PSW350 Calibration Question

jgido759
jgido759 Posts: 572
edited April 2002 in Technical/Setup
Picked up the S&V Tune-Up Calibration Disk and calibrated my system. Sounds so much better. Now I have a question concerning the calibration of my Polk PSW350. The sub is connected to my Yamaha RX-V595 via a subwoofer cable connected to the "Sub Out" on the receiver and the "LFE IN" on the sub.

Is it "better" to run the subwoofer amp volume control higher (12:00 position) and the A/V receiver sub output signal lower (i.e. -5 instead of 0, receiver range is from -20 to 0) or to run the receiver wide open and adjust with the sub amp? Which will produce the "cleanest" sound?
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Post edited by jgido759 on

Comments

  • Dr. Spec
    Dr. Spec Posts: 3,780
    edited April 2002
    jgido759:

    When you crank up the volume on anything with an amplifier, you are also proportionally cranking up any background hum and noise along with it.

    As a test, simply stick your ear next to the sub with no signal input and max out the volume control. You will hear a noticeable increase in noise and hum.

    This concept is known as the Signal to Noise ratio, or S/N for short.

    The hotter your input signal is to the sub (say 0db or higher), the easier it will be for the sub amplifier to convert that signal to useable sound with a minimum increase in its own inherent noise and hum. This situation would have a high S/N ratio, and that's a good thing.

    Conversely, if you feed your sub a very weak signal (say -20db), it will be harder for the sub amplifier to convert that signal to useable sound, and you will need to crank the volume control on the sub much higher, and the associated increase in noise and hum will be proportionally greater. This situation would have a low S/N ratio, and that's a bad thing.

    As such, I run my receiver sub volume at +1 db, and adjust sub volume at the sub.

    Hope this helps............

    Spec

    ;)
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  • jgido759
    jgido759 Posts: 572
    edited April 2002
    Dr. Spec,

    Thanks for the explanation. That is how I currently have it set up. I just wanted other people's opinions as to how they would calibrate their sub.
    Oh, you hate your job? Why didn't you say so? There's a support
    group for that. It's called EVERYBODY, and they meet at the bar.
    -Drew Carey

    There is a very fine line between "hobby" and "mental illness."
    -Unknown

    My DVD Collection