Got an Alpine HU fitted now ( )

The LPF presumably sets the freq. that is sent to the Sub

Whats the HPF do??

Also is the built in crossover just for the Sub?

Do all component speakers have their own crossovers? and is it preferable to use these to the HU crossover?

Jono

Jono,

What HU have you got? I assume the LPF will do the "sub" frequencies and the HPF will do the rest - i.e mid to high - can you dial in different frequencies on the HU?

AS for the squeakers, all components should have some king of crossover, but the cheaper ones tend to be pretty basic - something like Infinity Kappas have two choices for the high frequecies sent to the tweeter.And of course a chuffing great crossover box to stuff somewhere you haven't got space...

Better to use the crossovers with the speakers - even if you send just the "high" frequency signal to them, the crossover will split it down further, to "mid" and "high". Are you following this? :confused:

At the other end of the scale, get seperate amps for sub, kid and tweets and set the crossover on each.

I was just trying to think that I should all frequencies etc, is set by the amplifier, but then as far as I can tell yours runs straight off the HU? :confused: I didn't know that was possible

I was told I would definitely need an amp to power my sub, but there is still a degree of control from the H.U (via the RCA cable), and the crossover card in the back of the amp is what controls whether I want it on low-pass or high pass or mid-range. I actually don't know what it's set to at the moment, but it sounds just fine to me. :speaker:

Got an Alpine HU fitted now ( )

The LPF presumably sets the freq. that is sent to the Sub

Whats the HPF do??

Also is the built in crossover just for the Sub?

Do all component speakers have their own crossovers? and is it preferable to use these to the HU crossover?

Jono

A low pass filter is used to only allow low frequencies through to a sub. Depending on the size and performance of the sub and your other speakers you set the frequency according to how it sounds best.

A high pass filter is used to remove all the really deep bass from the signal sent to the rest of your speakers. The reasoning being that they won't be able to handle the really low stuff and will distort , so if you have the HPF on you can drive them harder.

On my Sony HU I have both set to 78hz and it makes a world of difference to the sound as both sets of speakers can do what they are best at.

Thanks Dr, Z, just what I was trying to say! :cheers:

As I uderstand it, the low pass will only work with an external amp. So as Jason says, the easiest (cheapest) way is to run the LPF (is labelled sub?) via RCA to an amp to run the sub, the other speakers can be run off the internal amp, in which case, just use the supplied crossovers with the components.

I've got an Alpine 7842, which has 3 pre-outs (front rear and non-fading sub) that run to two amps - a 2 channel for the rears and a more powerful 4 channel for the fronts and sub - the benefit of that being the other speakers get a chance too keep up with the sub! :speaker: