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View Full Version : MP3 quality poor due to low volume levels, notcompression.



Rob Studdert
2004-01-02, 08:07
On 2 Jan 2004 at 8:17, T wrote:

> Well, as I previously stated, there is NO clipping introduced (verified by
> various measuring equipment), despite the fact that mp3gain claims there is. If
> it can't be measured, it's not there. And, if the equipment is designed
> correctly (and I've been doing it for 5+ years), a 0dBFS (or any other level
> signal) will exit the decoder at exactly that level with no clipping.

Of course nothing exits the digital I/O at greater than 0dBr, it's the
calculated dynamic overshoot that's clipped.

> Actually, the ARE designed to accomodate the 'technicians top forty', as
> that is what they are primarily used for in the professional world (i.e.
> program distribution from studio to transmitting station).

I've only been in the game for 20 years and freq runs/test tones are oft
referred to as "the techs top forty", not real world dynamic audio.

Rob

Enno Davids
2004-01-04, 18:09
On Sun, Jan 04, 2004 at 10:53:40PM -0000, Simon Turner wrote:
|....
|
|Testing:
|I tried three different integrated amplifiers, a Nad, a very old Trio and a
|Harman Kardon. The results were the same on all so I've not differentiated
|below. I used a Harman Karden CD Player as reference.
|
|I used a CD of a couple of particularly kick drum driven techno songs.
|I ripped these songs to MP3 and made copies of them, adjusting their volume
|levels in MP3Gain (in steps of 1.5db). I then played these back via the
|Squeezebox and the iPod to see how the volume levels compared with the
|original CD.
|
|The original file did not register as clipping by MP3Gain. An adjustment of
|1.5db introduced clipping
|To achieve the same volume level as that produced by the CD player I had to
|adjust the volume level of the files:
|iPod: +4.5db
|Squeezebox: +6db.
|

Is it just me or does this sound like some sort of impedance mismatch
amongst the various pieces of equipment?


Enno.