Information and Discussion on Original and Brand New Series 122 and 147 Leslie's
The Leslie 'Sound-in-Motion'
The Hammond organ is synonymous with classic Rock, Blues, Jazz , Gospel, Country and other music styles. But, it's famous partner, the Leslie speaker, is an equally important part of the classic Hammond sound. Most console Hammond organs without speakers were originally outfitted from the factory with Hammond Tone Cabinets containing traditional speakers. The motorized, rotating horn design, Leslie Speaker quickly became the famous partner of the Hammond organ. Don Leslie's early dream of a true 'rotary' speaker system for his Hammond organ soon became the professional standard for Hammond organists worldwide. From the first tube amplifier powered single-speed Vibratone Leslie models through many tube and solid-state amplifier powered two-speed Leslie models made for Hammond's and virtually every other brand of organ, this classic 'Sound-in-Motion' is still the musical standard, as evidenced by the introduction of other rotary sound units, and most recently, digital Leslie-effect simulators.
Why is the 122 synonymous with the Hammond Organ?
The king of the Leslie speaker line was, and still is the Leslie Model 122, which was specifically designed for older Hammond Tonewheel Generator console organs. These organs were equipped with two 61-note playing manuals, either 25 or 32 pedals, and were produced from approximately 1934 to 1974. Early Hammond's were actually very unique instruments, in that they were designed with a balanced-line or 'G-G Terminal' preamp output, as opposed to an unbalanced / grounded audio output which was common in other equipment at the time, and is the general standard today.
The 122 was designed by Leslie to replace or in some cases augment the original Hammond Tone Cabinet used with the organ. Leslie Connector Kits were devised to allow easy connection of the organ with the Leslie and the Hammond Tone Cabinet. The kits allowed the organist to select either speaker cabinet individually or both simultaneously. This feature allowed an organist to play a varied music program and was a particular favorite of professionals.
When did the B-3 and Leslie 122 become the preferred pair?
In 1955, Hammond introduced the B-3, C-3 and RT-3 console models, and additional console models A-100 and D-100. These new models featured many improvements from earlier models and included the now-famous Hammond percussion feature. They were all equipped with the same revised design balanced-line output preamp (AO-28 series), but the A-100 and D-100 models included internal or 'self-contained' speakers, thereby they did not require a Hammond Tone Cabinet. The A-100 and D-100 also featured built-in reverberation units, so the two-channel Leslie model 251 was generally selected for these organs.
Leslie Connector Kits were designed for the newest balanced-line preamp output organs and most other Hammond console and spinet models allowing the classic 122 sound to be heard with almost any Hammond. Once the B-3 and C-3 became available, the die was cast! They were generally equipped with Leslie 122 series speaker cabinets and the rest is history.
What was the purpose of the Balanced-Line Output from the organ?
Hammond's decision to use a balanced-line output became an important ingredient in the long-term viability and acceptance of the Hammond organ. It was an ingenious design which solved acoustic and audio related problems common in early vacuum tube amplifier equipment. The balanced-line output was used in the early Hammond organs and Hammond Tone Cabinets as a means to reduce 60 Hz hum pickup and other inductively picked-up noise which would otherwise have resulted due to the AC power and audio being contained in the same parallel cable run between the organ and the speaker cabinet. The balanced-line output also significantly reduced audio loss on long cable runs.
This unique technical feature of the early Hammond console organs is still the basis for optimum performance in live stage, studio and other uses. The classic B-3 and Leslie 122 are virtually unaffected by common studio and stage acoustic problems such as light dimmer buzz, AC power hum and grounding irregularities in stage power.
How did a Leslie 122 connect to a Hammond?
Since the Leslie 122 was designed to be used as an additional or replacement speaker for the early Hammond console organs, it utilized the existing Hammond 5-conductor (5/6) or 6-conductor (6/6) cable (# of male pins / # of female sockets). With the aid of a simple Leslie Connector Kit, the Leslie 122 soon became a direct-replacement for the Hammond Tone Cabinet and offered tremendous improvement in sound. The Kit was installed in these organs to facilitate Leslie motor speed switching from a switch mounted on the organ. If a Hammond Tone Cabinet was also used, an Echo Kit was installed to allow for either the Leslie or the Tone Cabinet to be played individually or together. Some later organ spinet and console models (Series L-100, M-100, H-100, etc.) had Leslie Kits custom designed to allow connection to the 122.
