asteriskusers at dovid.net
2014-Oct-14 15:47 UTC
[asterisk-users] Issue playing high quality white noise
Hi, I have a client that wants a phone system that will play sounds from a sleep machine. I tried using all different formats (GSM, WAV, WV49, MP3 etc.). Over SIP it was OK however with the PSTN it broke up from time to time. I assume this has to do with the fact that the PSTN is limited to 8khz. Is there something I am missing here or is this simply a limitation of the PSTN? Regards, Dovid
Scott Griepentrog
2014-Oct-14 15:57 UTC
[asterisk-users] Issue playing high quality white noise
The limitation of 8khz sample rate (ulaw or alaw on pstn) should only affect the audio spectrum - for example there will be a loss of frequencies above 3.3-4khz if the band pass filter is done correctly, or an overly loud static sound where higher frequencies were in the original if not. If by 'broken up' you mean to say that there are periods of no audio, then there is a separate issue affecting the audio stream such as packet loss or problems getting the audio file to stream reliably. On Tue, Oct 14, 2014 at 10:47 AM, <asteriskusers at dovid.net> wrote:> > Hi, > > I have a client that wants a phone system that will play sounds from a > sleep machine. I tried using all different formats (GSM, WAV, WV49, MP3 > etc.). Over SIP it was OK however with the PSTN it broke up from time to > time. I assume this has to do with the fact that the PSTN is limited to > 8khz. Is there something I am missing here or is this simply a limitation > of the PSTN? > > Regards, > > Dovid > > > > -- > _____________________________________________________________________ > -- Bandwidth and Colocation Provided by http://www.api-digital.com -- > New to Asterisk? Join us for a live introductory webinar every Thurs: > http://www.asterisk.org/hello > > asterisk-users mailing list > To UNSUBSCRIBE or update options visit: > http://lists.digium.com/mailman/listinfo/asterisk-users >-- [image: Digium logo] Scott Griepentrog Digium, Inc ? Software Developer 445 Jan Davis Drive NW ? Huntsville, AL 35806 ? US direct/fax: +1 256 428 6239 ? mobile: +1 256 580 6090 Check us out at: http://digium.com ? http://asterisk.org -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.digium.com/pipermail/asterisk-users/attachments/20141014/c65eeb5d/attachment.html>