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Gary L
08-08-2017, 04:30 AM
I just finished restoring a pair of 9844A speakers that were a real mess. I had all the woofers rebuilt at GPA and new diaphragms for the 806A horn drivers.

Here is where I am stumped. The original 800F crossovers were removed and replaced with 801-8A XOs. All the wires were there but not hooked up when I got them. The woofers and horns are all 16 ohms. On the horn driver I installed the diaphragm + side to the #2 terminal. I have the woofers hooked to the LF side on the rear of the XO, Green wire to the + red terminal and black to the - black terminal on each LF driver. On the rear of the XO I have the red wire hooked to the + HF side but I don't know if the red wire is supposed to hook to the #1 negative side or #2 positive side on the 806A horn drivers. I just do not understand this phase shifting electrical talk where 2 LF 16 ohm drivers hooked in parallel drops them to 8 ohms but the single horn remains at 16 ohms.

Where should the red wire from the HF + side on the rear of the XO be hooked on the horn drivers or does it even matter?

Thank you

Gary

Earl K
08-08-2017, 05:06 AM
Pull a crossover Gary & post a pic of it clearly showing the colored wires ( as connected ) to the back of the N801.

Without the pic, I don't think anyone can help .

:)

Gary L
08-08-2017, 05:18 AM
Pull a crossover Gary & post a pic of it clearly showing the colored wires ( as connected ) to the back of the N801.

Without the pic, I don't think anyone can help .

:)

Thanks Earl.

Red is on the top left HF+, Green is on the top right LF+

77771

Earl K
08-08-2017, 05:29 AM
Here's a Google pic showing similar available wire colors ( here, going from the original N800F crossover to the components ) .

- Clearly, Black is used as the common ( negative side ) for all drivers.

- Red wire ( HF+ on the 801 network ) goes to L1 on the horn.
-Green Wire ( LF+ on the 801 network ) goes to the + terminal ( left terminal ) on the 414

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=33726&stc=1&d=1218473048

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=28915&stc=1&d=1191900237
http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=29785&stc=1&d=1196725210
http://i183.photobucket.com/albums/x316/skywaverider/Aunt%20Molly%20Tribute%20Gathering/Altec%209844-8B/IMG_1732.jpg


:)

Gary L
08-08-2017, 05:37 AM
Here's a Google pic showing similar available wire colors ( here, going from the original N800F crossover to the components ) .

- Clearly, Black is used as the common ( negative side ) for all drivers.

- Red wire ( HF+ on the 801 network ) goes to L1 on the horn.
-Green Wire ( LF+ on the 801 network ) goes to the + terminal ( left terminal ) on the 414

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=33726&stc=1&d=1218473048

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=28915&stc=1&d=1191900237
:)

Perfect and that is exactly why I am so confused. When I installed the new horn diaphragms I followed the instructions I found here and the terminal marked #1 on the left side is negative to the diaphragm. #2 on the right is the + side to the diaphragm. Is it possible I installed the diaphragms reversed, should #1 be the + ???

I followed these instructions for the 800 series drivers, L1 is the black to the diaphragm and L2 is the red. https://greatplainsaudio.com/wp-content/uploads/2016/06/SmDrvrDiaRpl.pdf

Gary L
08-08-2017, 06:38 AM
Here are pictures of the inside wires and connections and I still think I have something wrong.

Based on Earl's pictures the horn driver should have the red wire to post #1 which in my picture is the negative side and the reverse of how I have them.

777727777377774

Earl K
08-08-2017, 07:22 AM
Hi Gary,

Some Reading at Hostboard (http://www.hostboard.com/forums/f700/68365-288c-terminal-polarity.html) from Todd.

From his dissertation it appears that "L2" was the positive polarity ( giving a compression wave when a positive signal is applied ) for the older style compression drivers.

The basic problem would appear to be that Altec swapped the physical orientation ( looking at a back-cap, going left to right, with the 2 terminals at 12-o'clock ) of where "+" physically occurs ( when they went from old style to the new style back-cap ).
- ie; It's now on the left, instead of being on the right .

I would just swap the wires going to the HF drivers ( from where you currently have them ).



:)

PS; I typically check all my connections with an electronic polarity checker so that I know what's actually what ( when it comes to positive & negative compression waves > though that doesn't really help you here ) .

PS#2; The bottom two pics I previously posted are of Skywaves 9844 system and were taken when he was messing about with different crossovers ( you can see the original crossover is out-of-circuit in the top left , inside the box ).

Gary L
08-08-2017, 08:07 AM
Hi Gary,

Some Reading at Hostboard (http://www.hostboard.com/forums/f700/68365-288c-terminal-polarity.html) from Todd.

From his dissertation it appears that "L2" was the positive polarity ( giving a compression wave when a positive signal is applied ) for the older style compression drivers.

The basic problem would appear to be that Altec swapped the physical orientation ( looking at a back-cap, going left to right, with the 2 terminals at 12-o'clock ) of where "+" physically occurs ( when they went from old style to the new style back-cap ).
- ie; It's now on the left, instead of being on the right .

I would just swap the wires going to the HF drivers ( from where you currently have them ).



:)

PS; I typically check all my connections with an electronic polarity checker so that I know what's actually what ( when it comes to positive & negative compression waves > though that doesn't really help you here ) .

PS#2; The bottom two pics I previously posted are of Skywaves 9844 system and were taken when he was messing about with different crossovers ( you can see the original crossover is out-of-circuit in the top left , inside the box ).

Yes Earl, I think I am going with your suggestion. My horn drivers as shown are the old style caps with the terminals up and the #2 is on the right side and is +. All of your original pics show they swap polarity to the horns and run the red wire from the + side of the XO to the negative side on the horns. I suppose there is a reason they do that but I don't need to know it as long as I have them wired correct.

Thanks again for all of your help. I did notice the pics you posted showing the newer horn driver caps the fellow ran the red wire to the red side on the horn which is the way I had it. All of my personal speakers are the model 19s so these 9844As with dual woofers threw me off.

Gary

Gary L
08-08-2017, 11:00 AM
Thanks again Earl. I have the 9844As playing now and they sound fabulous. I think I like the 2 12 inch woofers better than the single 15 in my 19s.

Gary