What separates organ sound from everything else in the musical universe is it's unparalleled range, substantial tonal spread, sheer thrilling power, and bass below the limits of audibility sensed as purely physical subsonic energy.  So when we start thinking about adding subwoofers to our home practice instrument to help bring out this pervading bass there are some points to ponder.  Three parameters are brought into play:  1) small enclosure [cabinet] size, 2) deep [low] bass production, and 3) high [output] sensitivity.  With subs is seems we can't have our cake and eat it too; picking any 2 of these parameters will compromise the third parameter.  This principle is known as Hoffman's Iron Law.  If given a choice the average stereo home owner would opt for all 3 parameters -- a high output sensitivity speaker in a small cabinet that plays extremely deep -- but that desire runs smack up against this law of physics.  In the end, speaker selection is all about trade-offs.  If we're willing to sacrifice some bass extension and live with a relatively large speaker cabinet, then high sensitivity cone drivers are still available, but spouses usually don't like large cabinets [they're more costly anyway], and most consumers prefer reasonable bass extension.  This means that, when we want low bass reach and high output sensitivity in a sub, we have to go with a larger cabinet.  If we want high output sensitivity and a smaller cabinet, there goes our low bass reach.  In the case of organ sound very low bass reach is a must, so, when it's necessary to go with a smaller cabinet, the output sensitivity will be compromised.  We can get around that to some extent by finding a good, high-power amp to drive it.  This explains why we find subs enclosed in smaller cabinets that bottom out in the 20Hz range being driven by amps pushing a lot of watts.  A sub speaker cone with higher output sensitivity wouldn't need such a big amp to drive it.  Today most speaker manufacturers want to offer extended bass response, so they put most of their R & D [research/development] efforts into low output sensitivity drivers that can play very low bass in a small cabinet.  While perhaps these lower sensitivity ratings are less than many people would like, the wide availability of high-power amps make the trade-off a reasonable one.

Unless we're in a purpose-built listening room the frequencies at which subwoofers play are also subject to room nodes.  Very few owners have an ideal listening room in their residence let alone one large enough not to be affected through the bass/deep bass bandwidths.  They're not interested in power so much as extended, low bass reach.  This application, with the console placed in a living room 12 x 14 feet connecting with a kitchen of the same size, is a case in point.  Placement is therefore of prime importance when just one subwoofer is used.  While the music plays, as we move around the room, we can notice areas of drastically increased bass and other suckouts where the sub seems to be off.  When this occurs the preferable way to get around it, for a number of reasons, is to use multiple subs with deep bass reach housed in smaller cabinets, variable crossovers set at their minimums, and running at half to 2/3 volume [4 subs is usually enough to knock out these problems in 99% of the rooms likely to be encountered].  Clean, tight bass quality is not so proportional to woofer size as many might suppose -- some 18" woofers reach no lower than 35Hz while others no bigger than 10" reach down to 18Hz.  But as volume goes up, a smaller woofer, generally speaking, will start to lose its composure where a larger woofer wouldn't need to work so hard to attain the same volumes.  Much like car engines, there's no replacement for displacement, and small diameter subs will not perform as well at high volume levels.

The crossover [cut-off] frequency of a subwoofer is the frequency at which the sub kicks in with bass.  Unless one spends thousands of dollars on a super-sized mega-subwoofer powered by an amp of sufficient size to run a radio station single-handedly most home theatre-style subwoofers generally available all tend to roll off quickly upon entering the 32-foot octave [30Hz and below].  This can be counteracted to some extent by using equalizers which boost frequencies in the 20Hz range and using multiple long throw subs.  When the frequency range of the other bass woofers in the room is known, the sub's crossover, when adjustable, should be set roughly 10Hz above the lowest frequency the other speakers can handle cleanly.  Some careful listening and experimentation is needed until the ear finds a smooth transition between the other speakers and sub so that, ideally, the slight overlap and blending is so seamless that the bass cannot be localized and everything will play in unison.  When several subs are in use, unless some special purpose is being aimed at it also helps to stagger their crossovers so that duplications are minimized.  Some general guidelines for setting crossovers on subs when they play with other speakers of different types can be recommended:  1) for on-wall or very small, compact satellite type speakers 150Hz-200Hz, 2) for small center, surround, or bookshelf type, 100Hz-120Hz, 3) for mid-size center or surround, 80Hz-100Hz, 4) for large center or surround, 60Hz-80Hz, 5) for very large center or surround, 40Hz-60Hz, 6) for floor-standing towers with 4"-6" woofers, 60Hz, and 7) for floor-standing towers with 8"-10" woofers, 40Hz.

