Reuben Wilson at the B3

[The Magnificent Goldberg]

I just started listening to "The Godfathers of Groove" by Reuben, Grant Green Jr and Bernard Purdie. This photo appears in the insert.

Wow! What about that!

Oh, the album sounds great so far!

MG

[Joe G]

You mean the innards? Yep, lots of wires and stuff.

[jazzbo]

I wonder if anyone ever really put quality amplification in a B3. .. Not that the stock doesn't do the job admirably, but better chassis, transformers, resistors and capacitors, the best possible tubes. . . ?

Edited January 31, 2007 by jazzbo

[Jim Alfredson]

It is common practice to replace all the capacitors in an old Hammond since they can range anywhere from old wax capacitors (which dry up and change value) to paper ones that are not much better. Putting military grade Sprague caps does make a difference. I did it to mine, although I did not mess with the preamp, I only changed the tonewheel generator caps. But it made a profound difference. Much cleaner highs, much more even tone across the keyboards and drawbars, and much easier to get that gnarly overdriven sound.

Resistors haven't really changed all that much in the last 50 years. Sure, you could put higher tolerance ones in, but I doubt it would make much of a difference.

As for the tubes, they are usually old RCAs, which sound better than anything you can buy nowadays. The preamp does not drive them hard, so they last forever in that circuit. No need to replace.

I try hard as I can to put NOS RCAs or Tung Sols in my Leslie preamp, since they sound so good. The new tubes of today cannot compete.

The preamp is actually very well designed and uses very good transformers. Keep in mind that the Hammond is hardly a "hi-fi" instrument. The top of its range only goes to 6kHz or so, so there's no need for a wide frequencey response. In fact, some of its charm is in the filters and volume control that are anything but h-fi.

Btw, if you want to see crazy inards, you should see the inside of my Hammond BCV! Maybe I'll take a pic.

[Jim Alfredson]

Ok, here you go, the insides of a Hammond BCV circa 1940.

The lineage of the B series goes Hammond BC, Hammond BCV & BV, Hammond B2, Hammond B3. If you see an old Hammond A (the first model, not the A-100 series, but just plain "A") the first thing you'll notice is that the case is physically less deep. They increased the depth of the case for the BC. Why?

In the picture you can see a long metal box with all these metal "knobs" sticking out. That's the tonewheel generator. That where the sound comes from. It's a bank of 92 discs spinning at various speeds with various amounts of teeth on them. Above each one is an electromagnetic pickup, much like a guitar pickup. As the wheels rotate at various speeds, they create a disturbance in the magnetic field of the pickups at a steady rate, thus creating a sine wave of a certain pitch (depending on the speed and the number of teeth). In the picture of Reuben, the tonewheel generator is behind the preamp (the thing out in front with the tubes and transformers on it). Starting from the B2s, Hammonds had one tonewheel generator.

The BC's actually has two complete tonewheel generators in it. The one you can see in the picture is number one, and directly behind it is another. Why? Because Hammond hadn't yet figured out how to create the chorus effect electronically, and so they expanded the A-style case (increased the depth) in order to add another entire tonewheel assembly that was slightly detuned from the primary tonewheel generator. When you add the two signals together, you get a chorus effect. Later, they figured out how to do vibrato electronically with the aid of a scanner system (and soon chorus, too) so they started making the BV's which had chorus and vibrato and offered a retrofit kit to add vibrato to older BCs. The vibrato line is that silver box up at the top. It consists of inductors and resistors.

When they started doing chorus electronically as well, they dumped the second tonewheel generator, but kept the cases for the organs the same dimension (since they already had a bunch made). That's why there is so much empty space in the back of Reuben's B3 as compared to a BCV. The electronic chorus/vibrato system became much smaller, too. On the B3 pic, it is attached to the back of the upper manual, in the upper left corner. You can see a row of capacitors (they look like little teeth in that shot, standing straight up). Much smaller than the big long silver box in my picture.

