Acoustic Frontiers - Design, Build and Calibration of High Performance Listening Rooms and Home Theaters.
As I stated before, the clicking stopped completely when I minimized the windows of the Amarra player. Apparently, the active meter display takes a lot of CPU to run. My Mach2 Music MacMini server has undergone extensive modifications to reduce unwanted background processes from interfering with the primary function of being a music player.
I notice the initial poster was using a Weiss Int202 (firewire) so it comes back to application layer/resources as you mention and USB CPU utilisation is not part of the issue.
Interesting they also use an Apple Mac mini, wonder if this happens with their pro models as well - but that does not help you and only helps to narrow down the extent and type of issue specifically around the application layer/resources including CPU utlisation.
I found your experience with the setup of your digital system using a Mac and Krell really interesting. Since I own a Krell S1200 too, I followed the same thinking you did and that was to utilise the DAC in the Krell S1200. I have compared My Esoteric CD player (DV50) DAC to the Krell DAC, and found the Krell DAC much fuller, warmer and more definition in the bass. I actually tried the Olive which sounded good, but the remote interface was clumsy. So I bought the Bryston BDP-1 (Mac mini too complicated for me) which is outstanding and also connects to the Mpod remote app. For what its worth I also hooked up the Bryston BDA -1 DAC to the Bryston BDP-1 and fed the analogue signal through the Krell preamp section. However after some comparisons and AB teststing I still preferred the Krell DAC which is just outstanding. So although using the Krell DAC via the coax out from the Bryston is excellent, I too found the issue with Krell's inability to play higher than 24/96 through the coax. I called them and their answer was to use the HDMI cable input which I cannot with the Bryston. So I found your comment that - "I later discovered that the Krell wouldn't accept 24/192 via its coaxial inputs (they are releasing updates to correct this)" - of great interest. Has there been any software upgrade for the Krell? I am not optimistic, but you never know...... BTW the hi res downloads from HD Tracks are great for digital playback.
Welcome to WBF, Howard!
The Krell S-1200 (at least mine did, which shipped in Jan 2011) requires a software update that allows the unit to accept 24/192 from MacIntosh computers. Something in the "handshake", I imagine. PC-based sources do not have that problem, from what I've been told.
Krell is currently working on an update to allow its coaxial inputs to handle 24/192 signals. I will certainly post here when I get news of its availability.
HDMI into Krell from MacMini VS. MacMini > USB > Calyx Audio DAC24/192 > Purist XLR > Krell B1 input jacks
Several of us listened to this comparison, and universally preferred the outboard DAC method. Regardless of who did the switching, or what was playing, this was the constant sentiment. The Calyx DAC (review coming soon) uses the same ESS Sabre DAC chip that the Krell does, so there is a similarity to the sound. The external DAC sounded more harmonically complete and had better bass (levels matched closely, but probably not perfectly). The difference was large enough for all of us to consider it a "no-brainer" in my system. Your setup may or may not demonstrate this same behavior.
HDMI VS. Coaxial into Krell with CD transport
Here, we all preferred the HDMI connection. The coaxial input sounded bloated and showed less detail. Instruments, from lute to trumpet, sounded more realistic via HDMI to us. I was using the coaxial output of the Denon 3800 Blu-ray player and its HDMI output for the comparison. I don't own a "high-end" CD transport. It's possible that the software update for the coaxial inputs may change the sonic presentation, and I'll certainly revisit the comparison when I install the update.
I hope these brief comments were of some help.
For what it's worth, I'm fairly over the hump on the learning curve for using the Mac computer for audio playback/storage. I've now got about 1/2 TB on my drive, and have left room for the inevitable accumulation of high-res files in the near future (salivating).
Don't be intimidated, if I can do it, you can too. That's why I detailed the struggle, as I was coming from a near-illiterate position on computers, etc. There is a wealth of help here, and some great people providing it. For that, I am deeply grateful.
Thanks Lee. Very helpful info.
I will keep my eye on your posting for that Krell COAX upgrade!
The updates are installed via the rs232 port on the Krell, and your dealer will need a computer that can handle the update file AND adapt to the rs232 port. I can give you the phone number of my local dealer who has the right setup to accomplish the hookup if you need it. They can email the details to your dealer if necessary.
That would be very helpful.