Speaker Guru's needed.... - Page 3

Tomteriffic · 11-21-2002, 10:54 AM

JayMan, what everybody said

A good, cheap box stuffer is dacron polyester fiberfill, usually available at fabric stores for next to nothing. There's asome other, pricier stuff out there, such as AcoustaStuf, but if you're trying to do this on the cheap and keep what you have, dacron fiberfill will work fine

And Out and everybody, thanks for the links to the calculators.

11-21-2002, 11:11 AM

Indeed on the links. To date I only had a volume calculator for P.A. systems, and though the physics are the same, you don't typically build slant face P.A. enclosures!

I don't know about in car audio applications, but folded horns in live sound are taylored more towards bass drum punch than sustained low end. This is not to say that they don't resonate well, but I have never heard any that do as well as our ported 18" subs did. But the horns sure did beat the subs in the punch arena.

Not knowing what you like to hear in your car (and being hella out classed by some of other posters in the thread) I hesitate on what to recommend for you current situation. However, if those subs are free air subs, and you don't mind screwing a few screws into the floor of your trunk, you can disassemble the box they are in. Specifically, take the back and top off of the box. Then screw the leftover to the bottom of the trunk. Whallah, el-cheapo free air sub mounts. Sounds hack, but it worked fairly well for a buddy of mine who put a free air in the back of his GF's Beretta. Single Pioneer 350W 10" with a 200W @ 4Ohm Premier amp (bridged mono) and damn if that thing didn't sound awesome. It didn't have a lot of hit, but I don't like hit anyway (bass players are notoriously picky about resonant low freq bass response

).

Oops. Got winded. TomT is absolutely right about using dacron as a box filler if you choose to keep the box sealed. It's just there to break up the standing waves in the box and out of phase return waves and whatnot. You could use fiberglass insulation if you wanted (I am NOT recommending that!)

Man I miss having a custom system.

JayMan · 11-21-2002, 05:25 PM

Ok, so going by what dunbar has said.... If i were to port the box i would actually wreck the subs..... So i'm better of leaving it sealed...

From what out & TT said, I need to get some dampening stuff in there for a possible improvement....

Whir, could you how me a pic of what yoru talking about? I think i am understanding what your sayign but not sure.... But i don't know if i wanna go screwing it into the boot....

Out, heh yeh, here i was quite happy with how it was all sounding, just curious if i could get slightly better sound for cheap. And i get shot down & find out i was sold the wrong speakers for what i wanted & that the setup is crap etc...... oh well, life goes on!

JayMan

B71655 · 11-21-2002, 06:16 PM

Whir, three words: Klipshorn, 1812 Overture. The trick to a folded horn is the cutoff freq. The larger the horn, the lower it will go. Same thing with the average driver. Go to a library and get books on enclosure design. There will be some. No suggestions, my reading was 25 years ago. BTW, low freqs. need a lot of room in front of the speaker too.

crazyray · 11-21-2002, 06:58 PM

Quote:

Out, heh yeh, here i was quite happy with how it was all sounding, just curious if i could get slightly better sound for cheap. And i get shot down & find out i was sold the wrong speakers for what i wanted & that the setup is crap

I certainly didn't mean to cause you grief. Please note that Pioneer markets a very similar sub with the same model number but ending in "C". That model is intended for small sealed boxes.

To summarize, if you will be sticking with those and cannot go free air, best choice is as large a sealed box as you can use. Stuffing with dacron polyfill, about 1 pound per cubic foot, may help.

Good luck, and remember that the only person you have to please is you.

JayMan · 11-21-2002, 08:04 PM

Yeh i know CR. Just P/O'd with the place that sold the speakers to me. Oh well, i got them for a good price, and now i know why.... I wonder how much difference there really is between the F & the C models.... I wonder if pioneer would swap them around for me.... hmmm..... probably not hey... oh well...

JayMan

Brainchild · 11-21-2002, 08:35 PM

jayman, you mount those subs freeair,and It'll kill small animals. You can mount them backwards and use them as jet propulsion, well maybe not but they will kicka$$.

Poly-fil,(pillow stuffing) from good old wal-mart is a fair dampner(not the best) have used it a few times.Cheap, and readily availible is prolly why

Those folded horns are cool souding IMO.We used a pair of 18" EVs in folded cabs, they have a sound all thier own.

Backloaded speakers have a sound ulike any other also, but I don't think car audio would sound good in either of these cabs.

JayMan · 11-21-2002, 09:16 PM

ya's are making me wanna find a way to free-air mount them... but as far as i can see its just not really possible, unless i do something like CR posted above (the12volt website). But i don't have time or patience to do anything like that....

Hmm... i might have a look at something.... it might work.... but then i might mean the backseat of the car don't fit properly....

Also means the box i bought a while ago is wasted.... hehe it cost me just as much as the subs lol.....

JayMan

JayMan · 11-22-2002, 04:41 AM

Well, i am now more than ever confused! I sent an email to pioneer australia asking them which wouild be better for the F type subs, sealed or ported. This was the answer

Quote:

It is not recommended to use "F" type sub woofers in an enclosure. However if you need to put them in an enclosure then ported would be preferred. To obtain the best response the enclosure would need to be as large as possible and you will need to experiment with various size of ports to give the desired sound.

This is only a suggestion and not a recommendation.

So, yeh, i dunno what to do now..... I'm thinking pioneer should know what they are talking about.... So i might end up porting the box.... arrgg i dunno!!!! Wish i could easily free-air mount them & all this trouble would be solved! (altho i'd then have to find a place to put my amp hehe

JayMan

dunbar · 11-22-2002, 06:34 AM

Hey guy, lets make something clear as mud: ANY cone type driver with an open back can use a certain 'optimally chosen' port of some kind and not suffer. The books will tell you what why and when. Vance Dickason is nearly universally considered the guru of loudspeaker design for the home speaker builder, his most recent cookbook (?6th edition I think?) can be had for about $20USD.

EDIT: Price correction: BestBookDeal seems to think I'm half off! /EDIT