From jackoverfull@gmail.com Sat Jun 28 08:19:03 2014
Subject:Re: Just What IS VASE III anyway?

Don't know if it will be "useful" to anyone but it surely was
"interesting" to me, thanks!

Sent from iPhone

Il giorno 28/giu/2014, alle ore 16.54, "jlcason@yahoo.com
[CloneWheel]" ha scritto:

> I can't find much information on the web today about the Hammond
> VASE system. When I moved from VA to NC in 2004, because of lack of
> room, I threw away about 90% of the service manuals accumulated over
> the years. However, I did keep some manuals. I've been out this
> morning in the shop checking them out, and found two that might be
> of interest, manual for the B-3000 (which was produced by Hammond of
> Chicago BEFORE the company was sold, and manual for the Super-B,
> which was one of the earlier Hammond Suzuki instruments.
>
> My language below is based on Section II, Theory of Operation, of
> the B-3000 manual (I'm not going to quote large sections due to
> copyright). NOTICE: This may be long and boring, but it does
> describe how the B-3000 operates, and it is information from the
> original manufacturer)
>
> Tone Generator: The process starts at the 440 Generator board, using
> a transistor Hartley oscillator at approximately 1.6 mHz. This
> signal goes to the Transposer board. When in tune position, a 1.88
> mHz signal is used for system clock to the Integrated Circuit
> divider that produces the top octave frequencies, from low B to high
> B. These 13 square wave signals are compared with the reference
> frequency and phase-locked loops keep them on pitch. They are fed
> to the 440 dividers.
>
> The "440" mentioned here is the generic designation of a particular
> Large Scale Integrated Circuit, which produces frequencies for all
> of the internal notes of the organ. Each 440 IC is responsible for
> three note division and keying. The Transposer Board also has the
> function of producing a 3,134 Hz signal that is used elsewhere for
> producing vibrato.
>
> There is a Timing Logic section of the B-3000, which maintains the
> time relationship between the keying, multiplexer, and de-
> multiplexer circuits. (this is similar to the keyboard scanning
> system generally used in all digital keyboards). Different time
> slots are used for Upper Manual tonebars, Upper manual percussion,
> Lower manual, and Pedals.
>
> Keying circuitry: There are 61 upper sustain and 61 percussion keyer
> circuits, 25 pedal keyer circuits, and 61 lower keyer circuits.
> These are located on three circuits boards (one of which is the 440
> generator board).
>
> Multiplexer section: This section has two main functions, first to
> provide buffered and multiplexed drive to the generator tonebar
> inputs, the other being to provide multiplexed bright wave signals
> for use in generating the lower manual bright wave tones. (these
> "bright waves" are used for generation of string tones present in
> the B-3000, but NOT present in the tonewheel B3). There are nine
> multiplexers on the board (one for each of the tonebar pitches).
> Separate circuitry exists for the generation of footage drive
> signals to the multiplexer. These must maintain correct DC
> amplitude and ADSR characteristics so the four basic subsystems can
> share the same 440 divider/keyer packages.
>
> Second or third harmonic percussion begins on the upper manual B
> preset.
>
> De-multiplexer area: The seven output lines of the 440 ICs are
> shared by the upper synthesis, upper percussion, lower manual,
> synthesis and pedals. The De-multiplexer circuits connect those
> signal output lines to the appropriate filter circuits (for tone
> shaping) at the appropriate times. (Again, this is typical of time-
> based multiplexing and de-multiplexing used in many different
> companies digital keyboards). The Upper and Lower manuals have
> Sine filters, converting the digital square wave outputs to sine
> waves (there are seven sections, each for different frequency
> ranges). There are separate filters for Percussion and for Pedal
> signals. There are also "lower bright filters" for the added string
> sounds.
>
> These sine wave signals go to the output board for mixing and pre-
> amplification. They then go to the Leslie Crossover Board (lower
> frequencies are separated and fed to the main channel to prevent
> distortion due to the inability of the Leslie rotary speakers (at
> least the ones used in the B-3000 and many of the Hammond home
> models of the time) to handle low frequencies.
>
> The organ also has a Reverberation Driver board, which drives a