The balanced-line console organs best suited for the Leslie 122 were Hammond organ Models:
A, AB, B, BA, BC, C, AV, BCV, BV, CV, DV, A-100, B-2, C-2, B-3, C-3, D, G, D-152, RT, RT-2, RT-3
As mentioned above, although Hammond Models A-100 and D-100 console models were designed with self-contained speakers, they also contained an AO-28 series organ preamplifier which was used in the B-3 / C-3 models. Along with essentially similar manuals, tonewheel generator, percussion and vibrato / chorus system, this is the reason why these consoles sound so similar to a B-3 and should be carefully considered for purchase!
Can my L-100 be connected to a 122?
Almost any organ could be connected to a 122 with the proper connector kit, but the 122 was tonally and electrically designed for the Hammond balanced-line consoles. Although other Leslie models could be used with balanced-line organs, they were designed for other models and other manufacturers. Contrary to belief, not every Leslie was designed for a Hammond, just as not every Chevrolet is a Corvette.
What's a Leslie 147? How is is different from a 122?
The Leslie 147 is a fine Leslie model also commonly used with B-3's and other consoles. It is essentially similar to the 122, except that the model 147 amplifier was not designed for balanced-line organs, but was instead designed for a variety of standard 'grounded audio' or 'unbalanced' audio output organs, including many Hammond organs with self-contained speakers and certain other manufacturers organs. When used with an older balanced-line Hammond, and wired in a 'G to Ground' or unbalanced configuration, the 147 is very susceptible to hum, light dimmer buzz and other background noise. Therefore, it is an especially poor choice for recording studios, live television or other uses requiring a constantly miked Leslie.
However, the 147's unbalanced design makes it a great universal model Leslie for use on almost any type of organ or keyboard. The 147 has an inherently brighter and harsher sound when compared to the 122 due to a very different amplifier internal design.
TO CLARIFY A COMMON MISCONCEPTION ----- The 122 series and 147 series and all internal components are actually identical except for the amplifier! A 147 can be converted to a 122 by simply removing the amplifier and sliding in a 122 amp. Remember, they are mechanically similar, but acoustically very different!
What about the Leslie 122 and 147 RV (reverb) MODELS?
Some 122 and 147 models with reverberation were denoted with an 'R', 'V' or 'RV' in the model number. These older reverb-equipped models are essentially similar, but they had extra routed wooden 'flutes' or slots in the cabinets, which were smaller than normal and located beneath the larger upper slots. It is not advisable to use or attempt repair on early Leslie reverb amplifier units as these Leslies did not mix the reverb through the rotary horns. Instead they utilized a 6' X 9' Speaker for a dry reverb signal. There are far better reverb options including new high-gain spring reverb units which mount in the organ and offer complete control of the amount of Reverb. For keyboard players using a Leslie with a Pedal Preamp, a digital or spring reverb unit can be added in-line prior to the pedal preamp for excellent reverb through the Leslie rotary horns. Reverb units, percussion add-on kits, pedal preamps, and many other accessories are included in our ON LINE Catalog.
What were the Leslie Models 142 and 145?
The Leslie model 142 was actually a complete Leslie 122 housed in a shorter cabinet. The amplifier was marked '122', but the shorter cabinet style denoted it as a 142. There were NO other technical differences, although acoustically, the 142 lacked the very low-end bass response of the 122 since the bass enclosure was smaller.
The Leslie 145 was a complete 147 also housed in the same shorter cabinet as the 142. The amplifier was marked '147', but the shorter cabinet style denoted it as a 145. There were no other technical differences between the 145 and the 147, except that the 145 also lacked the very low end bass response of the 147, again due to the shorter cabinet and correspondingly smaller bass enclosure. Both the Leslie 142 and 145 are excellent choices for purchase / rebuilding for touring, especially when used with keyboards or MIDI Modules.
So -- which model Leslie do I choose?
