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Voice Quality

We have seen many posts in the past about Unity's volume level, distortions, etc. After doing some comparisons and trails, I don't think we are dealing with a volume issue, but rather an overall voice quality issue. Perhaps originating from the CiscoTSP itself.<br><br>Perhaps what needs to happen at ActiveVoice (sooner than later hopefully) is to compare their voice quality to that of Cisco's uOne. (Yes, this product is going out the door, but...) I have the two systems running simultaneously in the lab, and the sound quality difference is night and day difference.<br><br>Even after adjusting gain levels on Unity we still experience distortion (even at a low volume) when the volume on the phone is raised.<br><br>Any feedback on this? Is this a TSP issue that is currently being worked on?<br><br>Thanks<br>John.<br><br>

4 REPLIES
Anonymous
N/A

Re: Voice Quality

This is interesting… I’d like to know more about the tests you’re running. I’m wondering if you’re doing a real apples to apples comparison. What Codec are you using on the Unity box? G729a or G711 (MuLaw)? What codec is being used on the uOne? Is it just message recordings that sounds bad or does this include greetings/prompts as well?

I can believe the sound quality will suffer if you’re listening through a device that requires a translation from the native recording format as well… combined with the translations the WAV driver is having to do to adjust record/playback volumes up or down I wouldn’t be overly surprised if the quality was degraded.

I’m a little perplexed about the distortion you’re reporting. This is not the case in house. It sounds like the volume is being adjusted up too much one way or the other or it’s coming in too hot when recording and getting “clipped” to get it under the volume limits set. What really needs to happen is the Cisco WAV driver needs to support true automatic gain control (AGC) instead of having the static raise/lower volumes on record. If I had to guess this is probably where most of the sound quality problem is coming from, but I’d have to see your setup and look at the tests you’re running on to be sure.


Jeff Lindborg
Unity Product Architect
Active Voice
jlindborg@activevoice.com
http://members.home.net/jlindborg

Anonymous
N/A

Re: Voice Quality

To do a fair comparison, I've installed both boxes 'stock'. Both are running on the MCS-7835, G.711
All db levels are stock on both machines as well (for the comparison).

Have you compared the two?
uOne 5.01E
Unity 2.4.5(66)

Thanks
John.

Anonymous
N/A

Re: Voice Quality

I don't have a uOne handy to test against... can you mail one to me ;->

Jeff Lindborg
Unity Product Architect
Active Voice
jlindborg@activevoice.com
http://members.home.net/jlindborg

Anonymous
N/A

Re: Voice Quality

You said you played with the gain levels. What are your settings for "WaveDBGainPlayback" and "WaveDBGainRecord".

FYI,

The WaveDBGainPlayback should be between -10 and 0. If it is set to a value less then -10 then you will hear a fairly big drop in audio quality.
The WaveDBGainRecord should be between 0 and 5. If you set this to more then 5 you will get distortion on the recordings.

Aaron Belcher
Software Engineer
Active Voice
abelcher@activevoice.com

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