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Subject: Re: crackle in mp3's regardless of bps?

Re: crackle in mp3's regardless of bps?

From: BlueChip <cs_bluechip_at_webtribe.net>
Date: 2005-02-16

> Hello
>
> Is there anyone else that has a problem with high end sound breakdown
> on some MP3's? I get a small amount of distortion on some MP3's that
> sound simial to a pre-amp being turned up to high. It seems to be pretty
> random, and doesnt seem to be confined to any low or high bit
> rate. Might there be something wrong with my V2, or is it just a
> characteristic of mp3's that my ears have just come to hear?
>
>Let me know
>
>Gary

Could well be the mp3's ...but if your settings are tweaked out-of-spec
(which is allowed by Rockbox (which is a good thing)) then you may be
introducing digital distortion.

Flatten everything (treble/bass/etc); disable MDB; and set the volume to
0db (iirc this is about 92 under Rockbox - it is "0db" or exactly "88" with
the audio3587 extension)
This is the maximum you are allowed before introducing digital distortion -
if you then increase the treble by 1db, you must reduce the volume 1db
...if you decrease *ALL* settings by 1db, then you may increase the volume
by 1db ...Audio3587 makes this simple, and flashes the icons when you are
at risk of digital clipping - so whether or not you want to use Audio3587
permanently is up to you, but it would certainly be a good test-bed for
this type of complaint.

BC

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Received on Wed Feb 16 21:41:31 2005


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