amp question

[mikek 0]

hey guys, i have a jbl amp and on it there is a 2 screws, one of them is bass boost and it goes from 0-12 db, the other is a xover frequency and it goes from 32hz to some high number i cant remember right now, what should those be at?

its on a 15" 9500

[Juslivin 1]

personal preference

[mikek 0]

what do they change/do?

[johnecon2001 82]

Bass boost typically should be on zero as it can induce clipping that can kill your speaker if you don't use it carefully.

Your crossover should be set around 80hz.

[mikek 0]

whats clipping? and how can i tell if mine is?

and should the bass boost be set as high as possible without clipping?

[mikek 0]

just looked at the amp and theres a input setting too, how does that work and where should it be?

[KU40 173]

the input setting is your gain. Match it to the RCA voltage coming from the head unit.

Bass boost will just boost a small frequency range, so it will give a hump in frequency response. That doesn't sound good.

[holley2346 6]

But if you are running on a stock hu and using a lo converter and can not control the sub setting you must use bass boost... use it wisely. Although some subs can be tortured and still work for a while it is NOT good for them and will likely kill them as they will be producing a lot of heat....

Rule of thumb keep bass boost on 0... when subs are clipped badly there will be an audible difference in sound, but you shouldn't check for clipping by ear.

[Adrian_D 520]

Bass boost does not replace the sub level control on the head unit, it's just a boost centered around 40-45hz.

[KU40 173]

But if you are running on a stock hu and using a lo converter and can not control the sub setting you must use bass boost... use it wisely. Although some subs can be tortured and still work for a while it is NOT good for them and will likely kill them as they will be producing a lot of heat....

Rule of thumb keep bass boost on 0... when subs are clipped badly there will be an audible difference in sound, but you shouldn't check for clipping by ear.

What do you mean cannot control the sub setting with an LOC? The gain on the amp still works when using that signal.

But bass boost is ok to use if you have a dip in frequency response that you want to even out with the rest of the frequency response. Unfortunately, as John said, the frequency the amp presets the boost for is around 45 hz, which basically no sub box should ever create a dip in response at 45 hz.