Subwoofer in 1995 Q45t

[RyanH]

I read the article on Q45.org about adding a subwoofer to the stock Bose system. I got a line level converter from David Navone Engineering to tap the signal from the rear speakers. My level of knowledge concerning car audio is fairly high, but one thing I can't seem to figure out is an easy way to wire up the amplifire turn-on wire.

I have a copy of the FSM, but the wiring diagrams aren't very helpful to me, I guess I don't really know how to read them. Anyway, I was assuming that the amps on the rear speakers (and the fronts for that matter) must have a wire that tells them to turn on and off with the head unit. I am wondering if this is true, and if so, which wire is it?

If the amps do not have a discrete turn-on wire, does the CD changer have a turn-on wire? My guess was no, since you can eject and re-load the magazine with the car on or off, so it seems to me that its always on, or at least always has power.

I did try searching the forums, recent and arhived content, but didn't really find anything that answers my question. The Q45.org article mentioned wiring a switch into the dash, but I'm really hoping to have it be 'automatic,' like I had in the comepletly aftermarket system I had in my Honda before I got the Q last month.

Any help/ideas would be greatly appreciated.

[elwesso]

The amps and the CD changer are all turned on by the bose amp relay behind the ECU.. You could tap the turn-on signal from there, thatd be the best way IMO, theres no low voltage stereo turn on in the back of the car

[RyanH]

Thanks for the tip. I'll give that try next weekend and see how it goes.

[off2sobe]

Check out Navone's N902. Combined with the N774V you have your output and power.

AUTO TRIGGER CIRCUIT N-902 $33.50Order N-902

This new device was designed to supply +12 volts to activate aftermarket components with OEM decks that do not have electric antenna control leads. The N-902 works by sensing speaker voltage from terminals of a readily available speaker. When the speaker voltage is present, the circuitry activates and +12 volts DC IS produced on the green wire.

[qsiguy]

Power antenna is in the trunk, you can use the wire for that. Not sure which color, just check them with a voltmeter. Find the one that has 12 V+ when the radio is on.

I was also going to suggest the trigger circuit off2sobe suggested. There are many on the market, I have one in stock. It knows when the speakers have power and outputs 12V+ to turn on your amp or other accessory.

[RyanH]

I just saw that item on the site the other night, going to get one ordered and use it. I have the NE-7V, and I hooked everything up outside the car to make sure I wired it correctly, and it seems to work very well.

From the reading I've done on NICO, it seems most everyone is using ported boxes; does anyone have any idea on what I can expect with a sealed box? I'm using a Pioneer 768 watt amp driving an MA Audio 12" sub (121QX in case anyone is interested), wired for a 2 ohm load. I do realize that the placement of the gas tank has a large effect on the sound I'm going to get, but I'm just wondering if anyone has some experience with both ported and sealed boxes in the Q.

I've had the setup sitting in the trunk for the last week (haven't had the chance to run power yet, but I wired up what else I could) and had to use some string to keep the box in place. Does anyone have any suggestions for keeping my box from sliding around the trunk? I've tried jamming it hard into the left rear of the trunk, but I guess it’s just too big. I've got it tied to what I assume are cargo net anchors in the trunk right now, but that is a bit on the ghetto side for my taste. If push comes to shove, it'll be black bungee cords, but I'm hoping for a more elegant solution. I'll have to get a pic of the ghetto-ness tomorrow before I drop the Q off at the mechanic to have my front wheel bearings looked at.

Anyway, any advice or information anyone could provide would be greatly appreciated.

[qsiguy]

I have always preferred ported boxes. They are more forgiving of design variables and usually provide greater volume levels. I won't get into a debate over which is better as they both have advantages. It comes down to personal preference and the driver you are using. MA Audio probably has a recommended enclosure for that sub if you look it up on their web site or check your literature.

If I ever get around to installing a system in mine I plan to modify the compartment in the rear deck to vent bass into the cabin.

[RyanH]

I was just trying to get a sense of what seems to work better in the Q, ported or sealed. MA Audio gives recommended specs for ported and sealed enclosures, which is nice, as it allowed me to find a box that would work well without having to build one.