JBL Synthesis 10 Speaker Amp Adjustments

[mrmack]

I've got a 2003 V8 with the 10 speaker JBL synthesis. Everything is stock... so far. I got a new head unit JVC KW-XG700 and want to replace the factory head unit. I know there are plenty of adapters out there (scosche, metra, etc.)to keep the factory speakers and amp and I'll be using one but I have a few questions:

1. What has been peoples experiences with keeping the stock speakers and amp and just upgrading the head unit? The sound quality of the factory setup is dreadful, awful almost nonexistent highs and muddy lows, not to mention I can hardly hear the speakers in the rear doors. I'm hoping replacing the head unit will fix the sound quality.

2. Is the factory amp able to be adjusted gains, balance, etc?

I'm pretty sure the problem with the lack of sound out of the rear doors has to do with the gain settings in the factory amp but I'm not about to take the back of my ride apart just to check the amp.

I'm going start with replacing the head unit but my savings list includes:

Alpine PDX-5 AMP - 75x4 RMS + 300x1RMS Sub

Infinity Kapa Perfect 6.1 - 6 1/2 speakers + tweeter w/ crossover for the doors and tweeters in the JBL tweet spots (backs and fronts)

Fosgate P2D48 8" SUB

or

Kicker CompVT 8

I'm torn on the subs but at this point I'm still saving money for everything.

Any help on questions 1 and 2 would be great.

 

[Bigrupp]

Upgrading the HU will make a huge difference with the sound. As for the factory amp, the only adjustments you can make are through the HU. One thing that I had a problem with was some of the custom adjustments I made didn't seem to agree with the factory stuff and the sound was messed up. It may have been the interface that you need to use the amp and it took me a little while to figure out which adjustments I had to make to get it right. Until I can convince the wifey to let me upgrade all that stuff the factory stuff works pretty well.

 

[rdrunner]

So let me get this straight, you can hook up an after-market head unit directly to the JBL amp/setup even thought it's a proprietary setup? And it improves the sound even though only the head unit has changed? I assumed (yeh, I know) the sound was processed by the sound processor in the amp and therefore I couldn't upgrade until I was ready to swap everything.

 

[Bigrupp]

You can't hook it up directly to the amp. You need a digital turn on interface for the amp to work.

 

[rdrunner]

So with an interface works with existing amp and improves sound? Sorry for sounding dense but this is new to me. It would help upgrading in steps instead of everything at once.

 

[Bigrupp]

Upgrading everything at once would definitely be better. However, that can be extremely expensive. Starting with the head unit is a great place to start. Aftermarket HU's generally put out more power and sound better than stock, so it makes sense to start there and build around it. If you can afford it though, it is easier to do it all at once so you don't have to take everything apart more than once or twice.

 

[rdrunner]

I understand that but thought since I have the JBL 10 speaker setup I'd have to replace the HU and bypass or replace the amp which at that point I might as well do the whole thing. As you said that can be very expensive.

 

[Bigrupp]

Ok, I'll say it one more time. YOU CAN STILL USE THE JBL 10 SPEAKER SETUP IF YOU REPLACE THE HU, YOU JUST NEED AN INTERFACE THAT WILL MAKE IT WORK.

 

[drmorbius]

To adjust the factory system push in the right knob. Then use the up down switch to adjust. To move to the next adjustment simply push the right knob again and continue to step through the adjustments until you find the one you want. The adjustments are Bass, Midrange, Trebel, Fader(front to rear), Balance, and Surround(on or off) in that order. All adjustments are done in the amp in the rear of the vehicle, but the controls are in the head unit. The head unit "talks" to the amp digitally through a pair of wires called TX + and -. I believe that TX stands for transmit. For the record all HU's that are intended to be used with an external amp have the same output power called line level. Hope this helps.

 

[rdrunner]

Thanks for clarifying. I've just never heard of a "digital turn on interface" and didn't know what it was.

 

[drmorbius]

Thanks for clarifying. I've just never heard of a "digital turn on interface" and didn't know what it was.

Think of the controls in the head unit as a digital encoder. The turn on signal to the amp is just acc+B taken from pin 11 of the 20 pin HU plug. This wire has nothing to do with amp power, it's just a wake up signal.

 

[mrmack]

I'm talking about individual gains on the amp.
It probably does not have them.
I'm just going to pull out this weak system and put in a component setup. I can't believe how bad the JBL sounds. I sure would be pissed if I had paid the premium for this in a new 4R. Even in 2003 this thing had to sound awful. Maybe I'll just put in the new HU first, it can't sound any worse. Then put the new amp and speakers in after I secure the funds to pay for them.

 

[drmorbius]

I'm talking about individual gains on the amp.
It probably does not have them.
I'm just going to pull out this weak system and put in a component setup. I can't believe how bad the JBL sounds. I sure would be pissed if I had paid the premium for this in a new 4R. Even in 2003 this thing had to sound awful. Maybe I'll just put in the new HU first, it can't sound any worse. Then put the new amp and speakers in after I secure the funds to pay for them.

You are correct, there are no tweeks in the amp. I took one apart to see what was in it. The only reason I included the adjustments in my post was because my JBL system sounds great, I couldn't be happier.

 

[Essence]

this thread is full of redundancy, redundancy, this thread is full of it

 

[drmorbius]

this thread is full of redundancy, redundancy, this thread is full of it

:lmao:

 

[fo'runna so blu]

If you have the JBL system, then just get the TYTO-01 which is the interface that people are talking to you about. i have one in my 10 speaker Jbl 03 runna combined with my D3 and it works great. It actually does improve some of the sound function through the gain adjustments found on the TyTO-o1 and some of the eq function through my d3.

 

[rdrunner]

If you have the JBL system, then just get the TYTO-01 which is the interface that people are talking to you about. i have one in my 10 speaker Jbl 03 runna combined with my D3 and it works great. It actually does improve some of the sound function through the gain adjustments found on the TyTO-o1 and some of the eq function through my d3.

Thank you, that's the info I needed.

 

[juiceboxer]

On a Side Note, If I were you I would get the fosgate sub due to it needing a smaller size box, which gives you more room to play with.