Should I get Subs or regular woofers?

[BP1Fanatic]

Do you think 130 RMS would be too little to drive the subs?

Not if you build a high efficient box. Download Hornresp and see if you can model a horn enclosure for the subs. That's what I did with a Kicker 08S15L74 for my Ford Ranger Supercab. I'm running a Boston Acoustic GT-42 in 3 channel mode. The amp tops out at 450 watts rms when 2 channels are bridged. Yet, the box is designed for 500 watts rms and the sub can handle 1,000 watts rms to each voicecoil.

An externally hosted image should be here but it was not working when we last tested it.

 

[tsmith1315]

Whether 130 watts is enough to drive the subs depends on your listening habits and the enclosure. If you don't need to share your bass with the neighborhood, 100 watts is probably more than enough.

Agreed. Especially since DeadSpeaker was using a head unit to drive his last set of woofers. Any reasonable power amp will fare well unless those woofers are just power hogs.

In general, the larger the enclosure, the better the efficiency of the speaker.

Correct, but clarified:

In general, a speaker that requires a larger enclosure will be more efficient than a speaker requiring a smaller enclosure.

And via the opportunity cost, efficiency is power.

 

[tsmith1315]

BP1Fanatic -if they aren't copyright, could you post larger views of those design sheets so we can have a look?

 

[BP1Fanatic]

Sure! It's purely my design.

An externally hosted image should be here but it was not working when we last tested it.

 

[tsmith1315]

Not to hijack DeadSpeaker's thread, if this discussion continues, we can start another thread...

BP1, I haven't used hornresp. I have a couple of Q's:

Is the (0.5 x pi) parameter to describe the space the system radiates into?

The graph shows 50Hz about 11dB down, how does the in-truck response seem to correlate to the prediction on the low end?

To be sure I'm looking at the implementation correctly -it appears that you've divided the mouth in half symmetrically along it's length, is that correct?

 

[BP1Fanatic]

Not to hijack DeadSpeaker's thread, if this discussion continues, we can start another thread...

BP1, I haven't used hornresp. I have a couple of Q's:

Is the (0.5 x pi) parameter to describe the space the system radiates into?

Yes, 1/8 space since the horns are firing into both corners.

The graph shows 50Hz about 11dB down, how does the in-truck response seem to correlate to the prediction on the low end?

There is a thread on DIY where JBL took in-car measurements of various cars & trucks. The pickups had gains of 12-18 db's at 50 hertz and 25-30 dB's at 20 hertz.
http://www.diyaudio.com/forums/showthread.php?threadid=128937

To be sure I'm looking at the implementation correctly -it appears that you've divided the mouth in half symmetrically along it's length, is that correct?

Correct!