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Gear / Technical Help => Post-Processing, Computer / Streaming / Internet Devices & Related Activity => Topic started by: Rerun on November 14, 2015, 08:18:45 AM

Title: Strange Interference during DAT transfer to Computer
Post by: Rerun on November 14, 2015, 08:18:45 AM
Hey Folks,
I was wondering if someone could shed some light on a little problem I have:

I am transferring DATs via a Panasonic SV-3800 > toslink > Editrol UA-1EX > usb > audacity on my macbook as a .FLAC file.

If I listen to the recording from my computer during the transfer, I will sometime hear a little "pat pat pat pat" noise but if I listen to the same recording at the same time from the SV-3800 or from the UA-1ex, I am not hearing the noise.

Something is happening  during the process.  Either the UA-1EX or audacity or my Mac is causing it.  Maybe I should use a different device than the UA-1EX.

Any suggestions?

Any thoughts?
Title: Re: Strange Interference during DAT transfer to Computer
Post by: yousef on November 14, 2015, 09:25:59 AM
I'm not sure if this is relevant to your issue but when I was transferring old DATs a few years ago I found that the audio output from the DAT player seemed to be applying error correction (and therefore sounded fine) whereas the optical output appeared to to be the pure digital stream (ie with errors) and the resulting file had a number of issues.

I rectified this by taking the audio signal rather than the digital. This may well be unacceptable to some people; the gaps and clicks were more unacceptable to me.
Title: Re: Strange Interference during DAT transfer to Computer
Post by: Rerun on November 14, 2015, 09:48:18 AM
Interesting.

But the noises are not present when listened through the edirol ua-1ex.  I believe something is happening from the Ua-1ex to audacity

What method did you use to transfer you tapes?
Title: Re: Strange Interference during DAT transfer to Computer
Post by: yousef on November 14, 2015, 06:33:50 PM
I *think* I originally went Sony stand-alone DAT > optical > Iriver H100 but this led to occasional gaps and clicks so I ultimately used the Sony's stereo outs to an Edirol UA-5 which connected to a laptop via USB.

I think you're right though - this doesn't seem to be your problem. I'd probably be trying a different PC and/or a different DAW, checking the drivers are up to date, killing any background processes that might be clogging things up - all stuff you've probably thought of already...
Title: Re: Strange Interference during DAT transfer to Computer
Post by: Rerun on November 15, 2015, 09:45:53 AM
Does anyone else have any insight into this situation?
Title: Re: Strange Interference during DAT transfer to Computer
Post by: larrysellers on November 15, 2015, 09:53:01 AM
It sounds like it may be something the computer is introducing to the recording. Do you have a stand alone recorder with a digital input that you can use to record straight from the Panasonic dat machine?
Title: Re: Strange Interference during DAT transfer to Computer
Post by: Rerun on November 15, 2015, 10:00:54 AM
What do you mean by a stand alone recorder?

What would that tell us?
Title: Re: Strange Interference during DAT transfer to Computer
Post by: keytohwy on November 15, 2015, 10:14:32 AM
Two things jump out at me.

1)  The Edirol was never a high end device, and while I cannot point to specifics, I would not be surprised if it was introducing issues.

2)  Try a different recording app.  QuickTime is built into every Mac and is fine for recording uncompressed audio.

Also, do the audio anomalies exist *after* the recording is made, or only during recording.  Have you reed moving the files to a different device after recording to see if the issue exists there?
Title: Re: Strange Interference during DAT transfer to Computer
Post by: bombdiggity on November 16, 2015, 09:34:07 AM
Why use Audacity and a computer?   

If you're running it through audio recording components (probably a wise idea) why not just run it into your audio recorder (as someone else also suggested above)? 

I ran DAT transfers out of the component Sony DAT deck through optical cable straight into my R-44 optical input.  Once you've got the wav file on a card it's simple regular processing.  Capturing with a program like Audacity in the middle seems a recipe for problems.

The simpler the better IMO. 

Title: Re: Strange Interference during DAT transfer to Computer
Post by: Gutbucket on November 16, 2015, 10:20:46 AM
bombd- The R-44 doesn't feature optical SPDIF.  Perhaps you meant it's coaxial electrical SPDIF input (via RCA connector)? Or perhaps you were using an optical to electrical SPDIF converter in front of the R-44?

Rerun- the suggestion is to transfer directly from the DAT player to a digital recorder which has a digital input, and then transfer the resulting digital files from the recorder to the computer, instead of recording the digital output stream from the UA-1EX using the computer.  Even if both transfers are ultimately made via USB to the computer, the prior is far more robust as it is simply transferring data files.  The second is recording a real-time data stream to the and is susceptible to timing and buffer errors on the computer USB bus.  Recorders are less likely to have problems with that as they are specifically designed for that purpose, rather than being general purpose machines asked to do this specific task.

To do that, you should be able to use any recorder which features a digital input which is compatible with the DAT player's digital output- so you could use a recorder with an optical input, or if the DAT player you are using also has an electrical coaxial digital out, you can use a recorder which features a coaxial digital input.
Title: Re: Strange Interference during DAT transfer to Computer
Post by: bombdiggity on November 16, 2015, 11:22:11 AM
bombd- The R-44 doesn't feature optical SPDIF.  Perhaps you meant it's coaxial electrical SPDIF input (via RCA connector)? Or perhaps you were using an optical to electrical SPDIF converter in front of the R-44?

Rerun- the suggestion is to transfer directly from the DAT player to a digital recorder which has a digital input, and then transfer the resulting digital files from the recorder to the computer, instead of recording the digital output stream from the UA-1EX using the computer.  Even if both transfers are ultimately made via USB to the computer, the prior is far more robust as it is simply transferring data files.  The second is recording a real-time data stream to the and is susceptible to timing and buffer errors on the computer USB bus.  Recorders are less likely to have problems with that as they are specifically designed for that purpose, rather than being general purpose machines asked to do this specific task.

To do that, you should be able to use any recorder which features a digital input which is compatible with the DAT player's digital output- so you could use a recorder with an optical input, or if the DAT player you are using also has an electrical coaxial digital out, you can use a recorder which features a coaxial digital input.

Thanks as always for your clarity GB... 

Yep coax RCA into the R-44.  So Sony PCM-R500 > cable > R-44.  No devices in between, no reencoding.  That preserves the digital data without intermediary (and I think provides the benefit of the robust error correction functionality of the playback deck).