Anybody notice Pioneer HU's LPF slope cant be turned off

[suleman36 10+ year member]

I have the 780mp and havent really found the menu to set my LPF to off.

 

[nVRuckus 5,000+ posts]

on mine the one to set it to up(right) and down(left) if you push the button in on the remote it turns it off.

 

[frankiebones 10+ year member]

I have the 780mp and havent really found the menu to set my LPF to off.

i have the 7800 so we're in the same boat. i'm gonna call pioneer's support line and see if there's a way on the 780 or 7800.

i'd like to further point out that BASSMEKANIK is a tool by noting that a search of the deh-p7800mp manual (in pdf format) for the word 'full,' as in 'set your pre-outs to full' returns zero results.

it must **** to go out on a limb using 48 pt font, taking pictures of his HU, and scanning parts of his own user's manual to paste on his response only to find out he's wrong.

this is especially the case given that, for an encore, BASSMEKANIK showed us all what a valuable part of these forums he is by stating: "guess noobs cant read either"

the point is this: there are stupid questions, and this wasn't one of 'em.

 

[frankiebones 10+ year member]

i just spoke to someone at pioneer with 25 years of experience as an installer and he told me with 100% certainty that on the 7800, there is no way to turn of the LPF.

 

[suleman36 10+ year member]

I cant believe they put so many useless features on a HU and put hpf on every preout but dont give you the option to set the LPF to pass. This is a big problem considering most amps have built in crossovers already.

I guess im going to sell my 780 and find me a better HU with this feature.

Frankie, me and you have a similar setup.

I have a jl 12w6v2 and a 500/1

 

[ultimate157 5,000+ posts]

So, you guys never answered my question ... are you using your other two pre outs?

 

[frankiebones 10+ year member]

So, you guys never answered my question ... are you using your other two pre outs?

i'm not using my rear output. i assume ur asking bc i could set the rear HPF to pass thru, and then x-over the sub on the sub amp itself.

however, and i am totally unclear on this, but wouldnt that send the sub amp the entire frequency spectrum and make it less efficient? or does it still just have to worry about the frequencies it actually has to produce after being cutoff ?

i know a tech rep at morel told me that by crossing over my front HPF at the HU, so the signal sent to the amp was only 80Hz and up, would make the amp much more efficient since its the low freq stuff that takes the most power....

i am half right or totally wrong?

 

[frankiebones 10+ year member]

I cant believe they put so many useless features on a HU and put hpf on every preout but dont give you the option to set the LPF to pass. This is a big problem considering most amps have built in crossovers already.
I guess im going to sell my 780 and find me a better HU with this feature.

Frankie, me and you have a similar setup.

I have a jl 12w6v2 and a 500/1

this entire time, i have had BOTH the LPF on the HU AND the amp set to 80 Hz. The guy told me this is gonna create all sorts of phase shift problems.

i am gonna go out to my car when i am done studying for law finals (so that should be in a few weeks) and turn the x-over on the JL amp off.

i admit that despite reading a few articles on it, i am not entirely clear on the concept of phase and phase shift. the subwoofer controls on the 7800 have a phase shift control where the sub points down or up, i have mine pointing down bc it sounds better than pointing up, but i dont yet comprehend that sh*t.

i can find a loophole in the federal rules of evidence to allow comments made out of court to be admitted despite serious obstacles, but i cant understand at least 5 of the articles on bcae1

 

[suleman36 10+ year member]

I tried setting the the lpf on the JL amp to off but didnt like the way it sounded. So i changed it back to 12db @ 80hz on the amp and it sounded better. I even tried it at 24db @ 80hz but it brought more distortion. Probably because of the HU LPF being on aswell more then likely.

I have a Alpine 9813 which the lpf and the hpf all are passable aka set to off. I guess ill have to sacrifice the 24 bit burr brown dac for the alpines other option or find me a Pioneer HU that is as nice as my 780 with that option of setting the LPF to off. I really love the 16 band EQ on the pioneer and the 24 bit burr brown dac which sound amazing but with the LPF crossover situation im not so sure about it.

What do you guys suggest ?

