Hozer's 2014 Sierra Audio Upgrades

Hozer · October 18, 2015

Hozer's 2014 Sierra audio upgrades

Thanks to great information and pictures in other threads, I was able to perform a clean and relatively easy upgrade of the audio in my 2014 Sierra. I thought I'd return the favor by posting my build here to help others with the information.

Starting Point: 2014 GMC Sierra crew cab with 40/20/40 front bench seat. Non-Bose stereo with 8" Intellilink sytem and no factory navigation.

Goals:

1a) Ditch the completely crap stock speakers that had no real volume, had bad response, and one of which was popping and scratching.

1b) Add an amplifier with good but not crazy output. The stock head unit doesn't have enough power to make any aftermarket speaker sound decent.

2) Add an amplified subwoofer for some significant base.

3) Keep the entire install looking as stock as possible.

4) Do not cut factory wiring beyond just the speaker leads right at the speakers.

Components Used:

Amplifier: JL XD700/5v1 with HD-RLC

Rear Door Speakers: Infinity Reference 6032cf, XTC 6 1/2" speaker baffles.

Front Door Speakers: Infinity Kappa 62.9i, XTC 6 1/2" speaker baffles.

Dash Speakers: Stock for now; Faital Pro 3FE22 later if needed

Subwoofer: JL 10TW-d4 or 12TW3-d4, likely to be a JL CS112TG-TW3 sub/box combo.

Currently using my old Orion XTR Pro 10-d4 in a box from my previous truck.

Head Unit: Stock

Line Output Converter: None - using high level settings on the XD700

Equalizer: None

Wiring Harnesses:

1) Metra 71-2107, aka 'reverse harness'. Male end which connects to factory stereo. Use to get audio output from the head unit and splice to RCA cables for amplifier input. Purchased through www.installer.com as they were basically the only source available.

2) Metra 70-2057, aka 'amplifier bypass harness'. Female end which connects to the factory speaker wiring harness. Use to send output from amplifier to the stock wiring going to each speaker location. Available through Amazon.com or Installer.com

RCA Cables: KnuKonceptz - Karma SS 4 channel 6 meter

Speaker Wire: Stinger Speedwire - 9 conductor, 20 feet; some 10 gauge Stinger subwoofer speaker wire I had laying around

Fusing: Stinger 100 amp breaker

Power Wire: KnuKonceptz Kolossus Fleks Kable - 4 gauge, 20 ft

Amplifier Mounting Board: 3/8" plastic cutting board from Wal-Mart

Miscellaneous Parts: tinned copper 4 gauge ring terminals, 4 gauge rubber grommet, heat shrink tubing, zip ties, 1/4" bolts and nylock nuts, JB Quick

Basic timeline (leaving out lots of detail):

1) Heard right rear speaker popping, quickly decided to replace the speakers with plans for an amplifier later.

2) Selected and ordered speakers with moderate power requirements knowing I didn't want to go crazy with this.

3) Ordered a JL XD300/1v2 amplifier for a subwoofer.

4) Replaced the rear speakers and realized the new ones didn't pop but sounded flat because the head unit isn't enough to drive them.

5) Returned the XD300/1v2 amplifier, having never even connected it, and ordered a JL XD700/5v2.

6) Ordered XTC 6 1/2" foam speaker baffles to give the door speakers better sound. Got the slimline but really didn't need to and should have used the full depth units for better sound.

7) Ordered Metra harnesses 70-2057 and 71-2107. Had to wait 34 days for the 71-2107 part to arrive. Ugh.

8) Installed all four door speakers and baffles while waiting for the harness. Clipped the speaker wires from the stock harness in each door and wired them to the speakers. You need a razor blade and patience to cut back the glued fabric wrap around the speaker wires.

* there are some videos showing how to deal with the interior door panels. I'll link those below.

9) Removed rear seats and all of the interior trim on each side from front to back. Expect to break a few trim retainer clips on rear most panels and then order those from the dealer because you can't get them elsewhere.

10) Moved the factory insulation from the back wall, passenger side, to clear a spot for the amplifier mount.

11) Cut a plastic cutting board to an appropriate size for my amp, wiring, and mounting bolts.