All sampled voices in this instrument are sourced, separated, and stored by division on computers inside the console, one for each manual and Pedal.  A single master computer controls these 6 "slave" computers.  Voices, couplers, and tremulants are brought on or retired by means of lighted drawknobs and lighted manual and toe pistons.  Lighted rocker tablets paired with an 8-position factory-set Crescendo indicator are built into the rail above the top manual controlled MIDI, Voicing Variations, and divisional Reeds Cancels.  All drawknobs and rocker tablets remain in alignment in both on/off positions.  Standard TRS (1/4" phone) jacks in the back of the console allow for up to 3 separate mono outputs per division along with a pair of special combined mono outputs for Great/Choir-Positiv/Pedal and Swell/Solo/Echo, all for connection of external powered speaker cabinets.

The power requirement to run the console is 520W.  Its self-contained speaker system consists of a lone pair of 12" woofers each powered by its own 80W amp having a combined audio output power of 160W.  The console is supplied with adjustable factory reverb, 2 tremolo speed controls [Swell/Echo + Great/Choir-Positiv/Solo], and 2 tremolo depth controls [Swell + Choir-Positiv].  Whenver the entire signal stream is run through a single woofer the mammoth excursions it makes with lower frequencies interfere with its ability to create the finer movements needed for midrange and higher frequencies.  This is called "intermodulation distortion" and robs the midrange and treble of some of its clarity.  The solution is to employ a crossover network that divides the signal stream into specific bandwidths which can be sent to multiple woofers, tweeters, and subwoofers engineered to best reproduce those frequencies.  In this application the sound is sourced and separated this way using a non-factory mix of new and pre-owned equipment.  Three separate external speaker systems [MAIN/MONITOR, SMALL AUXILIARY, & LARGE AUXILIARY] each make their own individual contributions to the sound.

CAUTION:  Instead of plugging everything electric into unprotected wall receptacles, we always connect the power cords for the console and any other external amplifiers to a power strip (surge bar) that has either a built-in circuit breaker or red protection light, and keep the power strip turned on, 24 hours a day.  When the red light is on, this means its surge protection is working; if the red light won't turn on, the power strip should be replaced.  This helps protect the console's internal motherboard and its fuses from power surges, including lightning storms [if the console isn't working after a big storm, the console's fallboard should be closed, the back of the console removed, and fuses should be checked and replaced if needed].  If any add-on voice modules lack an on/off switch, then their power line needs to be disconnected and reconnected each time they're used, leaving the power strip on all the time.  To avoid possible fire or electrical shock when using an extension cord plugged into a power strip, we never daisy chain in series multiple devices to that same extension cord [See blog, Conn Speaker Pipes, for more about wiring].    

NOTE:  When this organ is used with external speaker systems and equalizers it becomes incumbent to run scales up and down the keys starting with 16-foot manual voices, then moving on to 8-, 4-, and 2-foot voices, to determine if any bandwidths sound louder than others and, if so, to give them a negative boost in order to regulate them so that all frequencies are of roughly uniform strength.  When multiple Conn speaker pipe units are engaged they enrich and brighten the sound, thus manual upperwork [4-foot stops and higher] needs to be drawn very sparingly to keep from swamping the pipes (the Echo 4-foot Flute, 2-foot Flute, and soft mixture coupled to the Choir/Positiv 4-foot Principal might be all the upperwork needed to crown the full organ).  This organ's stop list is already top-heavy with upperwork, almost all of which tends to fight with the speaker pipes when drawn.  Thus a good deal of judgment and experimentation is needed to arrive at a sound that's balanced, keeps everything in happy agreement, and can be listened to for long periods of time. 

1.  The MAIN/MONITOR speaker system has 2 channels which receive individual mono output signals from all 6 divisions of the instrument through jacks in the back of the console.  These connect with a Peavey XR8300 power mixer supplied with dual 300W amps controlling MAIN and MONITOR channels, each of which is supplied with its own built-in 7 band dual graphic equalizer (EQ) which on both MAIN and MONITOR channels is set for negative boost of -12dB @ 80Hz, -3dB @ 250Hz, -6dB @ 500Hz, and -12dB @ 1kHz, 2kHz, 4kHz, and 10kHz.  The output signal from both channels of this power mixer then loops through a DOD 231 series 31-band dual graphic EQ which retains a flat signal for all bandwidths save for boosts of +12dB @ 20Hz & 25Hz, +3dB @ 31.5Hz, and negative boosts of -3dB @ 50Hz, 160Hz, 200Hz, & 250Hz, -6dB @ 63Hz, 100Hz, 125Hz, 315Hz, 400Hz, & 500Hz, and -12dB @ 630Hz & all higher bandwidths through 20kHz.  After looping the signal through these EQ settings the mixer adds its own onboard Peavey reverb.  The MAIN output signal then routs to a Velodyne Servo F-1800RII powered subwoofer supplied with an 18" driver, internal amp rated at 600W, and low crossover set at minimum [40Hz].  This sub is front-firing and has a listed frequency response all the way down to 16Hz [32-foot C].  This sub routs all remaining signal to a free-standing BSR passive subwoofer cabinet retrofitted with a Memphis 15" floor-firing subwoofer which works in partnership with the Velodyne to capture all remaining bass, upper bass, and low midrange frequencies up to 120Hz.  The outgoing signal from this Memphis sub is then routed to a pair of BSR Colossus R/L passive stereo cabinets each rated at 200W.  These retain their own original pair of BSR 2" ceramic tweeters but are retrofitted with new Memphis (15") and Pyle (8", 5") drivers.  A built-in crossover network in each BSR cabinet divides the incoming audio stream into 4 different frequency bands and sends them to drivers of appropriate size [120-800Hz to the 15", 800-1200Hz to the 8", 1200-3400Hz to the 5", and above 3400Hz to both tweeters].  Positioned to the right of the console this system disperses the sound to the right, left, and rear of the room.

