Going active questions

[JoshC 10+ year member]

Im in the middle of changing my front stage to active via a sq 4-90. Although i have a question for the final setup.

From what ive been told thus far, i want my high amp to be in bandpass mode for active. The 4-90 settings say LP/BP, so low pass is bandpass? Im very confused on this, i thought the HU was going to control all crossover points. When i did some google searching i found the guys on DYI audio saying when running active the amp should be in full pass mode, so which is it?

HU is a 80prs, ive got the right doors passive xover pulled and am about to pull the lefts. Going to finish this up tonight and see if the sound is any better.

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[big scott]

you can do either.

if you use the h/u crossovers put amp on full.

highs get = hp

mids get = bp

i do like the sq amps crossovers.

nice wide range.

 

[big scott]

before i got the 80prs i was using the crossovers on my amps.

setting up the 80prs i put my amps on full and have all my crossovers on the h/u .

like i said you want...

highs = high pass

midbass = band pass ( that way you set the high and low for that speaker )

mid range = same ^^

on my system..

highs 3k and up

mid-bass 60hz to 250hz

mid range 250hz to 3k

bass 20 to 60hz.

but as you can see im running a true 3-way front stage.

that just gives you an idea.

 

[JoshC 10+ year member]

you can do either.if you use the h/u crossovers put amp on full.

highs get = hp

mids get = bp

i do like the sq amps crossovers.

nice wide range.

Okay, so i do want to use full pass if i want to control all crossovers at the HU. So in full pass will i still see the -24db slope the amp uses or will is see whatever my HU sets it too?

 

[big scott]

yes set to full.

you set it at h/u .

as it looks like when in full there's no set slope.

as the manual says slope in high , bp , lp .

 

[JoshC 10+ year member]

yes set to full.you set it at h/u .

as it looks like when in full there's no set slope.

as the manual says slope in high , bp , lp .

Okay i got everything changed over and reset it, just turned my gains basically to nothing for this test.

Set the unit to

Sub:

80Hz -24db

For mids.

Hpf 125hz, lpf 4kHz -18db

Tweets

Hpf 4kHz -12db

Still in the parking lot so i couldnt actually turn it up, but hopefully it will sound good tomorrow. Although i had an issue getting my right tweeter to work, then it played fine but i noticed my balance is all messed up. If i fade to the left the right tweeter is silent as it should be, but if i fade right my left tweeter is still playing just at a lower volume.

I have left tweet at ch1 and right at ch2, left mid at ch3 and right at ch4. Could i have mixed up the RCAs behind the HU so its getting confused? Like its matching right woofer to left tweeter or something.

Really digging all the different options i get to play with, next step is to make the doors truely dampened and sealed off.

 

[wew lad 5,000+ posts]

Okay i got everything changed over and reset it, just turned my gains basically to nothing for this test.
Set the unit to

Sub:

80Hz -24db

For mids.

Hpf 125hz, lpf 4kHz -18db

Tweets

Hpf 4kHz -12db

Still in the parking lot so i couldnt actually turn it up, but hopefully it will sound good tomorrow. Although i had an issue getting my right tweeter to work, then it played fine but i noticed my balance is all messed up. If i fade to the left the right tweeter is silent as it should be, but if i fade right my left tweeter is still playing just at a lower volume.

I have left tweet at ch1 and right at ch2, left mid at ch3 and right at ch4. Could i have mixed up the RCAs behind the HU so its getting confused? Like its matching right woofer to left tweeter or something.

Really digging all the different options i get to play with, next step is to make the doors truely dampened and sealed off.

i would definitely verify your rca's, i've crossed them before myself. fortunately the front and rear in my set up output the same full range signal highpassed at 80hz, but in your situation you could end up sending the midrange RCA output to your tweeter, it's a little more important lol

not sure if this was clarified or not, in the OP you seemed a bit confused about bandpass, lowpass, highpass, and how full range is necessary at your amplifier if using HU crossovers.

bandpass is a combination of high pass and low pass

the rca outs for your tweeters will need only a hpf

rca outs for your midrange will need a bpf

rca outs for your sub will need a bpf. you said 80hz 24db, is this a LPF? you'll need a HPF as well (i.e. subsonic - a HPF for extremely low frequencies below your box tuning)

you'll leave the amp on full pass due to your control being done at the headunit.

 

[JoshC 10+ year member]

How do I go about setting the tweeters gain? Guessing like a 5khz tone?

 

[big scott]

i played a 3k tone throw my tablet and turned the crossover until it started getting lower in sound.

but play what your crossover to. if you want 5k then do a 5k tone.

it works good doing that.

or if you want exact get a SMD Crossover Calibrator CC-1

 

[big scott]

Okay i got everything changed over and reset it, just turned my gains basically to nothing for this test.
Set the unit to

Sub:

80Hz -24db

For mids.

Hpf 125hz, lpf 4kHz -18db

Tweets

Hpf 4kHz -12db

Still in the parking lot so i couldnt actually turn it up, but hopefully it will sound good tomorrow. Although i had an issue getting my right tweeter to work, then it played fine but i noticed my balance is all messed up. If i fade to the left the right tweeter is silent as it should be, but if i fade right my left tweeter is still playing just at a lower volume.

I have left tweet at ch1 and right at ch2, left mid at ch3 and right at ch4. Could i have mixed up the RCAs behind the HU so its getting confused? Like its matching right woofer to left tweeter or something.

Really digging all the different options i get to play with, next step is to make the doors truely dampened and sealed off.

sounds like your rca are on the wrong ch.

switch them.

if not make sure the h/u is setup right.

but looking good.

 

[wew lad 5,000+ posts]

use a 0db tone at 5khz or anything above your crossover frequency to set your gain

 

[big scott]

i would definitely verify your rca's, i've crossed them before myself. fortunately the front and rear in my set up output the same full range signal highpassed at 80hz, but in your situation you could end up sending the midrange RCA output to your tweeter, it's a little more important lol
not sure if this was clarified or not, in the OP you seemed a bit confused about bandpass, lowpass, highpass, and how full range is necessary at your amplifier if using HU crossovers.

bandpass is a combination of high pass and low pass

the rca outs for your tweeters will need only a hpf

rca outs for your midrange will need a bpf

rca outs for your sub will need a bpf. you said 80hz 24db, is this a LPF? you'll need a HPF as well (i.e. subsonic - a HPF for extremely low frequencies below your box tuning)

you'll leave the amp on full pass due to your control being done at the headunit.

good point.

but on sub output you only get lp.

so on your sub amp you need to set subsonic filter.

 

[big scott]

and when you get the doors done, it will make a big difference.

i have so much work into my doors..

and there about 150 heavier each...

 

[wew lad 5,000+ posts]

and when you get the doors done, it will make a big difference. i have so much work into my doors..

and there about 150 heavier each...

150 pounds? uhh