Hi.
I recently installed a LUX-Nav TNR and 6-disc USA-Spec CD Changer into my 2003 ENVOY SLT. Everything works beautifully. Steering wheel controls work, RSA works, etc.
My one concern is this:
I have 4 EQ setting in the Audio config:
Driver, Rear, Normal and Spacious, as I had with the 6-disc Bose HU this NAV unit replaced. However, I notice absolutely no difference in sound or quality when I select Normal, Rear or Spacious settings. They all sound the same. The only one that gives a different sound is the Driver setting. It doesn't matter if I'm listening to Radio or CD. All other functions work perfectly.
Any ideas from anyone?

The Envoy amps are different from the GMT-800 Lux amps. I think the Envoy amps communicate with the radio in the same way as the GMT-800 Luxury amps do (meaning, they receive audio the same unique way, and thats why the LUX nav unit works with your Envoy), but they technically arent actual LUXURY amps per se. Meaning, they dont actually have an onboard DSP (digital signal/sound processor) like the GMT-800 Lux amps do. That would be my only guess as to why changing soundspace options seems to have no effect.

--Ben

The Envoy amps are different from the GMT-800 Lux amps. I think the Envoy amps communicate with the radio in the same way as the GMT-800 Luxury amps do (meaning, they receive audio the same unique way, and thats why the LUX nav unit works with your Envoy), but they technically arent actual LUXURY amps per se. Meaning, they dont actually have an onboard DSP (digital signal/sound processor) like the GMT-800 Lux amps do. That would be my only guess as to why changing soundspace options seems to have no effect.

--Ben
I don't know much about the sound system, but I know if you have a class 2 amp, you need to have a lux radio (non class 2, non lux radio). The Envoy amps (Trailblazer, Bravada, and Rainier too) had a changer over just like the H2's. I know 2002-2003 they used a class 2 amp (similar to the lux amp in the Escalade). In 2004, they switched to the non class 2 amp (Premium amp, non lux amp, Silverado style). So, it depends on the model year of the mid size SUV.
Dan

Thanks for the info DURAtotheMAX & machomachodan.
Ben...what you are saying makes sense because I had a look at my amp today. It's part #15187195 and it actually doesn't look like a typical Non-Lux amp. It also doesn't look like a typical LUX-amp either except for the fact it has three connectors as opposed to two. The one thing that confuses me is that the Bose 6-disc in dash cd-changer I replaced with the NAV unit had the exact same same sound field options and worked perfectly.
So I really am stuck on what I shoud do. Should I replace my Lux-NAV unit with a Non-Lux Nav unit? Should I, an can I, replace the amp with a LUX-Amp or sould I leave everything as is and just live without the sound-field settings.
Much appreciated guys.
Thanks for the help.

no, dont replace it. It most likely wont work at all. If it "works" with the Lux nav unit, it wont work with a non-lux nav unit. The Envoy's/TrailBlazers have used a variety of different speaker setups. One of them being a three-connector amp (i remember reading something about it). It uses the Class II data bus for volume and balance/fader control much in the same way a GMT-800 LUX amp does, but as I said before, it doesnt have any onboard DSP for creating the different sound fields. Its more or less a "bastardized" amp setup. I guess you could kinda think of it as a "wanna-be" Lux amp. I'd be willing to bet that on your old 6-disc head unit, it actually changed the outputs on the HEAD UNIT when you change soundfield options, versus the "real" lux systems, where the head unit just sends a data signal to the amp that says "hey, put your DSP into 'spacious' mode". I cant say thats exactly whats going on, but with my understanding of these entertainment systems, I can kinda piece together whats going on and I bet thats how the Envoy/TB amps work.

---Ben

strangley its an expensive little bugger!!!

530$ from GM Parts Direct!!
960$ GM List price!!!!

GMT-800 Lux amps are in the ~350 dollar range from GM Parts Direct, ~600 dollars GM List price.

Have you ever heard an Escalade/Denali Bose sound system? How does it compare to that? Id be curious...

---Ben

Ben...I haven't heard an Escalade/Denali system but I know that the system I had (Bose 6-disc) sounded really good.
I was wondering if it's possible for me to swap out my amp for a lux amp.
Would it just be a matter of simply swapping and connecting the 3-connectors or would I have to do any tinkering? The Bose Audio Pilot micophone for Auto Volume Control doesn't really concern me, as long as I could improve the sound quality I'm getting. Don't get me wrong...the qulaity is good...but the bass is a little lacking and I would love to have access to the DSP sound fields (Especially the "Spacious" mode).
Any info would be greatly appreciated.