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iconicmn
04-09-2015, 05:48 AM
Hello, I have a pair of Heathkit AS101 speakers, which have the same components as the Altec Valencia. Crossovers are different and are not in a sealed, tar-filled box. I'm rebuilding the crossovers, and there is a tandem pair of Lpads, one 8 ohm, and one 40 ohm, stacked and coupled so they turn together. The windings are ruined, so I need to replace the Lpads. Parts Express has no ability to cross-reference them, so I'm at a bit of a loss. There is a thread here in which Zilch says that a single 16 ohm Lpad can be used.

Athough I've followed this site for years, this is my first post. Thanks for any advice.

Earl K
04-09-2015, 01:25 PM
- I suspect you're getting confused by seeing 2 ( stacked ) devices ( & then assuming that's the quantity you need to replace ) .
Not so !

- You only need to buy a single ( modern style ) 8 ohm variable Lpad ( to satisfy the network requirements ).

- Your ( ancient ) pair of stacked potentiometers (https://www.google.ca/search?q=potentiometers&oq=potentiometers&aqs=chrome..69i57&sourceid=chrome&es_sm=93&ie=UTF-8) are simply ( when used together the functional equivalent of ) 1 modern style variable Lpad ( as seen in this example . (http://www.parts-express.com/parts-express-speaker-l-pad-attenuator-50w-mono-1-shaft-8-ohm--260-255))

- Here's a previous thread for some ( network ) reference .

-Help with Heathkit AS101 (http://www.audioheritage.org/vbulletin/showthread.php?34269-Help-with-Heathkit-AS-101)






:)

iconicmn
04-09-2015, 01:50 PM
Thank you! So the stack was basically the equivalent of the item to which you refer?

I do see that both of the existing potentiometers are shorted to each other at one terminal each. The speakers are 8 ohms. I will order them when I order the new capacitors.