[BrandanK]

Matt,
I'm looking to do only drop in speakers.
it looks like that was your first step of your overhaul, but I'm not quite sure I understand what you did to factory "crossover". My car audio knowledge is shallow.

Brandan

[Msquared]

Originally Posted by BrandanK

Matt,
I'm looking to do only drop in speakers.
it looks like that was your first step of your overhaul, but I'm not quite sure I understand what you did to factory "crossover". My car audio knowledge is shallow.

Brandan

Okay, so the factory "crossover" is literally just a high-pass capacitor on the dash speakers. The door speakers get a full-range signal, and the dash speakers get everything above the high-pass frequency.
IIRC, the capacitor was 68uf. That would make it pass frequencies above 600-700hz, which is probably the lower limit of the stock 2.5" speakers. It is recommended that for any drop-in replacement, you keep some form of high-pass filter in the path to the dash speakers, because the high-energy in some low frequency music could damage them. I have seen people go without, and just send the full-range front signal to both the door and dash speakers, but you do so at your own risk.

When I did the drop-in speaker replacement (i.e. before I added the Kicker KEY amp with its built-in active crossovers), I cut the stock wire harness connectors off the stock dash speakers so I didn't have to cut the speaker wires (I knew I wasn't going to reuse the stock drivers). I also cut the high-pass capacitors off the stock speakers and added it to the factory connectors, and I connected all of that to the new Audiofrog GS25s. That I way, I could plug and play the GS25s into the factory location and harness. This is what I ended up with:



The female spades attach to the new speaker's terminals, and the factory connector block attaches to the factory speaker wires coming up through the dash.

However, if I were doing that again, I would use a bigger-capacity cap so I could lower the high-pass frequency to 200hz. The GS25s are good to that frequency and AF recommends that crossover frequency for them. I think I looked it up and figured that for a 4ohm speaker (which the GS25s are), a 200uF cap would get me where I wanted to be. That would have helped them integrate better with the door speakers. To so this properly, you need to find out the low-end frequency rating for the new speaker you're putting in and choose a capacitor accordingly.

[hayt51]

I installed the gs25 speakers in the dash and gs690 in the doors. Sounds a lot better as the original poster stated. I am thinking about adding Alpine KTA-450 Power Pack with the diy wiring harness. Would this amp fit under the glove box area and work with harness ?

[Msquared]

Originally Posted by hayt51

I installed the gs25 speakers in the dash and gs690 in the doors. Sounds a lot better as the original poster stated. I am thinking about adding Alpine KTA-450 Power Pack with the diy wiring harness. Would this amp fit under the glove box area and work with harness ?

Sorry, I thought I submitted a reply to this yesterday. Not sure why it didn't come through. The dimension for this Alpine are pretty close to those of the Kicker I used. It's slightly smaller in length and width. To my recollection, the length of the Kicker was a bit too long to fit neatly inside the “Multiuse Module Bracket." I would have had to cut/trim some of the bracket. Maybe the Alpine is just smaller enough to work - I'm not sure. The only way to know is to remove that bracket and trial fit the amp. That's not too hard to do, though. Another possibility is mounting it behind the passenger kick panel. The Alpine's lower height might be helpful there.

The DIY harness should be fine with this amp. The Alpine specs say it accepts speaker-level inputs, which is what you'll be getting from that harness. To power the door and dash speakers only - like I did - you'd send the amp only the front-speaker signals like I did. Connect the four outputs each to one speaker. You can use the Alpine's 120hz high-pass filter on the dash speakers to protect them, I guess, but this isn't really a proper crossover. You'll effectively be running both pairs of speakers full-range, which may or may not sound good (I really don't know). The factory limits the dash speakers to about 600hz-and-up using that 68uF capacitor that I mentioned in my OP. I'd switch that out to a 200uF cap to get the 200hz high-pass filter as recommended by Audiofrog for the GS25s. Note that my Kicker actually actively crosses the door and dash speakers, so my setup is a little different than yours in that respect. But yours should work with the passive high-pass filter, which is after all what the factory used.

[hayt51]

Thank you for the reply .As I am lost on this amp thing . I forgot to mention i did add bass blockers to the dash speakers. I guess the ones the gs25s calls for. The place I ordered from set me up with bass blockers. I didn't have the amp ordered yet so was just wondering on the fitment. but I went ahead and ordered it now. place i ordered from said i should not use the harness power and ground . They said off the battery and chassis ground . So i decided to just to put it in the trunk seems simple enough. How bad could it be after installing those dash speakers ,lol. Also was told I had to run the blue wire up front to the breakout harness. So that i would not have the amp on all the time. To be honest I know very little about amps and speakers.This post has been great. Could not have done without your knowledge and willingness to share it. Thankyou

[Msquared]

Originally Posted by hayt51

Thank you for the reply .As I am lost on this amp thing . I forgot to mention i did add bass blockers to the dash speakers. I guess the ones the gs25s calls for. The place I ordered from set me up with bass blockers.

Okay, then you're good there. You can turn the high-pass filters off on the amp.

place i ordered from said i should not use the harness power and ground . They said off the battery and chassis ground . So i decided to just to put it in the trunk seems simple enough. How bad could it be after installing those dash speakers ,lol.

That's part of what made me put my amp in the trunk too. It takes some time but it's not difficult work.

Also was told I had to run the blue wire up front to the breakout harness. So that i would not have the amp on all the time.

According to manual for that amp, if you're using speaker-level inputs like you are, you don't need that blue wire connected. It will probably work with it's "remote sensing" function (I assume it senses DC offset).

[hayt51]

I did see that in the instructions about the blue wire. But I wasn't sure. Could I ask what size bolts you used to mount plastic piece to mrc box? Picture looks like push pins. I bought a universal plastic panel from audio shop to make a mount for the amp .

