Best Voice Quality Codec?

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Zapo

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What is the best quality codec, I think they refer to them as HD codecs.

I.e. forget how much data it uses, Im running gigabit ethernet between the two phones.
What's gonna be the best sounding codec?

I have tried to do some goggling on this and I keep seeing g722 but as far as I know this is an old school codec.
g729 is more for good compression (ie my sip trunk running on the internet)

My pbx has the following:

ILIBC
AAl2-G.726-32
ADPCM
G.723
H.263
H.263p
PCMU
PCMA
GSM
G.726
G.722
G.729
H.264

And then which one would be best recommended to run my sip trunks on? Using 1meg dedicated dsl line.
 
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Zapo said:
What is the best quality codec, I think they refer to them as HD codecs.

I.e. forget how much data it uses, Im running gigabit ethernet between the two phones.
What's gonna be the best sounding codec?

I have tried to do some goggling on this and I keep seeing g722 but as far as I know this is an old school codec.
g729 is more for good compression (ie my sip trunk running on the internet)

My pbx has the following:

ILIBC
AAl2-G.726-32
ADPCM
G.723
H.263
H.263p
PCMU
PCMA
GSM
G.726
G.722
G.729
H.264
Click to expand...

Im pretty sure thats a video format.
 
Zapo said:
Thanks, I still do appreciate knowing that its the better one out there.

I assume the video ones are for voip phones which do video calling?
Click to expand...

What type of PBX? Some of the codecs are going to become licence free in 2014, so might then be supported

Read here : http://www.techrepublic.com/article...s-without-crippling-your-network-performance/

If bandwidth is not an issue then g711 , also the widest supported

For best sound quality (HD voice), g722.2 (known as AMR-WB*) is recommended, but is not free

http://www.8x8.com/Resources/Learn/HintsandTips/SelectCodec.aspx
 
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There's always the uncompressed option if you want the absolute best.
 
My personal preference is G729 paid for & licensed. Works great for me over DSL into the office :)
 
nkawit said:
My personal preference is G729 paid for & licensed. Works great for me over DSL into the office :)
Click to expand...

I actually am in agreement with this, but the op seems to have discounted this for some reason
 
imranpanji said:
I actually am in agreement with this, but the op seems to have discounted this for some reason
Click to expand...

Over a 1M DSL line .... it may not give the results one intends.

I had staff running it over 384k lines for years, but any heavy browsing at the same time without a properly configured firewall and packet shaping/prioritization it was not very usable.

Over 4M lines for the past few years I've not seen any issues.

We do however use the uncontended (??? is it really) IPC from ECN and dial two PPPOE sessions.
 
For internal use go with:
PCMU (G711 ulaw)
PCMA (G711 alaw)

For use on a internet SIP trunk go with G729.

Here is a nice calc that helps with sizing: http://www.bandcalc.com/

One thing to bear in mind with varying codecs is the transcoding CPU hit on the PBX. Making a call from an extension configured to use G711 over a SIP trunk configured to use G729 means your PBX has to transcode the call. This isn't an issue with small deployments, but can be a factor with large call centres.
 
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I use G722 for calls on the same site, as well as between sites that have fibre connections or wireless links. G729 between everything else.

In my opinion G722 is the most widely supported wideband codec amongst hard and softphones.
On cisco 502/4g/525's (this is what i use) or softphones, its like the person is standing right next to you.

g711, is pretty much the quality you get from telkom PRI/BRI and is quite rubbish in comparison

Also, g722 is (backwards?) compatible with G711.
If one endpoint is using G722 and the other is using G711, the endpoint using G722 will hear better sound quality from the other end but the G711 end will not notice much if any difference.

This is juts my experience after a couple of years of being a voip admin
 
I haven't experimented much with G722, but G711 on it's own is decent quality IMO.

The key differences between G711 and G722 as per wikipedia:
G722 provides improved speech quality due to a wider speech bandwidth of 50–7000 Hz compared to narrowband speech coders like G.711 which in general are optimized for POTS wireline quality of 300–3400 Hz. G.722 sample audio data at a rate of 16 kHz (using 14 bits), double that of traditional telephony interfaces, which results in superior audio quality and clarity.
Click to expand...

Which (as I understand it) implies that if you are have G722 and G711 on the other end as per your example, the call would only be as good as the lowest quality codec which is G711. The PBX will transcode the call from one codec to the other. If G711 only operates in the 300–3400 Hz range you're not going to be able to add the missing 50-299Hz and 3401-7000Hz when it comes out the other side because the G711 codec threw it all away when it encoded the voice stream.
 
Dont worry about the line speed.

The 1 meg line is purely dedicated for the voip trunk. Plus there is prioritization etc in the firewall / router. Im running mikrotik CRS125-24G-1S for the main router.

10Meg dsl for internet browning etc and 1meg purely for SIP / VoIP.

I am more than happy to buy g729 codec. But from my understanding its claim to fame is very good compression with still Ok audio?

I might be mistaken though,

Also if I select 722 I dont really know which version it is implementing?

So from all of the comments its a choice between:

722
729
PCMU

??
 
The codec you use with the SIP provider is going to be determined by
1) What the provider supports
2) The amount of concurrent calls you require vs. how much bandwidth you have
The amount of bandwidth available for calls is going to be limited by the upload of your DSL line, so probably 512kbps
 
The best quality you will get on your dsl , will be G729, as it uses less data on you dsl , the codec is for the VoIP providers, G722 is normally for conference type phones, unless you are use neotel which will use G723 as a standard
 
Agree with the above , Opus is a combined CODEC of SILK and CELT , its adaptive too, its the one CODEC to rule them all .
 
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