How Do I Add a JL Sub to My Current Setup?

[Side Show 10+ year member]

sorry just checked, it only has pass-thru

 

[Jepalan]

OP - you are misunderstanding the HP and LP on your P300-2. A bandpass filter requires a highpass *and* a lowpass filter to be active at the same time. If you want a bandpass that passes frequencies between 80 and 500hz (for example), then you need a highpass adjusted for 80 hz *and* a lowpass adjusted for 500hz.

Your P300-2 has a *single* filter that can either be a highpass (HP), lowpass (LP), or disabled (AP).

When you enable HP mode the amp will put out all freqs from the HP cutoff to 20Khz. When you enable LP it will pass all freqs from approx 20Hz up to the LP cutoff.

You won't hurt your mid woofers running then from 80hz to 500hz, but you might miss out on some freqs above 500hz if they aren't covered by other speakers.

What other speakers are in the car and where are they located and do you know what freqs they are cut off at? Sorry I'm not familiar with that car.

 

[Side Show 10+ year member]

Pics would prob help too

 

[cpthoneybadger]

Site Show- Correct, the amp for the JL has pass-through only. Pictures of what?

When you enable HP mode the amp will put out all freqs from the HP cutoff to 20Khz. When you enable LP it will pass all freqs from approx 20Hz up to the LP cutoff.
You won't hurt your mid woofers running then from 80hz to 500hz, but you might miss out on some freqs above 500hz if they aren't covered by other speakers.

What other speakers are in the car and where are they located and do you know what freqs they are cut off at? Sorry I'm not familiar with that car.

What you're saying is that I'm reading it wrong. The "50-500Hz" spec just means the cutoff range, not necessarily the max range when in HP.

I originally replaced the factory underseat "subs" that were more like mid-bass speakers with the two SWS-8 subs. I had the amp for the SWS-8s set at LP 200Hz.

So what it comes down to then: is there any problem with putting the SWS-8 amp at HP 80Hz? Will that negatively affect anything?

Or is it better to just set both amps at LP and 80Hz for the JL and 200Hz for the SWS-8s? The subs will "blend" at the lower frequencies, up to 80Hz; and the mids will keep going up to 200Hz.

Or is it worth buying the FMOD Inline Crossover 50Hz High Pass and plugging it into the SWS-8 amp?

Thanks for all your help!

 

[Side Show 10+ year member]

the subs wont blend at all, if two different size subs play the same freq at the same time it will sound like crapola.

do you have any tweeters in the car? i'd suggest you do a search on active component speakers

 

[tommydh 10+ year member]

you may want an Audio Control line driver. I have 07 Mini and it was only way to get clean signal til I swapped HU

 

[cpthoneybadger]

****! I guess my best option is the FMOD at HP 50 or 70Hz.

I have a tweeter in each A pillar.

the subs wont blend at all, if two different size subs play the same freq at the same time it will sound like crapola.
do you have any tweeters in the car? i'd suggest you do a search on active component speakers

 

[Side Show 10+ year member]

i'd suggest you go for a active set up, meaning each set of the speakers (eg tweeters, mids & sub) each have there own frequency to play. you may need to upgrade your deck or get a active crossover.

 

[cpthoneybadger]

I have a friend who said I can have his JL 250/1 amp: http://images.sonicelectronix.com/images/148517/big/jl2501.jpg

It has Preamp Output with Full-range, low-pass, and high-pass with the same cutoff as the low-pass frequency selected under Amp LP Filter.

I'm assuming I could set the Amp LP Filter at 12dB, 80Hz and the Preamp Output to High Pass. Then set the current Rockford Fosgate amp for the SWS-8s at 175Hz. That should create a bandpass crossover, right?

The JL playing up to 80Hz and the 2 SWS-8s playing 80-175Hz.

 

[Side Show 10+ year member]

pre amp output to hp 80hz, and lpf on Rockford amp at 175hz... is correct yes. let us no how you like the sound of it. (being your using subwoofers as mid-bass drivers)