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Subject: Re: High kbps/Low kbps power consumption
From: stevem_at_gator.net
Date: 2003-06-06


That was a really informative reply, John. Thank you very much!

Steve

> On Thu, 5 Jun 2003 13:08:28 -0400 (EDT), <stevem_at_gator.net> wrote:
>
>>As a followup to my previous email, I've noticed that my Jukebox
>> recorder 20 has trouble with 320kbps-formatted MP3 music files when the
>> battery level gets down to around 55 percent or less. Is this a known
>> issue with the Jukebox? I didn't see much about it in the bug reporting
>> list.
>>
>>I loaded the daily build ajz from June 4th, but I'm still having this
>> problem. I can hear the hard drive being accessed, then, afer a while,
>> the music will cut in again. It drops out intermittently.
>
> 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.
>>
>>Anyway, seeing this happen is what prompted my previous question. Is it
>> best not to play music on the recorder formatted above 128 kbps?
>
> 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.
>
> 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.
>
> If you're using the thing primarily in non-optimal listening
> environments such as a noisy office, the car, jogging and such, you
> might try going even lower. There is a tradeoff between bit rate and
> battery life. You might find the lower sampling rate adequate for those
> environments.
>
> I downsample my audio books to 32kbps. there is a little distortion but
> it's acceptable, certainly better than, say, a mobile radio. My FM can
> suck in whole chapters at once, spinning the hard drive only every 15-20
> minutes or so. That is how I get better than 14 hours' life out of a
> charge.
>
> 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.
>
> John
>
>>
>>Thanks,
>>
>>Steve
>>
>>
>>> Hi folks.
>>>
>>> I have an Archos recorder 20. Does playing a 320 kbps recording pull
>>> more power from the batteries than playing a 64 kbps recording?
>>>
>>>
>>> Thanks!
>>>
>>>
>>> Steve
>>
>>
>
> ---
> John De Armond
> johngdDONTYOUDARE_at_bellsouth.net
> http://bellsouthpwp.net/j/o/johngd/
> Cleveland, Occupied TN



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