The BCV also has more tonewheels per generator than the B2s and B3s. That's because it does not have octave foldback. But that's a discussion for another time.

More information than you ever wanted to know!

[Robert J]

But where's the MIDI out?

[Man with the Golden Arm]

thanks for all that info, Jim! there is such great stuff on this board to allow us "listeners" to really appreciate the work.

aside - a couple nights ago a local channel's magazine show called "Chronicle" featured a bit of "made in new england" and visited the C.B. Fisk Company up in Gloucester, MA. it was quite an eye and ear opener.

so... when you guys play the east coast you'll need a tour!

[Soulstation1]

http://www.tonewheelgeneral.com/agelist/agelist.php

GREAT site for hammond info

[Jim Alfredson]

thanks for all that info, Jim! there is such great stuff on this board to allow us "listeners" to really appreciate the work.

aside - a couple nights ago a local channel's magazine show called "Chronicle" featured a bit of "made in new england" and visited the C.B. Fisk Company up in Gloucester, MA. it was quite an eye and ear opener.

so... when you guys play the east coast you'll need a tour!

That's sweet! I got to see the Wanamaker organ while in Philly a few weeks back. Over 29,000 pipes! Holy crap!

[The Magnificent Goldberg]

Ok, here you go, the insides of a Hammond BCV circa 1940.

The lineage of the B series goes Hammond BC, Hammond BCV & BV, Hammond B2, Hammond B3. If you see an old Hammond A (the first model, not the A-100 series, but just plain "A") the first thing you'll notice is that the case is physically less deep. They increased the depth of the case for the BC. Why?

In the picture you can see a long metal box with all these metal "knobs" sticking out. That's the tonewheel generator. That where the sound comes from. It's a bank of 92 discs spinning at various speeds with various amounts of teeth on them. Above each one is an electromagnetic pickup, much like a guitar pickup. As the wheels rotate at various speeds, they create a disturbance in the magnetic field of the pickups at a steady rate, thus creating a sine wave of a certain pitch (depending on the speed and the number of teeth). In the picture of Reuben, the tonewheel generator is behind the preamp (the thing out in front with the tubes and transformers on it). Starting from the B2s, Hammonds had one tonewheel generator.

The BC's actually has two complete tonewheel generators in it. The one you can see in the picture is number one, and directly behind it is another. Why? Because Hammond hadn't yet figured out how to create the chorus effect electronically, and so they expanded the A-style case (increased the depth) in order to add another entire tonewheel assembly that was slightly detuned from the primary tonewheel generator. When you add the two signals together, you get a chorus effect. Later, they figured out how to do vibrato electronically with the aid of a scanner system (and soon chorus, too) so they started making the BV's which had chorus and vibrato and offered a retrofit kit to add vibrato to older BCs. The vibrato line is that silver box up at the top. It consists of inductors and resistors.

When they started doing chorus electronically as well, they dumped the second tonewheel generator, but kept the cases for the organs the same dimension (since they already had a bunch made). That's why there is so much empty space in the back of Reuben's B3 as compared to a BCV. The electronic chorus/vibrato system became much smaller, too. On the B3 pic, it is attached to the back of the upper manual, in the upper left corner. You can see a row of capacitors (they look like little teeth in that shot, standing straight up). Much smaller than the big long silver box in my picture.

The BCV also has more tonewheels per generator than the B2s and B3s. That's because it does not have octave foldback. But that's a discussion for another time.

More information than you ever wanted to know!

Jim, that was a much clearer statement of how a Hammond actually works than I've ever seen. Thank you so much.

MG

[ghost of miles]

He was just here at the station! Signed my copies of LOVE BUG and BLUE MODE... all three of them were really cool and fun to talk to. Showed Mr. Wilson a picture from this thread & told him there was much positive discussion going on here... he was very pleased. (And he now knows who Organissimo is, too!)