Line Level Amplifier Connection Help

Hozer · June 20, 2015

This thread has been a big help. I'm in the planning stages of audio upgrades in my '14 Sierra CC, non-Bose, and it's nice to know about the wiring, chime source, etc before opening anything up. I'll be ordering those Metra 71-2107 and 70-2057 harnesses to create one I can use for feeding amplifier inputs and then feeding the amp output directly back into the stock speaker wiring. I'd started trying to find the right parts and you've all saved me a lot of time! Thanks for doing the research on those!

I was really hoping the chimes were going to the driver's dash speaker via a separate source tapped to the wires to avoid amplifying it but, no luck I guess.

Can anyone confirm how the front speakers are wired? Does the HU have a six channel output (left rear, left front, left dash, right rear, right front, right dash) or just four channel (left rear, left front, right rear, right front) and then split the front outputs to feed the dash speakers? If it's six channel, I'd be happy to leave the factory feed to the left dash for chimes and use the front door feeds to the amp and then crossovers to feed the aftermarket speakers.

My main objective is to add a good subwoofer and retain the factory head unit.

So far, my plans are for either a JL 10TW3-4 or 12TW3-4 along with a JL XD700/5 amplifier. Likely going with Infinity Kappa 60.9cs in the front and Infinity Reference 6032cf in the rear doors. I thought about leaving the stock speakers but figured that once I use the rear speaker leads as source input for the amp/subwoofer, I'd want to feed those via an amp rather than just splitting the feed from the HU. The XD700/5 amp is pretty well priced for being able to run all five channels pretty clean so, in for a penny, in for a pound.

Provided that my wife doesn't learn the total cost of the system, all should be well when it's done and installed.

Hozer · June 20, 2015

I'm now pretty sure the front door and dash speakers are fed via a single output (per side) from the HU. I can hear the chimes through both the left door and left dash. I tried the chime audio level setting and, while it does make some difference, it's certainly not much.

GRN69CHV · June 21, 2015

4 channel output. Dash speakers split off the front left. Have two choices, #1: Install a lower power amp and run minimal gain (this is what I did, Alpine 445 is 45w/channel and adds more than enough power to make the system come alive) and just deal with the increase in chime volume or #2: Reroute the front doors speakers to receive the rear door speakers signal effectively eliminating chimes and voice from the doors completely, this would allow you to run the dash speakers strictly off the HU.

Hozer · September 13, 2015

4 channel output. Dash speakers split off the front left. Have two choices, #1: Install a lower power amp and run minimal gain (this is what I did, Alpine 445 is 45w/channel and adds more than enough power to make the system come alive) and just deal with the increase in chime volume or #2: Reroute the front doors speakers to receive the rear door speakers signal effectively eliminating chimes and voice from the doors completely, this would allow you to run the dash speakers strictly off the HU.

I like the harness you built to avoid cutting factory wiring. Can you confirm whether you have the non-Bose system? I want to order the parts but have the non-Bose system and need to be sure those harness parts will work.

I'm finally getting parts together for the install and was thinking perhaps I'd leave run new speakers off the factory head unit but, after installing new rear speakers and being entirely underwhelmed by the improvement, I've opted to proceed with amplifying the speakers and not just a sub.

I'll be taking your suggestion of running the dash speakers off the head unit only and using their normal front feed.

For the front and rear door speakers, I'll feed them from the head units rear feed run through an amplifier.

GRN69CHV · September 13, 2015

Yes, mine is the non-Bose with 8" touch screen. FYI, I still have the stock front door and dash speakers, these are both ran off the front channel through the Alpine 445 amp. high pass filter set to 80hz cut off. Rear door speakers are the 8" Earthquake shallow subs run off the rear channel, ran as full range speakers. 8's were an easy enough install. Took a little trimming to the inner door skin and door panel to fit, but worth the effort. 6.5's would fit right in.

PS - take the time to add sound dampener to the outer and inner skin. Well worth the effort, especially with an amplified system.

Hozer · September 13, 2015

Did you connect your new harness behind the head unit or down by the hood release? I'm assuming there's a factory harness with the same plugs are used on both ends that goes from the head unit down to the wiring block by the hood release which then breaks out to other harnesses to feed individual speakers.

GRN69CHV · September 14, 2015

One harness has a male end, the other a female end. Plug one into the head unit, the other into the factory wiring. I buried the Alpine 445 behind the glove box. I'm assuming you are going to mount your amp behind the rear seat for the sub? Might be easier to just run your leads down the passenger side.

Hozer · September 14, 2015

Yeah, going to mount a JL Audio XD700/5v2 behind the rear seat if possible. If I don't feel okay about the cooling back there, I'll mount it on the floor under the rear seat right next to a subwoofer.

