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Hey dudes, my amp ( Autotek SM1-1500) has got a subsonic filter, I was wondering where would be a good place to set it.

Im thinking I should go with the freq. response on the subs which is 43-250.
Is that correct??

I was gonna set the subsonic just a bit below the low end cutoff and the low pass crossover a bit below the high end. Is that even close to right??

Tim

Ported Box?

If it's not ported you don't really need the SSF.

Depending on your set-up, I'd cross the subs over at around 80hz.

nope its a sealed box. I figured since the amp had the filter Id use it, but I will turn it off. And I will cross the subs over at around 80 hz.

See what was leading to my confusion was the owners manual for the amp was suggestion the use of the SSF as cutoff on the bottom end and the low pass as a ceiling for the upper end of the spectrum for the subs.

But really this makes more sense to me, because as you said you really just need the SSF on a ported box to help out.

Thanks for the iinsight, Justin

Tim

Glad to be able to help.

on a sealed box if you want to use it just set it around 16Hz. That'll just prevent the amp from wasting power trying to produce frequencies you can't hear, anyway.

Otherwise yeah, just leave it off. The SSF is mainly for ported enclosures, to prevent the sub from unloading below the port's tuned frequency.

As suggested, it all depends on your system design.

Generally speaking, the larger the sub the lower the setting, the following will apply:

Sealed: 20 - 30 Hz.

Ported: 30 - 40 Hz. (in this case really depends on the F3 of the enclosure)

Free-Air: 40 - 50 Hz.

If you can 'tune it by ear,' then whatever sounds best, but the goal is to
keep from over-driving the sub (prevent it from distortion/excess excursion).

Hope that helps.

Rick

Hey dude im of a firm belief that all information helps, especially me. LOL

Tim