Problems with a Leslie 145
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slapmybass44
- Posts: 12
- Joined: Wed Feb 04, 2009 5:11 am
- Location: Bloomington, IN
Problems with a Leslie 145
I recently acquired a Leslie 145 and I'm not getting any sound out of the top speaker. I ran a few tests to try and figure out what was going on and I am at a loss. There is absolutely no sound at all. Bottom speaker is working fine and both rotate at both speeds fine. Any ideas?
Re: Problems with a Leslie 145
aside from check the connections / soldering...
(to the upper speaker)
or getting an electronics technician..
no.sorry.
(to the upper speaker)
or getting an electronics technician..
no.sorry.
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blakbeltjonez
- Posts: 325
- Joined: Tue Oct 19, 2004 10:16 pm
- Location: Florida
Re: Problems with a Leslie 145
i would first suspect a blown driver - the original Jensen driver was rated for about 10 watts, they are phenolic and are not able to be repaired (there are no replacement diaphragms available).. undo the driver from the upper rotor and put a meter on it ..... a normal one would read about 12 ohms, if it's open you won't get any reading, and that will confirm the blown driver. if you took out the diaphragm and inspected it, you'd probably see that the copper windings are dark from being overheated...... the voice coil becomes deformed from heat and rubs against the frame, and fails.
the old drivers don't like transients too much at loud volumes - that's usually the culprit, running the piss out of the Leslie to get the nice distorted sound... if you take it too far, the driver can die suddenly
you can get replacement drivers, i'd imagine if you did a search on the internet you'd find someone to sell you one. they probably won't sound as good as the originals but unless you're a purist you might not care that much and they are rated to handle more power. just make sure the replacement is 16 ohms so that the amp's output transformer sees the proper load.
a less likely culprit might be the wiring to the crossover, or the crossover itself, or the wiring from the crossover to the driver.
use a meter to check the continuity of all of the above.
the old drivers don't like transients too much at loud volumes - that's usually the culprit, running the piss out of the Leslie to get the nice distorted sound... if you take it too far, the driver can die suddenly
you can get replacement drivers, i'd imagine if you did a search on the internet you'd find someone to sell you one. they probably won't sound as good as the originals but unless you're a purist you might not care that much and they are rated to handle more power. just make sure the replacement is 16 ohms so that the amp's output transformer sees the proper load.
a less likely culprit might be the wiring to the crossover, or the crossover itself, or the wiring from the crossover to the driver.
use a meter to check the continuity of all of the above.