My plan so far is to build a custom harness and connect side A of it to the output behind the head unit. The rear speaker outputs from the head unit, now in the new harness, will be spliced to RCA cables feeding back to the amplifier's input. The amp supports high level input so I shouldn't need any line output converter. I'm going to run Stinger Speedwire (9 wire) from the amplifier's outputs back up to the head unit location and splice those into side B of the new harness thus feeding the front and rear speakers from the amplifier. For the dash speakers, I'll need to split them from the front door wiring and run new wires up to harness side A so they receive the front speaker signal from the stock head unit.

This will be a lot of work up front and I'm spending a lot on wiring components but, I did order most parts this weekend and should be ripping things apart next weekend. If my wife finds out what I'm spending on audio, she'll be ripping me apart but I've got hopes that she'll be forgiving.

JimmyJ_123 · September 15, 2015

Hoser, That makes me laugh. Im the same way. 2 sets of 6in component Diamond Audio, 1 set JL Audio C5 650. Diamond 10 in sub. MMats Amp for the sub. Just bought the JL XD 600/6v2 to push the speakers. with a LCQ1 line converter. If my wife new how much it all cost. I would be sleeping in the truck bed. Should sound great !!

GRN69CHV · September 15, 2015

[Yeah, going to mount a JL Audio XD700/5v2 behind the rear seat if possible. If I don't feel okay about the cooling back there, I'll mount it on the floor under the rear seat right next to a subwoofer.

My plan so far is to build a custom harness and connect side A of it to the output behind the head unit. The rear speaker outputs from the head unit, now in the new harness, will be spliced to RCA cables feeding back to the amplifier's input. The amp supports high level input so I shouldn't need any line output converter. I'm going to run Stinger Speedwire (9 wire) from the amplifier's outputs back up to the head unit location and splice those into side B of the new harness thus feeding the front and rear speakers from the amplifier. For the dash speakers, I'll need to split them from the front door wiring and run new wires up to harness side A so they receive the front speaker signal from the stock head unit.

This will be a lot of work up front and I'm spending a lot on wiring components but, I did order most parts this weekend and should be ripping things apart next weekend. If my wife finds out what I'm spending on audio, she'll be ripping me apart but I've got hopes that she'll be forgiving.]

For what you are doing, there's really no need for the harness adapters. Running the Speedwire back to the factory harness, you will still have to trace the left front speaker lead, cut and splice it, then run a separate wires back to the harness and head unit if you want to eliminate amplified chimes, etc to the dash speaker. I think what you are planning is defeating the purpose of adding a 5 channel amp into the system. You;d be better off, not using the harness adapters, just tap into the rear channel leads off the head unit (don't even need to cut the factory harness, just peel wiring casing back. Run one set of leads back to the amp then new speaker wires to the doors and sub. FWIW, amplified chimes is really not a problem an lower gain settings, keeping the front door speaker connected to the front also keeps the phone voice coming from both the dash and the door, other wise, your phone calls will only come through the tiny dash speaker. Might be ok, but I'd think it might be kinda tinny.

JMHO, if you don't want to run new wiring to the doors, then consider using the harness adapters you bought, adding an in-line amp (Alpine 445U works great) to power the doors/dash, then run one pair speaker wires back to a simple 2 channel (or even 1 channel) dedicated sub amp. Alpine 445U can be ran right off the factory radio hot lead (have had mine connected for 7 months now). At 50% level on HU and gain on amp set to about 30% it gets very loud in the truck. Keep in mind, I'm still running factory front door/dash speakers (front set to 80Hz high pass filter to cut off the bottom creates a lot more clear volume with less power ); a pair of 8" shallow mount subs (ran as full range speakers) in the rear doors. all powered off the single 445U compact amp.

Fasthotrod · September 15, 2015

Yeah, going to mount a JL Audio XD700/5v2 behind the rear seat if possible.

My plan so far is to build a custom harness and connect side A of it to the output behind the head unit. The rear speaker outputs from the head unit, now in the new harness, will be spliced to RCA cables feeding back to the amplifier's input. The amp supports high level input so I shouldn't need any line output converter.

I was able to put three JBL MS series amps and a JBL MS-8 behind the rear seat of my Quad Cab. The amps are 8-13/16"L x 7-1/4"W x 2-13/16"H, and I mounted them on a rack made of angle iron and 3/4" MDF. (It's 3 9/16" thick, but with carpet it 's closer to 3 13/16" thick.)

Build log is here: http://www.diymobileaudio.com/forum/build-logs-project-install-gallery/162172-2014-silverado-crew-cab-z71-ltz.html

The amps are fine when the seats are down, but when you fold up the bottom cushion the back of the seat tilts towards the back wall and hits one of the amps. If I had to do it all over again, I'd use thinner MDF or a different material completely.

The JL Audio XD700 is 10-1/4"W x 2-1/16"H x 7-1/8"D so you should be good to go. I found it to be much easier to just use a vampire tap on the rear speaker leads in the b-pillar. I show some pictures of the plugs in my build log.

