I think my installer screwed up. Please take a look at my amp settings.

[davidc]

The amp is a Precision Power P900.4

The system doesn't sound good. Hardly any bass, and the mid and highs seem thin.

I am not a car audio tuner, however, I've been an audiophile for 40 yrs, so I am well aware what quality sound is.

The system was installed and tuned by a friend of a friend privately who has been the head of the install dept. at a Best Buy for about 5 yrs. Supposedly knows his field. I was not there for the install, and there was a falling out after I told him that the system didn't sound well when I went to pick up the car. I had told him that I like my music to be as "accurate" as possible, without any artificial bass boost.

The system is a Kenwood HDR-545U HU with no crossover settings being used except the subwoofer output crossover at 85Hz. (I believe it's a 12dB/oct slope.)

The installer said the system would sound best with the midrange and treble tone controls set to -6.

It's installed in a 2004 Honda S2000 convertible.

Please look at the photos below to confirm what I think are the settings. Don't take my word for it!

The door speakers are Boston Acoustics components (SC60) with a passive crossover between the 6.5in mid/woofer and tweeter.

There is a 12in Polk Audio 4ohm single voice coil subwoofer in a sealed box of proper size in the trunk.

It appears that the front crossover is set 1500Hz. Without a marking on the knob its difficult to tell, but if rotated fully CCW, the mark that would be at 20Hz is at about 10:00, and the x10 button is pressed in.

The rear channel is set to bandpass (BPF), and the buttons are out (x1).

Using the reference of the knob markings that would be at 50Hz and 20Hz respectively if rotated fully CCW, they both are at about 10:00.

So, for the rear channel subwoofer, it appears the LPF is set to about 180Hz, and the HPF is set to about 160Hz.

The subwoofer wires are connected to the RL- and RR+ terminals, which seems to be opposite of what the manual suggests for bridging the rear channels. The manual states: "If one subwoofer with 4ohm is used, bridge the amp using the (R+) & (L-) terminals.

If this is all correct, it doesn't seem to make any sense at all, and would account for the poor sound.

What do you guys think?

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[pickup1 5,000+ posts]

Mono is a left - right,so your correct.

High and low pass should be around 80-100...not bandpass.

 

[davidc]

Well, it appears with this amp that for the rear channels, you have to use "bandpass". It's sort of weird and has been talked about in the forums. If I could ask you to look at the photos it would be great. Also, it appears the HPF for fronts is set to 1500Hz, is that correct?

For the rear channels (subwoofer) I believe you have to use bandpass, but because of this, you can actually have the LFP HPF set with freq that are sort of "opposite" overlapping if that makes sense.

 

[bradl79 10+ year member]

Play with it urself

 

[JL Audio 5,000+ posts]

Play with it urself

offer him some real advice on what to set it to? i'm fairly certain he would indeed adjust it himself if he knew what he was doing 100%. It's better to confirm than to possibly worsen it.

 

[davidc]

Play with it urself

Awesome.

 

[davidc]

offer him some real advice on what to set it to? i'm fairly certain he would indeed adjust it himself if he knew what he was doing 100%. It's better to confirm than to possibly worsen it.

Thanks! I could easily adjust things from a textbook standpoint...I understand it all. But I had an experience guy do the install and tune. Am I correct in what I think the current settings are and that they make no sense?

As an aside...why is it that manufactures don't put a marking or hash mark on the knobs...?

 

[JL Audio 5,000+ posts]

Thanks! I could easily adjust things from a textbook standpoint...I understand it all. But I had an experience guy do the install and tune. Am I correct in what I think the current settings are and that they make no sense?
As an aside...why is it that manufactures don't put a marking or hash mark on the knobs...?

while I really can't answer your first part, some do put markings on their knobs but I have wondered the same thing on many amps. It needs to happen //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif on all amps.

I am sure someone will come in here and help you, keep_hope_alive or audio or something like that is a very helpful guy maybe he'll chime in.

 

[davidc]

while I really can't answer your first part, some do put markings on their knobs but I have wondered the same thing on many amps. It needs to happen //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif on all amps.I am sure someone will come in here and help you, keep_hope_alive or audio or something like that is a very helpful guy maybe he'll chime in.

Thanks much!

 

[Pyro_By_Nature 5,000+ posts]

Your settings do sound a bit odd. I would return the mid. & treble controls on the head unit to 0, change the frequency multiplier on the front channels to x1 and raise it up some so you're not at 20hz. See if that improves it at all.Might I also suggest switching the crossover to full on the rear channels, seeing as you're using the crossover in the head unit for the sub. This is just what I would do, so take it with a grain of salt.

 

[davidc]

Your settings do sound a bit odd. I would return the mid. & treble controls on the head unit to 0, change the frequency multiplier on the front channels to x1 and raise it up some so you're not at 20hz. See if that improves it at all.Might I also suggest switching the crossover to full on the rear channels, seeing as you're using the crossover in the head unit for the sub. This is just what I would do, so take it with a grain of salt.

What you say makes good sense....I just don't get what he was doing here....

BTW, one of my favorite old cars was my 88 CRX Si