12) Drilled holes in the cutting board for mounting bolts. Added the bolts with a nut front and back to hold the bolt solid for glueing.

13) Used JB Quick (way faster than regular JB Weld) to glue the amp board to the back wall. Used bolts long enough to mount the board over top of the factory insulation. Checked clearance with the jack first. Used a 2x4 and foam pad against the front seat to press the amp board into place while the JB Quick set.

14) Removed the amp board and added more JB Quick around the bolts on the back wall to build up the glue'd area in hopes of the bolts not popping off later.

* I actually did this process twice because, the first time, I used bolts too short and, when mounting the board, did pull them off the back wall. The second time, I used longer bolts to allow more room behind the board for the insulation.

15) Ran power wire through the door/rocker channel on the passenger side, drilled a hole through the firewall and grommet after sanding/grinding the rough spots off.

16) Mounted a circuit breaker to a metal plate and bolted that to the support bar over the battery. Connected power wire from the empty position at the battery and ran that to the breaker. Connected the other side of the breaker to the wire going to the amp.

* removed the glove box thinking I'd find a place to drill but just found a butt load of HVAC so don't bother. Final drill location was selected by pulling back the carpet and going as high up as I could after also making sure I was inboard of the wheelwell and that nothing would be damaged in the engine bay when the bit poked through.

17) Ran the amplifier ground to the rear bolt of the jack bracket.

18) Ran RCA cables, Speedwire, and amplifier remote level wire in the driver side door/rocker channel to the front of the vehicle. The amplifier remote lead is using RJ-11 plugs with four wires. That's standard two line phone wire so if you don't have a long enough wire the RLC kit, you can get or make a longer wire easily.

* Its a tight fit to get all of the wiring into the factory plastic wiring trays that are under each sill plate but, it was possible.

* Brought the wires up by the emergency brake and zip tied them to another harness to make sure they don't obstruct anything.

* Rant the wires under the dash and over to the center of the dash using a coat hanger as a guide. Zip tied everything once it was in place.

19) Connected all wires at the amplifier.

20) Removed the dash trim and the the 8" display / HVAC control unit.

20) At the dash, soldiered the 70-2057 harness to the Speedwire to take the amplifier output and feed it into the stock speaker wire harness by the stereo. Heat shrink on each soldiered connection and then a larger piece over the bundle of eight wires to keep everything clean, organized, and snag free.

21) At the dash, cut the RCA ends off the four cables and soldiered the 71-2107 harness to these to feed factory audio output to the amplifier. The RCA cables had a tiny gauge positive wire in the center and then a braided negative around the outside of each channel. Dealing with the braided wire and then soldiering those was annoying but didn't actually take all that long. You could buy speaker wire to RCA adapters but I didn't want to add even more pieces or spend even more money. Heat shrink on each soldiered connection with a larger one over each +/- combo to clean up the outer braided / inner straight mess you'd have otherwise.

22) At the dash (eventually) mount the remote level control for the amp. For now, mine is in the small drawer where an ashtray would be if this were the 80's.

23) Adjusted input sensitivity on amplifer and tuned it.

24) Put everything back together.

25) Enjoyed bitchin new sound.

Tattooo · October 18, 2015

Damn thats a long ass post [emoji6]

Post some pics

Hozer · October 18, 2015

The amp rack. Plastic cutting board on bolts glued to the back wall. Once the bolts were secured, I removed the board, folded the factory insulation back into place and used a razor blade to cut holes the bolts could fit through. The board was mounted over top of the insulation and fits behind the seat. Great clearance with the seat down. A bit snug with the seat folded up.

Stock wiring with my new RCA cables (four in one bundle) and Speedwire coming up from below waiting to be spliced in.

Hozer · October 18, 2015

Harness in progress.

Hozer · October 18, 2015

Damn thats a long ass post [emoji6]

Post some pics

I should have added.... TL;DR: stock audio sucked, spent some money, hid some wires, don't tell my wife how much money was spent.

Hozer · October 18, 2015

Door panel removal (not my vid):

Tattooo · October 18, 2015

I should have added.... TL;DR: stock audio sucked, spent some money, hid some wires, don't tell my wife how much money was spent.

