Converting to low res audio for phone system

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Dave
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2012/09/29 11:40:15 (permalink)

Converting to low res audio for phone system

Hello all,
 
I have a client who needs telephone on-hold audio spots (spoken work) delivered to them as follows:
 
mono, 8000Hz sample rate, 64 kbs
 
Can someone recommend a (hopefully free) tool that will convert my 16 bit mono files to this format?
 
Thanks.
Dave

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David Ewer
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    yorolpal
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    Re:Converting to low res audio for phone system 2012/09/29 11:45:57 (permalink)
    We use the DBpoweramp app.  Works for converting most anything to most anything else.  It will even do 12 and 8 bit Ulaw conversions...which many older phone systems still require (even tho they sound like arse).  It's cheap too!

    https://soundcloud.com/doghouse-riley/tracks 
    https://doghouseriley1.bandcamp.com 
    Where you come from is gone...where you thought you were goin to weren't never there...and where you are ain't no good unless you can get away from it.
     
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    Fog
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    Re:Converting to low res audio for phone system 2012/09/29 14:05:20 (permalink)
    http://www.wavosaur.com/

    will probably do it and also has a batch mode

    as well as dbpoweramp / DMC , which rolo already mentioned.


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    Dave
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    Re:Converting to low res audio for phone system 2012/09/29 16:27:40 (permalink)
    Thanks!  I downloaded DBpoweramp, and it seems to do the job.  The 8k mono has a defined knps of 7 rather than 64, but I presume this is no problem.  8k and 7kbps is pretty awful sounding. :-)

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    David Ewer
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    Jeff Evans
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    Re:Converting to low res audio for phone system 2012/09/29 16:53:25 (permalink)
    Hi Dave. I have had a fair bit of experience producing On hold messages a while back. Despite the phone not being a great reproduction medium the idea of delivering a low Fi signal into the phone system is a silly one. Firstly do they want to store a million phone message hence the need for such small files. I would say not.

    It is still better to feed in something that sounds great into the phone system. The resultant sound will still sound better on the phone. I actually supplied wave files at 44.1 16 bit but decent mp3's would also suffice.

    What is important though is setting the EQ of the final mix before it goes into the phone. What I found worked very well was to get a phone from somewhere and rip off the handset. I connected a headphone jack to the ear piece and monitored the mix through the phone while I applied the final EQ. You do need to EQ a bit. eg roll off the bass and adjust the mids etc for a nice clear sound in the handset and it can be done.

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    yorolpal
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    Re:Converting to low res audio for phone system 2012/09/29 23:16:04 (permalink)
    While Jeff is right that sometimes you can force a higher bit resolution onto a given system, etc...he misses a crucial point in vendor/client relations.  Quite often, the client doesn't know 8 bit Ulaw from 24 bit 48khz.  Or anything in between.  And no amount of cajoling, explaining or "training" will change their minds from the simple booklet that came with their phone system which insists that all files being dumped into it are mono 8bit Ulaw files.  So be it.  Don't argue.  Give them what they ask for.  They won't know or care.  And they will come back to you again and again.  And they will not consider you a pedantic horses behind for continually trying to "educate" them.  At least that's been my experience...for over twenty five years now:-)  YMMV.

    https://soundcloud.com/doghouse-riley/tracks 
    https://doghouseriley1.bandcamp.com 
    Where you come from is gone...where you thought you were goin to weren't never there...and where you are ain't no good unless you can get away from it.
     
    SPLAT 64 bit running on a Studio Cat Pro System Win 10 64bit 2.8ghz Core i7 with 24 gigs ram. MOTU Audio Express.
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