> spring based reverberation network, and then is amplified to recover
> the loss of the network. There is also a Power Supply. The B-3000
> was designed to feed a multi-channel solid-state Leslie (with non-
> rotary, rotary, and low frequency amplifiers and speakers).
>
> The remainder of the manual has some test points and circuit
> pictures and diagrams of the seventeen printed wiring boards used in
> the instrument, then a parts list with part numbers.
>
> If I remember correctly, the most frequent problems in the B-3000
> were bad connections between some of the Molex plugs used to
> interconnect the various circuit boards. This was the FIRST
> GENERATION circuitry used by Hammond to produce an instrument that
> was sold specifically as a "clone" as it were, of the Hammond B3.
>
> Moving on to the H/S "Super-B" manual:
>
> The same basic digital circuitry of the Super-B was used in the
> CX-1, SX-1, CX-2000, SX2000, CX2500, and SX2500 models; although
> there were different features involving adding some boards on the
> different models. This manual has overall block diagrams, and
> schematics of each circuit board; but it does NOT have any
> description similar to the B3000 manual of how the circuits work.
> The information below is from my observations of the diagrams:
>
> The instrument has a digital section and analog (audio) section.
> The digital section is controlled by a Motorola 68000 CPU, 6809 MPU,
> and numerous LSICs. The tonebars go to an A/D converter, the
> keyboards and pedals go to a keyscan and switch scan circuit that
> functions with time-division multiplexing. There is an LCD display,
> and the instrument has both ROM memory and RAM memory (parameters
> can be stored - if any circuit boards are changed, an overall reset
> to factory parameters is needed). All of the various multiplexed
> digital signals are de-multiplexed and converted to analog. Once
> they are analog, they are mixed, reverb is added, and they go to
> separate pre-amps for Leslie and non-Leslie outputs. The instrument
> was designed to be used with a model 412L Leslie, which has Rotor,
> Left Stationary, Right Stationary, and Low frequency channels. The
> instrument has MIDI Input, Through, and Output.
>
> The MIDI and KeyScan Board is shown on four separate pages of
> schematics, and has both the main CPU and numerous special function
> LSICs. The Wave Generator Board has three sections, for pedal,
> manuals, and card voices (synth and piano). There is a Phase Pointer
> Board, Left Panel Switch Board, Right Panel Switch Board, Analog
> Interface Board, U.L. Switch Board (switches for "ProFoot 1 through
> 4, Transpose Up, and Transpose Down). Card Interface Board (this
> model had 40-pin IC Card connection for various cards which could be
> purchased to generate piano and various other sounds), Mixer Board,
> Key Switch boards for Pedals and each Manual - simple diode matrix
> switching is used like most other digital keyboards, Preset Key
> Switch Board, External Input Board (L&R Expression and non-
> Expression controlled), a Microphone Amplifier Board, Output Amp and
> Jack Board, and a Reset Board.
>
> I hope this information is useful to someone. Nowhere in either
> manual does it definitely state which version of VASE is involved.
> Another page found on the web for the XK-2 model states that it is
> VASE II, and that VASE actually stands for: "Versatile Advanced
> Sound Engine." The quoted text below gives some of the differences
> between earlier Hammond (VASE) and the XK-2 (VASE-II):
>
> The XK-2 digitally generates the pure harmonic sound of the classic
> B-3 including nuance characteristics of generator crosstalk and
> other important features such as adjustable Drawbar foldbacks at the
> top and bottom octaves, adjustable Attack (key click), and
> adjustable overdrive. Sixty-four user programmable presets,
> percussion 6 degrees of chorus and vibrato, and other B-3
> characteristics were designed into the XK-2 for maximum professional
> flexibility.
>
> Some early Hammond organ models lacked "foldback" found in the B-3
> and similar models. These models had keyboards which were wired
> differently internally with the first 12 bass tones normally found
> only on the pedals of B-3 and other organ models with foldback.
> Other later Hammond organ models had additional tones above the
> highest frequency tone found in a B-3. The XK-2 can easily be
> configured to recreate these earlier or later organs to suit the
> organist's playing needs by altering the adjustable foldback points."
>
>