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Subject: Re: Car Settings
From: Chris Muth (rockbox_at_muth.cc)
Date: 2003-10-10


Alright, you asked for it. :-)

I had this exact same question myself. I knew that using my Sony CD player in my car sounded good, so I figured that
getting my JBR to mimic that would be ideal. The CD player has very few eq options, and they are all off by default.
This lead me to believe that flat eq settings would be the way to go. All that was left was to determine what the optimal
volume setting would be.

I broke out my Digital Domain: A Demonstration CD and put it in the CD player, and played the equivalent MP3 on the JBR.
I used the 1kHz Sine wave test in both the JBR and the Cd player. I hooked my oscilloscope up to the line out of the CD player
and the ear out for the JBR. I used the dual setting on the scope so I could see both sines at the same time. Then I just
tweaked the volume up and down on the JBR until the two sines looked like they had the same amplitude.

As it turns out, Vol = 90% produced the best match.

This is the interesting part. The two sines had slightly different frequencies. I could tell this because I would trigger on A or B,
and B or A would slowly move to the left or right. Though, I didn't count periods to see which was closer to 1kHz. Maybe I will
do this again some time and see.

Regards,
        Chris Muth

On 10/9/03 at 10:58 PM Brian wrote:

>okay, been a while since i've asked a question in this mailing list...
>
>What's your car sound settings?
>I've been having quite a headache trying to figure out the best setup.
>'95 toyota camry:
>
>volume: 90
>bass: 3
>treble: 0
>channels: stereo
>loudness: 13
>bass boost: 10%
>AV decay: 0
>
>I'm trying to get a good setup where:
>a.) delivers same sound as regular radio
>b.) not too much of a volume step-up/down when changing from radio to
>archos
>c.) sounds good at all volumes (that is, the volume i set on the car
>stereo)
>
>Generally, i want the same kind of signal sent from the Archos that a
>normal
>CD player would. And yes, I've tried flat setup... it just sounds too
>flat.
>And i usually end up with something that either chomps the bass or has
>ear-piercing treble.
>
>Thanks.....
>Brian



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