shakinrock

In my opinion (based on my ears and my preferences) the biggest issue I have with my audio system is base DETAIL. The bass is there in volume but the detail is severely lacking. In low loud base notes its hard to be sure exactly what instrument is playing. You may disagree but that is NOT the purpose of this thread.

I have a '15 vert, 2lt, Z51. I want to take baby steps at sound improvements. My question is with respect to the two speakers behind each seat. What are they? Are they full range, woofer, sub woofer, etc? Also, do they have a built in amplifier or not? What size are they and do they have any special mounting considerations? Any recommendations on replacement would also be appreciated.

As a footnote, on my previous car (a C6) I know the large speakers in the doors had a build in amplifier, and I assume a C7 is the same. This makes replacing them (just them) close to impossible.

So what are your thoughts?

dbirdhouse1

You are basically correct; each is powered and though sound is as subjective as any sense employed to judge this
system, it is not known for it's (rounded) detail that other systems whether factory or added can add. Having said that
it would call for some serious (costly) changes. Believe it or not, disconnecting the middle speaker in the dash has
been known to make some small improvements but any fundamental changes would call for a new central unit (not a new head unit) that everything
electronic/dash related runs through; audio, car wide sounds (bings, chimes, etc.).
In addition, Vettes are tough to work on as there is little extra room to work with and you might also have to deal with a few
little creaks and squeaks as they never go back together quite as tightly as they came from the factory.
I used to sell and install car audio decades ago and continued to work on my own cars from a C5 and a C6 but I have reached
the age/physical limitations and financial limitations as well (retired teacher) that I saw it as diminishing returns.
Hope this helps and good luck

Mayor111

I think you mean "BASS"...as in BASS and TREBLE

JMII

Title is confusing due to it being BASS not Base, anyway...

Those little speakers behind the seats are likely attempting to be full range which will never work. Plus they are behind you which ruins the sound stage, thus I wouldn't even bother with them (run the fader to the front).

If you want to improve the sound system you'll need a dedicated subwoofer and not that joke of thing Bose / GM put in. The Bose system is combination faults: bad audio processing, cheap speakers that have a limited range and a tiny amp that can provide enough power. If you don't clean up the signal replacing the amp or speakers will be a waste. However the challenge is everything is integrated so its hard to just swap one part (like speakers) and get any improvement, you pretty much have to replacement it ALL to make things right.

With that said I actually think with a decent DSP processor and enough amplifier power the stock speakers (with proper crossover points) would sound decent. Still have to replace that silly subwoofer with real one. I am going to try putting a 8" Kicker CompRT 8" in the factory sub enclosure as its specs align with that size box, it just needs to be sealed as I believe the factory box is ported.

shakinrock

That darn spell checker, yes bass not base. Anyway, just to confirm, the speakers behind me seats do or do not have a built in amplifier? In my opinion, if they do not, little would be lost by replacing them with the best woofer at that size that I could find. If I hear no or little difference, return them. In the house I run NAD equipment so I know all about how the quality of the amp, especially dynamic range, has a drastic effect in the overall sound.

We all know that low frequencies bounce all around so the fact that they fire into the back of my seat is not a problem (for low frequencies anyway). What is a good car audio smallish woofer these days?

Lastly, I previously had a C6 and I did disconnect the center front speaker (probably a $5 item) and did notice a slight improvement in overall sound.

JMII

Sorry I missed the fact that you have a convertible... I was talking about the coupe.

With the Bose system each speaker has its own amplifier channel. Well technically the front door woofer and tweeter share a channel, but the mid is separate. In the coupe its a 9 channel system with a dual voice coil sub. So 8 unique channels feeding 10 speakers. So the basic answer is YES you could just replace the speaker if desired.

Not sure if someone has this same diagram for the convertible...

PHILLIP YOUNG

Virtual Geezer

I've had the Bose system in four Corvette generations: C4, C5, C6 and now, C7. Although each generation provided, in my opinion, a subtle improvement, it's still nothing to write home about. I've had Bose systems in other vehicles that were really quite good. The Corvette's systems have always sounded 'muddy' to me. I've concluded that it may be the "sound space" inside the car itself that may be the culprit (size, shape, plastic panels, resonance, etc,). I've had two coupes and two convertibles, and the results are similar. Most importantly, for me, is that I do not buy Corvettes for their stellar sound systems.

shakinrock

Thanks for all the information. I'm sorry but I am still a little unclear on one point. I'm not 100% sure what is meant be 'amplified channel'. Let me try it this way. Do the rear speakers in my '15 2lt vert have a built in amplifier or is the signal coming to them already amplified? Sorry again for being a little slow on this one.

JMII

The C7 has a central amplifier, it handles all signal processing and amplification via several channels. Each speaker is just wired to the amp via your standard + and - speaker wires. Thus you can swap the speakers without changing anything. The results will be sub par but you can do it - plug-n-play. The Bose system uses a non-standard ohm configuration thus aftermarket speaker (normally 4 ohms) will likely sound weaker (less volume). I believe the factory speakers are something like 1.6 ohms. The amplifier is pathetic at 38 watts a channel per someone of this forum that took one apart and checked the internals.

shakinrock

Interesting. So is the amp a stand alone component and can it therefore be swapped out? ie plug n play

speed4tu

Might wanna check the impedance of the factory speakers before you try swapping up amps. A lot of the Bose systems used to use 1/2-2 ohm speakers. Most aftermarket systems and amps are based around 4 ohm componets for mids/highs

JMII

Yes and no. You'll need an OE interface module like this: https://axxessinterfaces.com/product/AX-DSP-MOST1

Once you get a clean signal using the Axxess unit you can then plug-n-play with any amp(s) you want by using the supplied Axxess harnesses. Then if desired you can replace whatever speakers you wish. Using an aftermarket amp will eliminate the odd ohm configuration of the Bose (provided you replace the speaker too!) plus give you lots more power.

This is pretty much my plan to fix the crappy Bose system. I am only going to replace the factory subwoofer (at first) because I think with a clean signal, better crossover points and a real amplifier things will improve greatly based on my research and experience (been in car audio as a hobby since the mid 80s). Then a tuning session using the DSP (31 band EQ with time delay) I can get it sounding up to my standards.

Its really just the lack of true low bass and the volume variable Bose processing (EQ) that I hate about the factory system. Next week I am going to get my calibrated microphone setup working (hopefully) and do some analysis on the factory sound to visualize it weak points. My ears tell me one thing but I'd like to have some objective data to back it up.

shakinrock

hum, good discussion

so I started out this thread questioning the two speakers behind the seats in my vert. What about the single speaker mounted to the back / inside of the trunk? Can I just try a different aftermarket speaker (eg sub) assuming I find one with the same ohms? Is this factory speaker also (approximately) 2 ohms?


Again my car is a very, not sure if the coupe has the same speaker.

Jaylars

Have you considered this simple addition? I have one of these and some front Focal components in my wife's SUV and it vastly improved the quality and volume of the OE head unit.
http://www.jlaudio.com/car-audio-sub...ified-microsub
I am thinking about adding one to my GS Coupe.

BLACKCREEK