1988 325IX My $500 Stereo Install

[greentalks43]

Props on the build! I hope it sounds as great as it looks!

[moto650]

Props on the build! I hope it sounds as great as it looks!

Me too. Ha:D

[moto650]

So I've been digging more into the 4 or 5 channel thing to make sure I've got all the inputs and outputs wired on the amp right.

Actually read the amp manual front to back, looks like I don't need to do anything.
With 4 channels of input and 4 channels + 1 channel for subwoofer on the output, I just flip the switch to 4CH mode and bob's your uncle, it will sum the 4 input channels and use that for the 5th (sub) output.

Am I crazy? here's the excerpt from the manual.

MODE
The Power 5500 comes equipped with a 4CH/5CH MODE switch and can be
configured for two different input modes: 4 channel or 5 channel. In 5 channel
mode, the subwoofer channel is a sum of the RCA inputs 5CH/1 and 5CH/2.
For head units with a mono SUBWOOFER output, you should select 5 channel
mode and use either the 5CH/1 or 5CH/2 as the input. In 4 channel mode the
subwoofer channel is a sum of CH1, CH2, CH3 and CH4. This mode should be
used for head units without a separate SUBWOOFER output.

[Schnitzer318is]

I would still run it in 5 channel mode and do as I described. I would rather my sub input be a sum of 5ch/1 and 5ch/2 than a sum of all 4 channels.

My reason for this is that when you are tuning you will not be able to use any of the head units tuning capabilities (crossovers). You will have to do everything at the amplifier. This is not bad... just inconvenient and much more time consuming. I'd much rather be able to tune everything I could at the front of the car and just use the amps crossovers for fine tuning.

^That's just a personal preference though. As you said you can run it in 4 ch mode and have no problems.

[moto650]

With the on again off again nice/not nice weather I spent time on another project :nice:


but this isn't about shed building, this is about raw, angry german powwa :hitler:

I started putting the dash together and put in the HU. I went the 4channel mode route and let my amp figure out the signals. I think I'll have enough flexibility with the LPF and HPF to tweak it such that I get good sound from the speakers and good bass from the sub. We'll see. I should get off my lazy butt and call that Luke guy about tuning. Enough rant, pics.


Put it in the dash, fits good

[moto650]

Hooked up the amp.
Found these terminals at home depot. They're not uber cool audio deals, but those uber cool audio terminals would mean I have to cut my primary wire which I'm not keen on. Anyways, these were cheap.

I did have to enlarge the hole just a scoche.

Put some heat shrink on it just cause

Hooked er up

[German Audio Specialties]

I would still run it in 5 channel mode and do as I described. I would rather my sub input be a sum of 5ch/1 and 5ch/2 than a sum of all 4 channels.

My reason for this is that when you are tuning you will not be able to use any of the head units tuning capabilities (crossovers). You will have to do everything at the amplifier. This is not bad... just inconvenient and much more time consuming. I'd much rather be able to tune everything I could at the front of the car and just use the amps crossovers for fine tuning.

^That's just a personal preference though. As you said you can run it in 4 ch mode and have no problems.

NO! Do NOT do this, you are wasting input voltage! Use the crossovers in the amp and use the 4 channel mode, the crossovers are better than the ones on the deck and you will be far better off, soundwise.

the summed function works flawlessly, but do NOT turn on the High Pass Filters in the deck.

Luke

[moto650]

NO! Do NOT do this, you are wasting input voltage! Use the crossovers in the amp and use the 4 channel mode, the crossovers are better than the ones on the deck and you will be far better off, soundwise.

the summed function works flawlessly, but do NOT turn on the High Pass Filters in the deck.

Luke

Oh cool. I'm glad I did it the way I did then. And yes, the HPF are OFF on my amp.

Small update tonight.
When I first connected the radio a couple weeks ago, I noticed that the radio would not power up unless I turned on my headlights and then it wouldn't remember it's memory. Also I had over an amp quiescent current draw. Soo.. I figured I'd first do the whole check for corrosion thing, so I cleaned all my taillight bulb sockets and the rotating plug thing with electrical contact cleaner and also my diode pack plugs and the 3rd brake light connections.
Still had too much draw so a buddy helped me monitor a meter while I pulled fuses. 21 was the ticket.
I pulled the radio and inspected the wires to make sure I'd wired it correctly. While I did, I remember reading one guy say his OE wires were not to spec with the ETM. Checked mine and sure enough, gray/red was NOT illumination, it was ignition hot and red/green was illumination (on when headlights) No idea why, but hey, I'm the retard who didn't check this when I was hooking it up in the first place.
I corrected this and it took care of my quiescent draw issue so now I'm mostly happy. I have no idea about tuning, so I think I'll take advantage of my phone call to Luke that comes with purchase of Lukebox and give him a buzz. It does sound pretty good, but it seems to me I need to adjust the LPF ( so I get rid of some of the drone? and get it just to punch in for the beat portion of the music )

[dwvw]

Nope, You want the HPF ON at the amp, but OFF at the deck. If you turn it on at the deck you will lose bass as it is feeding your amp, in 4 channel mode.

Another reason to always use the crossovers at the amp, is that if you lose power to the deck, you won't have to reset all the crossovers.

[Nick_S]

Let me preface this. I know nothing about car audio, I'm not an expert here at all.

Funny you started this thread with this sentence. Had you not said that, I would have figured you do this for a living. Seriously nice work. I've seen much worse installs done by "professionals". I bet it sounds great, great write up too :up:

[moto650]

So, I worked up a little wire diagram of how I've hooked everything up.

[moto650]

Okay. Not to proud to admit mistake here.
So I have GC Koni yellows, top adjust.
Before let me stress that... before you install your awesome Lukebox, drill the trunk side panels so that you can get your adjusters on and actually access your fancy shocks.
I absolutely forgot about this and getting the LB out was a PITA. Not just the box, but I had all my wires... bla bla. Anyways, trust me, drill first. I used a 2 1/2 hole saw running backwards, Going forward grabbed too much, backwards works just fine.
You start with this

Drill hole

Tada, now you can get your adjuster knob on there to adjust the shock. ;)


Yeah, I'm a dumb arse for not thinking of this before but... yeah. Do it. Heck, just do it even if you're only planning on top adjust in the future.

[StereoInstaller1]

Damn.

If that were any nicer, I would call BS on all that "stereo install newbie" talk.

in fact...well, yeah, I believe you, but just barely.

Rock on!

Luke

[bernzpeed]

this is the best install thread I've ever come across.

[Schnitzer318is]

NO! Do NOT do this, you are wasting input voltage! Use the crossovers in the amp and use the 4 channel mode, the crossovers are better than the ones on the deck and you will be far better off, soundwise.

the summed function works flawlessly, but do NOT turn on the High Pass Filters in the deck.

Luke

Really? Hmm... I've always used 6ch output head units so I figured that summing all of the channels for your sub output on a 4ch unit would render all head unit options unusable.

You are saying that is fine and to do all your tuning at the amp/s. I didn't realize by tuning at the head unit you are dropping your input voltage to the amps. Is that the case with using a standard front/rear/sub output setup as well? Or only in this case where you are utilizing a summed signal?

Just want to clarify for myself and others.

Sorry for the OT moto, and the bad advise apparently, we are all still learning here. Your install is looking great and I'm sure will sound great with some info from Luke on tuning.