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Subject: Re: High kbps/Low kbps power consumption
From: Jon Drukman (jsd_at_cluttered.com)
Date: 2003-06-06


At 02:37 PM 6/5/2003, Neon John wrote:
>No, not a bug. Just an effect of running the thing at the edge of its
>performance envelope. Contemplate how much data the thing has to move to
>handle that bitrate and how much processing it takes and how much power that
>requires. Given that there is a fixed amount of RAM, the higher the bitrate
>the more often the drive runs. More power required. You're simply
>overwhelming the unit and with no material gain in sound quality.

no offense, but that's a load of rich creamery butter. my JBR is happily
playing 320K mp3's right now with only 30% battery life left. not a skip
to be heard in 80 minutes (so far) of playing.

>I have very good ears and I can't hear the difference between the original CD
>and 192kbps even on my mid-level home system playing directly from the
>computer. I certainly can't hear the difference once the sound goes through
>the Archos' audio output circuit and then through headphones, even my
>PortaPros. It is a waste of space and processing power to put anything above
>128kbps on the Archos, unless perhaps you're using the digital out to a high
>end system.

now this is a totally different issue. i agree in principle that 192K is
generally OK for most things and that 320K is generally overkill. however
i have found a few pieces where i can definitely hear artifacts at
192K. not many.

in fact this is why i recommend using LAME's "--preset standard" mode. it
averages 192K anyway, and the sound quality is superb. it can "burst" up
to 320K if needed. the only drawback is it is significantly slower to
encode a file than using 192K CBR.

>I store all my rips at 192kbps on my computer. I downsample to 128kbps for
>the Archos using CDex and LAME. On this 2 gig machine the process is quite
>rapid. Since I have the disc space I simply maintain two file trees, one for
>the original rips and one for the archos.

i hope you are not transcoding the 192K files to 128K files but rather
generating the 128's from the original wav or cd.

>Best thing to do is simply experiment some. Downsample to various rates and
>do some listening tests. When you find something you like, check the battery
>life. You'll be pleasantly surprised.

agreed.

-jsd-



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