 

[ultimate157 5,000+ posts]

i'm not using my rear output. i assume ur asking bc i could set the rear HPF to pass thru, and then x-over the sub on the sub amp itself.
however, and i am totally unclear on this, but wouldnt that send the sub amp the entire frequency spectrum and make it less efficient? or does it still just have to worry about the frequencies it actually has to produce after being cutoff ?

i know a tech rep at morel told me that by crossing over my front HPF at the HU, so the signal sent to the amp was only 80Hz and up, would make the amp much more efficient since its the low freq stuff that takes the most power....

i am half right or totally wrong?

I'm pretty sure that the crossovers do their job before amplification, because from an engineering standpoint on a amplifier, it would be so ridiculously inefficient to amplify then crossover.

Not to mention that the crossover in an amplifier would have to be VERY beafy to handle an amplified signal vs an 2v - 8v input signal.

 

[suleman36 10+ year member]

actually not true.

people are so misled by media hype and advertising about DACs.

a "24 bit" DAC is actually 16 bits to be accurate, with 8 bits overlap. The original source material is only 16 bits as well.

You can't hear teh difference between a 24 bit DAC and a 1 bit DAC in a car anyway. You can't even hear 1% distortion from amplifiers in a car, and the speakers will produce more than the amplifiers will at that.

There comes a point when you need to pay more attention to reality than what's on paper.

Guess i will be installing my 9813 very soon...

 

[BASSMEKANIK 10+ year member]

i have the 7800 so we're in the same boat. i'm gonna call pioneer's support line and see if there's a way on the 780 or 7800.
i'd like to further point out that BASSMEKANIK is a tool by noting that a search of the deh-p7800mp manual (in pdf format) for the word 'full,' as in 'set your pre-outs to full' returns zero results.

it must **** to go out on a limb using 48 pt font, taking pictures of his HU, and scanning parts of his own user's manual to paste on his response only to find out he's wrong.

this is especially the case given that, for an encore, BASSMEKANIK showed us all what a valuable part of these forums he is by stating: "guess noobs cant read either"

the point is this: there are stupid questions, and this wasn't one of 'em.

to much of deh butt secks??? look a lil red in tha pic bro. every pioneer has it unless you are using something from the 80's . so stfu noob and dont get mad at me because you cant read.

 

[acold7dusta 10+ year member]

on my dads i think you can go into standby and change the slope 0 6 12 18 ( i think) you would pick 0

BTW he has the 6800

 

[squeak9798 5,000+ posts]

I noticed that the LPF on the Pioneer HU's cannot be set to pass or off. This whould mean that the lpf on the HU cannot be turned off to allow us to use the amps lpf crossover. I know that you are only suppose to use one crossover per line.
My amps crossovers on the sub channel is preset to 24db octave and i have my HU crossover options only from -18db, -12db or -6db.

Right now my 780 is set to 18db @ 80hz and my amp is set at 24db @ 80hz and im really worried that this is not setup right altough it sounds ok for now.

Any experts on this ?

You can certainly use them both. There is absolutely nothing wrong with using both the headunit's & amplifier's crossovers at the same time. In fact, many people intentionally use both to obtain the specific sound they are needing.

What it comes down to is the resulting sound. That is all that's important.

In the case of the Pioneer and it's ability or lack thereof to set the LPF to "pass"....it doesn't really matter. IIRC the lowpass frequency can be set as high as 200hz. In which case, the headunit's xover point is high enough out of the subwoofer's bandwidth that it won't really affect the sound much if at all. For example, if your amplifier has 24db/oct slopes and you have the amplifier's lowpass xover set to, say, 70hz....the signal going to be attenuated by -48db at 210hz. So having the xover set to 200hz is only going to be affecting a signal that's already being attenuated by over -40db. Not a big deal. So, if you only want to use the amp's xover....just set the HU's xover to 200hz. Badda-bing badda-boom.

But, as I said....you certainly can use them both in conjunction with each other (i.e. having them both set to 80hz). The resulting slope will be affected....but not inherently in a negative way. Like I said...many people do this intentionally. The only thing that's important is what obtains the best sound.

If using them both sounds the best (and given some of the previous postings...it possibly is?) then you are good to go and have nothing to worry about.

 

[suleman36 10+ year member]

How whould I be able to use a 24db slope like what is offered on my amp. It is not adjustable on my amp.

I understand the crossover freq part but what about the HU 18db slope and then the amps 24db slope ?

That adds up to -42db slope @ 80hz

Sorry this is confusing.