[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: odd sound quality from TDT System 3?

Dear list,

we bought some TDT Sytem 3 modules two years ago (two PA5 and one HB7), using exactly the configuration Volker Hohmann recommended - and in fact it was him who pointed me to the excellent 8 channel AD/DA converter RME ADI/S - thanks Volker!

Now, when I setup the system back then, I always had a clearly audible noise/buzz on one channel. I exchanged *many* emails with the TDT support team, but we didn't find the reason for the noise. Finally, I removed all modules from their rack and then put them back in - and the noise was gone! So it seems that for one of our modules, the PCB connectors TDT use inside their racks had some contact problems, resulting in some high-frequency noise pickup.

For those who want to use Matlab plus AD/DA plus analog signal conditioning:

As for my experiments I need at least two audio channels for stimulus generation *plus* two channels for the generation of visual signals (LEDs marking observation intervals etc.) I spent quite some time looking for a tool capable of multi-channel playback from Matlab and finally found pa_wavplay


which is a Portaudio-based tool that can playback and record on as many channels (simultaneously) as the sound card supports - via an ASIO, MME or WDM driver. Works very stable, although you cannot control the latency between input and output and you cannot use disk streaming. So if anyone knows a tool which also includes the latter two features, please let me know!

All the best


Dr. Daniel Oberfeld-Twistel
Universität Mainz
Institute of Psychology
Experimental Psychology

Staudingerweg 9
55128 Mainz

Phone ++49 (0) 6131 39 22423
Fax   ++49 (0) 6131 39 22480