> > Maybe you all missed the part where I was complaining about > the $15 mixers so my investment in sound cards must be less > than that, would think that at $300 you should be able to get > a real A/D card that would allow a beat frequency down to DC.
I think you'd have a hard time finding a very high performance A/D card with DC coupling. The high end audio recording market is where it's at for performance, because they have economies of scale. You might be able to get an eval board from Wolfson or TDK or whoever makes these hotstuff ADCs, but by the time you lash em up, and deal with the inevitable clunky interface, you might be better off just finding a used FA66 or something. I see M-audio Delta 44 Pro's for $75-80 on Ebay right now or used for $50 (I also see one for $15, but that's too cheap, so it must be just the manual or something.. ) > > Should I even try with my cheap no name cards ? Sure.. Why not. > > Bruce looks like the M-audio is $179 the specs look great if > almost too good, guess I should save my pennies. > http://www.digitalconnection.com/products/audio/ap192.asp ( > first site goggle turned up, did not look further ) http://www.m-audio.com/ is the mfr website. Well.. The data sheet claims 100+dB SNR, but one might want to see some independent testing. But, in general, this is a plausible and practical level of performance. At this level, pretty subtle stuff like wiring layout and connectors starts to be an issue. The amateur software radio folks have been obsessing about this kind of thing, since the dynamic range of the ADC determines the ultimate performance of the receiver in a mixed signal environment (e.g. A figure of merit for receivers is how strong can a signal 2 kHz away be from the desired signal that's right at the noise floor). The popular design for the receiver is a direct conversion scheme using a 4 way mux driven by a quadrature LO from a DDS, generating an I/Q audio output. > > Assume the one card would be 4 channels they do say multi > card support but with an * and the clock problem would need a > fix not sure I would take the solder to it till the 1 year > warranty is gone but then 4 channels would work. The AP192 is a 2 channel card, but it might have a word clock input or similar. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
