Topic: Syncing a V3 Word Clock output with a DMIC-20 AES REF input

[Chuck]

Just curious how everything looks. I wondered how/where you would fit the toslink connector in there but, seeing that you removed the AES-XLR output, there's probably lots of room.

If only one could toss those dip switches...

As far as the DIP switches go, it is possible to completely eliminate them, but I am setting mine up to operate like a V3. The resistor network sets up the basic gain in 5 db steps (stock DMIC-20). Then I experimented with different values for the potentiometers and found that a 10k audio taper pot provides appox. 8.5 db for "fine" adjustment. I found the 5k pots (Todd Romero mod) to provide a little less than 5db of adjustment. I haven't tried 15 k pots yet, but that may just be ideal, putting the fine adjustment in the 10 db or more range.

If anyone is thinking about doing the gain pot mod, I have one more suggestion. I bought 5 of the Panasonic 10k audio taper pots and found only two that matched well enough for my use. Next time I will by more, so I have more to choose from for proper matching.

Also, the unit I bought had a busted phantom power section, so you may see some of my modifications to the circuit to fix that problem.

Chuck

[rowjimmy]

Looking good.
Although I'm sure the neutrik plate will be slick, It looks pretty clean as-is.
Nice work.
+t

I I know todd and have used a todd-mod dmic. I didn't have enough time with it to feel comfortable but my impression of the dip switches + pots was not the greatest.

Twas a good, clean sound, though.

[gratefulphish]

Reviving Part 2 of this thread, dealing with the issue of the R-4 Pro, using digital input via AES/EBU and also using analog input on the other two channels.

I finally got around to speaking to Edirol tech support about this issue, as I was concerned about the suggestions that using a V3 for the digital input would be governed by the V3 wordclock, while the analog inputs would be governed by the R-4 Pro's internal wordclock.  Tech support had to contact R&D in Japan for the answer and get back to me.  Apparantly, in the same way that the DMIC gets its wordclock from the V3, when you select digial+analog on the R-4 Pro, it then uses the wordclock of the incoming digital signal to control both the digital input, and the analog inputs, i.e. it's all run by the same clock, in this case the V3, so there will be perfect synching and no potential for drift.  Hope this answers any questions.

[Chuck]

I have made two recordings so far using the SPDIF out on the V3 connected to the AES REF input on the DMIC-20 and I am quite happy to report that the audio is in sync on the recordings made from both units. This is especially good, as I was working on an analog summing mixer to mix the two sources in the field (on the fly) because I didn't have the $$ for an all-in-one four track digital recorder. This is a much better solution. Now I can record with four channels or two channels as needed. Thanks for the great discussion. I learned a lot trying this for myself and reading what you all have said in your postings.

Chuck