CAUTION:  It's advisable to first set volume controls for subwoofers at half position or less when testing, and perhaps no higher than 2/3 after that, this to avoid compromising the speaker cone in the event of any sudden, extremely strong bass pulses in the signal stream.

      The MONITOR output signal from the Peavey power mixer is routed separately to a Peavey PV215 passive 3-way trapezoidal enclosure PA cabinet equipped with a pair of 15" heavy duty woofers and a 1.4-inch RX14 titanium tweeter driver mounted on a 60 X 40 degree coverage constant-directivity horn.  This cabinet is rated at 700W through 4 Ohms, has a crossover frequency of 2.6kHz, a frequency response of 58Hz-17kHz, and a frequency range of 40Hz to 21kHz.  Positioned to the far right of the player it speaks in that direction.  A spare monitor out jack at the Peavey mixer also routs the signal behind the console to a Sony SA-3000 powered subwoofer equipped with a 12" long throw driver and 180W amp having a listed frequency range down to 20Hz [32-foot E] and crossover set at minimum [60Hz].  This MONITOR channel can be made to play all by itself by not turning on the Velodyne sub, but when the MAIN channel plays it always joins with the MONITOR to provide a more realistic and expansive sound.  These channels have a combined audio power of 600W (Peavey) + 600W (Velodyne) + 180W (Sony) = 1380W, and all of the console's factory voices play through them.

An Allen MDS-Expander II external module is also MIDI-connected to speak through this MAIN/MONITOR speaker system but operates only on the bottom 3 manuals and Pedal.  Its voices thus are equalized and mixed with reverb at the Peavey mixer.  This Allen module is a stand-alone add-on unit which can be MIDI-assigned to play on any organ's two or three bottom manuals and pedals.  Its supplemental voices include classic organ stops, mutations, and ancient reeds, theatre organ ranks, percussions, and orchestral and other keyboard instruments.  As many as 4 voices out of the 99 program numbers onboard may be accessed simultaneously.  In this organ selected Allen voices are assigned to individual Viscount MIDI rocker tabs situated in the rail above the top manual controlling Swell, Great, Choir/Positiv, and Pedal divisions which then can be captured and stored on general or divisional pistons.  The four selected voices programmed on Allen Channel 1 which play from this organ's Memory One [German Baroque] are:  Sw 8' Rankett, Gt 8' Barpfeife, Ch/Pos 4' Rohrschalmei, Ped 16' Dulzian.  The four selected voices programmed on Allen Channel 2 which play from this organ's Memory Two [French Romantic] are:  Sw 4' Viole, Gt 16' Bassoon, Ch/Pos 16' Trumpet, Ped 10-2/3' Flute].  Much experimentation using the ear was involved in selecting these specific voices for what they supply to complement the factory voices in the divisions, fill in missing overtones, and play a role through coupling in the buildup to full organ.  Among its many features this module's voices and flexible tuning has been of significant use in providing greater tonal spread, realism, and something of the same sound world known to composers.  It increases the number of speaking stops in this organ to 92, raises the number of available equivalent ranks to 123, adds fire and life to the fuller ensembles, and makes playing the instrument now a complete adrenalin rush [the module in this application is adjusted to play very slightly out of tune with the main console -- sharp by just one Cent (1/100th of a chromatic semitone) to more closely approach the random tuning characteristics of real organ pipes].      

