USB Audio help

I’ve been collecting info on USB Audio devices to check that the work nicely with RO. So far this looks good as most current common examples do. e.g. The very popular ‘3rd Gen’ Focurite works “out of the box” with RO here despite the makers saying it won’t! So I’m happy that pretty much any 2 channel in/out device will work if it follows the USB Audio Class specs.

However, I’m starting this thread to seek some help with testing devices that are more expanded than 2in/2out. In particular, ones that can accept 4 or more in and/or out and may include a digital SPDIF/Toslink amongst them. I know Focusrite make some of these, and they are of interest for many reasons.

So, does anyone here have such a device and also a RO system that included the USB Audio support? If so, could you please try connecting it to the machine and running my ‘Probe’ program which can be found here? :

http://jcgl.orpheusweb.co.uk/temp/USBAudioProbe_rc.zip

This simply runs a series of requests looking for audio ‘pipes’ for input and output. Then lists the details of any it finds reported by the device. Seeing some lists for devices like the Focusrite 8i6 or higher would be very useful. e.g. If I know they work I can then buy one to test more fully and people can write recording/playback/etc software for them.

Note that running the program produces no real output if your machine lacks the USB Audio support, or if you have no suitable device. So if no input or output ports are listed it could be for either reason. However if you have more than one device and a suitable machine+OS all the details of all the devices will be listed.

Thanks,

Jim

USBAudioProbe ver 2.00

List of USB Audio device 'pipes' in order found :
===============================================

INPUT  046d_0990_03_01 0x0008  '' ''


Pipe details:
=========

pipe 0 => Input  (ADC) 
046d_0990_03_01
index           :resolution:channels:bytes: 
 0 rate   16000 :    16    :   1    :  2  :

Done!

USB WebCam

List of USB Audio device ‘pipes’ in order found :
===========

INPUT 08bb_2902_02_11 0×0002 ‘Burr-Brown from TI’ ‘USB Audio CODEC’
INPUT 08bb_2902_02_10 0×0002 ‘Burr-Brown from TI’ ‘USB Audio CODEC’
INPUT 08bb_2902_02_0f 0×0002 ‘Burr-Brown from TI’ ‘USB Audio CODEC’
INPUT 08bb_2902_02_0d 0×0001 ‘Burr-Brown from TI’ ‘USB Audio CODEC’
INPUT 08bb_2902_02_0b 0×0008 ‘Burr-Brown from TI’ ‘USB Audio CODEC’
INPUT 08bb_2902_02_0a 0×0008 ‘Burr-Brown from TI’ ‘USB Audio CODEC’
INPUT 08bb_2902_02_09 0×0008 ‘Burr-Brown from TI’ ‘’
INPUT 08bb_2902_02_08 0×0010 ’Burr-Brown from TI’ ‘USB Audio CODEC’
INPUT 08bb_2902_02_07 0×0010 ‘Burr-Brown from TI’ ‘USB Audio CODEC’
INPUT 08bb_2902_02_06 0×0040 ‘Burr-Brown from TI’ ‘USB Audio CODEC’
INPUT 08bb_2902_02_05 0×0040 ‘Burr-Brown from TI’ ‘USB Audio CODEC’
INPUT 08bb_2902_02_04 0×0080 ‘Burr-Brown from TI’ ‘USB Audio CODEC’
INPUT 08bb_2902_02_03 0×0080 ‘Burr-Brown from TI’ ‘USB Audio CODEC’
INPUT 08bb_2902_02_02 0×0100 ‘Burr-Brown from TI’ ‘USB Audio CODEC’
INPUT 08bb_2902_02_01 0×0100 ‘Burr-Brown from TI’ ‘USB Audio CODEC’
OUTPUT 08bb_2902_01_03 0×01c0 ‘Burr-Brown from TI’ ‘USB Audio CODEC’
OUTPUT 08bb_2902_01_02 0×01c0 ‘Burr-Brown from TI’ ‘USB Audio CODEC’
OUTPUT 08bb_2902_01_01 0×01c0 ‘Burr-Brown from TI’ ‘USB Audio CODEC’

