Modifications Plus

Some of the stock Hammond features are normally inaccessible to the player.  ProKeys can modify most Hammonds to allow:

Continuously variable CHORUS control - this is a simple potentiometer, mounted near the player, which allows control over the amount or depth of the chorus.

TONE control - we re-mount the Hammond tone control in a location which the player can use, rather than hidden inside the organ on the AO28 preamp chassis.  To retain the classic Hammond sound, nothing is changed in the stock Hammond tone circuitry.

PERCUSSION control - we re-mount the percussion control in an area that is accessible to the player, instead of the stock location on the AO28 preamp.  No circuit changes are made, so the original Hammond percussion sound is not altered in any way.

REVERB can be installed in most Hammonds.

Generator shock mounts are highly recommended for any Hammond which is used professionally.  We install only the best - GOFF Professional shock mount kits.  These kits install once, and will protect your generator properly, without the need to lock and release it at every gig.

PREVENTATIVE modifications - certain areas of Hammonds and Leslies seem to wear out or fail at exactly the wrong time.  We try to anticipate some of these possibilities, and suggest replacements or repair beforehand.  A few examples:

        - Replace the stock Hammond start and run switches with a much heavier duty grade.
        - Install a solid state power relay.  Read about it.
        - Install 110v line fuse in the AO28 preamp.

Hammond Power Supply - Outdoor gigs often use power generators.  These can cause pitch problems.  Read about it.

Hammond and Leslie Tubes - We keep a fairly good supply of tubes on hand for AO28s and Leslie amps.  Each tube is thoroughly tested on a calibrated, commercial Hickok 539C tester and a Fluke 87 Series III digital meter.  We test and grade for shorts, heater-cathode leakage, transconductance, plate current, and several forms of gas leakage.  This superb tester allows us to select the best tubes for a matched set.  Critical test result values are marked on each tube.

Tube suggestion:   Test and select your tubes carefully.  Balanced tubes really help the overall sound.  Many tubes (12AU7 preamp tubes for example) actually contain two separate sections.  If the sections are out of balance, it can show up in the amplification stage.  In some cases, (Leslie switching 12AU7, for example), only one half of the tube is used.  After awhile, these tubes are no longer balanced for correct preamplifier use.

TRANSPORTATION DETAILS - Often overlooked are the tools needed to transport Hammonds and Leslies safely.  ProKeys is very concerned with your equipment being roadworthy, and surviving a life of constant use and moving.  Some areas to consider are:

Roll-Or-Kari (ROK) moving dollies - Specifically set up for B3 width, with all swivel casters.  These ROKs are brand new, and built to last forever.  We devised a unique belt modification, featuring instant snap on/snap off closures, requiring no belt threading.  This modification simplifies the strapping process, and reduces strapping time by about 90% or more.  Once you've tried it, you'll never want to use the old belt threading style again.  Blue polyurethane tread casters are available, rated for 125 lbs. each, as direct replacements for the hard casters supplied with ROKs.

Leslie caster kits - Casters are mandatory for working musicians.  Our caster installations use the best quality 1" wide, 3" grey thermoplastic rubber treads on grey polypropylene wheel cores, rated at 100 lbs. per caster.  Blue polyurethane treads are also available, rated for 125 lbs. each.  Two swivel, two are rigid.  Brakes are also available for the swivel casters.  Mounting is via threaded steel inserts, sealed and locked to prevent vibrating loose.  These are true professional casters, not like the ones you find in a hardware store.

Hammond and Leslie padded moving covers will protect your investment, and are highly recommended.  We offer several different grades, weights, and styles.  Custom covers in many different configurations are available.

Appearance - We've set up some Hammonds and Leslies to look really beautiful, even though they're road or gig organs.  Rather than refinishing in a mirror finish, the wood is stripped, sandblasted, and sanded lightly.  Many, many coats of Tung oil are applied over the open, natural wood, without any filler or stain.  Tung oil dries to a very hard finish, and looks excellent.  It's available in a high gloss or semi gloss finish, but will not have the mirror look of hand rubbed lacquer when complete.  However, the true benefit of this type of finish is, the inevitable scratches and nicks can be touched up just by wiping some Tung oil on them.  Filling, staining, sanding, and final coating are not necessary.  We highly recommend this treatment for road Hammonds and Leslies, to keep them looking truly beautiful for many years.

click picture for fullsize view

In July, 2000, we tried another option for refinishing.  As above, we stripped and sandblasted three ProKeys Leslie cabinets, very lightly sanded them, and applied 9 coats of PPG Omni AU, a two part, very hard automotive clear finish, using a commercial DeVilbiss spray gun.  No filler, putty, or stain were used, the clear coat was applied right over the natural wood.  Click here and here to take a look at them, after final coat, but before we buffed out the finish.  Some people will like the contrasting wood colors, others won't.  We think it's beautiful.  One interesting aspect of this clear coat - no wax or polish is ever needed.  Wiping off the cabinets with a damp rag is about all the polishing or cleaning it requires.  And, like the Tung oil finish, touching up nicks is a breeze.  Unlike Tung oil, this stuff is expensive!  And once you mix the two parts, you either use it or throw it away.

Being an automotive finish, it is also water repellent. Should the Leslies get caught in a rainstorm, we'd likely have a few minutes to get them under safe cover.

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