I have a Sony Xplod CDX-MP40 head unit, a MTX Blue Thunder Pro 752 amp,
and a MTX Thunder 250D amp. I had some questions regarding the wiring.
The Pro 752 has a built in x-over but only has one set of RCA
connections. I assume that this is for the input from the head unit.
How am I going to wire the two amps? The head unit has front & rear
preouts. Will this enable me to have one set of RCA's going to the
high amp and another going to the sub amp?

The sub amp has an RCA input and output. If it has a built in x-over,
will I be able to wire this one from the head unit and then to the high
amp?

I am new to the car stereo scene and appreciate any help you can give.

Thanks,

Sam

"Sam" wrote in message
ups.com...
I have a Sony Xplod CDX-MP40 head unit, a MTX Blue Thunder Pro 752 amp,
and a MTX Thunder 250D amp. I had some questions regarding the wiring.
The Pro 752 has a built in x-over but only has one set of RCA
connections. I assume that this is for the input from the head unit.
How am I going to wire the two amps? The head unit has front & rear
preouts. Will this enable me to have one set of RCA's going to the
high amp and another going to the sub amp?

Exactly. You didn't mention what speakers you would be driving, but this is
the configuration you would use for the RCA's. One set of RCA's will run
from the HU to one amp, and another set will run to the second amp. I
assume you will use one amp to drive front speakers, and the second amp to
drive a subwoofer (this is the most typical configuration).


The sub amp has an RCA input and output. If it has a built in x-over,
will I be able to wire this one from the head unit and then to the high
amp?

You WILL NOT want to do this. The reason is that you will lose any volume
control of the second amp. From the HU, you will want to be able to control
the volume of each amplifier separately so you can, say, adjust ONLY the
subwoofer volume. If you use a single pair of RCA's from the HU, you will
lose this control. You would likely ONLY use that sub amplifier RCA output
if you were going to have a second subwoofer amplifier. You mentioned that
the sub-amp has an X-over, does your other amp havean X-over as well? Most
amps these days do. Your HU, unfortunately, does not have any built-in
X-over so if your high-amp does not have one you will most likely need to
buy an active X-over (active means it is powered and works between your HU
and amp). I have NO DOUBT that you can find a used one on Ebay for $10-$15.
This will be necessary to restrict low frequencies going to your high-amp
speakers. Hope this helps.

MOSFET

I am new to the car stereo scene and appreciate any help you can give.

Thanks,

Sam

Thank you sooooo much!!!

My high amp does have a x-over. Since I will wire each amp separately
from the head unit, how does the signal that gets crossed over get to
the sub amp? Or does this even occur? I am not too sure on how this
works since I am just a rookie. :-(

The subs that I have are 3 JL Audio 10W3's. The highs that I have are
Alpine SPS 171a's; 6.5" components.

Thanks again!!

Sam

"Sam" wrote in message
oups.com...
Thank you sooooo much!!!

My high amp does have a x-over. Since I will wire each amp separately
from the head unit, how does the signal that gets crossed over get to
the sub amp? Or does this even occur? I am not too sure on how this
works since I am just a rookie. :-(

I don't understand your question. The signal that gets to your sub-amp gets
there because you run an RCA cable from your HU to that amp. This seems
pretty straight forward to me. Your HU has two sets of pre-amp (RCA)
outputs. One set goes to one amp, the other set goes to the other. Then
your sub amp employs it's X-over to restrict high-frequencies, and your
high-amp employees it's X-over to restrict low-frequencies.

If you are still confused, perhaps try re-wording your question. Good luck!

MOSFET



The subs that I have are 3 JL Audio 10W3's. The highs that I have are
Alpine SPS 171a's; 6.5" components.

Thanks again!!

Sam

OK. I understand that the signal gets to the sub amp through the RCA
cable.

Sorry for the confusion. I think I understand what you are saying.
Are all tones sent to the amps and then the x-over in each amp
determines which tones to send to the speakers? What happens to the
tones that are not played by the other driver?

Thanks,

Sam

"Tones"? I guess I'm still not getting the essence of your question. Your
HU sends out full-range signals (20Hz-20kHz) to both sets of RCA outputs.
The X-over's in each amp restrict certain frequencies before they are
amplified. For instance, the sub-amp will restrict frequencies above 80Hz
while the high-amp will restrict frequencies below 80Hz (you do not
necessarily have to have these match like this, do what sounds best). The
frequencies that are removed from the signal by the X-overs just disappear
(is this your question?).

MOSFET

"Sam" wrote in message
oups.com...
OK. I understand that the signal gets to the sub amp through the RCA
cable.

Sorry for the confusion. I think I understand what you are saying.
Are all tones sent to the amps and then the x-over in each amp
determines which tones to send to the speakers? What happens to the
tones that are not played by the other driver?

Thanks,

Sam

Yes. Thank you very much. That was exactly what I was wondering. I
was confused as to what happened to the frequencies that the x-over
restricted.

Thank you again!!! I am sure that I will have plenty more questions to
come.

Sam