2.  The SMALL AUXILIARY speaker system is also supplied with 2 channels, the first of which makes use of an output jack at the console for just the Pedal division.  This connects with a Roland KCW-1 powered keyboard sub placed behind the player having a 200W amp and supplied with a single 10" bass reflex woofer.  The frequency response of this unit is not listed by the manufacturer, but its low reach is likely in the mid-20Hz range due to its [30Hz] minimum cutoff.  With its cutoff set there and its bottom switch "on," a line out from this sub routs the low bass-stripped signal to a smaller Sony SA-WMS325 powered subwoofer rated at 75W equipped with a single 6-3/8" cone-type, front-firing woofer, and built-in frequency range of 28Hz-200Hz.  This unit is also situated behind the player, captures all remaining bass and low midrange frequencies below 200Hz, and sends the remaining signal to a pair of Conn speaker pipe cabinets [models 145-2 and 146-1, both silver finish] each equipped with 4 upward-firing 6 x 9" oval Cletron speakers wired in series parallel and mounted end-to-end.  A Thru-Out jack from the Roland sends the unchanged Pedal signal via a splitter cable to 2 additional powered subs -- a Polk Audio PSW505 supplied with a 300W amp and 12" long throw woofer, and a Sony SA-WM250 supplied with a 100W amp and 8" long throw woofer.  The listed frequency response for the Polk is down to 23Hz [32-foot F#] and for the Sony is down to 20Hz [32-foot E].  Both subs are set for minimum cutoff, [60Hz] for the Polk and [50Hz] for the Sony.  Still another Thru-Out jack at the Roland sends the unchanged Pedal signal via a splitter cable to another pair of powered subs -- a Bic America PL-200II equipped with a 250W (1000W peak) amp and 12" long throw woofer, and a Definitive Technology ProSub1000 equipped with a 300W (750W peak) amp and 10" long throw woofer pressure-coupled to a 10" low bass radiator, an arrangement that provides 39% more cone area than a 12" woofer.  The listed frequency response for the Bic is 21Hz that's been tested virtually flat down to 20Hz [32-foot E], and for the DefTech 18Hz [32-foot D].  Both of these subs are also set for minimum cutoff, [30Hz] for the Bic and [40Hz] for the DefTech.  This channel specially functions to supplement Pedal voices with very low bass strength and speaker pipe effects.

The second channel is supplied with special reverb and makes use of 2 special jacks at the console which send line output signals for Pedal/Choir-Positiv/Solo and Great/Swell/Echo to an Alesis Nanoverb 18-Bit Digital Effects Processor having a frequency response down to 20Hz [32-foot E].  Here the signal is mixed with "Nanoverb Hall 3" Alesis reverb then looped through a duplicate DOD 231 series 31 band dual graphic EQ with input gain and sliders settings controlling frequency bands set exactly the same way as its counterpart in the MAIN/MONITOR system.  This reverb enriched, equalized signal is then relayed to a 2 x 50W Sunbuck AS-22 mini-amp with its bass control set at max and treble set flat.  The bare wire outputs of this mini-amp rout the signal stream to yet another Peavey PV215 passive 3-way trapezoidal enclosure PA cabinet identical with the one used with the MONITOR channel and a Sony SS-U4033 passive 3-way floor-standing cabinet equipped with an 8" woofer, 3" midrange, 1" tweeter, and rated at 100W, 140W peak.  Positioned behind to the right and left of the player, respectively, these cabinets face and disperse sound to the left and rear of the room and function to supply spatial reverb, ambience, and additional power to complement and perfectly partner with the MAIN/MONITOR system.

The combined audio power of both channels of this SMALL AUXILIARY speaker system computes to 275W (Roland/Sony) + 400W (Polk/Sony) + 550W (Bic/DefTech) + 100W (Sunbuck) = 1325W, and the entire organ plays through it.

   3.  The LARGE AUXILIARY speaker system draws more power than the other 2 speaker systems combined, operates only on manual voices, and is supplied with 3 separate channels, the first two of which work together.  A 2400W Rockville RPM80BT 8-channel power mixer receives signal from each of the console's 5 manual out jacks and combines them into a single mono signal.  Its built-in 5-band EQ is set flat @ 250Hz and at -12dB negative boost @ 60Hz, 800Hz, 2kHz, and 8kHz.  With individual channel controls set flat for bass and minimum for treble this single output signal is then mixed with built-in Rockville reverb and routed to a Klipsch KSW200 powered subwoofer equipped with a floor-firing 12" bass reflex driver, 200W amp, and listed frequency response down to 31Hz [16-foot C].  With its crossover set at its highest [120Hz] the "speaker-out" bare wire terminals from this sub rout the remaining low-end-filtered Rockville signal to another pair of Conn speaker pipes [Models 145-3, 146-2, both silver finish].  Each set is rated for a load of 8 Ohms, equipped with four Cletron 6" X 9" oval speakers wired in series parallel, and designed to operate only at treble and high midrange frequencies with a practical downward limit of 200Hz corresponding to the 8-foot tenor G# note [208Hz].  This channel also disperses the sound to both sides of the room.  A second 8 Ohm line output jack from the Rockville directly routs signal to a Sony SA-WM200 powered subwoofer equipped with an 100W amp and 8" long-throw driver.  Its listed frequency response down to 28Hz [32-foot A] covers all manual suboctave voices, and with its crossover set at maximum [200Hz] all manual notes from about 8-foot tenor G# on down are strengthened.  This sub is side-firing, situated to the right of the console, and disperses sound in that direction.  This Sony sub's "speaker-out" bare wire terminals send the remaining bass-filtered Rockville signal to yet another pair of Conn speaker pipes [Models 145-1, 146-2, both gold finish] situated directly behind the player.

