Vehicle: 2003 G35 Sedan w/ Bose Audio
Parts:
Alpine iXA-W407
Metra 40-NI10
PAC ROEM-NIS2
PAC TR-7
Metra ASWC
JDM Finisher & Controller
Stock Bose Amp and Speakers

Issue: After wiring everything together and installation, everything works and is functional. Success! Much thanks to Wrathernaut's DD post and all the others who have posted their installs online. The only problem I am experiencing is the lack of subwoofer output. It is non-existent. I've adjusted the audio control settings for Treble and Bass but don't actually hear anything from the stock Bose sub in the rear deck. The sound changes in the front and rear door speakers but nothing changes on the rear sub. I know the stock Bose speakers aren't anything compared to aftermarket speakers, but comparing the stock Bose headunit subwoofer performance to the new Alpine subwoofer performance, it's like night and day. Using the stock headunit, I usually set the bass to -2 or 0 depending on music and could could rattle the rear shelf if I increased it more (not my style but I know it could be done). Using the Alpine, when I adjust the Bass and Treble, it only seems to affect the door speakers.

Has anyone experienced this situation? Is there something I did not connect to retain the sub? I noticed when I connected the Alpine harness to the PAC ROEM-NIS2, only the front left, front right, rear left, and rear right channels were utilized between the two devices and did not include a separate sub channel. Does the PAC ROEM-NIS2 take the 4 channels from the the new headunit and then split it into a 5 channel signal? Please advise......

Your help is well appreciated.

 

The Bose amp generates the sub channel from the other four channels (probably just the rear two). If the four doors are getting a signal, the subwoofer is also getting its signal.

Possible problems are that your headunit is splitting the signal, as your headunit does have dedicated subwoofer channels, it may not be sending the entire range on the four speaker channels. Read page 13 of the owner's manual:

http://support.alpine-usa.com/produc...%20English.pdf

And make sure the High Pass Filter is OFF.

 

I went through all the iXA-W407 settings and was unable to get improved bass response. The HPF (High Pass Filter) is set to off. I performed a factory reset on the deck to assure I didn't overlook a setting, but nothing changed. When I increase the bass settings I experience a muddy mid-bass sound. It appears that I'll have to add an additional amp and sub using the sub RCA out to round out the sound. Or just replace all the rest of the audio components (Bose amp and speakers) with separates, a 5 channel amp, and a sub.

The purpose for this whole upgrade was because the stock Bose and HVAC controls fried. This occurred one year after dealing with the CD ERR F0 error. I disassembled the deck and successfully removed the jammed CD-R media but was left without HVAC controls and constant 75* air. Sigh.... Well, at least I have audio content and HVAV controls now....