[Andrea]

Yesterday night I listened to a current favorite of mine, Nick Cave's Abattoir Blues,

and I was enthusiastic at the sound! This amp makes the HD485 sound like a higher end can -- viscerally deep and perfectly articulate, dynamic, bass; a lifelike and refined sounding midrange; and a treble again full of life and of small subtleties. All in all, a mostly evenly balanced, effortless, "big" sound.

None of the other portable amps I've used as yet -- Portaphile X^3 with BUF634's and LT1210, Go-Vibe v4 with AD8058, Go-Vibe v5 (standard and modified), Little Dot Micro+ -- managed to do this much for the HD485. (the Go-Vibe v4 with AD8058 being my second best)

 

[Andrea]

Modified Xenos in good company (less the "shameful" interconnect...the "good one" is still on its way)

Modified Go-Vibe v4 in good (if likely temporary) company

 

[Andrea]

I felt like taking a new pic to celebrate the arrival of the new cable just a moment ago

I still have to listen but the build quality of the cable is great for the $24 I paid it with shipping...

 

[Andrea]

Looks like it'll have to wait tomorrow.

Meanwhile, I've found this review & details on the "Ultralink Discovery" cable on which this interconnect is based. Promising! http://www.hometheaterhifi.com/volum...erycables.html

 

[Andrea]

Even without burn in, the improvement made by this cable is most apparent. What already was a surprisingly big sound is now bigger still. More low bass, more high treble, more treble sweetness & detail; more midrange refinement, atmosphere, air, blackness... All in all, a sense of reduced distortion + improved extension.

 

[Andrea]

I briefly compared Go-Vibe v4 with AD8058 and Xenos 0HA-REP with AD823 + LMH6654, in my main system with the HD650... playing Nick Cave, No More Shall We Part...

I like the Xenos better; it's a bit more easy to listen to, not slightly dry like the Go-Vibe, and thus more fluid; has a little more midrange body and presence (the Go-Vibe has a tad distant and analytical midrange), and a slightly more full-bodied bass. Tonality wise they're both very good and similar; perhaps the Xenos has the colors a tiny bit more intense, perhaps. Both are great amps that sound natural and very clear, but if you ask me, I'd take the Xenos. Note that, like I said in a thread about this mod, I like the AD8058ed Go-Vibe v4 better than I ever liked the v5 standard or modified (and it's better looking, too).

 

[NelsonVandal]

I got a bit tired of the lack of energy from AD746, but I haven't got my AD823 or AD8058 yet, and I don't like to wait. I'm also awaiting the Xtra.

I ripped out the 746 from the input stage and soldered a crappy input cable directly to pins 1 and 7 where the op-amps outputs are supposed to be. Now I'm only using LMH6654 in the output stage. Now it's more fun to listen to. Maybe a bit on the bright side but absolutely without sibilance, harshness or noise. Great soundstage, clarity, details, transparency etc. Power enough for both my 600 ohm Senns and my 32 ohms Philips. Good synergy with both.

Do I really need an input op-amp? Is this mod dead wrong? Is it a total electric mismatch? Am I just biased to think it's good?

 

[Andrea]

Err... just answered in your DIY forum thread, too lazy to copy-paste...

 

[NelsonVandal]

Now the buffers are gone and in is AD8397. I just wanted to listen to it without the LMH-amps. Now it's back to the typical Analog-sound. More impressions later.

 

[Andrea]

I'm curious to read them...

If you leave the AD8397 in, you might consider removing & jumpering the two 100uF 16V electrolytics. These are used to reduce DC offset, but the bufferless AD8397 probably won't require them -- and I remember I suspected that they were decreasing the bass somehow (with the lone AD8397), though I wouldn't bet it.

 

[Andrea]

Quote:

Originally Posted by Andrea I was just one step away... So now I've the AD9631's too in the Xenos. Still have to listen, but one thing I can tell for sure: powered with 12V, they don't run cool The top of the amp gets a bit warmer than even with two AD8397's inside. I think I'll keep the voltage a little lower, i.e. 9V for now, and maybe 10V later.

Quote:

Originally Posted by Andrea I'm left absolutely SPEECHLESS. This is IT. The sound has suddenly turned heavenly, breathtaking, perfect. And what do I care if it gets a little bit warm, when it sounds this good. I'll keep 12V (previously I was overly cautious, I believe). The first two songs of Beth Orton's Central Reservation, like all of an usual favorite, Rainy Day Music by Jayhawks, suffice to prove that this is the most perfect sound my HD650 has ever delivered.

.

 

[NelsonVandal]

AD8397 went out and LM4562 went in again (without buffers). I don't think I'll ever like the typical Analog-sound. Harsh treble, flat bass, over all a cold sound, but good soundstage and speed though. I think this is a very fatiguing sound that will always make you look for errors in your system, make you buy expensive cables, PSU's and even other amps just for variation. You could be impressed when a recording is a perfect match, but if you listen to many different recordings you'll learn to hear the mentioned Analog sound.

The LM4562 is also coloured. It's a bit too much of everything people like about Hi-Fi - clear and open highs, wide mid, sweet bass. A bit hollow and sterile. Another guy on Head-Fi called it echoing. It's fun but not natural.

I'm not sure what buffers to use. I might go for Andrea's new baby, AD9631. I'm also interested in a discrete buffer like sijosaes "diamond buffer". Other options are BUF634 or TPA6120. Maybe I'm going back to "nope-amp" (ie bypassing the input amp). So far this was the best setup in my Xenos, though a bit bright due to the LMH6654's I think. What ever I do, I'll probably will have a bypass switch for the input opamps.

Right now this amp falls short of the cheaper Xtra X1.