Pipe details:
=====

pipe 0 => Input (ADC)
INPUT 08bb_2902_02_11 Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 11025 : 8 : 2 : 1 :

pipe 1 => Input (ADC)
INPUT 08bb_2902_02_10 Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 11025 : 16 : 1 : 2 :

pipe 2 => Input (ADC)
INPUT 08bb_2902_02_0f Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 11025 : 16 : 2 : 2 :

pipe 3 => Input (ADC)
INPUT 08bb_2902_02_0d Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 8000 : 8 : 2 : 1 :

pipe 4 => Input (ADC)
INPUT 08bb_2902_02_0b Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 16000 : 8 : 2 : 1 :

pipe 5 => Input (ADC)
INPUT 08bb_2902_02_0a Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 16000 : 16 : 1 : 2 :

pipe 6 => Input (ADC)
INPUT 08bb_2902_02_09 Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 16000 : 16 : 2 : 2 :

pipe 7 => Input (ADC)
INPUT 08bb_2902_02_08 Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 22050 : 16 : 1 : 2 :

pipe 8 => Input (ADC)
INPUT 08bb_2902_02_07 Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 22050 : 16 : 2 : 2 :

pipe 9 => Input (ADC)
INPUT 08bb_2902_02_06 Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 32000 : 16 : 1 : 2 :

pipe 10 => Input (ADC)
INPUT 08bb_2902_02_05 Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 32000 : 16 : 2 : 2 :

pipe 11 => Input (ADC)
INPUT 08bb_2902_02_04 Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 44100 : 16 : 1 : 2 :

pipe 12 => Input (ADC)
INPUT 08bb_2902_02_03 Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 44100 : 16 : 2 : 2 :

pipe 13 => Input (ADC)
INPUT 08bb_2902_02_02 Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 48000 : 16 : 1 : 2 :

pipe 14 => Input (ADC)
INPUT 08bb_2902_02_01 Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 48000 : 16 : 2 : 2 :

pipe 15 => Output (DAC)
OUTPUT 08bb_2902_01_03 Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 32000 : 8 : 2 : 1 :
1 rate 44100 : 8 : 2 : 1 :
2 rate 48000 : 8 : 2 : 1 :

pipe 16 => Output (DAC)
OUTPUT 08bb_2902_01_02 Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 32000 : 16 : 1 : 2 :
1 rate 44100 : 16 : 1 : 2 :
2 rate 48000 : 16 : 1 : 2 :

pipe 17 => Output (DAC)
OUTPUT 08bb_2902_01_01 Burr-Brown from TI USB Audio CODEC
index :resolution:channels:bytes:
0 rate 32000 : 16 : 2 : 2 :
1 rate 44100 : 16 : 2 : 2 :
2 rate 48000 : 16 : 2 : 2 :

Done!

Andrew: The webcam is interesting as it only runs 16k rate. I’d assumed a webcam mic would do 48k as this is the ‘standard’ rate for computers in general. Means it only has an 8k audio bandwidth. OK for speech, though.

Philip: Looks to me like you have a UCA202 or a clone of one. :-) They are strange in using what I’ve dubbed a “Victorian Smoker” approach – i.e. a “Pipe for every occasion!” :-)

FWIW Here is a list of the examples I have scanned thus far. Plan to do a new list at some point and extend it.

http://jcgl.orpheusweb.co.uk/temp/USBATable.pdf

Thanks.

Andrew: What is the make / model of your webcam?

Logitech QuickCam Pro 9000

It’s good to know that the Focusrite 2i2 works with RISC OS. I had considered one a couple of years ago, but I’d been put off by reviews suggesting latency issues around using it with a guitar. Thanks.

FWIW The 3rd Gen 2i2 delivers about a 90dB SNR and THD below 0.003%. (Noise unweighted and for 48k rate bandwidth.) This is via the ‘line’ input as I don’t have a balanced ‘fake mic’ source to check that. But it looks pretty good.

The buttons for line/instrument and monitor also work. I guess the ‘air’ does as well but I don’t have a way to check except to find an old mic and see what it does to the noise floor.

I’m happy to use it for measurement purposes, but it should easily make CD quality recordings if used with care.

I suspect their larger units like the 8i6 may also work fine. But Focusrite simply seem to have a standard “Windows Only and use our Software” mantra. So I’ll only find out if/when someone runs my Probe on one. TBH my interest there is in the possibility of taking in spdif and getting it into my RO machines via USB. That would be really handy – particularly if it works at 192k!