12" woofer with ff85k - Page 3

tinitus · 28th January 2013, 03:51 PM

Quote:

Originally Posted by tuxedocivic

.... how about this guy: The Madisound Speaker Store

Stuff the cabinet well and it'll be pretty much a sealed box, but lots of extention. About the right sensitivity match.

wicked1 · 28th January 2013, 04:24 PM

I have been looking at that sb acoustics driver, but it's a bit low on efficiency.. Looks like that is the compromise, though... Frequency vs efficiency. Or spending more $$$ and getting more of both.
I've spent the morning reading up on xovers and am warming up to the idea of higher orders... not sure yet..

SpirosZ · 05:26 PM

I don't think you need more than 91db to match the 86.5db of the FF85wk.
In fact the SB woofer according to the FR diagram here (click on the picture and scroll to the third image) reaches approximately 93db in the frequency range you want to use it (<300Hz) and the Fostex is at around 88db above 300Hz.

wicked1 · 05:45 PM

I've got the older 85k (not wk) which is 89db, if I remember correctly.
Thanks for the link to the datasheet.. It doesn't look bad for my application.

actually, I just looked up the datasheet for the 85k vs the 85wk, and they're about the same on most frequencies... my 85k has a loud high end, which is where the extra efficiency numbers come in.

tinitus · 28th January 2013, 05:55 PM

would like to see in a shallow waveguide alligning it with the woofer

wicked1 · 28th January 2013, 06:50 PM

Planet 10 (or anyone w/ Acoustic Elegance experience), if I were to go all out and get those drivers, would you still go for a low crossover point, or maybe raise it to take advantage of the good mid-bass of the AE drivers? I think I'd still want to keep it relatively low, but maybe up to 600 or 800hz.
Or, is that a bad xover point, since there's usually a lot going on in those frequencies? Maybe there's no good xover point,so I shouldn't worry about that

.

planet10 · 28th January 2013, 06:56 PM

Quote:

Originally Posted by wicked1

Maybe there's no good xover point,so I shouldn't worry about that

.

The AE drivers (amongst the best available) do have good extension on the top, giving you lots of flexibility, personally i like to keep it near the bottom of the critical band, and where the impedances reach their minimum.

The width of the box (ie where bafflestep occurs), limits the ideal XO location if you are using just differing sensitivity to gain BSC... somewhere on the order of sqrt(2)/2 to 1 times 4560/baffle width in inches is the ballpark.

dave

tuxedocivic · 28th January 2013, 07:29 PM

Oh man. Sorry, but I kinda think using a nice AE driver is a bit of a waste in this application. Crossing low isn't what makes the AE woofers so great. If I had the money for an AE woofer I'd team it up with a nice horn and cross around 1000hz. Those are really nice drivers. With a FAST, all that useful extention gets buried. Yes, you need extention to make a shallow cross over, but it doesn't have to be nearly that good. Also, the AE woofers give up a bit of bass (still quite good) for sensitivity and extention.

tinitus · 28th January 2013, 07:48 PM

I think its the 15" that makes AE interesting, and since they all seem to have very light cones, I would choose the heaviest ?

wicked1 · 29th January 2013, 01:00 PM

I modeled a bunch of drivers in my boxes last night, and it doesn't look good!
The SB Acoustics one has a big bump on the low end. Plus I noticed their efficiency rating isn't db/W, it's DB/2.83v which is probably around 88db/w, so too low. The Acoustic Elegance speakers appear to be lacking bass. They show up as -2db all the way up at 100hz!
The Eminenance is even worse on the low end.

The Fostex, however was a flat line, gently curving and down -3db at 50hz. It was definitely the best of the 10 or 15 drivers I modeled last night.

I guess that brings the question... Can speaker modeling programs really be trusted? The models make the Acoustic Elegance spekaers look to be about the same as the Eminenance, and the Fostex look like the king of deep woofer drivers.. which from reading around on the net, it does not appear to be....

