TOPIC:

Dear All

Here is a little trick for those of your looking to feed two (or more) miniDSP 2x4HD via USB Audio.
- Under Mac OSx, it's obviously not an issue thanks to the brilliant OSx aggregate feature. Thanks Apple!

- Under Win OSx, it just requires a bit more work. Here is what you will need:

1) Download Jack Audio for Windows (www.jackaudio.org/downloads/) and install it.

2) Download ASIO4ALL drivers from here (www.asio4all.com/) Select ASIO4All as audio interface inside Jack software




3) Aggregate the two audio devices using ASIO4All as per the attached screenshoot.




BOOM! You're now streaming digitally to both units via USB Audio.

NOTE: Control will still need to happen one unit at a time. Our plugins not having the ability to TUNE 2 systems together.

Have fun!

DevTeam

Hi,

Thanks for the guide! However it is very incomplete.

A few things:

1. Can you clarify the instructions for aggregating on Mac OSX? I didn't even know USB audio worked on OS X because it didn't work when I tried it. It recognized the audio output as miniDSP, but there was no sound.

2. The link for ASIO4ALL is broken.

3. It is not clear how to get to the JACK menu like that. For example, you have to open up "JACK Control", then press the "Connect" button to get to the page on the screenshot. Also, I see no readable client or writable client in that screen. I don't see how to select ASIO4ALL as my audio interface.

4. How do you aggregate the two audio devices like the screenshot? There is no aggregate button. Plus, on your screenshot it points to Speclab. I'm sure 99% of your users are not using a Speclab as their output.

5. It would be better if the ASIO4ALL screenshot was placed below the JACK screenshot. I spent some time trying to find the ASIO4ALL panel before realizing it only opens through JACK.

Hello all,
Can we be absolutely sure two minidsp 2х4 HD boards connected to agregated USB will have exatly same processing delay?
I guess asyncronius data transfer to each device will add a given delay, and the start of data transmition should not very across two boards.
There is also pll buffer which has some delay.
Quartz generators are quite accurate, but nothing is accurated absolutely, and wouldn't after some time the stream from first board differ to that from the second board?

Dear both

Sorry for missing this post..

@bcodemz
We're not sure why it's not working for you .. i.e. asio4all link fine at time of posting, still fine today, install of jack audio worked fine, USB audio worked on 2x4HD since the beginning. Maybe source wasn't selected correctly in plugin?

- Aggregate on OSx (first google link: support.apple.com/en-us/HT202000)
- Connection screen on Jack: Did you connect your 2x4HD and install ASIO4ALL?

Sure, we could do a 10p app note, we just wanted to help.. Maybe if you have more feedback, send us your method? It's community, we all help each others..

@ AlexanderSokolov,

There would indeed be some latency between the 2 boards as they are async. If the pll buffer latency is your concern (very tiny) then indeed you'd want to use one board does it all (i..e more IO)

HTH

Just in case no one has noticed, Jack Audio for windows download link is dead! jackaudio.org/downloads/ for windows - "File not found".

I have found an alternative link on this site - github.com/jackaudio/jack2/issues/147.

The link is - wahou.net/dl/Jack_v1.9.10_64_setup.exe

This worked on 30/04/2014.

devteam wrote:

Dear All

NOTE: Control will still need to happen one unit at a time. Our plugins not having the ability to TUNE 2 systems together.

Have fun!

DevTeam

And for my next request.....

(seriously, this feature would be amazing if possible)

I found another way to get two 2x4 HD boxes to work in parallel, from a single USB source:

USB source (e.g. PC) --<USB cable>-- MCHStreamer --< Toslink cable #1>-- Toslink Splitter
--<Toslink cable #2>-- miniDSP 2x4 HD #1
--<Toslink cable #3>-- miniDSP 2x4 HD #2



This setup allows both 2x4 HD boxes to receive the same optical data stream from the source, which should minimize any latency between the two boxes. A total of 8 analog outputs (4 from each 2x4 HD) are realized.

A similar setup can of course be achieved using one OpenDRC-DA8, for even less cost. One advantage of the above setup is 96K DSP processing rate, which the OpenDRC-DA8 does not support AFAIK. There is also galvanic isolation through the optical connections. For me, I just happen to have two 2x4 HD boxes and an MCHStreamer around, so this saves me from having to acquire the OpenDRC-DA8 to get the 6 analog outputs I wanted for tri-amplification.

what about USB splitter cable

There is no such thing as a USB splitter cable. There are USB hubs, but plugging 2 miniDSP 2x4 HD boxes through a USB hub will still cause the PC host to see two distinct audio devices, and Windows does not support concurrent streaming of same content to more than one playback endpoint at a time.

The OP talks about using software such as JackAudio and ASIO4All to perform the signal Y-split. I tried this the other day but could not get it to work properly. In contrast, my configuration with the Toslink splitting worked immediately after connecting everything up, with no need to mess around with any software.

One caveat: the 2x4 HD plug-in can support only one box at a time. When I had both boxes attached to USB ports, the plug-in could only work with one of them, so I had to unplug the second box to configure the first, then unplug the first box to configure the second. It would be great if the plug-in, when launched, can allow selection of one of multiple boxes. This can save a lot of USB plugging and unplugging.