If anyone wants a really good sub amp, the JBL MS-A5001 is a decent amp in a small package. I paid quite a bit more than the $149 that they are going for today. They put out well over their advertised specifications, have a built in crossover, both low and high level inputs, etc...

You can get them for $149 here: http://www.newegg.com/Product/Product.aspx?Item=9SIA1D914D2449&nm_mc=KNC-GoogleMKP-PC&cm_mmc=KNC-GoogleMKP-PC-_-pla-_-Car+Amplifiers-_-9SIA1D914D2449&gclid=CO6q-IbL-ccCFQaPaQods48PgA&gclsrc=aw.ds

...or here: http://www.sonicelectronix.com/item_29472_JBL-MS-A5001.html?%3futm_source=google&utm_medium=paid_search&utm_campaign=sc_ps_google&scid=scawd9347851&gclid=CLHn-fPL-ccCFQuLaQodcaQEmw

Inspiration for my build came from this install... this is very slick: http://www.diymobileaudio.com/forum/build-logs-project-install-gallery/159994-2014-chevy-silverado-musicar-northwest.html

Hope this helps.

Mark

Hozer · September 17, 2015

Fasthotrod - you're build log has been a big part of my planning but, I'll be doing nothing anywhere near that sweet.

I'm trying to keep to relatively inexpensive components, at least compared to what I'd LIKE to do but, I'm also forking out money to do things as cleanly as possible.

I would like to have re-used a 10" Orion HCCA that was in my 2003 Silverado extended cab but that subwoofer is FAR too deep to use in the my '14 Sierra. Instead, I'll be picking up either a JL 10TW3 or 12TW3 in an JL truck wedge box since either fits under the seat well and, while I've built several boxes in the past, finish work isn't my thing so a prefab that fits just right sounds nice.

For now, I will be using my HCCA subwoofer though at half the power its used to from the Orion HCCA 250 (internals upgraded to the 275) of the past.

Amplifier: JL XD700/5v1

Rear Door Speakers: Infinity Reference 6032cf

Front Door Speakers: Infinity Kappa 62.9i

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

Subwoofer: JL 10TW-d4 or 12TW3-d4

Head Unit: Stock

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

Equalizer: None for now; AudioControl LCQ-1 later on if I'm not happy with the response from the stock head unit feed.

Wiring plans:

Using Metra harness 71-2107 and 70-2057, build a custom T-Harness. "Left" side is output to stock speaker wires. "Right" side is input from head unit.

* head unit +/- Direct connect between the left and right side of the T to pass directly through as stock

* front speaker output Cut the "Y" on each side of the front to seperate the doors from dash. Run new wire from dash to the harness behind the head unit.

Pass signal from factory harness to the new dash wires

* rear speaker output Send signal from the "right" side to a new set of RCA cables which run to the amplifier input. RCA cables will have ends removed on one side and soldiered to the harness wires.

* front door speaker input Pass signal from amplifier front output to the front speaker position of the "left" side of the harness. Use factory wiring from harness to door speakers.

* rear door speaker input Pass signal from amplifier rear output to the rear speaker position of the "left" side of the harness. Use factory wiring from harness to door speakers.

Amplifier to be wired with 4 guage KnuKonceptz Kolassas Cable. Inline fuse near the battery. Not sure yet if I'll go through the firewall and along the door sill channel or go under the vehicle and through the floor. Body to battery ground to be upgrade to 4 gauge. Battery post to battery distribution block to be upgrade to 4 gauge.

The complicated setup of the front speakers may end up being a moot point. I'll test the volume of the door chimes with the front signal amplified and, if its not too bad, I'll just amplify the fronts using the proper input signal.

If I can find a secret code to disable the door chimes, I'll go that route and be 100% happy. I wear a seat belt every time and make passengers do the same. I don't need the truck assaulting my ear drums because I've touched the gear shift before everyone finished buckling.

Hozer · October 18, 2015

It's been WAY too long but, I finally finished up most of the install today! The harnesses previously mentioned and the audio pin outs were a big help with the wiring. I'll throw my build into a separate thread but do want to say thank you to everyone who's put good info up on this board. The pictures, part numbers, and explanations here were invaluable!

mois93da · October 28, 2015

Any word on the chime issue?

I'm considering a five channel amp setup but not till I ruin the factory speakers. I will be keeping the factory mylink touchscreen w/o Bose.

Hozer · October 29, 2015

The chimes are definitely loud. Same goes for the turn signal though, because that is a lower frequency sound, it's not nearly as annoying. I'm still thinking about splitting my front speakers to run the dash non-amplified from the head unit front signal and doors amplified from the head unit rear signal.

Presently, I'm hung up on the overall lack of audio quality due to the factory head unit being tuned (non accessible EQ settings) to work with the stock speakers. There's a noticeable lack of response in the ~80 to ~200 Hz range plus whatever I can't hear and identify.