28th January 2013, 05:08 PM	#23
SpirosZ diyAudio Member Join Date: Jan 2013	I don't think you need more than 91db to match the 86.5db of the FF85wk. In fact the SB woofer according to the FR diagram here (click on the picture and scroll to the third image) reaches approximately 93db in the frequency range you want to use it (<300Hz) and the Fostex is at around 88db above 300Hz. Last edited by SpirosZ; 28th January 2013 at 05:26 PM.

28th January 2013, 05:39 PM	#24
wicked1 diyAudio Member Join Date: Jan 2008	I've got the older 85k (not wk) which is 89db, if I remember correctly. Thanks for the link to the datasheet.. It doesn't look bad for my application. actually, I just looked up the datasheet for the 85k vs the 85wk, and they're about the same on most frequencies... my 85k has a loud high end, which is where the extra efficiency numbers come in. Last edited by wicked1; 28th January 2013 at 05:45 PM.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
FAST build with an Alpair 7.3 and a 12" Peavy Pro 12 woofer	golgiapparatus	Markaudio	6	2nd November 2012 12:07 PM
Wanted: Volt 12" and 15" woofer	gengis	Swap Meet	0	12th April 2005 12:29 PM
WTB: Focal & Audiom & Volts 11", 12", 13", 15" woofer	gengis	Swap Meet	0	17th March 2005 02:29 AM
12" woofer advice	Duck-Twacy	Multi-Way	21	18th March 2003 01:27 AM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

28th January 2013, 04:24 PM	#22
wicked1 diyAudio Member Join Date: Jan 2008	I have been looking at that sb acoustics driver, but it's a bit low on efficiency.. Looks like that is the compromise, though... Frequency vs efficiency. Or spending more $$$ and getting more of both. I've spent the morning reading up on xovers and am warming up to the idea of higher orders... not sure yet..

28th January 2013, 05:55 PM	#25
tinitus diyAudio Moderator Join Date: Nov 2005	would like to see in a shallow waveguide alligning it with the woofer

28th January 2013, 06:50 PM	#26
wicked1 diyAudio Member Join Date: Jan 2008	Planet 10 (or anyone w/ Acoustic Elegance experience), if I were to go all out and get those drivers, would you still go for a low crossover point, or maybe raise it to take advantage of the good mid-bass of the AE drivers? I think I'd still want to keep it relatively low, but maybe up to 600 or 800hz. Or, is that a bad xover point, since there's usually a lot going on in those frequencies? Maybe there's no good xover point,so I shouldn't worry about that .

28th January 2013, 07:29 PM	#28
tuxedocivic diyAudio Member Join Date: Jan 2011 Location: Ladysmith, BC	Oh man. Sorry, but I kinda think using a nice AE driver is a bit of a waste in this application. Crossing low isn't what makes the AE woofers so great. If I had the money for an AE woofer I'd team it up with a nice horn and cross around 1000hz. Those are really nice drivers. With a FAST, all that useful extention gets buried. Yes, you need extention to make a shallow cross over, but it doesn't have to be nearly that good. Also, the AE woofers give up a bit of bass (still quite good) for sensitivity and extention.

28th January 2013, 07:48 PM	#29
tinitus diyAudio Moderator Join Date: Nov 2005	I think its the 15" that makes AE interesting, and since they all seem to have very light cones, I would choose the heaviest ?

29th January 2013, 01:00 PM	#30
wicked1 diyAudio Member Join Date: Jan 2008	I modeled a bunch of drivers in my boxes last night, and it doesn't look good! The SB Acoustics one has a big bump on the low end. Plus I noticed their efficiency rating isn't db/W, it's DB/2.83v which is probably around 88db/w, so too low. The Acoustic Elegance speakers appear to be lacking bass. They show up as -2db all the way up at 100hz! The Eminenance is even worse on the low end. The Fostex, however was a flat line, gently curving and down -3db at 50hz. It was definitely the best of the 10 or 15 drivers I modeled last night. I guess that brings the question... Can speaker modeling programs really be trusted? The models make the Acoustic Elegance spekaers look to be about the same as the Eminenance, and the Fostex look like the king of deep woofer drivers.. which from reading around on the net, it does not appear to be....