Hi Flecko, using DAP, Q1=1, I've never been able to go lower than 2048 with the Hiface, core appointment scheme2. With scheme 3 I can sometimes use 2048 but more often 4096.

Given the posts in this thread I finally listened to 9-z1. (It had given me problems before cause I had 2x arc prediction ticked and it got all tangled up in a 24/96 file). Well, it seems that the sound of z1 improves zb, but I'm really wondering if anything was explicitly done to change the sound of z1? Afraid I was being seduced by the power of suggestion in this thread, I ran the WIFE TEST. Didn't take her long to conclude that Z1 is more "natural" than zb. Now, as we all know, the wife test is not always correct (don't tell her I said that) but in this area fresh ears are helpful.

To me the mid range of z1 is more resolved or firm, less "breathy" sounding (distortion?) with the female vocalists: Patty Griffin, Tomorrow Night, from 1000 Kisses; Sarah K., Vincent (16/44 version), Alison Kraus, Baby, Now That I've Found You. It seems that something is lost in z1 but it does sound more "correct."

I A, B, C'd between 9y-8c, 9zb, and 9-z1.

Hope I'm not crazy..... you can keep your opinions to yourselves....

Here are the log files from that last successful effort, scheme 2.

Might just be. But I just tried those flac files of the same track in Scheme 2 and they played, 24/96 to 16/44. WTF 

Same problems with Scheme 2.

Yes, am having trouble with "daily" playlists too (mixing 16/44 and 24/96 tracks). Going from  24/96 wave to  16/44 wave caused the sound of the 16/44 track to be "under water" followed by too many buffer errors. Earlier this morning when I was trying to compare versions of the same track I was using flac files. Logs of both sessions are attached. I have a feeling this might have something to do with switching to Scheme 3 several days ago. The sound seemed better but I started getting a lot more "Engine 3 won't start" error. Will switch back to scheme 2 now and see if that makes a difference.

Log files in 5 am hr were with the two versions (flac) of the same file. 7 a.m. hour was regular playlist.

One other thing. Though I did not have log activities ticked, 9zb was logging activities anyway. Sorta surprised me.

Yesterday, I tried to compare 16/44 and 24/96 versions of the same file. Played the 16/44 file for about 30 seconds (all in unattended), stopped play and started play with the 24/96 file (I did not use alt/n to change to the 24/96 file). After the gui disappeared I received engine 3 stopped working errors, which is usually overcome by hitting alt/p again or by alt/x and then hitting play again. Alt/p generated the engine 3 error again so I hit alt/x and though XX appeared in the lower left side of the task bar the gui did not appear. Rt clicked and closed the xxtaskbar indicator and hit alt/x again but still could not get the gui to appear. Finally had to reboot. Went through this procedure again with the same result: reboot. This was the first time the gui totally failed to appear. I have had it not appear and then on a second try it does.

This morning I loaded the files again and tried to let them just play through. The 24/96 file was first. 4/5 of the file played and then I received the engine 3 error and sound stopped. This was followed by the Device allocated but cannot play error and a reboot. I have not tried 9-z1 cause I had many, many errors like this when 9z1 was first released. Just playing 16/44 files or just playing 24/96 files works fine.

Let me try this way: Why not put PE under the hood so it's always on?

Just wondering.....since peak extension works will it go away as a checkbox? I mean, when would you ever not select it, and, if there is never a time, why a checkbox for it?

Clueless in Philadelphia 

No applause, just throw the $$$$$

Does peak extension have any influence on the sound, other than volume, when playing a track that is not HDCD? Non HDCD tracks seem to sound beter here with peak extension ticked, but that just might be because of the reduced volume sounding "more resolved". Without being able to precisely measue the volume difference and add exactly 3db, IIRC , its hard to tell. My impression, guestimating the difference and trying to correct for it, is that  everything sounds better, less HF distortion at very high volume, with peak extension ticked.......Again, is this possible with a non HDCD track?

Thanks Bill. Here's a link to a modded Musiland by the DIY guys. Its the Cleo; looks very interesting for the price:
http://show.audiogon.com/cgi-bin/st.pl?DIY%20Digital&1&aline&Diyhifisupply

So you are using quad arc prediction to get the 176. That's great. Can't believe I was told that XX would not work with the Musiland ASIO drivers.

I am wondering what you mean when you say, "and my files play with the Musiland control panel" ? Is this something that you set before using xx or is it open simultaneously with xx?

So, you are beating the pants off the DACMagic?

As you probably know, Peter is developing a dac specifically for XX. I'm sure it will be among the very best, if not the very best. Cost though will probably keep it out of reach here for a while so I keep looking for an affordable alternative to get to quad arc prediction! Thanks for posting.

Thanks for those links, Roy. I'd never heard of Achmed before. Very funny.

Peter, glad to inspire such lofty sentiments in you. I shall spend my days thinking up new ways to torture you with the issues that arise from blazing a low to mid-fy (wishful thinking perhaps) trail through the rarefied air of XXhighend! 

Happy hunting indeed. The work at Guantanimo is classified.....no sh*t. Ha!

Thanks. I'll have a chance to get back to it, hopefully, this evening.