Q. Should I buy a stand-alone master clock?

I'd like to know what the advantages and disadvantages are of using stand-alone word clock units, like Apogee, Lynx, Antelope, Mytek and so on, versus the old built-in word clock in a TC Konnekt Studio 48. I don't need many sockets (up to six, maybe) and I'm OK with daisy-chaining my gear as I do now, but would a separate word clock have many advantages over what I have now? I can put around £400 to £500 aside to buy something, if it's worth it. Via SOS web site




SOS Technical Editor Hugh Robjohns replies: If it ain't broke, why fix it? As a general point, running separately buffered clock feeds from a clock distribution unit is technically better (in terms of jitter and overall timing precision) than the daisy-chain technique. However, there's nothing fundamentally wrong with daisy-chaining either. And if it's working reliably now, there's no obvious need to change anything.



In general, converters (A-D and D-A) work better and deliver better technical performance if they run from their own internal clocks. Almost without exception, the measurable performance of most converters driven from external clocks is degraded, and the best you can hope for is that the degradation is negligible or minimal. Devices that process and pass only digital signals are not particularly critical of the clocking arrangements and quality is totally unaffected by moderate clock jitter.



So my usual recommendation is to use the internal clock of your 'master' A-D converter as the system's master clock, and distribute that via a dedicated clock distribution unit. The Drawmer D-Clock provides good value for money, for example. A master clock may well become necessary if working with external video machines because of the need to synchronise video and word clock. In this case, a good-value option would be the Mutec Iclock, shown here.A master clock may well become necessary if working with external video machines because of the need to synchronise video and word clock. In this case, a good-value option would be the Mutec Iclock, shown here.



If you're working with external video machines, then a master clock usually becomes a necessity because of the need to synchronise video and word clock, and in that situation I think the best value for money comes from something like the Mutec Iclock or Audio Design SynchroGenius. For the very few audio-only installations where a master clock is beneficial for practical reasons then, again, the Drawmer M-Clock boxes provide excellent value for money.



As I demonstrated in the article 'Does Your Studio Need A Digital Master Clock?' [go to /sos/jun10/articles/masterclocks.htm for the full article], the more expensive options like the Big Ben and the Antelope offered no detectable advantages in terms of audio quality, and few, if any, facilities that aren't available elsewhere for less.



If I were you, I'd invest that money in something else that would make a real, practical and tangible difference to your music-making activities.    

Published in SOS December 2011