Audio help needed

ageless1

Active Member
I posted this "article" on Crutchfield's forum; If anyone has ideas or info, please chime in. This information will be invaluable to anyone looking to upgrade their factory sound and I will share whatever I learn.

"I'll start off by telling you what I have and what I am looking to achieve. I have a 2014 Mustang with a base (4 speaker) stereo. I am wanting to add some moderately high sound quality. The two most important things are to use the factory HU and the factory wiring for the speakers, keep the SYNC function and to not cut any factory wires in the harness. I have already added the door speakers (Rockford Fosgate Punch 6X8's) and there was a remarkable difference. I have already acquired an amp (Polk PA660 A/B) and will be looking to integrate this. I am undecided about what to do with the rear deck speakers, at this time, due to the extensive labor involved in accessing them. I will also be looking to install a sub-woofer; specifics are still up in the air on that.

Since the car is new, nobody seems to have the updated information as to what exactly fits. I believe this model shares the same HU as 2011 and up but am not exactly sure. I also believe that the upgraded (SHAKER) system uses the same HU as the base system. Again, this is only speculation. My first question is about the factory head unit. I noticed that there are two "amp" harness slots on the back of (a 2013) the factory head unit. This I believe would be the equivalent to most after-market pre-amp out/in's, one is the output (conceivably this is a low level signal) The reason I think so is because in doing exhaustive searching for harness kits, I have seen the actual replacement which includes 16 feet of wire; this harness is for the Shaker system. Alternately, I see an amp bypass harness that basically connects the two with about 4 inches of wire. Additionally, I have seen (just not for my specific vehicle) plug-in's that convert similar wiring harness' into RCA's. What I think is going on here is that Ford's OEM amp is wired just like any other car amplifier, but they just run straight wires with a low-level signal. If that is the case, would this be the same low-level signal that is used by the RCA cables? If it is, then that should eliminate the need to use LOC's?

I have read an older post that had someone trying to accomplish the same thing that I am, however, I wanted to get a little more clarity on the subject of the factory amp set-up. Is there some secret, non-standard signal that only Ford and the manufacturer of their Shaker amp are privy to? I'm thinking not. What I am thinking will streamline the installation and ultimately save time, space and money (all of which are lacking in my case) is to get the "factory amp" harness that converts to RCA- Run them to the Low-level input in the amp- Then RCA back to the HU with the amplified signal through another RCA converted harness and be done... or am I? One thing that bothers me is that I really don't know how the signal gets from my "idea" back to the speaker wires plugged into the main wiring harness. Will I blow up my HU with 75 Watts RMS X4? I think the factory amp is something between 30 and 45 RMS. Maybe the signal is just wired into the speaker wires internally without going through any kind of circuitry? Not sure on this part.

Another thing I am looking for answers on involves amp location, RCA needs and shielding. Ideally, I want to mount my amp in the "best" location. I have three spots in mind. Under the passenger seat, attached to a rear seat back or hanging from the parcel shelf in the trunk. Knowing that shorter cable runs are ideal, what would be better, shorter RCA cables or a shorter 8 gauge power cable? What kind of RCA cables will I really need? I've seen at least 8 different categories on these. O2 free, braided, twisted, single sheath, 2-way, 4-way, standard... back in my day, the only thing you had to choose from was 6 ft or 25 foot... will getting a fancy cable really make a difference while driving? Will it substantially reduce the chance for needing ground loop isolators?

The PA660 has speaker level inputs as well. Originally, I had planned on adding this amp to the 4 ch existing setup but with the uncertainty about the rear speakers, I opened up to some other ideas. 1- Wire the amp for 4 channel setup and keep the old speakers where they're at and hopefully wont blow them (Factory speakers have 25W stamped on them), while adding a sub system at a later time using speaker level input off the rears. Q- Will the higher powered speakers with 75watts RMS running though them affect how speaker level inputs perform? Is that too much power? Would I need to revert the rear speakers back to factory power before tapping into them? Does it depend on what amp is used for the sub; being either something like an Infinity Bass Link or a custom set-up? 2- wire the amp for 2.1, bridging the rear channels to power a sub. This would pose a question of whether or not having rear speakers would make much of a difference. 3- 4 channel amp config. and Run some Mid-Bass drivers 5X7 in the rear deck instead of full range (many forums shun this idea, but then again these are the same guys that think 100% coverage with three layers of dynomat extreme is the only way to dampen sound) What kind of "punch" can I expect to feel out of 2 5X7 mid bass drivers anyways? could it be enough to not have to add a sub or not have to have a pair of 10-12" drivers in the trunk? I don't consider myself a bass head. I just like to feel my music. The configurations and options are endless, I know, and it comes down to what is in my budget... I am just trying to maximize here.

I have plenty more questions, but I think I need to get the above part ironed out before I even consider them. I appreciate any insight into getting me hooked up."
 

ageless1

Active Member
Ill read that in the morning. Or maybe you can condense it some.

What?! This is the condensed version! lol

Basically, I'm trying to keep the factory look/functions but make it sound kick ass while spending as little as possible.
 

ageless1

Active Member
The condensed conclusion: I'll be integrating an amp, 10" powered sub, and new door speakers. I will likely be installing it on Friday, since I am supposed to have everything in by Thursday. Details to follow. for now, I wait...
 

