Exchange tips and tricks for the Akai MPC4000
By pask Tue Apr 28, 2020 7:55 am
dabmeister wrote:
For the two decades I've been dealing with digital audio, I've always understood that "word clock" and digital audio were two different entities. One focuses on the AD/DA converters, the other deals with the subject matter "audio". Word Clock just keeps the sample rate for the converters in line or sync'd, so that the audio stream won't get any audible artifacts such as clicks, pops, aliasing, etc.


My understanding is that any digital device has a clock: PCs, Macs, drum machines, samplers, microwave ovens, etc.
The clock is supposed to keep calculations in sync, and not just at the AD/DA stages.
The better the clock, the less jitter (lack of precision). This is why some audio engineers pay big money for high end clocks like the Antelope atomic clock.
The sounds is clearer, more focused, tighter, more defined, the soundstage is usually larger, the bass goes deep without getting muddy, the high end is more refined, etc.

For example, you can run the same ProTools session with the same DA stage and hear differences when switching clocks (I’ve tested it for myself).

So, the MPs definitely have a clock that has an impact on the sound and I was curious as to listen to them slaved to an external one.
But there is no evidence so far that this is possible.

ADAT and AES digital audio are able to carry the clock signal alongside the audio, which SP/DIF doesn’t (thus, probably, the WC option on the SP/DIF card).

It seems to me that the 4k was designed to function as the master but not the slave.
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By CharlesRandolph Tue Apr 28, 2020 10:01 am
pask wrote:
My understanding is that any digital device has a clock: PCs, Macs, drum machines, samplers, microwave ovens, etc.
The clock is supposed to keep calculations in sync, and not just at the AD/DA stages.
The better the clock, the less jitter (lack of precision). This is why some audio engineers pay big money for high end clocks like the Antelope atomic clock.
The sounds is clearer, more focused, tighter, more defined, the soundstage is usually larger, the bass goes deep without getting muddy, the high end is more refined, etc.

For example, you can run the same ProTools session with the same DA stage and hear differences when switching clocks (I’ve tested it for myself).

So, the MPs definitely have a clock that has an impact on the sound and I was curious as to listen to them slaved to an external one.
But there is no evidence so far that this is possible.

ADAT and AES digital audio are able to carry the clock signal alongside the audio, which SP/DIF doesn’t (thus, probably, the WC option on the SP/DIF card).

It seems to me that the 4k was designed to function as the master but not the slave.


SP/DIF carrys both the clock and audio signal, it just not ideal. The only time I find digital clock useful is in video work. But if your gear has good internal clocks, you really don't need them. Unless you're sync lots of digital gear.


pask wrote:That seems to be an output (to slave ext gear to the MP’s clock), not an input.


Yes, I misread what you're asking.
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By CharlesRandolph Tue Apr 28, 2020 10:33 am
NearTao wrote:You know... I had actually burned word clocks from my memory and forgotten all about jitter and such.

I want to say thanks for all the great posts reminding me of my advanced age memory gap, and also recalling how much I disliked dealing with BNC connectors and termination issues. I had a BNC run long enough that I was getting device reflections and all kinds of other problems. So don't run it too long :D


Agree, it's best to keep the run as short as possible. No more than 2 meter, but you have to check the clock specs.
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By dabmeister Tue Apr 28, 2020 12:15 pm
The use of my Apogee Big Ben is to sync anything I have that may be suspect of (previously mentioned artifacts). It use to be where clock gens were "really" necessary due to the lack of precision with the internal clocks of older gear. Fast forward to now, things have improved ten fold, but not to the point where you'll never need some sort of master sync device. Gear will always change as time goes on. So many manufacturers adapt to these changes through better technological advancements with their products. That being said, that's why we have a choice in using various products from different companies, but with the option of allowing them to work together to get the best "sound" possible. Me personally, and if my pockets can afford it, I want some of this new "sync" stuff out here to better my sound. PS...I don't have the SPDIF/WC card in my 4k, but I do have the adat card.