Ok, so some of you may know, I installed 2 sets of Hybrid Audio Clarus comps in my E39. I am currently running 2 amplifiers; a 4 channel Planet Audio Hybrid Vacuum Tube amp and a monoblock Zstat amplifier. I had them professionally installed because I didn't have the time. Both amps are running off a David Navone 4 channel LOC. Here is the issue....when I turn the HPF down, the subwoofer bass increases but also puts my front channel response too low. If I tune the front stage to where it sounds great, the sub is barely noticeable. The gain on the mono amp does work but it's maxed out and still very little response. I basically need help to figure out why the 4 channel filter has so much influence over the output of the sub. Thanks in advance!

Sorry if I am just overlooking something simple. :help

they should be 2 totally separate systems... they should not be influencing each other. They are hooked up separately from each other right?

Since I am running 6 channels off of a 4 channel LOC and I have front and rear fade with my mid range, I am assuming that something is not correct...

So do you have 2 channels off the LOC to the 4ch amp, then the other two to the monoblock? Or is the monoblock daisychained through the 4ch amp?

Very strange. Let me get this straight.- Your sub is running off the mono amp, and your components are running off of the other?

When you lower the high pass setting on your (high?)amp, the bass in the subwoofer increases? If so, something is not right.

Please clarify which amp you are doing this on and I can try to diagnose it further.

I'm guessing that the amp is daisychained. I didn't do the wiring so I cannot be sure. But the 4 channel amp has all 3 sets of RCA's being used.

OK, if 3 sets are used on the 4 channel amp, then yes it is daisy chained. Here's what I would do.

Go to rat shack and get 2 Y rca's (one male-2 female). Use 1 pair of LOC outputs and the Y adapters to hook up the 4 channel amp. Then use the second set of LOC outputs to the monoblock. If this solves your problem (which I assume it will) you can opt for higher quality Y adapters if you feel the need. The rat shack ones should be sufficient though.

Depending on the amp, the "preamp outs" used for daisychaining may not be 100% independent.

The mono amp only has a LPF, a subsonic boost and a gain. I am adjusting the 1+2 HPF on the 4 channel and that is boosting or taking away from the sub.

The mono amp only has a HPF, a subsonic boost and a gain. I am adjusting the 1+2 HPF on the 4 channel and that is boosting or taking away from the sub.
I hope you meant to say LPF.........

OK, if 3 sets are used on the 4 channel amp, then yes it is daisy chained. Here's what I would do.

Go to rat shack and get 2 Y rca's (one male-2 female). Use 1 pair of LOC outputs and the Y adapters to hook up the 4 channel amp. Then use the second set of LOC outputs to the monoblock. If this solves your problem (which I assume it will) you can opt for higher quality Y adapters if you feel the need. The rat shack ones should be sufficient though.

Depending on the amp, the "preamp outs" used for daisychaining may not be 100% independent.

I already have those in use. I'll have to take the LOC out and try to trace where everything is going.

Any easy way to check this is to remove one pair of the RCA's that go into your 4 channel amp (from the LOC).

Plug them directly into your mono amp and see if your sub works better. If it does, then your 4 channel amp is controlling the output like Streetoc192 said. The Y- adaptors should do the trick, but I would try this before you go spend more money.

One of the biggest problems with LOC's occur when one input wire is out of phase. This would be the next place I would look if the above doesn't help.

My guess is that you've got the RCA to the subwoofer amp daisychained from the 4 channel amp. Usually the 4 channel amp has a full range pass through but I'd say you've got a setting wrong on the 4ch amp and the pass through signal is being filtered by the HPF on the 4channel.

What 4channel amp have you got (exact model number please). Maybe the answer is as simple as flicking a filter switch on the 4ch amp

If it's the HVT754 then the download for it is here:http://www.planetaudiousa.com/support/index.php?_m=downloads&_a=viewdownload&downloaditemid=9
Only got slow internet at the moment so will download and have a look at it later

It is the HVT-754.

i would take the advice of splitting the rcas for the rear signal and running them directly to the sub amp.

something funky's going on w/ the signal being passed through the first amp.

Ok, Thank you Rogan for posting the manual.

If I can read it correctly, make sure the switch for the Line Selector is set to Low pass. This should fix your problem.

It also appears that the bass and crossover frequency contol may control your slave amp (sub amp). I would suggest setting this to about 70hz or lower.

Yep, on HVT754 "line selector" = low, and "low pass" = clockwise to 500hz

On sub amp, turn gain down and set lpf to around 80hz

Yep, on HVT754 "line selector" = low, and "low pass" = clockwise to 500hz

On sub amp, turn gain down and set lpf to around 80hz

Ok, I will try this when I get home this evening. Thanks guys! I'll post results tomorrow morning.

Ok, I did as Rogan suggested and it made a world of difference. Now when I fade from front to rear, I can still hear the sub. The sub is extremely loud and now I'll have to probably go pick up another 12. If the guy would have wired all this correctly, I would have my good 2 channel amplifier and not need this class D mono amp. I am picking up a good deal of noise from the rear tweeters so I'll have to figure that out. I hate engine noise. Thanks guys!

Engine noise is 95% grounding. Check how the amplifiers have been earthed. I'd be using earth and power wires the diameter of my small finger and the amps should be earthed to the same point. The earth should be grounded to bare metal. (Then cover with something like vaseline to prevent rust)

ground to the battery.

it's right there!

Rear tweeter??

what's going on here.....:shifty

What are you asking?

i think he's suggesting that rear speakers are for the non-sq oriented folks.

but that's alright, you did what sounds best to you!

find the source of the noise?

:D

I dislike high frequencies coming from behind me...it totally pulls the sound stage back.

But some people like that...My fiance likes to have her speakes faded all the way to the rear...weird...


So is the problem fixed?

:D

I dislike high frequencies coming from behind me...it totally pulls the sound stage back.

But some people like that...My fiance likes to have her speakes faded all the way to the rear...weird...


Are you sure you want to marry her with preferences like that? Maybe you should run while you still can. :)

Are you sure you want to marry her with preferences like that? Maybe you should run while you still can. :)
:rofl:

lol!

:rofl2































:shifty

Boy, I didn't think it would get that good of a response.

Boy, I didn't think it would get that good of a response.
The audiophiles get it :)

I've actually been given the go to redo the audio setup in her accord. It's going to be pretty basic, but her 6x9's won't be playing anymore high notes...that's for sure!

When she fades the sound to the rear all she'll get is some sweet cdt or tang band low notes :D