NOTE:  Conn speaker pipes were one of a number of attempts made by various builders of the time to improve the sound of early analog organs.  As stated, these are strictly treble and upper midrange units made up of narrow scale, cylindrical, anodized aluminum pipes of different diameters and lengths tuned to sympathetically resonate with the notes of the chromatic scale.  The Conn theory was that individual frequencies generated by the upward firing speakers would find their own pipes and make them resonate.  These units impart to manual stops a distinctly audible brightness, a finespun but discernable edge to individual voices, dispersion of sound vertically upward throughout the room, and a very subtle but measurable buildup and decay of sound when keys are pressed and released, respectively -- pneumatic effects which can be heard but not counted.  Used all by themselves the results can be disappointing when compared with the efficiency of speaker drivers mounted in conventional cabinets -- that is not what the Conn pipes were meant to do.  When they are used the sound takes on a bright quality lacking any trace of annoying, piercing shrillness and becomes omni-directional like a subwoofer, adding a touch of ambience and depth as the sound seems to come from every corner of the room.  These units provide all the upper brilliance needed for the full organ, thus the treble frequencies reaching any other speakers used with them needs to be deliberately suppressed.  CAUTION:  THESE UNITS NEED TO BE SHIELDED FROM ALL BASS AND LOW MIDRANGE FREQUENCIES.  This seems to be most easily accomplished by filtering their incoming signal stream through a powered subwoofer having a high built-in crossover [or by setting its crossover control at maximum].  The result is the enhancement of all manual voices sounding at pitches above the 8-foot tenor G note frequency [195Hz] with the addition of the aforementioned brightening and pneumatic effects which, again, are noticeably audible and cannot be duplicated by merely turning up the treble controls of amplifiers.

A third 8 Ohm line output jack from the Rockville is connected to a JBL Sub150 powered subwoofer equipped with a 300W amp, 10" bass reflex driver, and listed frequency response down to 27Hz [32-foot A#].  Positioned to the left of the player its crossover is set at max [150Hz] which adds strength to the bass octave of all manual unison and suboctave stops.

The second channel of the LARGE AUXILIARY speaker system is completely pipeless and begins with a single line out jack at the Klipsch subwoofer.  This line out sends its low-end-filtered Rockville signal to a 250W Radio Shack MPA-250B amp.  This amp then routs the signal via bare wire out terminals to a pair of Sony SS-F5000P passive floor-standing speaker cabinets each rated at 180W and equipped with a crossover network, 6-1/2" Kevlar woofer, 3-1/4" Kevlar midrange cone, and 1" high dome tweeter.  These cabinets are positioned behind the console and disperse sound in that direction.  Another set of bare wire outputs from this amp routs the signal to an additional pair of Acoustic Audio BR-10 passive 3-way Karaoke speaker cabinets each equipped with their own crossover networks and a 10" lower midrange driver, 4" upper midrange cone, and 10" X 4" horn tweeter.  Positioned on top of the console these cabinets disperse the sound directly at the player. 

The third channel of the LARGE AUXILIARY speaker system employs a separate 60W Choice Select ST2060 amp which can receive signal from as many as 3 mono output jacks at the console [Swell, Solo, and Echo were selected].  With its bass control set flat and treble near minimum the mixed signal from this amp is then routed via bare wire out terminals to a pre-owned specially custom-built PVC pipe speaker box created in Lodi, California by the McCurdy Corporation.  This unit is made to work with larger pipes and is of singular construction.  It consists of 12 general purpose 3-1/2" diameter PVC [polyvinyl chloride] cylindrical pipes all of the same diameter [3-1/2"] bundled together and positioned vertically on end over a wire baffle situated above a round opening in the top of a square, hollow wooden box, inside of which is mounted a single upward-firing Radio Shack passive 12" woofer wired to play all frequencies arriving from the amp.  This unit is positioned behind the console and disperses sound in that direction.  The pipes are painted in a metallic gold leaf color, cut to various lengths determined by their locations over the speaker cone, and engineered to sympathetically resonate with fundamental low midrange and upper bass frequencies generated by the 12 chromatic semitones from 200Hz [8-foot tenor A] down one octave to 100Hz [8-foot bass A].  The longest pipe of this unit when in operation was found to resonate very strongly as a 2nd harmonic on the tenor Bb note.  It's practical upward range therefore extends one more semitone higher than tenor A to about 226Hz, overlapping slightly the lower limit of the Conn model 146 speaker pipes and thus extending their effects an octave lower without noticeable break.

