Bitrate/Quality Problem [Archive]

raygunray

Jun 8th, 2008, 10:51 AM

WyethDigital

Jun 8th, 2008, 07:25 PM

A reviewer noticed that my shows bitrate was too high and reccomened lowering it between 64-96kbps. I have done this and the quality has suffered. My voice has a metallic, 'speaking into a coffee can' artifact and I don't know how to fix it.

I have listened to podcasts at 64kbps that sound great. Mine doesn't. You may listen to the current, unpublished show for a sample: http://diabeticincandyland.com/podcasts/dic-17.mp3

Here are the Audcacity settings I use to record and encode:
Channels: 1 mono
Sample Rate: 44100
Default Sample Format: 32 bit float
Bit rate: 96kbps

Am I missing something?

Your problem isn't the 96 kbps, it's what the 32 bit float is doing to you. You're wasting file space, and Audacity is filling in info that isn't there. That's why the funky sound.

In your preferences pane for Audacity, set the Default Sample Format to 16-Bit (that's essentially CD quality), and the Default Sample Rate to 44.100 kHz (still CD quality parameters). Then, when you export to mp3, click the options button and set the Bit Rate mode to Constant and set the Quality to 64 kbps. This should get some decent sound without killing your users with huge file size, though with a mono file, you could even go down to an 8-Bit Sample Format, and a 22.100 Quality setting and have a decent sounding recording.

I would also point out that you're compressing a file. That in and of itself will cause a drop in quality from the original recording. Nothing you can do about that, but find a high quality compressor.

Eric