On 11 May 2012 10:37, Ed W <li...@wildgooses.com> wrote: > Beware that the AC97 codec (ie any internal sound card from a few years > back or older) almost exclusively runs at 48Khz and will only work > reliably at that rate. To convert to any other frequency there will > usually be an absolutely awful resampler implementation which will cause > all kinds of wierd (nonlinear) artifacts. As such for anything > requiring even reasonable fidelity and a built-in soundcard, first check > the specs, but then if in doubt run at 48Khz and use your own resampler > to get the frequency you want.
Hi Ed, The actual sound card I use for radio use is the "Startech 7.1 USB audio". It's fairly cheap and cheerful, but not the most cheapest and cheerful. I have also a Soundblaster Audigy PCI card. But, it's not practical to hook it up to the radio (the 3.5m cables are too short). The USB solution is just a general easy solution for me. I have the CI-V, and PTT controllers as USB (prolific controllers) and the sound as a USB card, all plugged into one USB hub. So I can then just present one USB cable to my PC and everything springs into life. I'll go to 48k using the highest quality mode in cooledit and hopefully that's be the safest route to take. > Sox some many years back had a mediocre resampler, but as of some (quite > a few now?) years it's implementation is top notch. There are plenty of > decent off the shelf resampler libraries if you don't want to write your > own code - I quite like libsrc (secret rabbit code..) Sox will be great if I get windows binaries working and I want to work real time. record > codec2 > fdmdv > sox > play > radio. Not sure how that will work in real world terms either. :) ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Freetel-codec2 mailing list Freetel-codec2@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freetel-codec2
