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I'm looking for a woofer in doing the glitter pattern and need opinions about its proper size, frequency response and power.

As I understand, its power should be at least twice that of the amplifier used, right?

Also, it was mentioned in the Journal of Guitar Acoustics that another smaller speaker, said 4", might be needed to see the nodal lines more clearly in the frequencies of 300 Hz and upward. Is it necessary to have two to do a good job?      

Thanks for any input.

Bump!

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

I've used a hand-held 5" long-throw woofer for everything for years. Well, several of them, in fact. The RadShack '40 watt' speakers I've been using are actually only good for 20W RMS of constant power, and the sine waves are hard on them. No matter, RadShack doesn't sell speakers any more, so I'm going to have to find another source when the ones I've got get smoked.

Larger speakers _radiate_ more efficiently at low frequencies, but may _couple_ less effectively with the plates if the antinodal areas are small relative tot he speaker diameter. In theory the larger speaker should require less power to work, in practice, it may not. In the end, then, if you've got a wimpy amp (say, less than about 10W) you may need two speakers to work well. 20W or mare should work fine on almost anything with a 5" speaker. The exception is loking at modes on assembled archtops, which typically tax my 30W amp and speaker combo.

As usual, no one 'right' answer.

Right on... I knew Alan would have the answer...

If you want a great speaker distributor, you guys can have a look here:

Parts Express

If they don't have what you need, I think you're out of luck.

(a throwback to the days I was studying speaker building...)

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

Seems to me that a good powerful full-range car speaker might do the trick too. That way you cover most of the spectrum except any holes in the cross-over.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Thanks, Alan and everyone for sharing. I've got a 20W per-channel stereo amp. I'll get a 5" one as suggested. Alan, what about its suitable range of frequency response?    

As I understand, the sweeping should start from around 50 Hz, so the speaker should be capable from this low, right? what about the high? Or the high doesn't matter much as most speakers can still well handle the signal of thousands Hz level which should be enough for this job?

Thanks.

Again, I use a long-throw woofer, probably made for car stereo. It's probably rated from 20-500 Hz or something like that. I'd think anything in the ballpark should work fine. All you can do is try it.

I have this little monitor by me every sunday when I play drums. It's
powered, has XLR and 1/4" inputs, and a volume knob. I use it to run
piano to me separately so I can get a better piano level than I get through
the main monitor mix. They're relatively inexpensive and I thought they'd
work great for this when I was thinking about it. I could just run an 1/8"
to 1/4" cable from my powerbook and be in business.

Thanks for the advice, guys.