Validate my shopping cart for updated audio system?

[DavidZemon]

That helps A LOT. I had started to piece all of that together through previous replies, but the wiring diagram sure clears it up.

The crossover to eliminate high frequencies going to the door speakers - that must be an integral part of the OEM amp, right?

[LimitedSlip]

Originally Posted by DavidZemon

The crossover to eliminate high frequencies going to the door speakers - that must be an integral part of the OEM amp, right?

The short answer is "yes". That amp has been a bit of a puzzle but this thread will provide more info than you probably want:

https://www.ft86club.com/forums/show...39#post3436339

[FR-S2GT86]

Originally Posted by LimitedSlip

The following diagram shows how the dash and door speakers are wired. The dash tweeter and mid-range speakers are both 4 ohms. These two speakers are also essentially wired in parallel with the input to the trunk amp. Together, this presents a 2 ohm load to the HU (assuming the input impedance of the trunk amp is somewhat higher than 4 ohms - which is likely). So, the HU front speaker outputs are driving all six speakers with an amp between the head unit and the door speakers. This means that with factory wiring, whatever adjustments (tone, balance, delay, etc.) that you apply to the front HU output will be applied to all six speakers (Not ideal). If you want to deal with the dash and door speakers individually the best approach would be to run new wiring from the HU to the doors thus bypassing the factory amp in the trunk (FYI: Running new door wires is a bit of a challenge).

The rear side panel speakers are driven separately, directly from the HU and are identical to the dash midrange units with two exceptions:
1. The mounting brackets.
2. The fronts have an additional low-pass filter capacitor to block the high frequencies that the tweeters should handle.


(Thanks to @MugsBRZ for the speaker pictures.)

Actually, those capacitors on the dash OEM mid-range drivers are acting as HIGH-PASS filters to filter out LOW frequencies at about 4kHz @ 6db/octave. This is so the mid-range drivers aren't overdriven into distortion by attempting to play frequencies that the OEM door speakers were intended to.

Those OEM mid-range drivers should naturally roll off around the same frequency that the tweeters are designed to begin playing sound. The high-pass filters for the tweeters are rated at about 14.7 kHz @ 6db/octave.

Also, when you have separates in your system, they are normally rated as a set. For instance: a 4-ohm tweeter matched to a 4-ohm woofer in a matched set is rated at 4-ohms. The filters are what keep the set of speakers' impedance value at 4 ohms. To further explain this, if you had a 4-ohm 6" driver in parallel with another 4-ohm 6" driver with no filtration to act as a crossover for this set, you would have a 2-ohm load....on the other hand, if you were to add a high-pass filter at....let's say.... 5kHz to the first speaker, and a low-pass filter to the second speaker also at 5kHz, then that set would be rated at 4 ohms because the first speaker can't play much above the crossover point of 5kHz, and the other speaker can't play much below the crossover point of 5kHz. This would result in the total impedance value of the set to be 4 ohms.

[DavidZemon]

Originally Posted by LimitedSlip

The short answer is "yes". That amp has been a bit of a puzzle but this thread will provide more info than you probably want:

https://www.ft86club.com/forums/show...39#post3436339

Actually, that was great info I had no idea this deep dive in the factory amp was so recent. I had assumed the audiophiles around here would have done this back in 2012 or 2013 :P.

[FR-S2GT86]

Originally Posted by DavidZemon

Actually, that was great info I had no idea this deep dive in the factory amp was so recent. I had assumed the audiophiles around here would have done this back in 2012 or 2013 :P.

I just got curious about it one day when I had more time to research these things. Not so much anymore since I've changed careers.

[soilent]

So to go back to the original question, I think you should stick with your Rockford component set and get these things instead. I'm assuming you want to go with that headunit because it has Apple car play, but if that is not extremely important I would actually leave the stock head unit and just buy a DSP and amp. I recommend these items:

Amp for mids and tweeters.
https://www.sonicelectronix.com/item...RZ4-1200D.html

Adapters for tweeters. They will go in the 3.5" space in your dash. You already had mid adapters on the list so you're good on that. https://www.amazon.com/gp/product/B0...A1LAPRHCR7XHF0

A DSP for controlling speaker level, EQ, and crossovers. This Dayton unit will act as a high level converter and has 6 channels incase you want to add a sub. https://www.amazon.com/Dayton-Audio-...s%2C354&sr=8-2

If you don't plan on running a sub, MiniDSP is always a good option too and a little bit cheaper, keep in mind you will have to run a high level converter or LOC for this. https://www.amazon.com/miniDSP-2x4/d...s%2C117&sr=8-2

And just a personal suggestion, if you decided to ditch the HU you'll be able to spend a little more on speakers. So I would recommend these over the Rockfords for just a little bit more. Alpine Type S.
https://www.amazon.com/Alpine-S-S65C...s%2C165&sr=8-4

You can use this guide to tap into the factory wiring and run power to the doors. You will need to run power directly from your amp to the tweeters though.
https://www.ft86club.com/forums/showthread.php?t=42239

Good luck!

[soundman98]

Originally Posted by soilent

Yes it does and it's absolutely terrible. It's in the trunk under the foam right behind the back seats. If you're not an audiophile, the stock speakers actually not bad, they just severely lack power. Your best bet is to just get some 6.5" component speakers, ditch everything in the dash, put the tweeter with an adapter in the 3.5" spot, and just don't worry about the rears at all. You won't hear them while driving and it's not really worth going through the hassle of wiring them.

