Japanese pots in L36

[oznob]

I am parting out a pair of L36 decades. I notice the pots are made in Japan. Did JBL use Japanese parts or are these replacements?

[GordonW]

Alps L-pad potentiometers (made in Japan) are very common in JBL speakers of that era. I've seen them in L100s, L166s, L26s, etc... you name it...

Of course, by this time, those Alps pots are probably way beyond their expiration date... and probably sound like hammered s***, assuming that you can readily get output from them at all. I've replaced a WHOLE BUNCH of them. Nothing really special- the normal 30w-50w L-pads from places like Parts Express are functionally (and cosmetically) pretty much identical...

Regards,
Gordon.

[oznob]

Thank you for the information Gordon, I do appreciate it! I have a pair of L-36's that suffered water damage to the cabinets but the drivers and crossovers seem to be working fine. I didn't want to sell the crossovers and mis-represent them as being original. The speakers are close in serial number but the pots seem to be different brands but both Japanese. I guess they put in whatever they had in stock?
Thanks again and best regards,
Mark

[LE15-Thumper]

Of course, by this time, those Alps pots are probably way beyond their expiration date... and probably sound like hammered s***, assuming that you can readily get output from them at all.
Regards,
Gordon.

What happens to them Gordon that a shot of cleaner can't help ? Are you talking about burnt windings ?

[scott fitlin]

What happens to them Gordon that a shot of cleaner can't help ? Are you talking about burnt windings ?

If they are older carbon type pots or L pads, as the wiper element and taper pad wears, not only do they become scratchy and noisy, the deteriorate sonically as well. Whenever I have had carbon pots replaced, even ones that werent noisy, yet, there has always been a big sonic improvement! Bigger, beefier, stronger, cleaner sound!

Pots and L pads wear out!

[oznob]

Can the pots be bypassed? If so, what are the advantages, disadvantages?

[duaneage]

If you are going to bypass the L-pads you should substitute a resitor network to provide a proper load to the crossover. The L-pads are designed into the network and simply bypassing them may change the crossover frequency, the output of the driver, or both.

I would replace them with the 50 watt partsexpress models, they are as close to the originals as you will find and are only a few bucks each.