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View Full Version : Why are there two 1/4" input jacks on the n1209-8a crossover?



Dr. Jim Willie
05-10-2007, 08:39 AM
I have A7's with N1209-8a crossovers. They have (2) phono-jack inputs. The wire in a phono-jack is teeny. It looks to me like a beefier input would be a good idea, possibly spade jacks. To make this more interesting the crossover has two inputs, what is the intended use. If the speakers are not bi-wired (from one amp) or bi-amped, do they need a jumper?

Also, I saw some info on replacing "caps" (I think this means capacitors) is this something I should do, and how would I know if it is required and what I should do.

I saw on Jeff Markwart's site concerns about Altec Duplex phase corrected crossover designs, is this something I need to worry about.

The friend I got the A7's from said that the speakers are lacking in the higher frequencies and that I should add tweeters. Does this sound correct, if so, would I wire them into the crossover, how & what tweeter would complement these fine instruments?

Thank you very much!!!
Thank

Don C
05-10-2007, 08:50 AM
On some speakers there are two 1/4 inch jacks wired in paralell. They are both hooked to the input. The extra jack allows you to daisy chain speakers, so that you can run more speakers without having a separate line all the way back to the amplifier for each.

Zilch
05-10-2007, 09:14 AM
The friend I got the A7's from said that the speakers are lacking in the higher frequencies and that I should add tweeters. Does this sound correct, if so, would I wire them into the crossover, how & what tweeter would complement these fine instruments?http://audioheritage.org/vbulletin/showthread.php?t=14690

louped garouv
05-10-2007, 01:11 PM
looks like it is for using 1/4" plugs instead of spades, bananas, or ??? else....

to me at least, I never seen one in person

(pics from Ebay)

Dr. Jim Willie
05-10-2007, 01:17 PM
Thats what they look like. I want to change out that input for a better one. Suggestion?

louped garouv
05-10-2007, 01:19 PM
with regard to the lack of highs, pop the back of the driver off and see if there is a piece of black plastic covering the diaphragm...

if there is, this is a loading cap, and indicates your drivers are optimized for a littel more power, the thing to do, is send them to Bill at Great Plains Audio and have him put your 808-8Bs into 802-8G spec -- what this entails is removing the loading cap and replacing the screws with slightly shorter ones and adding some felt to the rear of the cover, and swapping out the higher power handling diaphragms with the aluminum ones.....

louped garouv
05-10-2007, 01:23 PM
Thats what they look like. I want to change out that input for a better one. Suggestion?


go active...

;)

can you open/close the enclosure? or does it require re-riviting to reseal them? depending, unless you can re-rivit the crossover enclosure closed, you may be "stuck"
if you are willign to break them open, go for what you like -- many folks like banana jacks....

http://www.action-electronics.com/grc/cesz16.jpg