Search for the "How to use oem wiring to add an amp" or whatever that thread is. You'll be able to use that repinned harness to run power to your door speakers (via an aftermarket amp). The tweeters you will have to wire your self from the amp up to the dash, but don't worry, it's not that difficult. Easier than running speaker wire to the doors, that's for sure. The only other thing you might need is a decent headunit (the one you listed seems nice, but doesn't seem to have crossover capability, correct me if I'm wrong) or a DSP (miniDSP, Dayton 408) so you can control the speaker level and crossovers. You can run passive crossovers that come with the component kits, but they usually kind of suck IMO and almost always make the tweeters too loud. It's best to run them actively.

You can also try the Toyota OE series kit from Powerbass. From what I understand it should fit our cars, even though it's not listed as such, and it's completely plug n play. The only issue is this will basically just be a speaker only upgrade and you may find yourself having the same underpowering issues.

Outside of that, if you're willing to take a day or two and run a few wires, the tweeter replacement and/or component setup with an amp will definitely do you right. I bought a component set for my old car and ended up just using the tweeters because I was satisfied with the door speakers after they were powered. I was also running a sub too, so keep that in mind. The door speakers won't be bass monsters, but do pretty well above 80hz.

i think it's important to re-read the very first line of the OP's first post.

Originally Posted by DavidZemon

Let me preface this with: I'm not an audiophile - I just bought this car to race SSC. But... the sound system is complete garbage. AM radio / bad record player garbage. And that head unit... frustrating as all get out (right-end of the screen is non-responsive).

i've got no problem spending other people's money. the installs are easier, and not getting that bill in the mail later is awesome.

but i don't think that a full-on audio install with a bunch of extra wiring and a DSP that needs programming is really what's necessary here for a street-driven race car.

it's completely up to davidzemon, but the K.I.S.S. method, and lack of in-depth audio interest is specifically why i recommended the HU first, and potentially the amp bypass (this would get rid of the filtering of the oem amp, which stands to make the door speakers work a little more to clear up the audio spectrum). i respect his thought process and willingness to 'just get it over with' and spend big enough to replace all of it, but feature-creep recommendations are real, and i don't get the impression that david is the kind of guy to fantasize over playing with 12db/oct and 18 db/oct slopes, or tweaking driver phasing for soundstage improvements like you or me.

Originally Posted by DavidZemon

Actually, that was great info I had no idea this deep dive in the factory amp was so recent. I had assumed the audiophiles around here would have done this back in 2012 or 2013 :P.

the short answer is that keeping it as part of an aftermarket system is more work than it's worth. once one commits to installing their own sub amp(which most audio guy's are going to do anyways), a new fullrange speaker amp isn't that much harder, and the benefits of adjustment that most of us crave to suit our own impulses of system design are too hard to ignore.

the more technical answer is because it doesn't have adjustable levels, isn't very powerful to begin with in aftermarket terms, uses speaker-level inputs instead of the more preferable low-level inputs of aftermarket gear, and makes the door speakers into subwoofers via integrated filtering that lack external adjustment. the deep dive thread into it was hoping to clear some of that up, but as you can see, we mostly got stuck at the filtering aspect. with more experimentation, it's possible that one might be able to manipulate the amp's audio filters to work better, but that's only 1 negative attribute in a much longer list, a list that any aftermarket amp easily overcomes with simple external industry-standard adjustable features.

[soilent]

Originally Posted by soundman98

i think it's important to re-read the very first line of the OP's first post.

And I think it's important to read the rest of OP's post where he has a laundry list of parts and adapters to get the job done. He also states he's not scared of wiring and soldering. He sounds pretty capable to me, and I gave him advice and a setup that I think would much easier suit his needs. He's already done enough research to understand just about every part he needs for this build. I don't think another 10 mins of Googling crossover points will kill him. No one said he had to learn all the ts parameters and proper times alignments. The things I'm suggesting are even cheaper and easier than what he originally planned to do. He can just grab a component set, high pass them at 80hz and cross them at 3k hz with a DSP/HU and amp and be on his way. It's really not rocket surgery and I think he will be more than satisfied with the results.



OP feel free to message me directly if you have any questions. I got you brother.

[DavidZemon]

Thank you all for the great feedback. You both have good points. For a bit more clarity:

Spec'ing out parts and performing mechanical-based installations are well within my wheeelhouse. I'm a car guy and computer guy, so _that_ is easy.
But I'm also pretty well tone deaf, so the idea of tweaking the phase of a speaker or measuring anything in "db/oct" is, quite literally, laughable to me. I'm glad you guys have ears and musical backgrounds fine enough to hear and appreciate those kinds of differences... but I don't. I can't even hear the difference between a 192kbps MP3 and a CD on a quality home stereo.

I installed the Sony HU Christmas eve and went for a few drives with it. The audio quality still isn't _great_, but I think it might well be "good enough." Just having a usable head unit has drastically changed my outlook. I will probably keep this for a few months (because it will hardly be driven in this cold weather) and re-evaluate over Spring or Summer.

One last question before this thread gets buried for a bit: is the old, stock HU worth anything? I'm guessing it's just ewaste, especially since the right-part of the screen (1/2" to 1") is unresponsive, but I'd certainly be happy to post it for free somewhere if there's actually a market.

[soundman98]

glad to hear about the head unit. if you haven't already, play with the different baked-in eq settings, sometimes they're enough to make everything work.

another simple/cheap option would be to build the amp bypass harness. some of the muddiness of the sound is due to the dash speakers picking up around 3-5khz, and the door speakers only working as 100hz-and-lower subwoofers. so by installing the bypass, it would make the door speakers play all frequencies, which stands to clear up the audio signal.



no, the factory unit, especially one that isn't working right is all but worthless to most people. ebay sold head units show an outlier at $250, but most being sold between $40 and $150 for properly working units.