13v6

Member
Ageless, I wish you all the best and will be waiting to read about what you decide and do. One thought, have you thought about using 6x9 speakers in the back. There's a nice adapter that will accomplish this and there's plenty of room in the trunk. Well, that's one of my ideas to do, anyway.
 

ageless1

Active Member
I'm not sure if you've read the linked post or not but the short answer is yes. I haven't fully researched it yet though. I was hoping someone has and would post their findings here.
 

ageless1

Active Member
At any rate, here's my thoughts on putting 6X9's on the parcel shelf: The speaker holes on the parcel shelf are pretty small and will only accommodate 5X7 speakers when using the original factory designed top-mounted set-up or, with the help of an adapter ring, 5.25 round speakers. From what I know, one could fabricate a larger adapter to accommodate a larger speaker (such as a true 6X8, 6X9 or even a 6.5" driver) but you would then be required to cut holes in the dash covr and install grills. Personally, I don't find that to be to terrible of a deterrent or too difficult a task to accomplish, however, it would detract from the OEM or factory look. One of the reasons that I want to maintain the factory look is that I don't want to advertise to any would-be thieves that I have anything of value to steal. I have had a couple of break-ins over the course of my life and invariably, the damage that the thieves did while breaking in far exceeded the value of the items stolen.

One of the ideas I had involved re-configuring the OEM mounting style from top-mount to bottom-mount. Anybody that has either replaced the rear speakers or looked into it (for the L197) has likely learned that it is quite a PITA and usually states that they probably wouldn't do it again because it just isn't worth the trouble for such a minimal gain in sound quality. The reason is because the rear speakers do little more than add "fill" sound. I really will not know for sure until I get in there and start pulling things out myself since there is so little information on it. Hopefully, I will be able to document it and post it here for those wanting information on it. There are some YouTube videos of people getting to the rear shelf via tearing out nearly the entire back interior, I am trying to avoid that, besides, according to Crutchfield, much of that can be avoided with a little finesse... we shall see.

Back to my idea on the bottom mounted rear speakers- I can see that the speakers are screwed into some little plastic retainers that are attached to the metal shelf. If possible, I would like to remove the retainers and put them either back on upside down or use a metal clip-on style that usually comes with new speakers. As of now, I don't know if there will be any clearance issues between the parcel cover and the actual shelf (regarding how much screw protruded out the top) but I clearly remember doing a car that had factory speakers flush with the cover and the speakers were supposed to be drop-ins (according to Crutchfield) but were not flush. The tweeters were about a quarter inch higher, resulting in an ill-fitting cover.

Once I am able to engineer a cheap way to make these a bottom mount speaker, I will then have questions regarding how sound would be affected. Adhering to my OEM standards would prohibit me from cutting any metal away from the parcel shelf to make bigger holes for bigger speakers so, to what extent would the sound coming out of, say, a 6x9 be changed, bottom mounted to a 5x7 hole, providing I could accomplish this? Also, I have seen (pictures) of replacement or custom parcel shelves for older cars, not so much for newer cars. Are these shelves integrated into the body? Easily, swapped out (if not part of the body's structure)?

While writing this I wanted to attach pics showing some of the stuff I am talking about and came across this post on another forum. I am new to forums so if it is a faux pas, I apologize.
 

ageless1

Active Member
Have you seen these adapters? You can mount 6x9 speakers to the 5x8 holes. No deck modifications needed and only $8.99.
Xscorpion SP-AD6957 6"x9" to 5"x7" or 6"x8" Speaker Adapter

In order for those to work, you would need to cut holes in the rear parcel shelf cover; I'm pretty sure the speakers are relatively flush mounted, however, If you get the chance to remove them, I don't see any reason why you wouldn't be able to do the bottom mount deal I talked about before. I have just finished installing my amp and sub and don't think I ever want to do that much work again, LOL! I'll be posting the details of it soon. If I ever have to remove the rear panels again, I will end up doing it, but as it stands now, I am content with not doing that again. Great find BTW!
 

13v6

Member
Why would you need to cut any holes? They mount directly to the deck with the (sorry) 6x8 holes. They then will adapt out to fit the 6x9 speader on the other side of the adapter. What are the new holes for?
 

ageless1

Active Member
Why would you need to cut any holes? They mount directly to the deck with the (sorry) 6x8 holes. They then will adapt out to fit the 6x9 speader on the other side of the adapter. What are the new holes for?
I am not 100% sure about the 2013 but on my 2014, this is what you'll find after removing the rear deck cover:
image.jpg


This is what it will look like with the cover (carpet glued to fiber board) removed. The cover is mounted flush to the deck so when you go to put the cover back on, it won't fit; because the brackets raise the speaker mounting surface up about an inch. The hole size is 5x7 not 5x7/6x8. most speakers advertising 6x8 are actually 5x7. how do you tell? if it says "also fits 5x7" it's a 5x7. I only trust Crutchfield to find what speakers actually fit specific applications. If you check, you'll find that the fronts can fit some true 6x8 speakers (usually with minor modifications) but the rear speakers have far fewer choices and they are limited to 5x7 and smaller. The new holes I refer to would be the new 6x9 holes you'd have to cut in the carpeted cover and then attach grills to cover the speakers.
 

13v6

Member
That's what the adapters are for. They mount to the existing holes and go under the deck , sticking DOWN into the truck. Then the 6x9s mount UNDER them. Nothing is sticking up above the deck. In your mind, turn the adapter over so the large part is on the bottom, not the top. I don't see why that wouldn't work.
 

ageless1

Active Member
See post #8. But yes, that is what I meant all along. I was simply reiterating the point that the whole top mount design is just totally crappy in all regards. At any rate, it's not worth taking apart my car more than once. At least at this point... hindsight is a bitch! Lol
 
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