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f456gt
06-09-2020, 11:04 AM
Hi,

I would like to communicate with Altec 846A users who have replaced the original crossovers with Great Plains Audio N1200-8C.

Cheers,

Horacio

Ed Kreamer
06-09-2020, 01:13 PM
Hello Horacio,

First a question; Why do you want to change crossovers? Ok the Great Plains crossover is probably not going to work very well because it has been designed for different drivers with a n 8 ohm impedance and the 846a was a 16 ohm system.

It might suit you better to either re-cap your crossovers or build a new one. But don't throw your old crossovers away if you do. Store them someplace if you, at some point want, want to restore your speakers to original condition. I believe the Mod 19 crossover had an HF "boost" EQ built into the crossover. If this is what you are after, one can be easily built along the lines of the Altec 80923 and inserted between the crossover and the 806 driver. Values would have to be recalculated for 16 ohms. I hope this helps.

Have fun

Ed

f456gt
06-09-2020, 02:43 PM
Hi Ed,

Thank you for your note. I wrote to GPA and they recommended the N1200-8C, the only crossovers they have that work with the components in the 846. But, according to your info, it may be for the 846B only not the A and now it makes more sense.

GPA mentions that the Valencia suffers from the original dividing network, which crosses at 800 Hz, that's the reason why I would want to replace them but I will try to recap them anyway.

Regarding the attenuators, should I be better off with new modern pots or just clean them?

Best regards,

Horacio

bedrock602
11-01-2020, 04:54 PM
Hi Ed,

Thank you for your note. I wrote to GPA and they recommended the N1200-8C, the only crossovers they have that work with the components in the 846. But, according to your info, it may be for the 846B only not the A and now it makes more sense.

GPA mentions that the Valencia suffers from the original dividing network, which crosses at 800 Hz, that's the reason why I would want to replace them but I will try to recap them anyway.

Regarding the attenuators, should I be better off with new modern pots or just clean them?

Best regards,

Horacio

FWIW, I have a pair of Altec A7 with the exact same drivers and crossovers as the Valencia 846A. The A7's sound absolutely sublime with the stock crossovers (with original caps).

ralfoto
11-01-2020, 09:13 PM
Hi

I am about to get a set of 846a Valencia Speakers from the original owners family and they look a bit off to me...but I am new to all this.
The picture I include shows the interior with what looks like a "port" and also black box crossovers......no dial on rear of speaker. I asked if the owner had modified these but his widow states this is how they were from new....any thoughts would be appreciated.
I have not heard them yet as they had no source with which to try the speakers.

thank you87557

bedrock602
11-01-2020, 09:50 PM
Hi

I am about to get a set of 846a Valencia Speakers from the original owners family and they look a bit off to me...but I am new to all this.
The picture I include shows the interior with what looks like a "port" and also black box crossovers......no dial on rear of speaker. I asked if the owner had modified these but his widow states this is how they were from new....any thoughts would be appreciated.
I have not heard them yet as they had no source with which to try the speakers.

thank you

Is there a hole in the back panel where the original crossover would have been?

Chas
11-02-2020, 08:34 AM
I don’t think that is an Altec cabinet. For example, the 846A wasn’t ported with a pipe style vent like that as such, to my knowledge only the 846B was. It had a large wide gap that acted as a vent, where the 811 mounted. Also, they used a metal strut to help support the weight of the CD.

Or maybe you have a factory prototype? Also back then, all the components are usually Altec green or later on, only the woofers were gold.

Above is only based on what I’ve seen.:dont-know:

ralfoto
11-02-2020, 02:59 PM
Is there a hole in the back panel where the original crossover would have been?

NO actual hole...though it is "indented" as if there should be one there.....

ralfoto
11-02-2020, 03:01 PM
Definitely is a correct cabinet -Valencia- in excellent shape...These were mounted six feet high in a wall unit.....according to the widow never taken out until after her husband passed. I am a little hesitant as the crossovers do not look factory and there is no L-pad ....so maybe he had them modified in later years.

Chas
11-02-2020, 04:05 PM
Definitely is a correct cabinet -Valencia- in excellent shape...These were mounted six feet high in a wall unit.....according to the widow never taken out until after her husband passed. I am a little hesitant as the crossovers do not look factory and there is no L-pad ....so maybe he had them modified in later years.

Interesting, maybe a transitional design.

Ed Kreamer
11-23-2020, 05:24 PM
Hello Ralfoto,
By observation I can tell you that these are not factory boxes. They look like custom made boxe ,and the baffle looks stepped. Also the crossovers are not Altec crossovers. This may be not a bad thing. From the Photos I'd say they are quality boxes and depending on price, you may have stumbled on a good deal. As far as the drivers; Green is 16 ohm, black is 8 ohm. Gold were Altec drivers used by the Seeburg Juke Box company.
Does the seller have any information, drawings, or notes? You probably can reverse engineer the crossover and calculate where the constructor divided the the frequencies, and if it has an equalizer designed in.
Anyway, as long as they sound good, and the price is commensurate, buy them.

Ed

Chas
11-24-2020, 05:58 AM
Yes, that “step baffle” with the 811B mounted is reminiscent of the 846B Valencia, of which I do own a pair. The 846B also feature two round vents on either side of the woofer, made of cardboard tubes.

BTW, I have seen gold woofer frames in some systems like the two 414Z 12” that were in my old Carmels.

macsic
11-24-2020, 06:23 AM
Hello Ralfoto,
.... As far as the drivers; Green is 16 ohm, black is 8 ohm. .....

Ed


Hello, with all due respect just a small correction, I had several 846s and I had a pair with black drivers and they were in 16ohms, the color is more related to the year of production.

Here a photo I had removed the 416-Z from my 846 and it was black like the 806/811.
https://nsa40.casimages.com/img/2020/11/24/201124021652291303.jpg (https://www.casimages.com/i/201124021652291303.jpg.html)

I haven't used a GreatPlain crossover, an active crossover does just fine with the right adjustments for your room.
Anyway excellent speaker that I sold just a few weeks ago to make room

Ed Kreamer
11-24-2020, 10:41 AM
You may very well be right about the year of production. I admit that my knowledge is anecdotal. Were the black 416's that you had, built on the 16 inch frame or the older 15 inch frame. Altec would build 16 or 8 ohm versions to order.

bedrock602
11-24-2020, 06:21 PM
I have a pair of 846A's with green drivers and horns, all 16 ohm. The odd thing about these is that both woofers and one horn driver are hammer-tone green, the other horn driver is matte finish green. I also have a set of the exact same drivers in matte black, all 16 ohm.

macsic
11-25-2020, 06:03 AM
You may very well be right about the year of production. I admit that my knowledge is anecdotal. Were the black 416's that you had, built on the 16 inch frame or the older 15 inch frame. Altec would build 16 or 8 ohm versions to order.

Hi, I sold these 846 but I keeped the woofers for my A5 and they are on the older 15 inch frame, I got many 416 16 ohms all on older frame 15" in hammer-tone green, matte finish green and matte black.


Regards
Michel