Need help with subwoofer

[Bear6360]

Here's a webpage with the specs of my amp. It's the 4085.

http://www.usacoustics.com/specifications/mosfet_specs.htm

 

[Bear6360]

The above post is for the new amp, not the factory.
Here are the specs listed in the book that came with it:

1. RMS, per channel @ 4 Ohms @ 12.9v input - 85W x 4CH
2. RMS, per channel @ 2 Ohms @ 12.9v input - 120W x 4CH
3. RMS Bridged Mono @ 4 Ohms @12.9v input - 240W x 2CH
4. Input sensitivity, Hi Level - N/A
5. Input sensitivity, Low Level - 100mV-8V
6. Frequency Response - 10Hz-30KHz,-0.5dB
7. Total Harmonic Distortion - Less than 0.01%
8. S/N Ratio - 101dB
9. Channel Separation - 81dB
10. Damping Factor @ 20Hz - 95
11. Crossover Range (High Pass) - 12hz-200Hz
12. Crossover Range (Low Pass, 24dB/Octave) - 40Hz-200Hz
13. Bass boost, +18dB - N/A
14. High Level Input - N/A
15. Remote Level Port - N/A
16. Thermostatically controller fan - N/A
17. Protection (Reverse Polarity) - Yes
18. Protection (Thermal) - Yes
19. Protection (Short Circuit) - Yes
20. Protection (D.C.) - N/A
21. Fuse Rating - 30AX2
22. Size (inches; mm):
Length - 14.6 ; 370
Width - 9.6; 244
Height - 2.5; 63.5

Finding more data......

 

[Bear6360]

The first picture on the right is what the factory sub looks like when it's all sealed:

http://mz3.net/articles/044.html

As you can see, it's flat. I'll have to measure the opening.

 

[Bear6360]

Here is how someone put two amps into their Z3's trunk. As you can see, he put one of them where the old factory amp was behind the panel on the right.

I'll probably have to replace the factory one as well, but for now, I want to hear how it sounds powering just tweeters. Does anyone have any advice, comments, interjections, or concerns?

 

[illfos]

ok yeah i understand whats going on now. Your audio guy is gonna have to open those holes up more towards the center of the 2 speaker holes, or else the edge of the new sub will hang out the side(this is of course if you use a bigger sub like 6 or so) And If i knew what was behind those OEM subs I could tell you if you should remove that snorkle piece, the carpet, and that piece of plastic. I think it should fire right into the cockpit, and not be blocked by anything. This would be the way I would do it, just as long and the OEM sub spot has a back to it, to force the bass out the front.
If the guy is good, and you trust him. the ideal thing would be to rip all that crap out and start fresh. i think you could get an 8 in there or even a 10 possibly, if it's gutted.

 

[illfos]

bear i just don't understand this idea of powering the tweeters with the oem amp. the tweeters are not going to be any louder than they are now...and once you put an amp on the midranges you are going to blow them cause they are OEM, and even if you didn't blow them, they would be so loud you wouldn't hear the tweeters you have on the internal. OHHH and another thing, they are going to fire at different times, the whole thing will be out of sink. This is not the proper way to run a stereo and i would advise you to replace everything If you want to add an internal amp or just upgrade the sub.

 

[Bear6360]

bear i just don't understand this idea of powering the tweeters with the oem amp. the tweeters are not going to be any louder than they are now...and once you put an amp on the midranges you are going to blow them cause they are OEM, and even if you didn't blow them, they would be so loud you wouldn't hear the tweeters you have on the internal. OHHH and another thing, they are going to fire at different times, the whole thing will be out of sink. This is not the proper way to run a stereo and i would advise you to replace everything If you want to add an internal amp or just upgrade the sub.

Thank you. I just wanted to know how good of an idea having both amps would be. Apparently, it's a bad idea. I don't need to blow anymore speakers. I already blew my 3"s. Replace 'em with 4"s. It sounds better already. I just can't wait to get that amp in there.

So...you would only power the kick panels and the sub with the amp, right? I need to get that amp in there as soon as possible. I'll probably drag my feet once I get some decent sound in the car, but you'll be hearin' from me regardless.

 

[illfos]

yeah the kicks and the tweeters on one channel and te sub on another. But you need to relace those stock speakers and get a set of compnents. You can't put the aftermarket amp on your stock speakers. I think we r clear on that. Good luck Bear!