Leslie 145 sounding muffled and dull

[boye]

Hey guys,

My A-100 leslie 145 setup is sounding a bit dull. I think the leslie is causing it because the organ isn't sounding dull when i am playing trough the organs speakers or my headphones (The A-100 has a line out). The 145 Amp is totally rebuilt so that cannot be causing it. I am not sure if the crossover is rebuilt but i will give you an update about that later. Can old crossovercaps cause this?

Thanks alot!

Cheers,
Boye

[nonreverb]

...a bad or misaligned coil in V21 driver might.

Hey guys,

My A-100 leslie 145 setup is sounding a bit dull. I think the leslie is causing it because the organ isn't sounding dull when i am playing trough the organs speakers or my headphones (The A-100 has a line out). The 145 Amp is totally rebuilt so that cannot be causing it. I am not sure if the crossover is rebuilt but i will give you an update about that later. Can old crossovercaps cause this?

Thanks alot!

Cheers,
Boye

[boye]

...a bad or misaligned coil in V21 driver might.

Thanks for the tip, I have had some problems with the coil. it wasn't aligned properly and was buzzing a bit. I fixed it myself realigning the coil until the buzzing went away. I have an extra v21 from my 760. Will try swapping them and check if i will hear any differences!

cheers Boye

[tdintbl]

Where on the A-100 is this line-out spliced in? That can have an effect.

[boye]

Where on the A-100 is this line-out spliced in? That can have an effect.

The Line out is tapped from the audio and ground signal on the female connector of the speakon plug (same as the 6 pin leslie cable) on the organ. So just before the signal goes into the leslie cable.

Would it be possible the crossover caps are causing this?

Thanks!

Boye

[Guest]

More likely yes. If it was a v21 diaphragm issue it'll be buzzing or not working at all. You'll spot it either ways. To be sure about the crossover just bypass it for a test.
Just curious on what setting is the load resistor?

[nonreverb]

Not necessarily. A V21 that has had the spacers changed or modified will indeed sound different....and usually worse. I found that out through experimentation many years ago.

It's a good idea to check the resistance of the load resistors in the Leslie as well. They have a tendency to go open as they're somewhat under rated.

More likely yes. If it was a v21 diaphragm issue it'll be buzzing or not working at all. You'll spot it either ways. To be sure about the crossover just bypass it for a test.
Just curious on what setting is the load resistor?

[Guest]

I do that same experiments in much more recent times:) and I can assure you "muffled and dull" are not the English terms that I would use to describe the changes. But that is, may be, my bad English, lol.
Nontheless I was referring yours "bad or misaligned coil" statement, obviously...
The thing is that a healthy A100, or for that matter any HTC, full range 12"(or other size) have more highs than the Leslie driver, IMHO. So that 145 may just be working as intended. Of course there are many other variables as speaker location in the room, phasing, input tube, crossover, kit used etc. we ignore at this time.

Cheers,
Boyan

[nonreverb]

Placing the coil too far out of the magnet gap via more spacers will cause the output level to decrease removing them can have the same effect. That's why they use spacers in the first place. It's what alignes the coil to the magnet. All V21's have them and no, they're not all exactly the same alignment. Problem is, people get in there from time to time to try and improve the driver and remove or add spacers. It never is an improvement and usually results in a buzzy or weak sounding driver.

I do that same experiments in much more recent times:) and I can assure you "muffled and dull" are not the English terms that I would use to describe the changes. But that is, may be, my bad English, lol.
Nontheless I was referring yours "bad or misaligned coil" statement, obviously...
The thing is that a healthy A100, or for that matter any HTC, full range 12"(or other size) have more highs than the Leslie driver, IMHO. So that 145 may just be working as intended. Of course there are many other variables as speaker location in the room, phasing, input tube, crossover, kit used etc. we ignore at this time.

Cheers,
Boyan

[boye]

Thanks for your replies!! I just ordered the caps for the crossover, I will check if a different v21 will make a difference. My leslie dousn't have a load resistor knob anymore. The amp was rebuild by a good tech in the netherlands but I am not sure why it is not there anymore. Again thanks for the good advice!

Cheers Boye

[nonreverb]

Let's see if I understand this. Is this the connector at the power amp on the bottom right? Is this signal actually derived from the preamp or the power amp. It will make a significant difference in the sound if it's sourced from the preamp as opposed to the power amp.

The Line out is tapped from the audio and ground signal on the female connector of the speakon plug (same as the 6 pin leslie cable) on the organ. So just before the signal goes into the leslie cable.

Would it be possible the crossover caps are causing this?

Thanks!

Boye

[boye]

Let me explain this more precisely, the signal is tapped from the poweramp. On the backplate of the organ a speakoncomnector has been made that connects the organ to the leslie. Another speakon connector is for the power cabel wich supplies the organ and leslie with power.

I will try tapping the signal of from the AO28 preamp. I ordered replacement caps and resistors for the AO28 and for the 145 crossover. I also noticed a unpleasant overdrive wich is coming from the v21 (not from the basspeaker) i think the crossover is causing this but i will try my other v21 driver.

Hope this is more clear :)

Cheers Boye

[model D]

If you think the crossover may be the culprit, it may be better to resolve before swapping in another compression driver...

[nonreverb]

I've found in my experience that the crossover is usually not the problem. The driver is. They're notorious for sounding like a kazoo if/when the coil gets misaligned.
Boyan is correct in that the overdrive sound you hear probably is the coil buzzing. You can try adjusting the coil if you wish but the caveat is, it's a tedious exercise and is not always successful.

[boye]

If you think the crossover may be the culprit, it may be better to resolve before swapping in another compression driver...

I have the v21 just laying around and i am sure it is working properly so that wont be a big deal to try, but still, i have ordered the Crossover caps so i will curtainly install them. Also for adding lifetime to the leslie :).

I've found in my experience that the crossover is usually not the problem. The driver is. They're notorious for sounding like a kazoo if/when the coil gets misaligned.
Boyan is correct in that the overdrive sound you hear probably is the coil buzzing. You can try adjusting the coil if you wish but the caveat is, it's a tedious exercise and is not always successful.

Ah okey, i understand. Before i am going to adjust the coil i will first try my other v21! If indeed it is the coil, I will try adjusting the coil. If that is without succes I think a replacement driver is needed.

Thanks for both your advice!

Boye