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View Full Version : 1960's Altec "Capistrano" N800 Crossover Rebuild Questions



sanjosemichael
12-16-2017, 02:00 PM
Picked up a pair of Altec speakers about a year ago, finally getting to the rebuild. 803B low frequency, 804A high frequency with 811B horns, N800E 16ohm crossover(same as contained in the official "Capistrano" cabinet). The custom cabinets for my find were very ugly and long gone.

I unpotted the crossovers (a pain in the...). Did some digging to find N800D, N800E, N800F schematics and upgrade schematics. Settled on one that came up in an old post on the Altec Heritage Site, drawn by one Jack Gifford and commented on by the Legendary Zilch. See below.

Caps:
Original N800E caps were 2 each 10.5 mfd contained in box, not sure if they were film/foil/wax/what (anyone know?), but they were vastly out of spec. I will replace LF with 10.5uf and HF with 4uf. Probably go with Dayton Polypropylene Capacitors from Parts express, unless anyone out there can advise otherwise.

Resistors:
Original network surprisingly tested within 2 or 3 percent, with seized up stuck selector switch. I will replace this with the 20 ohm 4 watt wirewound and a Parts Express 16 ohm L-Pad.

Inductors:
Original are 3mh iron core. Since I'm virtually doing a rebuild, would it make sense to replace these with new air core inductors?

Let them know what think, any advice, new perspective, etc always welcome.



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gdmoore28
12-23-2017, 02:56 PM
Hi Micheal,
For some reason, this is the first time your post has shown up on my screen. Odd.

- Typically, if folks simply want to rebuild their original crossovers, the only thing replaced outside of sticky switches or frozen L-pads is the capacitors, as they seem to be the only component that goes bad rather consistently.

- Those who wish to upgrade the original design, simply build a completely new version with fresh and modern caps, resistors, L-pads, and air-core inductors. Not terribly expensive or difficult.

- Those who want to move to a new, better design seem to gravitate to the Model 19 or Z19 derivation of the original Model 19 crossover. You can find the extensive threads on those by searching "Altec Model 19 Crossover," "Z19 Crossover," etc. You will be taken to loads and loads of links which will give you variations on those, construction tips, schematics, and conversion to 16 ohm units if that's what you have.



Feel free to ask any more questions, and hopefully one of the REAL Altec experts will chime in to help. Welcome to the forum, by the way.

GeeDeeEmm