CP-65 processor front panel hinges

[Gordon Lupien]

Maybe off topic for this forum, so please accept my apologies if this is true.

I'm sure others have broken lower hinges on their CP-65's as well. Is there a source for them, or has someone made them with 3D printing or some other method? I'm working on replacing the right hinge on two processors. Any hints would be very welcome!

[Tj Hopland]

Back in the day Dolby did sell those as a spare part so there would be a chance of some NOS ones floating around still. They didn't get damaged that often while installed but it was pretty common when they were getting moved around along with the fader knob getting bent or completely broken. It was the same hinges on many of the products, later 50, 200, 55 so there were a lot of them out in the world at one point.

Yes would be a good application for a 3d print. Not that complex of a design so should be easy for someone with basic design skills (not me). Could be printed on a cheap filament machine but I would think ideal would be a resin printer.

[Ryan Gallagher]

If not resin, at least maybe one of those hardier fancy filaments such as the fiber or carbon infused ones seems appropriate for a hinge that has some cantilever weight.

[Gordon Lupien]

I found a couple of CP-55's. Hopefully they arrive with h
good hinges. ?

I wonder if the CP-55 CAT 249's work in the CP-65. Seems like they might be the only module I can re-use to compensate for the "cost" of the hinges...

[Marco Giustini]

not an expert on those old CPs but I think that a 249 is a 249, it works wherever a 249 is installed.

[Steve Guttag]

I wouldn't use a CAT249 in a CP65. The CAT249 was weak even in a CP55. You can tell how long it was powered up by how burned it is on the bottom of the PCB. They really beefed up the CAT249A...right down to the larger capacitors that stick out of the card to the point you can't put a spare CAT249 next to it, like in the CP55.

Cards from the CP55 that work in the CP65 are:

• Optical Preamp. CAT240 is the transformer version of the CAT240A. Transformers are better for isolation and inherently get you a balanced input. The frequency response isn't quite a good.
• CAT222 works as a CAT22A (dual A noise reduction).
• CAT150 (shipped with CAT150C and eventually CAT150D). The "C" brought the SPI LEDs. The D was an improvement and had a flexible shield between the two boards.
• CAT64B (identical between the CP55 and CP65).
• CAT 242 (B-chain card) is essentially identical. Since the CP65 used the "Mag" input as an AUX, some of the input parameters are different on that input.
• CAT 241 (bass extension) works but eliminates the right surround as well as a digital subwoofer.

I think that covers the drop-in replacements. I don't recall if the front-panel board is identical; it may, very well, be identical (I don't have a book in front of me.

[Gordon Lupien]

Wow, thank you for the information, everyone! I'll have a surplus of Cat 249's, so I'll probably "burn" through those first.

[Tj Hopland]

The 249's in the 55's failed often enough with age that there is a decent chance they got replaced with 249a's later in their lives. The CP55 was still supported when different versions of SR and then SRD came out so Dolby sold upgrade kits that included different (basically the CP65) boards and stickers for the front panel and backplane to upgrade the labels. If you are looking at photos you can usually pick out the 241 vs the 441. The 241 had the normal metal head multi turn pots and a metal toggle switch very similar at a glance to the 160? OBE card of the 50/200. The 441 had a blue body with white lever slide switch and I think like 12 blue body white dial single turn pots for split surround and sub EQ.

I don't remember if the 55 had all the formats available like the 65 did. Going from memory I think on the format card under the 'wake up' jumpers there is a 2:4 NS jumper, that is to direct the front panel NS button to which ever version of NS you want. On the 65 both NS and 2:4 is available on the remote terminals, 55 may have been the same way. Seems like there were a few other tricks like that available if you are trying to do unusual stuff especially if you got into the format card.

[Gordon Lupien]

Got one hinge off of the CP55's, and one working CAT 259, amongst other things. The second CP-55 had the same right hinge broken! Gah!