| Who uses what Codec? Is there a list out there with as many providers as possible and the codecs they use? To me this is the most important aspect since it determines both the quality of the call and how much bandwidth you need, yet I've been very unsuccessful in finding this information. Thanks for any help. |
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| I have 4MBit down/750Kbit up and I use ULAW and G729 depending on which service I use. |
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1 edit | reply to wiggles4
I don't know of any such list but I see no reason we can't make one. I will try to keep this post updated with the information. Right now I can fill in the following.
Vonage: G.711/G.726/G.729
Broadvox Direct: G.711/G.729 + T.38
Packet8: G.729 (G.711 Fax)
AT&T Callvantage: G.711
Broadvoice: G.711
VoicePulse: G.711/G.726-32/G.726-16
Lingo: G729 + T.38
FWD: G711
Voiceline: ?
Iconnecthere: ?
Quantum Voice: G.711/G.729
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[Edited by request. --kc] |
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| Thanks, nsumner. That actually clears up most of the companies I was unsure about. I thanks to the mods for sticking this. I was a bit disheartened when I saw it fall to the third page after half a day.  |
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 sgarrandInsert Witty Phrase HerePremium
join:2000-04-13
West Brookfield, MA
 ·Charter
| reply to nsumner
said by nsumner:
Quantum Voice: ?
That would be G711u and G729a for QuantumVoice. You can choose and use either in the SPA-2000 config for their service.
Scott
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Visit »whythehell.com, FWD number 48043, QuantumVoice user with an UNLIMITED residential toll free number for $42, »QuantumVoice.com/rates_800.shtml |
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| ok, so where can we find info on wich codec offers the best voice quality ?
Thanks in advance,
Adi |
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sgarrandInsert Witty Phrase HerePremium
join:2000-04-13
West Brookfield, MA Reviews:
·Charter
| Try this site: »www.voip-info.org/wiki-Codecs
There is a lot of information out there about codecs. This thread also mentions more links: »[Primus] What determins GOOD voice quality?
Scott
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Visit »whythehell.com, FWD number 48043, QuantumVoice user with an UNLIMITED residential toll free number for $42, »QuantumVoice.com/rates_800.shtml |
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| reply to wiggles4
Here are some example of voice quality MOS (Mean Opinion Score) scores collected before. G.711 has the best voice quality. However, you need to pay for the price of high bandwidth.
1. PSTN switch: MOS is closed to 4.5
2. G.711 A/M: 4.4 or up
3. G.729: About 4.0
4. G.723: About 3.5
5. G.726: If I remember correctly, depend on its rate, the score is between 3.5 to 4.3. |
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magm58
join:2000-07-12
East Elmhurst, NY | reply to nsumner
nsumner for you info Broadvoice is using the codec G711u |
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| reply to wiggles4
Hmm, I can't go edit my post to add Quantumvoice. I am also looking for confirmation on what Codec Broadvoice is using. I was told a while ago they switched from G.711u to G726-32, can anybody confirm what they are using (okay okay okay I shall send them an e-mail). |
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gtj
join:2001-12-10
Golden, CO | reply to wiggles4
More CODEC info...
»www.voiptalk.us/voip_codecs.shtml
originally from ...
»[Vonage] 90, 50 and 30 "Codecs" |
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| reply to wiggles4
Nothing like the hearing the difference of G.711  I compared the quality of P8 and VP next to each other for a while and kept finding myself picking up the VP line instead of the P8 line. The main difference I found was I didn't find myself "stepping" on the other persons conversation. We didn't get the "go ahead" "go--" "you go ahead" type thing you hear from talking in between two different digital cell phone providers. |
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| reply to wiggles4
mutualphone - g.729 |
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ieee1394Premium
join:2001-08-25
Washington | reply to digiblur
said by digiblur: The main difference I found was I didn't find myself "stepping" on the other persons conversation. We didn't get the "go ahead" "go--" "you go ahead" type thing you hear from talking in between two different digital cell phone providers. It's odd that there hasn't been much discussion about this side effect that can sometimes occur. I think it's related to jitter. While either listener may be hearing great audio quality the fact of the matter is that if there is excessive jitter during the connection (usually caused by latency) then the audio will actually be "played back" (as it were) with enough timing difference that you will start stepping over each other's conversation without knowing it until both parties try to talk at more or less the same time.
The other problem that often comes up is that one person in a conversation is speaking and the other wants to interrupt. But for some reason or another it's like the other party doesn't hear the interrupting party at all. |
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| said by ieee1394: The other problem that often comes up is that one person in a conversation is speaking and the other wants to interrupt. But for some reason or another it's like the other party doesn't hear the interrupting party at all. This can also be due to Voice Activation Detection ("VAD"), which is totally independent of Codec. This is a bandwidth-saving feature that suppresses transmission of the audio signal until it detects sound. It conserves bandwidth, but causes a slight delay in the transmission. |
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| reply to wiggles4
I use the G.711 on a 400/256k connection scored a 4.1 MOS , 4.4 was the best.
»www.testyourvoip.com/details.html?id=HX2FJY
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Broadcasting The Classic Hits 24/7 SauceMaster Radio!!!! |
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Walla
join:2004-02-26
Israel | reply to wiggles4
MSM Netphone uses 711 and 726 - soon to have 729! |
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| reply to wiggles4
maybe these guys can help - »www.downetworks.com |
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 pcmeetOfficial Dta Guru
join:2003-09-15
Montgomery, AL | reply to nsumner
Anyone know what codec sipphone.com uses ? I have the dialup sip phone DUV-1000 uses G.729 and want to see if it will work with sipphone. |
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| reply to wiggles4
Voz Online - G729a
we use this Codec because of ots extreemly low bandwidth usage, we have tested all of the available codecs and have come to the conclusion that the g729a has excellent efficiency |
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