• surdo
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  • Registered: 2013-05-13
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Topic: Extra 8 channels with Multiface I

Hello,

I've had a Multiface I and hdsp pci card for many years. I presently need an extra 8 channels of output for an installation. I understand that an extra multiface unit can be linked to the multiface/hdsp without the necessity of a new hdsp card - however I won't be able to use the higher sampling rates because of ADAT limitations and also that the set up becomes a bit more fiddly.

So - I'll be likely to purchase a new multiface II unit and new HDSP PCI card from a local distributor (hard to come across 2nd hand units in this country).

My questions:

Can I combine a Multiface I/HDSP PCI with a Multiface II/HDSP PCI?

Is it necessary to use cabling to synchronise the two multifaces?

If so, what or which cables are necessary?

Thanks!

  • Jeff
  • Jeff
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Re: Extra 8 channels with Multiface I

surdo wrote:

Can I combine a Multiface I/HDSP PCI with a Multiface II/HDSP PCI?

Is it necessary to use cabling to synchronise the two multifaces?

If so, what or which cables are necessary?

Yes

Yes

Word Clock, SPDIF or ADAT

Regards,
Jeff Petersen
Synthax Inc.

Jeff's Website

  • surdo
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Re: Extra 8 channels with Multiface I

thanks!

  • From: Houston, TX
  • Registered: 2007-05-11
  • Posts: 1,191

Re: Extra 8 channels with Multiface I

FYI - The MF-I and MF-II's AD/DA conversion latencies vary slightly (MF-II is slightly quicker) - you won't get "Sample accurate" I/O across MF-I to MF-II.  This is generally only an issue if spreading mics on a common source across the two units (like Overhead Left on MF-I and Overhead Right on MF-II; or Guitar Amp SM57 on MF-I and Guitar Amp R-121 on MF-II).

Shouldn't be a major issue for most people, but something to be aware of...

cool

MADIface-XT+ARC / 3x HDSP MADI / ADI648
2x SSL Alphalink MADI AX
2x Multiface / 2x Digiface /2x ADI8
  • surdo
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Re: Extra 8 channels with Multiface I

Oh, thanks. I think it will be a problem then - I'm planning a 12 to 16 channel ambisonic spatial audio project. Ambisonics uses all channels to spatialise any given source.

Would two Multiface Is sync perfectly?

  • From: Houston, TX
  • Registered: 2007-05-11
  • Posts: 1,191

Re: Extra 8 channels with Multiface I

I believe using two MF-I's (each on their own PCI card) would be sample accurate across units.  RME would need to confirm there are no internal offsets when stacking multiple units under the common driver.  You'd also be using identical converters which might also standardize your performance across units.



cool

MADIface-XT+ARC / 3x HDSP MADI / ADI648
2x SSL Alphalink MADI AX
2x Multiface / 2x Digiface /2x ADI8

7 Reply by surdo (edited by surdo 2013-05-13 21:22:26)

  • surdo
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Re: Extra 8 channels with Multiface I

another complicating factor may be that I run Linux. RME?

  • From: Toronto
  • Registered: 2007-05-01
  • Posts: 95

Re: Extra 8 channels with Multiface I

Why not get an OctoPre or something similar and use your ADAT to add the 8 channels?
1PCI card, 1 MF, 1 8xPre, 1 Total Mix, no futzing in Linux to combine units, Simplicity. Not to mention cost.
Or do you need to go above 48Khz?

9 Reply by Randyman... (edited by Randyman... 2013-05-14 00:38:47)

  • From: Houston, TX
  • Registered: 2007-05-11
  • Posts: 1,191

Re: Extra 8 channels with Multiface I

You will still need to account for the varying offsets from the MF-I's AD/DA's to whatever external AD/DA you will be using.  I believe the ADAT I/O also adds a sample or two of latency of its own.  Generally not a huge issue as mentioned, but for stuff like what surdo is talking about, I believe it needs to be sample accurate or bust.

This feat ("sample accurate" across multiple units) is actually pretty hard when linking multiple AD/DA units.  I specifically added an ADI-648 to my MADI setup to allow both of my SSL MADI Alphalinks to be sample-accurate across units (no ADAT-to-MADI latency from the SSL Alphalink's own ADAT-to-MADI interface when SSL#2 used to feed SSL#1 over ADAT;  Both SSL's now interface to the ADI-648 via ADAT - sample accurate across all 48 I/O's!).

I'd like to see a new revision of the ASIO standard that would allow a way to specify driver offsets per I/O channel - would really clean up this issue!

cool

MADIface-XT+ARC / 3x HDSP MADI / ADI648
2x SSL Alphalink MADI AX
2x Multiface / 2x Digiface /2x ADI8
  • vinark
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Re: Extra 8 channels with Multiface I

surdo wrote:

Oh, thanks. I think it will be a problem then - I'm planning a 12 to 16 channel ambisonic spatial audio project. Ambisonics uses all channels to spatialise any given source.

Would two Multiface Is sync perfectly?

I doubt (read I am sure not) the differences of a few ms will be a problem in this setup. Unless you bolt a 1 man audiences head to a fixed point, delays will vary much more through the venue.

Converter delays can be an issue when recording one complex source with multiple mics over different converters.

Vincent, Amsterdam
https://soundcloud.com/thesecretworld
BFpro fs, 2X HDSP9652 ADI-8AE, 2X HDSP9632