, then lets go for a REALLY BIG venue. The Headsix seemed to give a good balance to this particular recording, with the far spread crowd lending a large size to the venue, but not masking the vocals. The Lyrix was second best, with the vocals a little more distant and not rising above the crowd as well as the Headsix did, whle the D1 was very close behind it. The recording itself wasn't good enough to feel like I was really there with any of the amps, unfortunately. I probably wont use this material for testing again.
Finally: What I heard using the iBasso D1 USB DAC: I used the iBasso D1 hooked up to the Macbook USB, and used it to drive the Headsix and Lyrix, as well as the D1's own internal amplifier. All three amps sounded a little more open and airy, transparent if you will, when using the D1 DAC vs the Headstage DAC. The gap between the two DACs does not appear to be as wide as it was before, since the Headstage DACs have burned-in now. And, the gap did not get narrower because the D1 DAC sounds worse, but rather because Headstage DAC's sound improved (internal and external).
Hmmmm. I listened, and listened, and listened, and somehow the amps respond to the D1 DAC differently now that it has the AD8656 in the DAC instead of the AD8616. Before, in my first post, the "sonic signature" of each amp was noticable whether I used the stock D1 USB DAC or the Headstage USB DAC. Certainly in this post so far, the amps behave differently, primarily in the area of soundstage.
Yet, it was much harder to tell the amps apart when driven this way. :blink:
As a lark, I plugged a Y-splitter into the D1's DAC output (aux out) and ran the signal into both the Headsix and the Lyrix at the same time. I listened to one of the amps as I plugged the Y into the other, with almost no change in sound when the DAC was driving two amps. So far so good.
Now it was a simple matter of plugging the HD600's into one amp, listening, then plugging it quickly into the other amp to listen. This helped to get a fast change between the two, without having to unplug a cable from one amp and plugging it into another at the same time as switching out the headphone jack. I did have to unplug the DAC output cable from the D1 BEFORE plugging the headphones, but no big deal.
(If I were to plug in all three units into USB hub at the same time, to switch I would have to (1) click on the Macbook sound control panel to switch between the D1, Lyrix internal DAC and Headsix with external DAC, and (2) still unplug headphones to switch to another amp. More steps = slower switch.)
So, with D1 DAC outputting to the Lyrix and Headsix at the same time, moving the headphones from one to the other SOUNDED THE SAME, with the Headsix being a little less forward, and the Lyrix being a little more forward, and meeting each other in the perfect middle.
After 10 minutes, I gave up trying to pick which one sounded better, and started listening to the D1 amp vs the other two - which sounded equally as good, if maybe a little more open. :stoic:
That is the Suprise Ending. I am soooo tempted to want to ship these to Skylab or HiFlight or Mraroyo to try repeating this test and see if my mind is playing tricks on me (or should I say "ears"), but I can't bear to be without them.
RANKING OF THE AMPS WITH HEADSTAGE USB DAC:
1) Headstage Lyrix - tied. Better with some material, but not all
1) Meier Headsix - tied. Better with some material, but not all
3) iBasso D1 with modded opamps - still just a slight bit more distant, analog in not as good as built-in DAC.
4) Tomahawk (was already burned-in, not retested)
5) Penguin Caffeine - almost tied with Tomahawk and so close I keep changing my mind, but Tomahawk's size wins (was already burned-in, not retested)
6) iBasso D1 stock opamps - left behind in the dust, but still an excellent amp but maybe a little shrill at times - synergizes great with SE530 and HD600 with stock cable.
RANKING OF THE AMPS WITH iBASSO D1 USB DAC:
1) iBasso D1 - ever so slightly improved air and transparency to the music.
2) Headstage Lyrix - tied exactly with Meier Headsix, very close to iBasso.
2) Meier Headsix - tied exactly with Headstage Lyrix, very close to iBasso.
3) did not retest Tomahawk and Caffeine
4) iBasso D1 stock opamps
"
(...smeone give some tips