ppi 900.4 lpf not working?

[awholelotofnutz]

Bought the amp about a month ago brand new from sonic electronics and I have been running it on a pair of comps up fronts only using Ch 1 and 2 in full. Finally got my woofers and tweets in and wired up to run active. I used channel 1 and 2 for the tweets set the hpf with the button clicked in to 4000k. Then the woofers on band pass(ch 3,4) with the lp on about 70 to 80 hz, then the high pass with the button clicked in at 4000hz. Turned the radio on and no sound from the woofers. It will work on full but not bpf on the rear channel. I even switched up ch 1,2 and 3,4 still can't get the bpf working. Anyone got any suggestions will be appreciated.

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[wew lad 5,000+ posts]

Bought the amp about a month ago brand new from sonic electronics and I have been running it on a pair of comps up fronts only using Ch 1 and 2 in full. Finally got my woofers and tweets in and wired up to run active. I used channel 1 and 2 for the tweets set the hpf with the button clicked in to 4000k. Then the woofers on band pass(ch 3,4) with the lp on about 70 to 80 hz, then the high pass with the button clicked in at 4000hz. Turned the radio on and no sound from the woofers. It will work on full but not bpf on the rear channel. I even switched up ch 1,2 and 3,4 still can't get the bpf working. Anyone got any suggestions will be appreciated.

do you have the x1/x10 knobs set incorrectly so that you're completely bandpassing the signal down to essentially 0?

edit; yeah you do. run the subwoofer channel with the HPF set 20-30hz and LPF set at 80hz

think about it, HIGH pass filter, LOW pass filter. HPF at 4k for a sub will cut(ok, attenuate for you smarties) ALL frequencies below 4k.

 

[awholelotofnutz]

I have my hu's front and rear rca's Going to the ppi 900.4 for the tweets and mids. My head units rca's is going to my twisted 1.8k. I'm sorry I may not fully understand your reply. ^^

 

[wew lad 5,000+ posts]

I have my hu's front and rear rca's Going to the ppi 900.4 for the tweets and mids. My head units rca's is going to my twisted 1.8k. I'm sorry I may not fully understand your reply. ^^

sorry i was confused, you're trying to bandpass your active midrange drivers. try this, put the filters for your active midranges on HPF only set to 100hz and see if you get output

i think you're using your filters backwards. hpf at 100hz and lpf at 4khz. the other way around and it will cut all signal. the underlying problem is a HPF at 4khz will cut all signal to your speakers below 4khz, a LPF at 100 hz will cut all signal above 100hz, so what signal is left? lol

read this: Electronic Crossover

 

[timhof13 10+ year member]

I agree,I've done this exact same thing. If they work full range, then your filters are probably wrong

 

[awholelotofnutz]

Yep you were right I was running them backwards. I want to make sure I got it right, ch 1 and 2 (tweeters) on hpf set to 4k. Then ch 3 and 4 (mids) set to bpf with lpf at 4k and the and hpf at 100. I know mids are right what about the tweets ch 1 and 2.

 

[timhof13 10+ year member]

Sounds like a good starting point

 

[awholelotofnutz]

^^^ but is the way ch 1 and 2 for the tweets correct hpf at 4k. Also wanted to say thanks for all the help.

 

[CSCStang]

^^^ but is the way ch 1 and 2 for the tweets correct hpf at 4k. Also wanted to say thanks for all the help.

Yes that's correct. You will need to spend some time dialing it all in I'm sure but 4k is good for the tweets.

 

[awholelotofnutz]

Yes that's correct. You will need to spend some time dialing it all in I'm sure but 4k is good for the tweets.

CSCStang is your in pm box full

 

[Papermaker85 5,000+ posts]

what is your placement on the tweeters and the mids? what tweeters and mids you have? did you deaden the doors?i usually like to cross my mids around 2k-2500 and the tweeter around there too.

 

[CSCStang]

CSCStang is your in pm box full

No sir