View Full Version : WMA9 2-pass CBR & Multi-pass VBR

12-10-2002, 02:03 PM
WMA9 seems to be a vast improvement (in terms of artifacts) over its predecessors. However, it would be nice to see 2-pass CBR implemented, as it cleans up the sound a bit, especially at low bitrates (<128kbps). The WMA9 encoder by M$ has already implemented this feature.

Also, would it be possible to tweak the wma encoder to allow more passes than 2? In theory, it would be simple, as all the 2nd pass is doing is going over the newly-created wma file (changing quantitization maybe?). Even if all the extra passes do is get rid of the annoying "whistling" artifacts below 128kbps, I would be happy, as wma seems to handle pre-echo better than mp3.

As much as I dislike wma and its nasty artifacts, it is starting to a better choice for portables from 96-112kbps than mp3. However, it still needs some refinement. Are the above suggestions possible to implement in dbpoweramp?

12-10-2002, 03:13 PM
I will put the 2 Pass CBR on my list of things to try, as far as passes are concerned - 2 pass is the max they go to, there is provisions there to go higher but no existing codec uses it.

Edit: Yes CBR 2 pass is suported and accessible, I will add it when a get a free moment.

12-22-2002, 02:39 PM
As i first compared the options of Windows Media Encoder and WMA9 encoding in dMC I realised that there were TWO important things missing in dMC -
1. CBR 2-pass; and
2. Peak Bit-Rate option for VBR encoding
At least I think dMC is currently using Average Bit-Rate setting for VBR encoding so there should also be an option to encode Average Bit-Rate VBR AND Peak Bit-Rate VBR .wma files in dMC.
Anyway if these two options are also gonna be added to dMC I prefer converting to WMA with dMC because it's MUCH simpler and quicker to encode with dMC than with Windows Media Encoder!

01-18-2003, 07:57 PM
Any chance of an update in the near future?

01-19-2003, 06:24 AM
Appologies, I completely overlooked it, I will start it now.

01-19-2003, 09:39 AM
CBR 2 pass released.

01-19-2003, 11:30 AM
WOW! This is GREAT! WMA sounds better than ever at low bitrates. Thanx.