The 122 Series Leslie's are still the model of choice when used with the older Hammond 'balanced-line' organ models listed above. Many professionals also use them in conjunction with pedal preamps and digital keyboards to achieve the mid-50's 'mellow' Hammond sound from their keyboard. The Hammond XB-2 keyboard used in conjunction with a Leslie 122 will provide the mellower 'Blues / Jazz / Gospel / Country ' Hammond sound better than other models. However, an XB-2 used with a 147 will provide a brighter and 'harsher' Hammond sound for Rock music. Either Leslie will perform well, but organist and keyboard players should carefully consider their needs and all of the options before purchasing anything. We can assist in selecting a Leslie or creating a package for special needs, and tell you what other professionals or bands have selected for their own use.
Tips for the Best Hammond Sound from a Keyboard or MIDI Module
Virtually every keyboards and MIDI Modules tend to be too 'bright' in their digital Hammond drawbar samples, and as such should be equalized down when possible. As a technical reference, the Hammond B-3 had a maximum Tonewheel Generator frequency of slightly less than 6000 Hz, making it a mid-range instrument! For the best Hammond sound from keyboards or MIDI Modules, remember to EQ or mellow them down, turn off any digital chorus or vibrato, and use a Leslie or a true Rotary Horn Unit. No rack mount simulator will ever deliver the true sound of a Leslie.
General Technical Information on New Tube Amplifier Leslie Model Series 122 and 147A
The new Leslie 122 Series and 147A are still essentially similar to their predecessors. However, due to changes in motor design, the amplifiers have been slightly modified and the new Leslie's utilize a newer-style motor requiring a Motor Control Circuit Board. The new 122 Series and 147A amplifiers still feature 12AU7 tubes and 6550 amplifier tubes for the classic performance and sound of their predecessors. The 6550 is world-renowned for warmth and is an integral part of the classic Hammond and Leslie sound. The amplifier develops approximately 40 watts of power, and is essentially similar to the original amplifiers in operation and performance. Due to the 6550's long history of being the performance standard for Leslie amplifiers, GOFF Professional utilizes our own excellent quality, privately labeled 6550 tubes for all of our touring and professional equipment. We offer these same 6550's (as well as all Hammond and Leslie tubes) through mail-order. Our 6550's are also used by many guitar players in their vintage tube amps.
The new Leslie 122 Series and 147A are available in either 120 VAC, 60 Hz, or 220 VAC, 50 Hz versions, and can be ordered in several cabinet and amplifier configurations, including walnut or black-textured finish, 6 or 11-pin amplifiers, etc., which are listed below in the specifications. Custom blanket covers, Road cases, and other custom options are available.
Original Leslie Tube Amplifier Models - Speaker Selection and Type
The original Leslie 122 / 147 Series and other original tube models utilized a Jensen 16 ohm upper horn speaker (driver), rated at 40 watts. The 15' woofer was also 16 ohms, rated at 100 watts. Several woofer styles were employed throughout the model years, but all were were designed to meet the original performance specifications.
The upper driver, woofer and tube amplifier's 16 ohm output transformer were specially designed to be used as an integral group in conjunction with the original 16 ohm, 12 dB per octave, 800 Hz crossover. This overall design philosophy is the heart of the classic tube amp Hammond / Leslie sound, and cannot be altered without changing the original sound! Before you spend money on high-power alternative speakers / drivers, consider that the vast majority of touring professionals use these same components in their equipment.
Original Solid-State Leslie Models - Speaker Selection and Type
Some later solid-state Leslie models used lower impedance upper speaker drivers and woofers (8 or 4 ohm) to take advantage of the solid-state amplifier's increased power handling characteristics. Although similar in appearance, these lower impedance drivers, woofers and crossovers are not interchangeable with tube amp models! Damage may result to the equipment if they are used. The crossover designs in solid-state models also varied, as they were generally designed in the preamplifier stage of the Leslie. Throughout the many solid-state Leslie models, each model group had differing equipment installed to meet the specific design of the Model.
The classic Hammond / Leslie sound is extremely dependent upon the correct equipment being installed! The new 122 Series and 147A tube amplifier Leslie models retain the original design characteristics and will deliver the classic 'sound-in-motion' synonymous with the name Leslie.
Speaker Selection and Type
An improved high-efficiency 16 ohm upper driver and 16 ohm long-throw woofer are employed in new Leslie's to take advantage of engineering and production material improvements for maximum efficiency, although the original styles will substitute perfectly. The new upper driver is conservatively rated at 40 watts, however it is actually quite capable of handling 60 watts with proper crossover and woofer installed. The new 15', 16 ohm woofer features a custom long-throw basket and original-style rolled paper cone for optimum low frequency response, especially at lower power levels. The 15' woofer fires directly into a motor-driven, one-piece hard-foam bass-rotor.
