[QUOTE]Originally posted by WLAURENT
[B]One other last thought - did you wire your sub in series?

Since it is a Dual Voice Coil (2x2ohm):

If you wired it in series you would have a 4 ohm load and get 150Wrms from your amp.

If you wired it in parallel you would have a 1 ohm load and your amp is not 1 ohm stable - so it may be entering the protection mode.

The image below shows a dual voice coil (2x4ohm) possible configurations. Your sub is a dual 2ohm coil sub - but the idea is the same.

You will want your sub wired as shown in the lower drawing.


Actually I have the SWR-1041D which is a dual 4ohm voice coil. I currently have it wired in an 8ohm configuration (Example 1). So, based on your comments above if a dual 2ohm is wired in series to produce a 4ohm load and subsequent 150Wrms then in my case a dual 4ohm wired in series should produce a 2ohm load and 300Wrms? Wiring example #2 below?

 

Another tidbit - one of the documents I referenced earlier Alpine highly recommends using the V12 MRD amp line in a 2ohm load for optimal performance.

 

Sorry - mis-read your sub model

OK - so if you have it wired in series (8 ohm mode) - you would be lucky if you are getting 75W to your sub.

In this case - you should have it wired like the top drawing in my image or example 2 in the sub-woofer manual image you uploaded.

This will give your sub ~4 times the power you currently have.

 

Can't wait to give it a shot when I get home from work. ~4x the power might make somewhat of a difference!

 

Sounds like you've figured that out! Let us know if that fixes the problem.

 

Well - - - my sub nearly jumped out of the trunk. I still need to play around with the 'input'/gain to get it to somehow play a little more bass at lower volumes but as for mid to high volumes in THUMPS! Thanks to WLAURENT for is time and persistance!

 

Hi TampaS2k,

I'm planning on installing that radio. What frequency did you set the low pass filter for the sub on the built in crossover to ? The manual says you can set it to 80, 120 or 160 Hz.

Thanks.

 

[QUOTE]Originally posted by ATLJV
[B]Hi TampaS2k,

I'm planning on installing that radio.

 

I have finally got the bass that I wanted - at all volumes. Being my first sub project of any kind I made several critical errors which extended my project results.

1) Incorrect wiring of the sub - had it wired with 8ohm load - change to 2ohm
2) Sub box volume toooo large - used expanding foam to decrease internal size.
3) To further decrease any air leaks used expanding foam on sub box top seal and used silicone to seal the sub onto the box.

4) Made modifications to amp configuration based on Alpine's demo board recommendations.

ATLJV,

I set the LPF on the head unit to 120hz - I set the LPF on the amp to 100 (I do not listed to very low bass music so this give me a little more bass with the music I listen to). I also set the bass level to about +2 at 120hz. I have rear speakers which play the mid-bass very well which can drown out the sub if too high.

For those wanting good bass without blowing the trunklid a single ten is a good compliment - even with the top down.