Leslie 122 amp - doubling the power?

[b3groover]

As many of you know, I'm a Hammond B3 player. I travel with a 1958 Hammond B3 and 122 Leslie. The Leslie 122 amp has two 6550's in it, so it puts out about 40 watts or so. A lot of times on the gig, this is not loud enough. Actually, I don't really want more volume, I just want to be able to push it a little harder without it breaking up. Since I kick bass, there isn't a lot of headroom before the distortion kicks in.

Looking at the schematic:

http://www.captain-foldback.com/Leslie_sub/Leslie_schematics/122.GIF

Would there be a way to maybe add two more 6550s to the circuit or would it be more trouble than it's worth?

 

[NewYorkDave]

You'd have to replace the output and power transformers, essentially rebuild the amp into something completely different. And at the end of it, you'd only be 3dB louder. Really not worth the trouble. You'd be better off using a different amp if you need to increase the power substantially. And can the drivers in the cabinet take the extra power, anyway?

You could get a bit more clean output from the existing circuit by going to fixed bias on the output tubes, but I'm assuming you want to retain the basic character of the amp, part of the "Leslie sound." If volume and headroom were the only objectives, I'd say install high-power drivers and use a Crown power amp :wink:

 

[b3groover]

One thing I've read about is using the stock Leslie amp to power only the horn and then using an outboard amp (like a Crown... anything really) to power the bass. That may be the way to go.

Thanks.

 

[NewYorkDave]

Yeah, use a line-level crossover before the two amps and remove the passive "dividing network" from the cabinet. Sounds like a plan!

 

[b3groover]

Where can I find high-quality, octal tube sockets? The 122 amp in my Leslie is a modern re-creation made by Hammond-Suzuki and one of the pins on a 6550 socket broke off completely. On the gig of course. I jury-rigged it with a piece of wire but I need to replace the socket with something high quality that won't break.

Amazing isn't it? I have Leslie amps that are 50 years old and the sockets on them are fine.

Also, what are the best sounding 6550 tubes? I need to replace mine as well.

 

[NewYorkDave]

I haven't bought any sockets in a few years; but when I did, my preferred source was
www.newsensor.com

As for 6550s: I haven't kept up with the latest 'n greatest, but as of a couple of years ago, the best current production were Svetlana. Whatever you do, stay away from Chinese!

 

[SSLtech]

I had the fun task of workingon John Lord's leslies a while ago. He was to get over Richie Blackmore's backline (just for him to hear himself onstage!) so his are a bit tricked up. -Probably more that yours needs to be, but here's a quick summary of what was done to his.

The C3 (his is the console version) goes line-level out, to some effects pedals (that way he can footpedal-on/off distortion etc) then the line level output goes to a xover/amp rack. The signal first meets a 2-way crossover. The highs go to a big-ish amp, the lows go to a B-I-G amp. Both were Crown 'Macrotechs', if I recall correctly. The stereo amps are fed mono to both channels. Each high output goes to the horn of each of two Leslies. (One offstage for miking without too much spill, one near to John so that he can sense things like rotor inertia etc...)

The horns were replaced with JBL 2482's (2", mad power drivers capable of unleashing instant electric death) and the woofers were replaced by mad bastard PA 15's.

Since the SPL output of the leslies was increased so dramatically, they started to shake themselves to pieces and develop rattles, so unneccesary stuff (like the old amps) were removed for safe keeping, and the wood joints were re-glued, sealed and caulked to a mad degree. They have to survive bouncing in flight cases as well as teeth-jarring vibration from monster woofers, after all.

This is way more than you're talking about, but you really do have to start considering cabinet stiffness and joint integrity if you significantly increase the SPL output...

By the way, I was in Nashville on cinco de Mayo this year, I helped put yet another Amek 9098i in for a friend, and he took me out for a beer afterwards. We pulled into the parking lot of the bar at about midnight, and I saw the license plate "B3 PLAYR" on the van in front of us. -I often hate having a band on when I'm out for a social beer with friends, but this night was fantastic. -I don;t know who the band was, but it was based around this B3 player who was pretty friggin good at his craft. -I LOVE a good B3/C3 craftsman, and I bet I'd dig your gig as well. -If fate ever finds you behind the twin manuals in Florida, let me know!

Keith

 

[b3groover]

Keith,

We played the Clearwater Jazz Holiday back in October of 2003. We hope to get back to Florida again soon.

