String Bass Effect and MIDI on a C2

MIDI.

Adding MIDI capability is perhaps the most profound addition that I have made to this C2. MIDI allows playing among other things a modern electronic keyboard from the keys and pedals of the Hammond, and also of having a different effect on each. Whereas generally a keyboard produces only one sound at a time from its one keyboard, MIDI actually operates on 16 different channels. If you have your keyboard's layer function on, then it is using two MIDI channels. Likewise if you use the keyboard split function, this also uses two MIDI channels. And if you have both the layer and the split functions in use, then the keyboard could use three channels. But you trade off because if you split the keyboard, then you have effectively two keyboards, but they are both smaller, because you can't have any more playing keys than your keyboard was designed to have. Yet another MIDI channel (generally channel #10) is dedicated to rhythm. Therefore, when we add MIDI capability to an otherwise non-MIDI instrument, and that instrument has more than one keyboard and also pedals, then each keyboard and also the pedals can control a different MIDI channel, which gives us many interesting possibilities.

Although the traditional Hammond organ could produce many different tonal effects, it lacked certain useful sounds, and Don Leslie was only one of many people and companies that began to make things that could be added to a standard Hammond organ to improve its range of musical effects. One such company was Maas-Rowe who are noted for their amplified chimes and bells, such as the Vibrachord and the VibraChime. Many of their units have been sold to churches, and also many churches bought recorded arrangements of well-known hymns and Christmas music, played on both of these instruments and which they could play over their tower speakers, and likewise, many individual musicians and commercial enterprises that used Hammond organs would also buy these units and Maas-Rowe had by then developed kits which included key contact assemblies that could be installed in Hammond organs. No doubt Laurens Hammond probably didn't like Maas-Rowe either, as well as not liking Don Leslie, although that is an assumption on my part and must be understood as being my opinion and not proven fact.

Both the Vibrachord and the vibrachime are relatively big and heavy instruments; both contain suitably shaped and tuned steel rods or bars which are struck by solenoid-activated strikers, and also have a magnetic pickup close to each bar. The vibrachord can imitate quite accurately the sound of vibes, or a glockenspiel, and it includes an adjustable amplitude-varying tremulant. From examples I have encountered, it consisted of either a small keyboard, or a set of key contacts, and a separate enclosure for the steel bars. The vibrachimes that I have seen were self-contained in a wood cabinet which also had a small keyboard included. If you decided to add it to a Hammond organ, you could either attach the Maas-Rowe keyboard to the Hammond, or you could buy a set of special contacts to place under the keys of either manual. From those Maas-Rowe instruments that I have encountered, I must say that they are really nice, and do indeed add a great deal to the capabilities of a Hammond organ that includes these Maas-Rowe instruments as part of the total package.

Then of course there was the Kruger string bass accessory which came with a box for the electronics and also a set of 18 contacts that you would mount under the pedals. Why they stopped at note 18, which is the second F, defies logic, but I guess they figured that the majority of Hammond users were one-foot pedalers who rarely if ever got above F. I had heard that the late Eddie Layton had two Kruger basses on one of his instruments so that the second one would handle pedals F# through top C. But this is an unconfirmed rumor although it would make sense considering how good a musician he was.

However, now that we have MIDI, realistic chimes and vibes and glockenspiels are only one of hundreds of really great effects that can be played from a suitably-equipped Hammond organ, and it is no longer necessary to have big separate assemblies or wood cabinets connected to separate sets of extra key contacts with their attendant multi-wire cables; but I mention all of this to point out that almost since its inception, certain individuals realized areas in which the basic Hammond was deficient and developed various ways to overcome these deficiencies, thwarting Laurens Hammond at every turn as they cleverly overcame the difficulties he created for those who wished to augment a typical Hammond instrument.

In addition to standard electronic keyboards, there are other MIDI devices as well. MIDI sound modules are essentially like an electronic keyboard without the keyboard. They generate standard MIDI musical instrument sounds but are intended to be played from other, separate keyboards, or even from sequencers and computers. Likewise, there is MIDI capability on a typical computer sound card, so a Hammond organ that is equipped with MIDI can also play the sounds that are in a computer sound card. And the beauty of this is that the Hammond organ is still a Hammond organ, so that all of the nice Hammond sounds which we know and love are also available to be used individually or in combination with the MIDI sounds.

Because the instrument sounds that modern MIDI instruments produce are sampled or modeled on the sounds of real musical instruments, the instrument imitations which you get from most MIDI devices are extremely accurate and very authentic. Whereas most electronic organs, particularly a traditional Hammond use an entirely different technology which creates sounds from certain basic tones, MIDI instruments give you actual [recorded in a sense] tones of real instruments. When you play a MIDI grand piano sound, for example, unless you see what is being played, you could very easily think that you are hearing a real piano. Likewise, the tone of a saxophone defies imitation by analog electronic organ technology. For that matter, it defies imitation by organ pipes also. But when you use a MIDI instrument to produce the sound of a saxophone, it really does sound like a real saxophone. Therefore, when you add MIDI capability to a Hammond organ, you give the keys and pedals of the Hammond the capability of playing MIDI sounds which means that you will now have the capability of playing extremely authentic musical instrument sounds.

