RTA - Alternatively if you are really into this, you can buy RTA software
for PC's and with a mike do the testing yourself. www.trueaudio.com has RTA
software 99$ for 32 band rta.

If you know of other software, I'd like to know.

Derek

"Scott Gardner" wrote in message
...
On Wed, 10 Dec 2003 08:36:20 +0200, "Peter"
wrote:

Seriously, it sounds like your deck has some pretty sophisticated EQ
capabilites. Once you get everything installed, why not take it to a
shop that has an RTA and have them tune it up for you? It shouldn't
cost much, and the results are a lot better than tuning "by ear".

Ahem... what is RTA?

Peter


Sorry. RTA stands for "Real Time Analyzer". An example is the
AudioControl SA-3055. It's a 30-band analyzer, meant to be best used
with 30-band equalizers.

Here's how you use it. In your car, you play a disc of "pink
noise", which is nothing more than all frequencies from 20 Hz to 20
kHz, playing at the same time. It's different from "white noise", but
that's not important here.
If your stereo were reproducing the pink noise perfectly, the
30 bands on the RTA would all show the same level, meaning that all
frequencies are being reproduced equally in your stereo.
Unfortunately, your speakers do not reproduce all frequencies
equally, and the shape and size of your car changes the loudness of
some frequencies more than others. Also, most people don't like the
sound of a perfectly flat response curve anyway.
These peaks and dips in your system's response show up on the
RTA screen, and show you exactly what frequencies you need to adjust,
and by how much. This is how you "see" a wide peak that needs a large
"Q" value to correct it, or a small narrow dip that needs a smaller
"Q".

Scott Gardner