My lips are sealed [emoji52]

Hozer · October 18, 2015

I forgot to mention: Yes, the chimes are loud with the amplifier in. I didn't go crazy with the amp so they aren't ear splitting.

I may eventually feed the dash speakers from the front stock output and feed the front doors from the amplifier using the input signal from the rear doors. For now, I'm going to live it the loud chimes and see how bad they bug me.

Sadly, I drove the truck tonight and, when I came home and parked, my wife knew I was home because she heard the chimes from inside the house. It may be time for an exhaust upgrade!

Hozer · October 18, 2015

Pinout of the factory stereo output harness behind the dash:

ITEM WIRE COLOR LOCATION

Left Front Speaker (+/-) // blue - brown/blue // radio, green 16 pin plug, pins 1 - 9

Right Front Speaker (+/-) // yellow - yellow/black // radio, green 16 pin plug, pins 2 - 10

Left Rear Speaker (+/-) // green - green/black // radio, green 16 pin plug, pins 3 - 11

Right Rear Speaker (+/-) // white - blue/black // radio, green 16 pin plug, pins 4 - 12

Pins 5, 6, 7, 13, 14, 15 are not used.

Pins 8 and 16 are +/- power input for the stereo. If building a "T" harness like did, you directly connect pins 8 and 16 between the two new harness parts.

RobZ71LM7 · October 18, 2015

Nice writeup. I'm going to have to pick your brain. I'm looking to mount a 4-channel compact 50w rms X 4 amp under the dash to power aftermarket door speakers. I'm going to hold off on a sub for now.

Hozer · October 19, 2015

Here's the breaker mounted to a lightweight steel plate. 4 gauge wire from the battery to the breaker and then to the amp through a hole in the firewall down below. I don't like the angle of the output wire but, that's my only option given where the mounting bolts are on the breaker.

GRN69CHV · October 28, 2015

Nice writeup. I'm going to have to pick your brain. I'm looking to mount a 4-channel compact 50w rms X 4 amp under the dash to power aftermarket door speakers. I'm going to hold off on a sub for now.

http://www.gm-trucks.com/forums/topic/170685-line-level-amplifier-connection-help/

Inline amp is as easy as it gets. Mine sits behind the glove box, secured with a couple zip-ties. I use the rear channels to drive a pair of 8" Shallow mount subs (ran as full range woofers) mounted in the rear doors. Front and dash speakers are still factory items. Huge improvement.

Hozer · November 8, 2015

Well, for a truck I hardly drive, that sure didn't take long to blow the factory dash speakers now that they're amplified. Guess I'll pick something out this week and make that swap soon. I'm going to try and stick with a full range speaker up there rather than just a tweeter if I can find something I like. Mounting a 3.5" full range (coaxial w/ separate tweeter most likely) will take a little modification but shouldn't be too bad.

Currently looking for a good deal on the, now discontinued, JL Audio Cleansweep in order to clean up the overall sound a bit and get rid of the horrid factory equalization.

Hozer · November 13, 2015

Well, the dash speakers have now been replaced with a set of Infinity Reference 3002cfx full range coaxials. That is probably not the speaker to be used in the dash of these trucks.

The stock speakers are 2.75" diameter but also have a rather small magnet. The Infinity are 3.5" diameter with a magnet nearly that size and also quite thick. I was expecting to do some plastic removal to enlarge the holes and make the speakers fit and that worked okay on the driver's side but the passenger side is another story.

On the passenger side, the dash HVAC duct runs in front of and somewhat under the speaker mounting hole. Enlarging the mounting hole still doesn't let the speaker fit because the duct is blocking the magnet from fitting down in. I had to cut away a piece of dash plastic on the right front side to get the speaker mounted in.

On both sides, I also needed to use a Dremel to grind some plastic from the under side of the dash speaker grills to keep the speakers from impacting the grill. That part was actually easy and straight forward.

The new speakers sound much better but, in hind sight, just mounting a set of tweeters in a fabricated plate to fill the hole would be far easier than cutting away to fit a set of full range speakers in.

I took a few pictures, I'll post them up tomorrow.