funtimes

i have a similar amp (mine is from nak 98 ls400) i get all channels working except the sub. the sub just puts out a really faint output? i thought maybe there is a separate amp for the sub, but I don't think so. so i thought, maybe +b2 needs to be hooked up to my 12v battery to provide power to the sub channel on the amp? right now i am testing with only 2 out of the 4 rcas plugs feeding the amp, ie, just one white one red rca cable. (the head unit i am using only has 1 set of pre outs)? maybe the nak amp needs all 4 (ie, two whites two reds rca cables) to put together a sub sound? any help is much appreciated. also, i am confused on signal ground and ground and where each is supposed to go in relation to my car and head unit.

i will try to attach two different wiring diagrams one for a 95 ls400 nak and one for a 2000 ls400 nak, i think 98-00 had some differences added.

funtimes

hi i'm tryin' to attach the wiring diagram. my amp is the nak from ls400 1998. the diagram is from a 2000 ls400 nak...so...i have gotten all the fl fr rr and rl channels to work alright, but i can't get the sub to make much noise, its just real, real weak, not just "factory sub" weak. so i finally tried to get all four rca's leads into the nak amp...i maybe have an issue with a tried to basically make my own Y adapter type thing on one of the rca pairs because i also wanted to feed that pair to another amp i am using at the same time (a radio shack optimus xl-400, don't laugh it seems alright 90db snr beats lots of head units). so why can't i get the sub on the nak to work? why do car audio shops always say "well you will lose the sub when we install that aftermarket head unit, the factory sub you will lose, so you'll have to buy a new amp for the sub and probably a new sub"...is that bs? why do you lose the sub? i don't know if one can take an rca pair and try to splice in another rca pair line....isn't that just what a "y" adapter does? i get that the voltage on those preouts will take a bit of a hit, but... i just don't know why i can't get the sub working


lastly, why am i trying to use this nak amp? other than to make that trip to the junkyard less of a loss and to avoid spending more money on some other amp?
i am fairly happy with the xl-400 amp and i guess i could just use my head unit's amps for anything else i need, my head unit is a DEH-P4100UB

http://www.pioneerelectronics.com/PU...rs/DEH-P4100UB

its specs are:
http://www.pioneerelectronics.com/PU...-P4100UB?tab=B

1-bit D/A Converter Yes (8fs/16-bit)
Audio Features
Built-in Speaker Power MOSFET 50W x 4
Continuous Power Output 22W x 4

so, i wonder, doesn't the common wisdom say its better sound quality to not use the on board amp on the aftermarket head unit, but instead to, say, use an outboard amp like the nak? or are these new MOSFET things in today's head units game changers such that the sound quality is actually better from my head unit than using the nak? how do i tell if the sub channel is just blown on my nak? does the sub channel have its own amp+ wire? its own ground? sorry so many questions. does anyone know the specs on the nak amp like thd and snr and rms and what would be a comparble amp on the market today and price?

erupert66

I am trying to use some of the ideas in this thread to get my install working properly. I have a Pioneer AVIC 940BT head unit and I've wired it in but it's way too hot. a lot of hiss and on volume 3-4 its already blasting. I pulled the seat out and looked for a gain control on the Nakamichi amp (saw a reference that there was one) but found nothing. I am thinking about bypassing it, but i cannot find a pinout for the amp. the inbound leads are in the first plug socket and it's simple to color match, but, aside from figuring it out one speaker at a time, is there a reference for the outbound leads to the speakers? Do they follow the same color scheme but with a large gauge wire?

Truck is in limbo so I am hoping to find some answers quickly.

MNiern

I found a link that should answer your questions.

http://tlcfaq.com/main/2012/05/land-...stereo-wiring/


When I did mine I found something similar and really didn't have any trouble. I still have the LX and the stereo still sounds as good as when I installed it.

Good luck

erupert66

well, I ended up eliminating the AMP. It wasn't that hard. Power is passed through the amp and up to head unit, both constant and switched. Once I fig out that combo, I jumped those and the speaker wires were easy as they color match in and out. Once I figure out how to post a few pics. I'll post them.

Ryanlong

I am a new member so hello everyone.
I have the Mark Levinson Audio in my (New to me) 2003 LX 470.
It sounds like all the speakers are blown and distorted.
I am assuming it's just a speaker problem not an amp issue. I could be wrong.
Has anyone found an alternative speaker system that will fit in its place?

Thanks

allmac

Hi,
I see this is an old post, but I just came across it,as I am trying to to replace my factory radio with a Kenwood unit,in a 2000 lx470,
can you help me locate a plug in kit.
thanks Mal