A keyboard which plays a MIDI sound source is generally referred to as a MIDI controller. Therefore, a typical electronic keyboard is both, a MIDI controller and a MIDI tone source in the same package. What I have done is to turn this Hammond organ into a two manual + pedals MIDI controller, and at the same time, it is still a Hammond organ. So the Hammond organ is not directly producing anything other than its normal Hammond sounds, but it now has the ability to play a MIDI device as well; the combination of the two then becomes greater than the sum of its parts in that the MIDI tones can enhance what the Hammond organ does, and likewise, the Hammond organ as a MIDI controller gives us all the great musical instrument sounds of a modern keyboard, and allows us to exploit that keyboard even more in that we can access different sounds from the keyboard on two manuals and pedals. So what is involved to make this happen?

The overall description sounds really simple. You add one extra key contact under each key of the Hammond; likewise for the pedals, although in this case, I chose to use one set that was part of the original Hammond pedal switch. These get connected to MIDI multiplexing cards which in turn feed their outputs to a MIDI encoder card. The MIDI encoder card then sends all of the resulting MIDI information to the MIDI sound source, which in my situation is presently a Casio keyboard. As you may infer from the above, MIDI information is not music. MIDI information consists of instructions that are interpreted by the MIDI device which receives these instructions which then, in following the instructions, generates various music instrument sounds which get amplified and sent to speakers. So as far as the over-all or big picture is concerned, it's pretty simple.

Enter Laurens Hammond! As I already mentioned, Laurens Hammond may very well have had a tremendous ego. He really felt that what he and his people developed could not be improved. Furthermore, as exemplified by the way he treated Don Leslie when Leslie approached him about his Leslie Speakers, he turned against people who came up with ideas that could improve the sound of Hammond organs. We read that at musical instrument conventions, Hammond instructed his minions to throw Leslie out if he showed up at Hammond's exhibits. He tried on several occasions to "Leslie-proof" Hammond organs so that you could not connect a Leslie speaker to a Hammond. Of course Leslie was no slouch in the brains department, and easily circumvented Hammond's "Leslie-proofing" and after Laurens Hammond was gone, the Hammond Company did indeed incorporate built-in Leslies into many of their later production instruments. But this tells us a lot about why making additions to traditional Hammond organs is difficult at best. However, it can be done, and although Hammond also "Larson-proofed" his instruments, [Even though I was just a kid during his peak years at Hammond Organ] I nevertheless figured out how to add the necessary extra key contacts to a traditional Hammond organ to add MIDI controlling capability. It was not easy. But it was not impossible either! We may also say that Hammond "George Wright-proofed" and "CBS-proofed" and "Joe Bucci-proofed and "Eddie Layton-proofed" and indeed made it difficult for anyone to add anything of significance to a Hammond organ. But difficult and impossible are very different, and we all prevailed!

The first step in adding MIDI capability is to add an extra set of key contacts, unless you want to sacrifice one drawbar per manual. While I didn't mind getting rid of Hammond's horn-like pedal tone, I did not want to sacrifice any manual drawbars at all, thus I opted for adding one set of extra contacts to both manuals of the Hammond. Since he left no room for contacts under the keys, at least not contacts supplied by others, I made my own. For ease of fabrication and installation, I made printed circuit cards to hold my contacts, which consist of #28 gage silver wire for the contacts and 22 gage silver wire for the bus bar. Silver is excellent for contacts because even when it tarnishes, silver oxide is also a good electrical conductor, so this means great reliability. The silver wire that I used is actually called coin silver, and it is a mostly silver alloy that is also quite springy, which is a necessary property for a key contact to have. There are cheaper alternatives, but silver wire seems to be best. That it is the contact material of choice for just about all electric action pipe organs and other such instruments as well as applications says a lot. Here is a look at my key contacts during installation. The reason for bending the tips of the contacts back so that they somewhat resemble candy cains is to give two contact points for added reliability.

As you can see, adding MIDI to a traditional Hammond tonewheel instrument is not a quick or easy Saturday-afternoon project. Making your own printed circuit cards is an involved procedure by itself, although there is much information on-line about this topic, and there seem to be almost as many methods to use as there are people who do this. But there are several methods for do-it-yourself printed circuit card fabricating that are considerably better than others, and because I had already devoted a lot of time and research into this activity, the results I obtain in PCB fabrication are now excellent. But I mention this to point out that as a complete project, if you include all attendant activities and procedures, the addition of MIDI to a standard Hammond organ is a major undertaking, and it also requires a great deal of patience and care, because it does entail a high degree of risk of doing permanent damage to the Hammond organ unless you are really careful and pay lots of attention to the many details involved. However, at least in my opinion, the musical rewards that I, as a Hammond player gain as a result of having MIDI capability on a traditional Hammond organ are worth all of the effort.