GOFF Professional strongly recommends against changing the stock Leslie upper driver or woofer to an 8 ohm replacement or other 'high-power' speakers when used in a tube amplifier powered Leslie. This is a very common error which is costly and simply the wrong thing to do! The classic sound is extremely dependent upon the correct mix among the tube amplifier's 16 ohm transformered output, 16 ohm Leslie upper horn driver and 16 ohm woofer. All of our touring Leslie 122's and 147's use our 16 ohm components and original new or rebuilt tube amplifiers.
Our new Leslie crossovers are built to the original design specification 12 dB per octave, second order 16 ohm crossover, with an 800 Hz crossover point. The crossover design is a critical ingredient to maintaining the classic sound!
Original Leslie 122, 147, etc. Parts, Repair Service and Amplifier Rebuilding
GOFF Professional offers mail-order parts and repair service for most early Leslie tube amplifier, selected solid-state models and for ALL new Leslie products. We offer complete Leslie tube amplifier rebuilding service for early models as well as new original-replacement amplifiers, tubes, belts, new upper drivers, woofers, bearings, plastic horn assemblies, service manuals, etc., and offer single-speed Leslie conversion kits to update an older single-speed Leslie to 2-speed operation. Contact us for parts and service, or for complete new and rebuilt Leslie's. We can customize a complete touring or church package for your special needs.
Some of the very earliest single-speed model Leslie's utilized a woofer with a high-voltage DC coil for extended bass response. These models were produced before the introduction of large permanent magnet speakers and are generally not recommended for rebuilding for home or professional use without replacement of the amplifier and upgrade of the speakers. A 2-speed motor conversion kit is available which does not require replacing the motors.
Leslie Pedal Preamps
Any 1/4' output device (Keyboard, MIDI Module, etc.) can be played through a 122 Series, 147 Series or most other 6, 9, and 11-pin Leslie Models if a Combo Pedal Preamp is used. The Trek-II Model UC-1A Combo Pedal Preamp has 1/4' input and Leslie cable output, and 'Stomp' style footswitch control of Leslie motor switching. Specific Pedal Preamp details and specifications are contained elsewhere in our On-Line Catalog.
SPECIFICATIONS - New Leslie 122 Series & 147A
- True Mechanical Rotating Upper Horn / Rotating Bass Rotor - NOT a Simulator!
- Classic Vacuum Tube Amplifier - 40 watts RMS, 16 ohm transformered audio output
- 16 Ohm Upper Speaker (Driver), Conservatively rated at 40 watts
- 15', 16 Ohm Woofer, Long-throw - Rated at 100 watts
- 12 dB / Octave, 16 ohm Crossover, 800 Hz crossover point
- Two-Speed Operation for Chorale (Slow), Tremolo (Fast); 'Off' available on some models with some new Hammond organs / keyboards
- Power - 120 VAC, 60 Hz, or 220 VAC, 50 Hz versions available
Leslie 122 Series / 147A Ordering Information
- 122A, 147A - Walnut Cabinet, 6-Pin Leslie Connector on amplifier (for B-3 and similar original organs), new 30' Leslie cable included, specify 5/6 or 6/6 cable when ordering
- 122XB - Walnut Cabinet, 11-Pin Leslie Connector on amplifier for Direct Plug-In to Hammond XB series organs and Hammond XB-2 Keyboard, new 11-pin 30' Leslie cable included
- NOTES: Leslie Connector Kits are available which allow the use of the above listed Leslie Models with most early tonewheel generator and newer Hammond organs. Depending upon specific organ and Leslie models, separate channel mixing and selection may or may not be available.
A Pedal Preamp will allow these Leslie's and most other 6, 9 and 11-pin Leslie models to be used with any keyboard or other 1/4' device, however no provision is made for separate channel mixing or selection in multi-channel models.
Some Leslie models are especially suited for certain Hammond Organ models. Some early Model Leslie's cannot be easily connected to Hammond organs or other manufacturers organs or keyboards. Email or call GOFF Professional with your specific needs.