View Full Version : Altec N3000-E repair help

06-30-2019, 11:57 AM
I picked up a pair of Altec 601C and their associated N3000E crossovers but didn't realize there was an issue until I started working with them. I know the handles were missing but it turns out on both crossovers the shafts of the attenuators have been snapped off below the top of the threaded poles. Not really repairable so I am in need of replacements pots. Any recommendations? UGH!


Earl K
07-02-2019, 08:19 AM
Here's a schematic ( as drawn by a LHF member ).


From this thread (http://www.audioheritage.org/vbulletin/showthread.php?7257-n-3000-xover-schematic-for-601c-Altec)

> I guess I would start by looking for an affordable 3 or 5 ( wirewound ) 25-30 ohm potentiometer ( rheostat ) .

> Failing that ( search ) I would use an 8 ohm 50 watt variable Lpad (https://www.parts-express.com/parts-express-speaker-l-pad-attenuator-50w-mono-1-shaft-8-ohm--260-255) ( wired between pins 1 & 2 > which is where the variable resistance is typically measuring 0 to 30 ohms ).


07-09-2019, 07:35 AM
Thanks Earl. It appears you are colluding with a Russian here.
It may get down to physical characteristics with this for a similar fit and finish. Or I just go external with the new ones and if that is all that extends through the cabinet, it's all one sees.

Or heck, just build new crossovers entirely and pretend the old one was probably out of spec anyway. damn tar ridden thing!