The maximum combined audio power of all 3 channels of this LARGE AUXILIARY speaker system calculates to 2900W (Rockville/Klipsch/JBL) + 250W (Radio Shack) + 60W (Choice Select) = 3210W, and it functions to enrich and strengthen all manual voices.

The sound of this instrument has been substantially improved by these 7 external speaker system channels, 3 additional reverb systems, 13 subwoofers, and 54 additional woofers and tweeters.  These speakers range across 16 sizes from 18" down to 1", and their amplifiers when fully engaged push 5915W.  The entire speaker array breaks down as follows:  one 18" powered SUB, one 15" passive SUB, six more 15", three 12" long throw powered SUBS, one more 12" powered SUB, two [internal] 12", one more 12", three 10" powered SUBS one being long throw pressure coupled to a separate 10" low bass radiator, two more 10", two 10" X 4" horns, two 8" long throw powered SUBS, three more 8", twenty-four 6" X 9" ovals, one 6-3/8" powered SUB, two 6-1/2", two 5", two 4", two 3-1/4", one 3", four 2", two 1-1/2", and two 1".

The goal of this project was the creation of improved ambience, realism, and power from an older digitally sampled instrument, striving for an unforced but enhanced dispersion of sound throughout the room as a cost-effective, next-best alternative to a total rebuilding with touch screens and sample sets.  By hunting down new and repurposed electronics and cobbling various units together in carefully calculated ways, and with painstaking and patient experimentation using the ear to adjust volumes, balance, treble/bass, equalization, and artificial reverb, the combinational tone with all systems running, for a home practice instrument, has proven more than sufficient to satisfy the serious organist.  The improvements to the sound these various extensions, retrofits, add-ons, and adjustments have made have been surprising and really quite extraordinary.  The audio power of the instrument has been multiplied more than 10 times, the full organ is majestic, individual stops speak with more realism, and the speaker pipes add a singular brightness and pneumatic resonance.  Perhaps most importantly, the fullest ensembles are much more realistic and, as with a real pipe organ, can be listened to for long periods of time.   

Most manufacturers of sampled organs, for marketing purposes, say they record (or sample) every note of every stop (not necessarily every rank).  They may even say that their original samples are 30 seconds long or even 60 seconds long.  They may even boast about what bit-rate, sampling rate, etc., they use.  In actual fact it is very hard to get all notes of a rank in a pipe organ to sample perfectly.  Most ranks have notes which are "off" either in volume or tone.  What they actually put into their instruments therefore is going to be something that is vastly reduced, so, just a basic sampling system doesn't really make a digi organ sound exactly like a pipe organ.  The behavior of a wind instrument also needs to be reproduced.  Therefore things like wind noise ("chiff") as pipes get on speech have been put into digi organs like this one but still they end up sounding a little too focused and straight.  The biggest problem manufacturers face is, what can be done at what price.  Companies experience periodic lulls in sales, there has always been serious price competition, and, in order to stay price-competitive, most sampled organs are seriously compromised.  The marketplace for digi organs is such that, most purchasers want more stops, more manuals, etc., rather than the very highest quality musical result.  This has everything to do with the way manufacturers must design their line of products.

With its Echo (5th) manual and rack so far away, intramanual couplers absent, and the crescendo shoe non-programmable, there are certain challenges to playing this organ, but its sound stands or falls on whatever external speaker system(s) are provided, how its divisions are tuned, and how its voices are mixed and coupled between divisions.  If divisions are all tuned exactly true to the Great and each other the sound is dead and lifeless, but if too far sharp or flat from the Great the beating is objectionable.  The trick is to find that sweet spot which has each division tuned just barely different from the Great but not enough to produce noticeable undulations.  The entire organ's pitch is adjustable up or down from A440 by means of a general pitch control knob.  The other 5 divisions are made tuneable up or down to the Great by means of their own individual pitch control knobs, all of which are situated out of sight under the bottom manual within reach of the organist's left hand.  Since the ear will tolerate a little sharpness but not the same degree of flatness, it was decided, using the ear to adjust the amount, to tune the Echo very slightly sharp and the Solo very slightly flat so that, when the hands go to the Solo and the Echo is blended in, the random tuning effect of a pipe organ is suggested.  Similarly the Swell was tuned a little bit more sharp than the Echo, the Choir a little bit more flat than the Solo, and the Pedal just barely sharp to the Great.  This was accomplished by drawing the loudest 8-foot reed in each division, coupling them one at a time to the Great Trumpet, listening for beats, and adjusting divisional tuning knobs accordingly.