I don't need ear shattering loudness, just a little more headroom. I think my Leslie has a Peavey horn in there right now (which actually sounds good, believe it or not) and the stock woofer, so all I'd have to do is buy a new woofer. I have a crossover, I have a line-level output on the organ (custom made direct box) and I have a power amp just sitting around so I'm almost there.

The big thing I'm worried about is losing the tone of the Leslie. Even with that Peavey driver, I get compliments all the time on how ballsy my rig is. It would be a shame to lose that, but I guess it doesn't hurt trying.

 

[SSLtech]

...you know, Jon Lord used Peavey Black Widow 15's for a while...

With them and the 2482's, you could hold up a bank... "nobody move, or I play an Emin7+9"!!!!

:green:

Definately let me know if you're back round central Florida.

Keef

 

[Underthebigtree]

B3groover - an interesting topic, and one that is near and dear to my organ playing heart.

Anyway, I spoke about upping the power on my gigging 122 to the West Coast's unquestioned Hammond guru, Bob Schleicher. He said that making the 122 louder than it was designed to go radically changes the tone (and not for the better).

Personally, I find that having the 122 3-4 feet behind my head at a gig, with volume wide open is well enough to take my head off. But I don't kick bass (I use a chop with no pedals for gigging).

Couple things I did that made life a lot better:

1) I permanently mounted 4" casters to the bottom of the 122.
2) I added recessed handles to the sides - this makes it MUCH easier to pick up and load into a van after the gig.
3) I permanently wired an SM 57 into the upper rotor area, and an Audix kick drum mic with extra internal windscreen in the lower rotor area. These are wired to a pair of XLR jacks on the outside of the cabinet. Sound men can never say "Oh, I don't have enough mics" or "I'm out of stands". They just plug to XLR cables in, and I'm good to go. This approach might help you, as they could route a bit of 122 back into your monitor.

One last idea - I experimented with various tube flavors to get different levels of distortion out of the 122. I don't remember exactly which ones were which - it's been several years now. But off the top of my head, I seem to remember replacing the 12AU7 with a 12AY7, a 12AT7 and a 5751. The 12AY7 added a pleasing bit of grit at low volume levels. The 12AT7 was pretty distorted - very Jon Lordesque. And the 5751 was shrieking, paint peeling Marshall stack nastiness. I ended up sticking with the 12AY7.

Always good to talk to another of the Hammond bretheren. Check out my site if interested - www.underthebigtree.com. Happy holidays - Nick

 

[b3groover]

Nick,

Cool site! That bloody Hammond picture brought back memories!! I haven't broken a key yet, but about two years ago in the summer I was playing an outdoor hit with the R&B band I play with. The gig went fine, but I had another gig to play that day over an hour's drive away so I packed up my rig as fast as I could and proceeded to JAM my left thumb into the corner of the Leslie while moving it. Bent the nail all the way back, hurt like a motherfucker!

So I drive to the hit and on the way the bleeding finally stops. We load the beast on stage and I start to play bass (I use the Jimmy Smith style... a combination of left hand and foot pedals) and of course the wound on my left thumb opens up and I bleed all over the fuckin' lower manual. Luckily we only hit for 45 minutes and were done.


Concerning the Leslie, I have mics that I've been meaning to mount. I also have casters on the Leslie, permanently attached. The recessed handle idea is a goodun' though.

If I had more room in my van I'd haul another Leslie. It's amazing what one more Leslie will do. I used to rent my B3 to a club whenever Joey DeFrancesco would come to town. The first time I only had one Leslie for him so he wound up using a bass amp that just happen to be at the club and wired it off the preamp outputs. He played loud as hell and my rig sounded like shit.

The next time he came into town I brought two Leslies for him. He played softer and the bass just filled up the room. So it's not necessarily about volume, it's just about having that nice solid low-end.

Nowadays I'm using the direct line off my Leslie to go into our sound-system, which has a nice big Yorkville sub. So I get plenty of bass, actually. What I'm missing now is the subtle high-end key-click. Maybe I should just go with some in-ear monitors. The organ is definitely loud enough through the sound system.

Ideas ideas.

----Jim

ps. My site was probably down this evening. The server is based in Cincinnati which got it's assed kicked by that storm. It's back up now if you'd like to hear the trio in action.

 

[Scodiddly]

Maybe for a start you could try a regular PA sub on a regular power amp, just to beef up the pedal tones. Might even be nice to have the absolute bottom "spin free".

