Clock Synch in MCH System

edorr

WBF Founding Member
May 10, 2010
3,139
14
36
Smyrna, GA
I finally got my MCH audio system up and running. I run Dirac on a server, lynx card out into MSB DAC IV for mains, and 2 x NAD M51 for center and surrounds.

I am running into maximum gain limitations because my center channel is very low sensitivity, which restricts maximum gain of the entire setup. I am contemplating getting DACs with higher output voltage for center and surrounds (NAD is only 2V), and have my eyes on the Myteks (10Volt max). This would buy me at least 10 extra dB.

While exploring this option, I noticed the Mytek has word clock in / out and clock synch, so this may open up some interesting clock synch options. my Lynx card has clock out, so I could use this as a masterclock for the Myteks - the MSB would not be synch'ed.

However the MSB also has a clock out through the I2S interface. The documentation says: "The interface is a LVDS format clock interface with a signal level of 250 mV pp."

Does anyone know if I could use this MSB clock as the masterclock for the entire MCH setup and use it as clock input for the Myteks and the upstream Lynx card? Any other suggestions what I could do to synch up clocks with the hardware (MSB / Lynx / Myteks), and if this is even worth doing?
 

edorr

WBF Founding Member
May 10, 2010
3,139
14
36
Smyrna, GA
You could link three Mytek Stereo192-DSD DACs for Multichannel or use one of their 8x192 8 Channel Professional DACs.
http://www.quadraphonicquad.com/for...-DSD-playback-solution-with-Mytek-and-J-RIver!

Another option would be the exaSound e28 which is an 8 Channel DAC with resolutions up to quad DSD (DSD 256).
http://www.exasound.com/e28/Overview.aspx

Thanks, I'm aware of these options, but I want to integrate 2 Myteks with my MSB for mains. I am getting some indication it might just work (use I2S Pro to BNC adaptor, and feed wordclock to one Mytek and then daisy chain it), so I'll get the hardware and give it a whirl.
 

Ivory

Well-Known Member
Aug 11, 2011
14
0
76
I'm considering a similar options, I have a 8ch DAD AX24 and I would like to try an MSB for the main channels. I think that the output clock from the I2S from the MSB should be working to drive other DAC's, but the problem could be a different delay between different devices. If the delay is constant, it could be compensated, but I'm worried that it may change while playing.
 

edorr

WBF Founding Member
May 10, 2010
3,139
14
36
Smyrna, GA
I'm considering a similar options, I have a 8ch DAD AX24 and I would like to try an MSB for the main channels. I think that the output clock from the I2S from the MSB should be working to drive other DAC's, but the problem could be a different delay between different devices. If the delay is constant, it could be compensated, but I'm worried that it may change while playing.

The word-clock out from MSB does not work yet. In fact, they are sort of proposing to develop it with me as beta tester, running the clock into Mytek DACs and Lynx card.

The MSB has delay in reclocking mode, which cannot be used in a MCH setup. So simply turn off reclocking and you should be fine, unless your other DACs have systems delay.
 

mojave

Well-Known Member
Oct 29, 2010
251
0
321
Elkhorn, NE
You should gain 11.47 dB over your existing setup since you can now utilize the 7.5V maximum of the MSB. That will help out a lot.

Unless you use a master clock for all DACs, you may get some drift during playback. To test, use the MSB for the left channel and the NAD for the right channel. Listen to a playlist of several songs. Do the left and right drift apart at any time?

The MSB delay in reclocking mode shouldn't matter in a MCH setup since you can delay the other channels appropriately. Hmm, maybe the delay on the MSB varies from session to session.
 

edorr

WBF Founding Member
May 10, 2010
3,139
14
36
Smyrna, GA
You should gain 11.47 dB over your existing setup since you can now utilize the 7.5V maximum of the MSB. That will help out a lot.

Unless you use a master clock for all DACs, you may get some drift during playback. To test, use the MSB for the left channel and the NAD for the right channel. Listen to a playlist of several songs. Do the left and right drift apart at any time?

The MSB delay in reclocking mode shouldn't matter in a MCH setup since you can delay the other channels appropriately. Hmm, maybe the delay on the MSB varies from session to session.

The gain is limited by my center channel, which is driven by the NAD, so higher gain in the MSB (which would be about 3dB at 7.5v output setting, not 11dB) does not help me. Delay on the MSB varies by sample rate, so if I engage reclocking in MSB and I calibrate my MCH system with 48/24, channels would still be out of synch with other sample rates.

I'm going to play around with the MSB, my new Mytek, the NAD and the PS audio Directstream (I have four DACs in the house) try some clocking options (provided MSB figures out the word clock) see what works best, and build my MCH system accordingly.
 

bmoura

Well-Known Member
Sep 6, 2013
417
3
248
The gain is limited by my center channel, which is driven by the NAD, so higher gain in the MSB (which would be about 3dB at 7.5v output setting, not 11dB) does not help me. Delay on the MSB varies by sample rate, so if I engage reclocking in MSB and I calibrate my MCH system with 48/24, channels would still be out of synch with other sample rates.

I'm going to play around with the MSB, my new Mytek, the NAD and the PS audio Directstream (I have four DACs in the house) try some clocking options (provided MSB figures out the word clock) see what works best, and build my MCH system accordingly.

A house of DACs? Wow. I wonder if you could link/stack 3 of the DirectStream DACs for Multichannel - like the Myteks. Hmm....
 

edorr

WBF Founding Member
May 10, 2010
3,139
14
36
Smyrna, GA
A house of DACs? Wow. I wonder if you could link/stack 3 of the DirectStream DACs for Multichannel - like the Myteks. Hmm....

This (3 x PS audio) would be one of the three options. IF the PS Audio DS holds it own against the MSB for the mains, I would need to get three of them for my MCH system. The reason is the PS Audio has a delay (which varies with sample rate), so I cannot integrate it with other DACs in a MCH system, so if I go down the PS audio path I will need three.

The other two options are to keep what I have (MSB for mains, and NAD M51 for center / surround), or to replace the M51 with 2 x Mytek, allowing me to synch the clocks between, MSB, Lynx card, and Myteks.

I just thought of a good way to do a baseline DAC performance comparison. On my MCH server with Lynx card, I can copy channel 1/2 to channel 3/4, 5/6 and 7/8, so I can connect 4 DACs simultaneously to the exact same source. I can then run all four of them into my preamp and switch real time between four DACs. I can even do this blind by asking someone to switch sources on my remote for me.
 

About us

  • What’s Best Forum is THE forum for high end audio, product reviews, advice and sharing experiences on the best of everything else. This is THE place where audiophiles and audio companies discuss vintage, contemporary and new audio products, music servers, music streamers, computer audio, digital-to-analog converters, turntables, phono stages, cartridges, reel-to-reel tape machines, speakers, headphones and tube and solid-state amplification. Founded in 2010 What’s Best Forum invites intelligent and courteous people of all interests and backgrounds to describe and discuss the best of everything. From beginners to life-long hobbyists to industry professionals, we enjoy learning about new things and meeting new people, and participating in spirited debates.

Quick Navigation

User Menu

Steve Williams
Site Founder | Site Owner | Administrator
Ron Resnick
Site Co-Owner | Administrator
Julian (The Fixer)
Website Build | Marketing Managersing