How to retrieve audio signals from DTR-2602 using labview vi?

[Bhugs]

We have in our possession a DTR-2602 unit, and we have connected it to an audio capturing unit, Edirol UA-5, which has a usb port connecting to a Mac (with OS X). I am not familiar with labview programming and so I was looking for an existing vi that retreives the audio signals from the left and right channels. The information stored on the DTR is as follows,

Each sample of each channel is stored on 16bits. The two last bits are replaced by information corresponding to synchro(s) and the voice channel. On the tape, these bytes are recorded one after the other.

The flow of information coming out of the DIGITAL OUTPUT of the DTR is 192000  bytes per seconds : (2bytes per sample, two main channels, 48 KHz of sampling rate)

The left and right channels on the DTR-2602 unit has 8 input/output ports respectively.

Could someone please suggest where I could find an exiting vi?

Thank you in advance.

[Brian_T]

Bhugs,

Have you checked the example programs built in to LabVIEW?  To access these, go to Help->Find Examples.  You might be able to find a VI you can use directly, or modify to suit your application.  You should probably start with one of the Serial read programs, such as Basic Serial Write and Read.vi.   To use this however, you will need to know the specific command that is needed by the Edirol UA-5 in order for it to return the data you are looking for.  Hope this helps!

Brian T
Applications Engineer

[Bhugs]

Brian, thanks for your input. I will check out the example VIs and see if it works for me. If not, I will get back to you.

[Bhugs]

Brian,
Is there a sample VI which will read .aif files or .wav files? My only concern at this point is to make sure that the 8 output data from the left and right channels respectively are read, and is available for further analysis. So, I would like to know if capturing the audio data from the DTR-2602 as a .wav file preserve the 8 or more (from both the left and right channels) output data, and if there is a particular VI that would help me analyze this?

Thank you again in advance.

[Eriquito]

Hi Bugs,

LabVIEW features a number of VIs for analyzing and manipulating sound files.  Unfortunately, these VIs are only available in the Windows and Linux versions, as they make API calls to the DirectX or OSS libraries (respectively).

Please see the LabVIEW Help for more information on these VIs:

Sound VIs (Windows, Linux)-
http://zone.ni.com/reference/en-XX/help/371361D-01/lvpict/soundvisnew/

If you absolutely must do this development on Mac OS, you may wish to search for 3rd party sound file editing libraries that could be called from LabVIEW, or create your own VIs for analyzing the structure of the wave files (this is a very advanced operation).

[cumber]

Hi Eric,
Could you tell me what would be these 3rd party sound file editing libraries? I used Logic Express (MIDI sequencer and digital audio workstation software) to record the audio and save it as a wav file.

Thank you.

[Eriquito]

Hi cumber,

I wasn't referring to any specific libraries.  But if you search on google/sourceforge/etc, you may be able to find some.  LabVIEW has the ability to interact with external libraries via the Call Library Function node.  You can also read in the file directly using the "Read from Binary.vi" and possibly extract the information you need directly if you know the structure of the data in the file (advanced programming skills required!).