[Msquared]

Originally Posted by hayt51

I did see that in the instructions about the blue wire. But I wasn't sure. Could I ask what size bolts you used to mount plastic piece to mrc box? Picture looks like push pins. I bought a universal plastic panel from audio shop to make a mount for the amp .

Those are three screws with torx heads and integrated washers. They are in the three threaded holes that GM used to mount the MRC module, so they are whatever thread size/pitch those screws use. These might have even been the OE screws and I reused them - either that or they were left over from some other project and happened to fit. I honestly can't remember. But anyway, if you have MRC then you have the same three screw locations that mount it to the trunk floor. I truly just emulated the way GM mounts their amps for the SS and Bose systems:

[ctrlz]

Originally Posted by Msquared

The female spades attach to the new speaker's terminals, and the factory connector block attaches to the factory speaker wires coming up through the dash.

Your harness mod looks good.
I might suggest slipping some insulation over the exposed leads on the cap so they can't touch and take the cap out of circuit.

[hayt51]

Well, I got the T-harness from gen5 Diy today tried to wire up and Iam confused on what wire goes where to make this amp work. I am using metra cable. Only place i have sound is to the rear speakers. Only because I just put the wires together for the rear. Any help would be appreciated.

[Msquared]

Originally Posted by hayt51

Well, I got the T-harness from gen5 Diy today tried to wire up and Iam confused on what wire goes where to make this amp work. I am using metra cable. Only place i have sound is to the rear speakers. Only because I just put the wires together for the rear. Any help would be appreciated.

Didn't Gen5DIY provide a color code for the harness wires? You should have four wires that need to connect to the amp's speaker-level inputs: Left Front Positive, Left Front Negative, Right Front Positive, and Right Front Negative. On my prototype breakout harness the colors for those were respectively: Yellow, Green, Black, White. But they may be different on yours if the rear speakers were also broken out. For this part I used the 16/4 cable to connect those breakout harness wires to the amp inputs in the trunk (like I wrote above, 18/4 would have been fine if I could have found it locally).

Then you need to connect the amp's outputs to your door and dash speakers.
I used the Metra 9-conductor "speedwire" to run all four channels (eight conductors, a positive and negative for each of the four channels) back up front from the trunk. I'm assuming you are going with one channel per each of the four front speakers, right? Referencing the diagram below, the factory wiring has a "Y" split for the front speakers so that one positive channel output from the A11 radio unit feeds a full-range signal to both the door speaker and dash speaker in parallel. In the diagram below, that "Y" is at J207 and J208. The Gen5DIY breakout harness taps in right where those four channel wires come out of the radio unit (2, 6, 8, and 3), so if you feed the amp outputs back into the harness and do nothing else, you'll have one amp channel feeding the left GS25 and GS690 in parallel and another amp channel feeding the right GS25/GS690. That's not what you want: you want one amp channel feeding each of the four speakers separately.




So what I did was connect the two channels for the GS690s by connecting those amp outputs back into the factory wire harness. That way I didn't have to attempt running speaker wires through the kick panels and into the doors. Then I ran new speaker wires from each GS25 down through the dash and over to the other two amp outputs in the speedwire. See the edited wiring diagram below. I left the disconnected factory speaker cables zip-tied to the new speaker wires so they wouldn't get lost behind the dash in case I ever want to use them again (can't imagine why, but who knows?). The sucky thing is that means you need to pull out the GS25s again to change the wire over. It's either that or pull the GS690s and run new wires to them. Pick your poison. Either way accomplishes the same thing: you've bypassed those "Y" splits in the factory wiring, used the factory wiring to connect either door or dash speakers to two of the amp's channels and you've run new speaker wires to connect the other two speakers to the other two amp channels.

[hayt51]

Yes my breakout out wire harness is different. White left front , Gray right front , green left rear, and purple right rear. I simply put the green and purple together and powered both rear seat speakers. Which left with white and gray for both dash and door that is what I couldn't figure out. Didn't realize the front door and dash where together in parallel. So I guess I will get to run new wires from the dash speakers. Thanks for clearing that part up. Hopefully I can figure out how to wire this thing up after that.

[hayt51]

Did you cut off your RCA jacks and run those wires up front for inputs. Iam being told that tis what I have to do to make this work. That means another metra cable upfront if so. I thought I only needed speaker level wires? Sorry For all the questions never done this before.

[Msquared]

Originally Posted by hayt51

Did you cut off your RCA jacks and run those wires up front for inputs. Iam being told that tis what I have to do to make this work. That means another metra cable upfront if so. I thought I only needed speaker level wires? Sorry For all the questions never done this before.

The RCA plugs on the amp inputs? You can either cut them off or install RCA plugs on the speaker-level wires going into them. I think I did the latter, but either way works fine.

There will only be four wires total going into the amp as inputs (two channels, +/- for each), whereas you'll have eight wires coming out of the amp to the four front speakers (four channels). With the amp in the trunk, it means you need to run the four inputs from the DIY harness up front back to the trunk and the eight amp outputs from the amp back to the IDY harness in front. For the former, I used 16/4 wire that they had locally at Home Depot (18/4 is fine and a bit smaller and easier to run if you can find it).* For the latter, I used that Metra 9-conductor speedwire. Both runs will use the same path under the passenger-side door sill trim and rear seat, so since you're running the speedwire already it's no big deal run the 16/4 for the inputs in the same path.

* You could use the Metra speedwire for the inputs too, but you'd only be using 4 of the 9 conductors and therefore it's fatter than necessary. I probably would have used it, but the 20' roll I bought wasn't long enough for two full runs. So that's why I bought the cheaper and smaller/easier 16/4 cable instead from HD.