The mistuned ranks (celestes) inserted by the builder in a pipe organ typically are never drawn in fuller ensembles, but in an organ like this some of these celeste stops, as long as they're not too assertive and don't create a disturbing pitch "warble," may be drawn with advantage in fuller ensembles to simulate the random effect of minute pitch variations among real pipe ranks.  Some serious trial-and-error experimentation is needed, of course, it's a bit tricky, but the ear is still the best judge as to how much of this may or may not be good.  In this organ all 8-foot celeste stops automatically draw the "mate" rank tuned true which is given its own drawknob, and, with manual division tremolos in this organ being adjustable for depth and speed, compound tones of great beauty are possible by coupling voices -- some mistuned (celestes), some tremmed, and some untremmed -- located in different divisions.

This instrument came with 2 percussion stops (Great Chimes & Solo Harp).  The top octave of the Great Chimes (C#50 to C61) was wired to double back an octave, but, unlike the Chimes in many pipe organs, it did go all the way down to bottom C1 and thus represented 49 equivalent bars.  The Solo Harp ran all the way up to top C6 without doubling back and thus comprised 61 equivalent bars.  Every stop in this organ including Chimes and Harp was equipped with 2 voicing variations (A and B) controlled by tilting tablets which permitted the organist to select from 168 equivalent ranks.  The A voicing reflected more traditional voicing whereas on B the change in harmonic content in the strings and reeds resulted in a different tone, brighter in many cases, the open flutes changed to stopped, and the Principals and Diapasons became either brighter or more bland and flutey-sounding.

As for the tonality of individual stops, the Great Principal is extremely big like an English 1st Open Diapason.  When a leaner chorus is desired the Salicional may be substituted which is more like a 3rd Open in tone and strength; on B it's voice is less assertive, keener, with a prominent 12th.  The 16-foot Principal is also big and on B inclines to a dull tone with less harmonic content.  The Flute Celeste is paired with the Bourdon and is extremely strong but good if the Great volume is turned down all the way.  The 4' Rohr Flute is good for solos, a big, burbley flute full of color in its lower range.  The Great Trumpets, as expected, are loud and bright.  The Swell Principal is a 4th Open in strength and in combination with the Viole is very French sounding.  The Swell flutes are all good and, as expected, are available at 6 pitches.  The Swell reed chorus stands on a big Contra Fagotto and two Trompettes of medium strength at 8' and 4' pitches, respectively.  The Principal in the Choir/Positiv is a 2nd Open in strength.  The Hohl Flute is open on A, stopped and hollow-sounding on B with less harmonic content, but good for solos on A or B, with or without Tremolo.  The Cromorne on A is very French-sounding, on B more like a Clarinet.  The Solo Diapason is big, of large scale, neutral in tonality, and finds its best use as a helper stop, adding desirable power to the Tuba Mirabilis without appreciably affecting its tone.  The Gamba and its paired Celeste are good and, curiously, are both identical on A and B.  The Gemshorn is bright but not overbearing, and the Octavin is very bright and assertive.  The Bassoon on A is very realistic for an actual Bassoon; on B it's brighter in the midrange and rounder in the bass.  The Orchestral Oboe, as expected, is thin and keen, an excellent solo stop, and also comes in handy when coupled for adding definition to a chorus without dominating.  The Cor Anglais is very big and rather dull in tone.  The Echo Cor De Nuit on B is very French sounding.  The Erzahler is most beautiful on A, thinner and brighter on B.  The Bombarde chorus is a bit raspy in tone, full of harmonic content but tame in strength.  This Vox Humana in this division is especially  good -- a "Vox to die for" -- on A it's mixed with a soft helper stop, and on B it's by itself.  The Pedal Principal is like a big English Open Wood, and on B it's dull and flutey in tone.  If a lean full organ is desired it may be left out along with the Great Principals and the less assertive Violone substituted.  The Pedal Fagott is extremely strong and dominates when introduced.  The 4' Schalmei is very nasal, good by itself in Pedal solos with the Clarion preferably drawn in the full organ.  Curiously, the Contra Bourdon is not a flute voice; instead it's tone, being an exact match to the Violone, is best used that way, i.e. as a "Contra Violone."  When supplied with sufficient external amplification, equalization, and subwoofer speakers this stop, along with the Contra Bombarde, is very realistic and valuable in adding depth and gravity to all fuller ensembles.

