Need a crossover for my new 400 lb center channel speaker...

**Altec Best** · July 26th, 2012, 02:26 PM

Originally Posted by bowtie427ss

I really think he needs a couple rows of par 64's across the ceiling in front of them, and maybe a couple pinspots in the back of the room focused just wide enough to illuminate the speakers themselves. Oh, and about 200 running feet of black backdrop to cover all the pink without undoing it's acoustic goodness. I'm afraid if AA sheetrocks that space, he won't like what it does to the acoustics of it.

Originally Posted by westend9

Yeah, rock will liven it up and reflect but I gotta' get after the guy for not finishing the walls, the rest of the house is magnificent! I know, a man has to do.....

Yup I'm with you on this Westend... Just the sight of that insulation breaks me out in hives !! I couldn't hang for long with all those fibers running amok !

Love the speaks though AA ! Just beautiful...

**analog addict** · July 27th, 2012, 12:57 AM

Originally Posted by LICORNE

You are in for a shock . Look at this 1930 add.

http://www.lansingheritage.org/image...lletins/7a.jpg

Heh, 14 lb crossovers? Nice if you can swing it. 12 db per octave, crossed over at 500Hz. I need to figger out how to determine the impedance, since I'll have 20 ohm woofers in parallel and a 20 ohm compression driver

The fiberglass doesn't bother me at all. Only if I handle it with bare hands for protracted periods of time does it bother me.

**tomt** · July 27th, 2012, 02:42 AM

Originally Posted by analog addict

I need to figger out how to determine the impedance,

since I'll have 20 ohm woofers in parallel and a 20 ohm compression driver

thats so easy now.

Passive Crossovers, Capacitor and Coil Calculator

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adam west will always be batman to me -

1?961

**Altec Best** · July 27th, 2012, 01:33 PM

Originally Posted by analog addict

I need to figger out how to determine the impedance, since I'll have 20 ohm woofers in parallel and a 20 ohm compression driver

The fiberglass doesn't bother me at all. Only if I handle it with bare hands for protracted periods of time does it bother me.

True AA, but you don't want to be breathing in those tiny fibers either for long periods of time...

Ok so if you have them in parallel then the woofers impedance should be halved 10 ohms.. If you have an 8 ohm compression driver it would make it much easier to match.. Not a big issue though.. This is for car speakers but the application is the same for home speaks as well..

Series Parallel Speaker Impedance

**westend9** · July 27th, 2012, 04:35 PM

Geez, sorry I brought up the insulation, I was just ribbing the guy. If I was in his shoes, I'd probably be making the same decision about the house.
Back to the crossovers---Those originals are a piece of art. Man, they knew how to build stuff back then. A network with new stuff shouldn't be that difficult to build, I'm thinking.

**Altec Best** · July 28th, 2012, 10:42 AM

Originally Posted by westend9

Geez, sorry I brought up the insulation, I was just ribbing the guy. .

Lance it is No BIG deal... It's just a personal experience with Fiberglas insulation..AA has heard this before, again No BIG deal...

AA is Happy with it, and that is all that really matters isn't it ?

**Panomaniac** · July 28th, 2012, 10:52 PM

You really need to measure the actual impedance for a good crossover. I'll get over there as soon as I can to measure for you. Might bring a digital x-over so we can play.

Maybe this coming Friday or Saturday?

**aditya** · July 29th, 2012, 01:42 AM

Originally Posted by Panomaniac

You really need to measure the actual impedance for a good crossover. I'll get over there as soon as I can to measure for you. Might bring a digital x-over so we can play.

Maybe this coming Friday or Saturday?

I have a feeling that we are heading for a good thread on the 210s here. Pano is great in the "systematic reporting back" area. His thread here on the A7s was one of the best. Right now I am just eagerly waiting to see lots of graph-ridden posts, more so b'coz of these particular 515s.

**analog addict** · July 29th, 2012, 01:44 AM

Originally Posted by Panomaniac

You really need to measure the actual impedance for a good crossover. I'll get over there as soon as I can to measure for you. Might bring a digital x-over so we can play.

Maybe this coming Friday or Saturday?

Friday night is VIP night at the Beer Bourbon and Barbeque Fest across town, and I was lucky enough to score a half price ticket. Sat is a possibility though...
Meanwhile, back at the ranch....

Oh yeah, I measured the DCR on the 515's, both were in the 9 ohm range, and about 4.6 when paralleled. I'm betting these were closer to 16 ohms. Also, I have this bad boy on a couple of dollies now, and have cleared out my whole main system in preparation for working/final placement.