Stereo Questions - amp and back panel

[kyngfish]

Just got done sorting the suspension in my car. Next on the list is the horrible stereo. Got rid of my early aughts Pioneer HU last night and put in a reasonably austere Alpine unit with amber lights to match a little better and which automatically connects Bluetooth rather than the 5-step Black Magic I needed to perform with the old system. Check.

A set of Infinity Kappa 6.5s are on the way to replace my Walmart grade boy racer 5.25s in there now which sound like they came from a 1999 iMac.

A couple of questions.

- Theres a little metal box under the dash under and to the right of the head unit. Is that stock or some kind of aftermarket amp?

- Reading through threads in here I’m likely going to convert to a two channel system and get an amp in there and possibly a small under seat woofer. Is there anything special I need to do to stop getting signal to the crap rear speakers? Or just disconnect the wires at the speakers. The HU install only had two positive and two negative leads. So I’m wondering if that box I’m looking at under the dash splits the signal?

My audio experience is in home systems not car systems. So appreciate any pointers.

[911obgyn]

What year car?
The stereo in my 85 had front and rear fader in console which had common ground
Not comparable with a modern stereo. I had to run new wires to the front and got some rear speakers that fit. I am not an audiophile but spell check let’s me use the word.

[kyngfish]

Mine an 86. It already had an after market head unit. When I ran the new system I connected the speaker wire to what looked like the stock system which loooooks like it’s running into the box pictured below. There’s a picture of the box and the wiring. Also a random disconnected connector. Not sure what that’s for. Any insight appreciated.

[kyngfish]

For the record. What I am reading in other threads is that 2 channel in these cars is maybe better than four. So looking to eliminate the rear speakers.

Or if four speakers are better. Love to hear opinions.

[Hotshot]

That plug is for Autoheat, which you prob don’t have but the Harness includes it.

The box is your cruise control module.

86 had the fader in the console. My set up bypassed it.

[brshap]

Originally Posted by Hotshot

That plug is for Autoheat, which you prob don’t have but the Harness includes it.

The box is your cruise control module.

86 had the fader in the console. My set up bypassed it.

Do you happen to know if its the same for an 84? I'll be installing a new stereo soon and can't find a wiring diagram for the year.

[kyngfish]

Got it. Thanks. Any idea where that fader might be or where the signal is split. Because in the wiring I see two brown wires and two orangish wires one each has a stripe and one is solid. I’m assuming that’s just left and right channel positive and negative. Not clear on how the rear speakers are getting signal.

[Hotshot]

Originally Posted by brshap

Do you happen to know if its the same for an 84? I'll be installing a new stereo soon and can't find a wiring diagram for the year.

I don’t think many 84s had the fader. There was a single console slot for it.. as in 86 they re designed the look of the column inserts.

A guy in my lol all club with a 84 is un installing his rear speakers as he wants it stalk.
He was saying the only had up front speakers.

Look at the part manual. 84-86. The 84 rear shelf shows no speaker holes.

[Hotshot]

Originally Posted by kyngfish

Got it. Thanks. Any idea where that fader might be or where the signal is split. Because in the wiring I see two brown wires and two orangish wires one each has a stripe and one is solid. I’m assuming that’s just left and right channel positive and negative. Not clear on how the rear speakers are getting signal.

Those are the speaker wires. BN/RT and BN. They should meet up with the fader in a 6 pin connector and the fader will have BLK, 2 Grey, Grn, Blue, red wires.

Mine was totally bypassed. And re wired. Only reason for the fader is it wasn’t a feature in the decks back then..

[kyngfish]

Cheers. Thanks. Right now I’m on the bypass and go 2 channel train. Let’s see how I feel in a week.

[911pcars]

First, ID the Alpine stereo (aftermarket?) and try to obtain a user install manual. It should show the speaker wire color codes and how many speakers it can control. Aren't most contemporary head units set up for 4 speakers? It has Bluetooth, so it's fairly recent. If so, the L-R/Frt-Rear fader control is usually built in.

Sherwood

[kyngfish]

I bought the alpine unit new. I know what it is . That isn't the question I'm asking:

- I've heard that 2 speaker setups in these cars are as good or better than 4 speaker setups, because 4x6 speakers simply aren't very good and the back deck doesn't have much space behind the speaker. (unanswered)

- I wanted to know what I needed to do if I wanted to bypass the rear speaker (answered - bypass the fader down under the console).

[brshap]

Originally Posted by Hotshot

I don’t think many 84s had the fader. There was a single console slot for it.. as in 86 they re designed the look of the column inserts.

A guy in my lol all club with a 84 is un installing his rear speakers as he wants it stalk.
He was saying the only had up front speakers.

Look at the part manual. 84-86. The 84 rear shelf shows no speaker holes.

My 84 appears to be stock and has rear speakers. In fact I just pulled them the other day and they match the fronts and say "Made in West Germany". Have to believe they're original.

[911pcars]

Originally Posted by kyngfish

I bought the alpine unit new. I know what it is . That isn't the question I'm asking:

- I've heard that 2 speaker setups in these cars are as good or better than 4 speaker setups, because 4x6 speakers simply aren't very good and the back deck doesn't have much space behind the speaker. (unanswered)

- I wanted to know what I needed to do if I wanted to bypass the rear speaker (answered - bypass the fader down under the console).

While front speakers are usually the direction we listen to voice and music (unless you have your back to performances), rear speakers can fill in sound as if bouncing off a back wall. What sounds better is YMMV. AFAIK, I haven't seen any objective studies that indicate 2 speakers in a 911 repro sound better than 4 (or 5). What's wrong with 4x6" speakers per say? Or is that four 6" speakers? Unclear.

If rear speakers are wanted, there are enclosures that sit on the rear deck below the rear window.





Sherwood

[kyngfish]

Wild! I could probably build that pretty easily. I sort of love it.

[1979-930]

Originally Posted by kyngfish

For the record. What I am reading in other threads is that 2 channel in these cars is maybe better than four. So looking to eliminate the rear speakers.

Or if four speakers are better. Love to hear opinions.

I have a amp but I connected the new rear speakers to the deck power just for added fill sound in the space and increased volume when the windows are down. Without the rears you need to really crank the volume of the fronts.

I went with the Infinity Kappa speakers too for the value. I purchased a small 4 channel AMP with crossover that fits under the drivers seat to power the front speakers and a slim line 6" SUB that fits under the passengers seat. The sub is what really brings depth to any system.

[Koizumi]

84 does have fade. I ripped mine out a decade ago tho.

[Hotshot]

Some PO did a good install on mine in the 90s. Boston Acoustics had these little riser boxes. Nice n clean. I still use them.

[Tremelune]

You're on the right track. If you want a "fuller" sound that isn't being supplied by door/dash speakers, what you want is a sub.

Disconnecting the wires in the rear speakers should be all you need to do. An amp and modest sub should fit under the two front seats without much issue.

[Tremelune]

Rear speakers can "fill out" the sound by virtue of there being more space for larger drivers in back, but they also serve to confuse the sound stage. You'll hear folks turning down the treble in the rear and lowering the volume so you can barely hear it (but notice it's there)...It's mostly a crutch to avoid installing a subwoofer and/or amp.

For the same money, two front speakers and a sub will sound better than four full-range speakers...and I would argue better than four speakers and a sub as well in a small coupe that rarely sees rear passengers.