QUOTE: "I'll try to do a comparison in couple days. I only listen to the w4s out of coax as the USB sounds dull to me. It does have a nice "analog" sound but I feel it is a bit dark and colored, not neutral. The highs are a bit rolled off which actually works fine with the HD800 as they are not fatiguing. I do however dislike that is very forward and punchy in the mids so vocals often sound shouty. I'm looking for a DAC that is a little more transparent and also more detailed as I find the w4s a bit fuzzy with the HD800."

 
Great answer and I'm excited to hear what you think of the PWD2...the NWD wasn't enough to get me to change over but I am hoping the PWD2 will have the warmth as well as the detail and extension that will make me switch.  Thanks for your impressions- DACs aren't easy to talk about, let alone that much info in a single paragraph.   

ship is going stax only.

Let me be blunt about the HD800.  There is no retail amp in existence atm that costs less than the HD800 retails for that will extract the full potential of the HD800.  I'd consider the S7 the entry point.  Maybe the BHA-1 for SS fans and depending on the time of day.  It is not a minimum expense rule, it is simply what the market has chosen to provide atm.  The same is likely true of DACs for the HD800.  I'd consider the M51 minimum standard.  If this is too much, then just buy a T1, LCD2r.2 or HE500 so you don't have to feel like you wasted your money on the HD800.

I really like the balance of my M51>Mjolnir>HD800 rig. The M51 solved all the gripes I had with the presentation when the Gungnir performed DAC duties.

Some have tagged the Mjolnir as bright and abrasive. I don't find that to be the case and have always maintained that it's just the amp magnifying deficiencies upstream. The Mjolnir can be lively and I can understand some preferring a more polite and laid back presentation. I don't think it significantly curtails the HD800 in terms of sq.

Can you elaborate on the Mjolnir's deficiencies compared to the S7 and BHA-1?

Anybody heard the Atoll DAC200?

I thought purrin posted something somewhere.  Either here or also at the other site.  I can't speak too much to the Mjolnir as purrin ninjad it before I got to audition it properly.  I heard two different sounding BHA-1s.  If I find the thread I'll link it, hopefully someone else does.  I'm actually working atm believe it or not. 

Still waiting on a response to my last question. Can anyone familiar with these amps (MJ/S7/BHA-1) provide some insight?

purrin?

Anax?

Anyone?

Crickets.............tumbleweed........

Tonal Balance:

Old S7: Slightly bassy and thickest of the bunch.
New S7: Cleaner, more liquid, and faster than old S7.
BHA-1: Slight warmth in the bass with good mid-high treble edge and definition, but not in bad way.
Mjolnir: Probably more neutral than any of the above. A little bit forward relatively. Sharper in the lower treble, but not in a bad way. Yet also strangely laid back (contradictory and hard to explain.)

Microdynamics and microdetail:

S7 wins by a mile. Well recorded is classical chamber or solo reveals this. S7 speed is faster. Attack of strings, etc. is more precise with more speed.
Mjolnir is better at microdynamic rendering than BHA-1.
BHA-1 and Mjolnir micro-detail is equal with a capable source running SE. BHA-1 Mjolnir pulls away in microdetail with a capable source running balanced.
S7 is the least flat sounding with the best microdynamics, followed by Mjolnir.

Macro-dynamics, bass, control:

BHA-1 has a tad more mid-bass presence.
Mjolnir has more explosiveness and slam in bass than BHA-1. About equal or possibly superior to the S7. Control exceeds the S7 a bit, especially in the lowest bass. New S7 may be closer.

Other notes:

BHA-1 (operating incorrectly): Slightly ill-defined and imprecise throughout the audio band. Bass, mids, treble. You name it.
Mjolnir: I don't believe in burn-in, but leave it on for 120 hours before use.
S7: Impressions of the S7 may be all over the place, b/c Anax's S7 is specially modded.
BHA-1: has better stage depth than Mjolnir and possibly S7.

Tonally, I prefer the BHA-1 with the HD800. Mjolnir is less flat sounding akin to tubes (closest to tubes for any SS I've heard.) I don't have HD800s anymore (or if I did, I would mod them and try out non Senn cables), so problem solved. Generally, the tonal balance thing I don't care that much about because there are usually methods to get around them, i.e. mods, EQ, cables, source. In other words, tone is correctable. Treble edge to a degree is also correctable. Flat microdynamics or lack of plankton retrieval is not correctable.

Most people go the other way. Find a good tonal match. A lot will depend upon recordings and source.