Each voice in this organ is independent with no unification or duplexing, and the Pedal Fourniture V is the only mixture stop in the organ without breaks.  All others have one or more breaks, and the Swell Plein Jeu III sounds only through the bottom half of the Swell manual -- at F#43 it drops back, thus, above that note it sounds more assertive than expected.  All (6) 16-foot manual stops run clear down to the bottom without breaking back.  Voices of 2-foot pitch or higher either break back in the top octave or end at the top with a few "dead notes." 

GREAT

2' Super Octave G56 -- C61, 6 dead notes at the top

SWELL

2' Flautino G56 -- C61, 6 dead notes at the top

1-1/3' Larigot doubles back from C#50 -- B60 over 11 notes (C49 and C61 are dead notes)

III Plein Jeu doubles back from F#43 over 19 notes

CHOIR/POSITIV

2' Doublette G56 -- C61, 6 dead notes at the top

1-3/5' Tierce D52 -- C61, 11 dead notes at the top

1' Sifflote G44 -- C49, G56 -- C61, 12 dead notes at the top

SOLO

2' Octavin G56 -- C61, 6 dead notes at the top

ECHO

2' Flautino G56 -- C61, 6 dead notes at the top

This represents a total of 111 equivalent small pipes in the manual divisions which do not sound.  When this is factored in, we find an instrument capable of commanding the equivalent of 5,779 sounding pipes on the A voicing variation, and the same number on B.  This means that it would take a pipe organ of 11,558 separate individually voiced pipes to make available the same tonal spread and range of pitches.  The Allen module on Memories One and Two adds the equivalent of another 430 sounding pipes, representing the equivalent of an instrument commanding nearly 12K [11,988] pipes. 

Phone (1/4") output jacks, three per division. provided at the back of the console allow it to send as many as 18 separate output signals to external amps and speaker cabinets.  The console is Guild standard, supplied with Fatar premium keybords, MIDI friendly, and equipped with lighted MIDI rocker tablets for MIDI program changes by division which make it capable of storing sounds from an external sound module on its piston memory.  It may also be retrofit with Hauptwerk sample sets, should that be desired.  Separate divisional cancels which operate by pressing the various divisional labels situated at the top of the stop jambs are also provided.  The combination action is computer capture with 8 programmable memory banks.  Additional controls provided include Ventil tilting tablets which silence reeds or mixtures (duplicated with toe studs), a Pedal to Great (Automatic Pedal) reversible piston, a reversible Tutti piston and toe stud, "O pistons" which remember starting hand registrations, all the usual intermanual and manual to pedal couplers, a registered Crescendo shoe with 8 lighted positions, separate expression shoes for the Swell, Choir/Positiv, Solo, and Echo divisions, an All Swells to Swell piston which makes the Great and Pedal expressable through the Swell shoe along with all the other divisions, divisional Tremolos adjustable for depth and speed, adjustable Great, Pedal, and Master Volume, adjustable Brilliance control, transposer, pitch control, divisional generator tuning, and headphone jack.

The biggest challenge with performing solo repertoire on this instrument is settling upon a scheme for drawing and coupling the voices to approach something of the sound world the composer knew.  It works well for the player when the premise is that the Solo is part of the Swell; this makes for a massive voice palette for coloration of sounds and a massive dynamic palette with compound flexibility and expression for nuancing the music.  If the player's hands happen to go to the Solo, it works well to have the Echo blended in. The same can be said for coupling the Swell to both the Great and Choir/Positiv and coupling the Choir/Positiv to the Great.

This organ of 84 stops, for its size, is overly supplied with assertive upperwork (octave stops and higher) and undersupplied with manual Doubles (there are only 6 in the whole instrument, however all of them go all the way down to bottom C without doubling back).  Being somewhat deficient in manual suboctave tone means that when drawing the full organ pretty much all manual Doubles need to enter and the percentage of upperwork demand reduction.  The Great sub coupler, in particular, an essential element of the sound universe known to 19th and early 20th century French organists, especially Franck, Widor, and Vierne, a coupler which had much to do with the way they notated their compositions, is entirely lacking.  Without it, big final spread chords above middle C sound thin and less sonorous when performed exactly as written -- in which case it might benefit to experiment at changing the manuscript mentally by adding a note to the bottom of the final left hand chord or with the right foot high in the pedal to help provide the missing gravity.  As stated, in an organ like this with divisional tuning, voices from different divisions including even a celeste or two may need to be drawn and coupled in combination to get something of the same random chorus effect of a pipe organ.  Individually some of the voices are quite beautiful and very useful on A Voicing, on B Voicing, or both.  Then again, some of them are so dull or shrill in tone that they have little use on A or B, dated technology being largely responsible.  Curiously, the Pedal division of 16 stops, relatively few for an instrument of this size, is supplied with 6 stops of superoctave (4-foot) pitch or higher but only 5 stops of that all-important unison (16-foot) pitch.