 

[b3groover]

[quote author="Scodiddly"]Maybe for a start you could try a regular PA sub on a regular power amp, just to beef up the pedal tones. Might even be nice to have the absolute bottom "spin free". [/quote]

Ah but Scott your syncrotor rocks! I actually used to take the direct box out into an amp and a Yamaha cabinet with a 15" woofer in it and that did fairly well with the bass. It was more for our drummer, so he could hear the bass more clearly.

Now with the sub on the soundsystem, bass isn't necessarily a problem. The problem is that the Leslie amps breaks up a lot sooner than I'd like. I think it breaks up sooner than an older 122 amp (this is the Hammond-Suzuki remake, remember). In fact, anything over 6.5 on the dial of the amp is basically useless. It's just distortion. When I'm playing with the R&B band and not kickin' bass, it's plenty loud.

I just want to be able to hear that nice Hammond key-click and have more headroom before breaking up.

 

[Scodiddly]

Still using the Syncrotor? Wow - those things are hard to kill, although I've gotten a couple of calls from Decker about the one in Japan dying. Always the dual op-amp that handles the switch input... I suspect somebody kept trying to run a signal into that jack. :roll:

Ya know, people used to sometimes just build an external motor control (which you have!) and then plumb a nice loud guitar amp in place of the stock Leslie amp. A Fender or Ampeg tube head would work (if OK with 16 ohms), since those are fairly conservative designs with flat outputs.

 

[PRR]

> I permanently wired an SM 57 into the upper rotor area, and an Audix kick drum mic with extra internal windscreen in the lower rotor area. These are wired to a pair of XLR jacks on the outside of the cabinet. Sound men can never say "Oh, I don't have enough mics" or "I'm out of stands".

I can still say "I'm out of inputs and cables." (I'm a 6-input kinda guy, so it might be true.)

Rig a mixed output. Your levels are PLENTY high, so it can be a passive mixer. And you can set YOUR blend yourself, even adjust it on stage, rather than be at the whim of some failed bass-player who mixes all thud and no horn. Have a switch to go back to the split outputs in case you do play a gig where the sounddood has a clue and taste.

 

[peterc]

Hey B3

If you're only looking for a bit of extra top end & can't carry an extra Leslie, what about adding one of these to your existing rig :

http://www.motion-sound.com/pro-3tm_&_low-pro.htm

Just the horn, obviously.

I dont know what they sound like, but they look quite interesting.

Regards
Peter

 

[b3groover]

Those are cool. I've used one before but only with Hammond clones. I think my best bet is to get some in-ear monitors and make my own mix.

Speaking of Motion Sound, this baby looks sweet!

http://www.motion-sound.com/ms-1771.htm

200watts!


Scott, I love the syncrotor! In fact, I kind of need another one, but I want to use it on my 21H which only has single speed motors. Either I have to replace the motor or get one of those kits that convert the single-speed motors into double-speed.

 

[Scodiddly]

[quote author="b3groover"]
Scott, I love the syncrotor! In fact, I kind of need another one, but I want to use it on my 21H which only has single speed motors. Either I have to replace the motor or get one of those kits that convert the single-speed motors into double-speed.[/quote]

Yeah, that's the tricky part. Would be cooler to make a new syncrotor based on a microcontroller instead of discrete logic, and build in the slow motor stuff at the same time. Not sure if I want to get into that stuff at this point, though, since I've never really found it that interesting.

I think I do have either a new or a rebuilt syncrotor just sitting in a box, though. That stuff comes up so rarely I have to learn it all over again when somebody wants one.

 

[Gus]

People some of the stuff I work with use AC drives up to 100HP and under 1hp. Look up PLC and AC drives. The drives have all kinds of ways to be controlled some even have onboard controllers with PID built in you should only need the PI part from a lookup table.

It sounds to me you will need to build something. The motor drive stuff should be easy with todays controls. If you go microcontroller you can have all kind of stored spins rates etc you might even be able to make the horn and woofer part move side to side or one side to side one rotating etc. if you use a encoder and a toothed belt.

There are even high power steppers.

To me the problem would be making the cab light enough and able to handle high power. Some modern drivers can handle high power. Take Crown PB3 or macrotech(like Keith posted) or a SVT if you want tubes and a crossover and that parts done. Making a cab that can fit in a vehicle and be able to move is the hard part.

 

[Underthebigtree]

Jim, I just checked out your website. Great band name (one of the hardest things to get right!) and, more importantly, terrific music.

More power to you! It makes me so happy that us younger cats are out there keeping the tradition of jazz organ alive.

Cheers to all,

Nick