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Keeping HU adding amps and speakers

Posted: Mon Sep 28, 2015 1:20 am
by johnrich
I searched and seemed not to find a thread. Hope I am not repeating. Want to keep Bose HU, it looks so cool. With new product it seems one could add amplifiers without too much hassle. Has anyone done so? It seems to me, based on the Shop manual that I could by pass the Bose amp and insert a four channel amp behind the radio wiring (with the HF feature). Many of the current amps have LF and HF input capacities. They range from 45 watts RMS on up! The newer Pioneer 4 channel amp is small and delivers 45 watts RMS per channel! Again has anyone accomplished this task in their Bonnevilles? This system should not interfere with the chimes, etc. in the HU, I assume.

There are many new speakers on the market now that carry advertised 2 ohm (In reality maybe a 3 ohm speaker) that are of high quality with Db ranges at 92 and 93. Has anyone simply replaced the speakers and kept the Bose amps in place? If so did they sound much better? I installed the JBL power series 6 1/2" speakers in a Corvette and they were loud and awesome sounding. Would think they would do the same in the Bonnie. Does anyone have experience with just speaker swap? If so, what is your conclusion?

Just a note in closing. Sound systems are somewhat like color. What color does one like and is the best? Very subjective. Car environment often is not the most ideal for perfect acoustic sound systems, however, I believe the Bonneville cabin is one of the better environments out there to create a great sounding system. Frankly Bose, (not always been a fan of Bose) does quite well with the treble presence , moderately dynamic mids, but muddy mid and low bass. Thus, I am thinking a couple options above could improve upon the system and one could still maintain the Bose HU. Any response with experience on these two considerations would be appreciated. Again to all thanks for a great site! =D>

Re: Keeping HU adding amps and speakers

Posted: Mon Sep 28, 2015 9:57 am
by nos4blood70
If you use a Line Output Converter, you can add an amp to the stock system. You will have to run new wiring from the trunk and into the doors in order to do so. My car did not have Bose, but before I swapped to my Pioneer headunit, I ran everything off of the stocker using this little guy:
http://www.sonicelectronix.com/item_499 ... oCMa7w_wcB

If you really want to improve your sound, you will need to ditch the Bose unit. I have a Pioneer DEH80PRS now, with a Kenwood 5 channel, and some Pioneer comps running fully active. It's all time aligned as well. Just recently I also fully deadened and insulated all of my doors. Whether it was a stock SE/SLE system, or the upper trim Bose or Monsoon systems, there just is no comparison anymore.

Re: Keeping HU adding amps and speakers

Posted: Mon Sep 28, 2015 2:30 pm
by Schlotzky
Most of the Bose speakers are highly sensitive and often 1 ohm. So you would likely lose a fair bit of power going to a higher impedence and less sensitive driver using the original Bose amps (from what I've read, the Bose speakers are likely upwards of 96 db@1w). On top of that, while I can't necessarily substantiate my claims as I haven't tried changing speakers or amps with a Bose headunit but have had a Bose headunit (full system), a Bose system with an aftermarket headunit, and a couple of delco premium systems all of the same era, I'm pretty sure the muddy mid bass you're getting out of the Bose system is due to the EQ in the headunit itself rather than a product of either the Bose amps or the Bose speakers. I noticed the same sound profile in my Delco Premium systems compared to the Delco Bose systems I've had, and the muddy mid bass was from the headunit and not any other point in the system.

In my opinion, if you aren't a fan of the Bose system's sound, especially due to the low-end response, you'll need to ditch the headunit for something aftermarket that has a flatter output response. Personally I hate aftermarket headunits (sounds like you may be in the same boat) so a better next step for you may be an external sound processor/Equalizer between the stock headunit and the rest of the system.

Re: Keeping HU adding amps and speakers

Posted: Mon Sep 28, 2015 3:22 pm
by johnrich
First off to both above thanks for timely and insightful responses! I do not mean to offend anyone on this site. What a powerful set of resources we have in ALL members! I know some call Bose junk. I don't feel that way. Each system has some strengths and weaknesses.

I have 2 systems I want to improve upon the Bose in the 01 and on the monsoon in the 03 both SSEI,s. I want to keep the HU's in each. Have a lifetime XM subscription in one!

Will look into the equalizer sounds exciting! Any brand suggestions?

My thought for starters was to put the JBL power series speakers in as replacements in the front, wire the rear door speakers to JBL POWER SERIES 6 x 9 in the deck lid, (disconnect the Bose subwoofer, rear Bose deck lids and rear door speakers) and add a power amp with a sub in the trunk. The JBL's are 2 ohm and tout 93 db. (May not be as loud as the Bose with 96 DB). I do have a professional JBL 12" competitive sub with an 800 watt rms JBL/crown amplifier. I think this could make quite an improvement! The highs and mids demonstrate substaniL presence and dynamic range now. The JBL's I Believe will add more. According to "experts" on the net the JBL GTI sub was designed and engineered by the professional division of JBL. Anyone in the audio world well knows the quality of the JBL sound system! I think this will work to improve the sound keeping the HU.

Anyone please feel free to give advice. Again thanks to ALL for making this site so
Much fun!

Re: Keeping HU adding amps and speakers

Posted: Thu Nov 19, 2015 3:08 pm
by Bugsi
Products like the PAC AOEM-GM21C work with similar year Grand Prix, but only show compatibility with the 1999 Bonneville. Does anyone know if the Grand Prix radio harness and the Bonneville harness from 2000-2003 were different? In any case, those adapters are for Monsoon audio and not for Bose.

I have to agree that if you're looking to improve the sound of the factory Bose system (which was very good in the 2001 Grand Prix GT we had), you need to ditch the factory head unit.

Correct me if I'm wrong, but I thought the 2000+ Bonnevilles could fit a double-din head unit. If that's the case, you can get so many more features in a Pioneer AVIC or Kenwood DNX or DNN system that I wouldn't hesitate to replace the head unit and all the Bose speakers and go entirely aftermarket.

In those head units you'll get:
GPS Navigation
Bluetooth integration for your cell phone.
USB inputs.
Analog Aux inputs.
HDMI video input.
Composite video output.
DVD/CD/MP3-Disk player.
Back-up camera screen integration.
Line outs for all four corners and sub.
Lots of audio tweaking with EQ and time-alignment settings.

I don't see any value in sinking money into the sound system and retaining the factory head unit.
One of those double-din units, dedicated amplifiers and a sub will give you a killer system with loads of functionality.

Re: Keeping HU adding amps and speakers

Posted: Fri Apr 15, 2016 11:22 pm
by Erinyes
Just a quick addition for anyone keeping the factory head unit - I just had 1 Factory Radio add an AUX port to mine. They were listed as out of stock for a replacement, and I couldn't specifically find a reference to adding the port to that particular unit, so I called them. $105 and they add the port. Works great. It seemed a bit pricey, but I've always been satisfied with the factory setup and I didn't want to spend the money to do a full upgrade. $105 seemed a reasonable compromise to be able to play from my phone.

Re: Keeping HU adding amps and speakers

Posted: Sat Apr 16, 2016 10:13 am
by 2003 SSEi
if your Serious about OEM appearance for a HU (and I was) there are options available to do such a thing. I Installed a Rockford Fosgate 360.3. This takes the Monsoon amp outputs and converts them into RCA outputs for amps. The The 360 also has 160 bands of adjustment. its not cheap, but neither is a headunit. JL audio also makes a product called Clean Sweep