Leslie 122 Distortion

[Brent Watkins]

Hi All,

Just got my Leslie 122 connected to an A-100, and am having some issues with cracking/distortion coming from the horn. It actually sounds pretty clean when I'm only playing high notes, but, for instance, a low-mid range note, like F# 2 really makes it grind. This is when I'm only working at about 50-60% volume. Does this sound like a normal problem? I checked for loose connections, but everything seems pretty tight. Thanks for your help.

Brent

[tonewheel1966]

Before you blame the Leslie, have you tried clipping headphones to the GG terminals to see if it comes from the organ?

I thought I had this problem earlier in the year but it is just Hammond characteristic crosstalk and rumble. The higher notes are filtered. If you play a 888000000 registration in the middle octaves do you get that sound? I played my clone through the Leslie and got the same effect. If you play along toa music CD you won't notice it.

It took me a preamp, Leslie amp and tone generator recap to realise this [:$]

Also is your tone generator wax capped?

Cheers

Dave

[Brent Watkins]

Hi Dave,

Thanks for your response. Forgive my ignorance . . . . which exactly are the G-G terminals? The organ sounds generally OK through the internal speakers, so does this rule out a problem with the organ? I've been through just about everything on the leslie, and can't make sense of it, so maybe it's the organ. It doesn't do this at very low volumes, but once I start turning it up the buzz shows up. Mainly through the horn, which is strange, because I know my horn driver is fine. It's just that low-mid range stuff that brings out the distorted sound. Otherwise, the high notes scream at a loud volume, with no distortion.

Brent

[tonewheel1966]

I think it's just crosstalk-more pronounced on wax capped organs without the r/c networks. If you download the B3/C3 manual there is a chart in there showing the tones used for each key and drawbar. I highlighted the filtered tones and then worked out where the split on the keyboard for each drawbar was. Everything above the split sounded good, and everything below had the fuzz which means crosstalk. You don't hear it on recorded hammonds it's just one of those things you notice when you're on your own playing one. I still get some on my recapped Hammond. It's just part of the character. I think Leslies show it up a bit more than the internal speakers.

The GG terminals are the balanced outputs on the preamp terminal strip (with a G stamped over both of them, next to the ground tab).

What year does the organ date from?

Cheers

Dave

[geoelectro]

Did you replace the Leslie filter cap? A bad second stage will cause distortion at medium volumes.

Geoelectro

[Brent Watkins]

Not sure, as I just got the leslie. Are the caps in the amp, or the crossover?

[geoelectro]

In the amp. A 4-section can with 30, 30, 30, 10 MFD @ 450Vdc. The second stage (30Mfd) filters and stiffens the supply to the output tubes. Just fixed one today. Connect a meter and set to read AC volts. It should read under 1Vac. Play some notes. It should not rise over 1Vdc. if it does, change it. This info and more detail caqn be found on my site, www.bentonelectronics.com/leslieamp.html

Geoelectro

[Brent Watkins]

OK, now here's the stupid question. How do I get this thing out? Do I just yank it out? Better to ask than to break something. It's the exact same amp as the one for sale here: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&Item=180444324448&Category= 16219&_trkparms=algo%3DLVI%26its%3DI%26otn%3D2#ht_ 500wt_1137

So reaching back into the leslie and trying to get it out seems a little tough. I'm sure it's easier than I'm making it, but I want to be sure. Thank you for your help.

Brent

[geoelectro]

Unplug the cables remembering where they go. Take out the ONE screw on the middle of the front plate that screws into the bottom of the cabinet. Pull the amp out. That's it![H]

Geoelectro

[tonewheel1966]

[quote user="geoelectro"]


Unplug the cables remembering where they go. Take out the ONE screw on the middle of the front plate that screws into the bottom of the cabinet. Pull the amp out. That's it![H]

Geoelectro

[/quote]

Much easier than doing the AO28 cans