924Board.org

[maireeka]

I can't get the subwoofers to do their job on my new system. I'm not sure how to do so. I have a 4 channel sony xplod amp.

rca cables go from the head unit for both front and back speakers.(there are two sets of plugs for rca's on both the amp and the head). The 12 inch subs are wired as the back speakers, and the 6x9 speakers are wired as the front, both from the amp. No speakers are run via conventional wire from the head unit as of yet.

When I turn up the volume, i hear a lot of mids and trebles instead of the punchy lows I used to hear when I had my old system, using the same two 12s. (that rules out crappy speakers.) I think it's got something to do with the way I've got the amp set up. Could someone explain to me the optimal way to set my amp so that the 6x9's will power mids and the 12's will hit really hard lows? Right now I have the lbpf and the hbpf (i think that's what it's called) switches both on. The level for the rear speakers is up to like 3/4, and the fronts are set to 1/2.

If i turn bass up on the head unit, it starts making the 6x9's sound shitty, because they need to be getting mids, not lows. When I turn fade on, the subs get louder, but the 6x9's don't. I want my 6x9's to sound the same, and the subs to hit. How would I set it up to do this?
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1977 Porsche 924 red and READY!

[Diesel]

Is the antenna up?
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Dan Flanagan--2002 VW Jetta TDI, 83 Mercedes 300D,83 Mercedes Euro-240D

[Kenodog]

In order to get some 4 channel amps to work with 2 rca inputs you'll need to remove or add a jumper.It should say whether the speaker wires hook up to say A & C , B & D or A & B , C & D. Is this making sense?That's how my old Sony 2-3-4 channel amp was anyway.
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1979 Euro 931, Olive
1981 931, Sabine
1991 Ford Ranger XLT 4x4, Ricky
1996 Ford E-350 ex-FedEx Van
2014 Mazda CX-5 (Kinderwagon)
2019 KTM 790 Adventure
2024 KLX300
2024 KLX140

[maireeka]

I think that the amp can't power the subs enough with the 6x9's hooked up as well. They are 900w subs my dad bought for me. (he's not an audio guy, but he knew it was a deal.) the amp maxes at 80w per channel or something, and i don't think it's enough. I'm going to wire the 6x9's to the head along with some 5.5's that came with the car, then have only the subs running off of the amp. that should at least change it up a bit.

Also, I don't think there are any jumpers on my amp. I read the instructions that came with it and it didn't say anything about that. (it's a factory refurb sony amp)

Patrick
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1977 Porsche 924 red and READY!

[Richard]

It sounds like to me that you need a better crossover (either active or electronic) to seperate the bass from the high and mids. If the subs don't have a low pass filter on them, then they are getting signals from all over the spectrum. Look at the sony explode manual again and see if it has a crossover built in and learn how to adjust it. If that doesn't do it, guy out and buy one.

[maireeka]

okay. Should i try the idea i talked about in my last post before that?

Are the two switches on my amp crossovers? I think they are. It says like hpf or hbpf or something and lbpffpf.
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1977 Porsche 924 red and READY!

[Richard]

If there is enough power in the head to give a clean signal to the 6x9's it would be a great idea to dedicate the subs to the amp. In fact I think you have no choice. twelve inch speakers are huge and you really only need one in a car that is not in competetion (but I'm old fashioned). You will have to bridge the amp channels to give you a mono amp. The sony xplod series (I looked at website) all have a 50-300Hz low pass filter. lpf probably means low pass filter. Good luck. Remember you can ruin your hearing with elevated sound levels.

[My924gtc]

[Sleykin]

I don't think you want both the HPF and LPF on at the same time. The HPF would essentially block the low and midrange and would be used for running tweeters/upper mids. The LPF would block the midrange and up frequencies. Unless they are using the terms wierd. The other point to be very sure of is polarity. For low frequencies the polarity is very significant. If the 2 subs are 180* out of phase they will kill most of the bass. I would only run the subs from the amp, but you may want to add a pair of mids to the rear to fill.
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Glenn Neff
Medford, OR
87' 924S

[maireeka]

OK, it's all set up. My last problem is only the right sub is hitting. It is probably because of the way I have the RCA's hooked up at the amp or the head. Can someone explain how I'd hook it up from the head to the amp if both the amp and head have a FRONT and REAR set of jacks for the RCA cable? Am I just doing it as rear, or do I split it somehow? I've got it hooked up like in this pic right now:


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1977 Porsche 924 red and READY!

[macBdog]

Ok easy fix for this one. RCA plugs and sockets like the ones on your amp and head unit are in pairs of red and white. So red is the right side and white is the left (or vice versa, cant remember). You need to connect one red and one white socket on the head unit to one red and one white on the amp to get a stereo pair.
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1979 931 with a 350 chev
1973 911E with EFI

[maireeka]

I thought I was trying to bridge it? If i hook up red to red and white to white, it won't be bridged, I don't think. Maybe the thing on the instructions is wrong.
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1977 Porsche 924 red and READY!

[CMXXXI]

[Sleykin]

You may have the amp correct but the head unit is wrong. You have simply bridged the fader control for the Right channel. The amp looks wrong too but without seeing the bootstrap arrangement I haven't a clue. Normally the bridging is done at the output side.
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Glenn Neff
Medford, OR
87' 924S

[Richard]

The head is hooked up red and white and so is the amp in. To bridge the amp you hookup the + of channel 1 and the - of channel 2 going to the speakers. At least that is way an amp I have on a shelf is done.