Ken Griffin (Organ Special Effects)

Aside from the instruments Ken Griffin played, two other aspects of his music make the "Griffin Sound" unique. One of these is the way in
which he treated the apparent acoustic environment of these electronic organs, particularly the Hammond. If you listen carefully to his
recordings, you will notice that there are several different types of echo or reverberation effects in the background which give the auditory
illusion that Ken was playing in various types of halls or other enclosures. Because these effects greatly compliment his music, they
become a part of his final musical result. It is also a well-known fact that the way a musical instrument sounds and responds greatly
influences a player's actual performance. The second aspect of the "Griffin Sound" is his clever and creative use of a recording technique
known as overdubbing.
As far as I can determine, Ken Griffin was a pioneer in the use of a subtle but very interesting effect comprising a distinct, rapidly repeating echo in the background. Such an effect greatly enhances many types of rhythmic popular music, which is what Ken primarily played. Other organists and many other musicians have used these repeating echo effects, and indeed such effects are an important part of some of today's popular music, but to the best of my determination, nobody ever used that effect with an electronic organ until Ken began to do so.

In listening to Ken's very early recordings, I do not hear that effect, so the conclusion is that he was perhaps either not aware of the effect, or maybe it had not yet been discovered when he began to make recordings. But the effect is prominent on a number of selections on many of his subsequent records, particularly the LPs produced by Columbia Records. Some research, which I undertook recently on the Internet leads me to believe that the repeating echo effect became available sometime during the early 1950s, however this is my personal opinion and should be accepted as such and not as absolute fact. I have discovered no evidence of any earlier use of the repeating echo effect so far.

At this point, we should insert a clarification of terms. Although the terms echo and reverberation are frequently used interchangeably, they are different. An echo is a delayed, distinct repetition of a sound, usually caused by the reflection of the sound wave from a distant surface. Reverberation is a more or less continuous combination of multiple individual reflections and as such results in a gradually decaying prolongation of a sound after the sound source has ceased. Reverberation does not present a distinct repetition of a sound.

On some of Ken's early recordings, there is an unusual type of reverberation, a rather hollow, bouncy and sometimes "booming" effect which is particularly prominent on the pedal tones and lower manual pitches, and which gives the illusion that he was playing in a rain barrel. Now, what were these effects and how were they produced? Many of his later recordings have a smooth and very natural reverberation effect which sounds as though Ken were playing in a large hall.In actuality, Ken did most of his playing (for recording purposes) in studios, and the electrical output signals of the various Hammonds that he used went directly into the recording equipment with no microphone involvement whatsoever. A little thought about this would then indicate that if he recorded the direct electrical signal from his Hammonds, then there could be no reverberation or other room ambience effects possible, and yet such effects are present on his recordings. How, then, did he do this?

The first effect, in all of his early and some of his later recordings, is that somewhat hollow, rain-barely type of reverberation, which I mentioned above. This came from a unique and ingenious Hammond invention called the fluid column reverberation unit. It was developed early on in Hammond history because the relative compactness and ease of installation of a Hammond as opposed to a real pipe organ meant that many Hammonds found their way into private homes, small chapels, or funeral parlors, places in which the fine acoustics.

The people at Hammond quickly realized that reverberation was an extremely important contributor to the general majesty of many organ tonalities. A lack of this most vital characteristic meant dull, lifeless and uninspiring sound, something that the Hammond people certainly did not want for their products. Therefore, realizing the importance of reverberation and the fact that many Hammonds went into small and non-reverberant rooms, the Hammond research staff developed the fluid column reverberation unit to add a pseudo reverberation effect to any Hammond that might find itself in a relatively small and therefore, acoustically "dead" room.

This first illustration shows a general view of a fluid column reverberation unit. The device is about 3 feet tall and consists of a network of 5 coil springs, roughly two and a half feet long. Three of these springs are contained in brass tubes which are filled nearly to the top with a non-evaporating light oil. The first spring is entirely in air, and the last spring is mostly in air, but a small portion of one end is likewise enclosed in a shortoil-filled tube.

Here is a close-up of the top of the reverberation unit. The rounded, black device is a driver unit, very similar to an ordinary loudspeaker, but without its characteristic paper cone. Immediately below this driver unit is a triangular stirrup with a freely moving lever. The two springs which are either free of oil or only slightly immersed attach to opposite ends of this lever. The stirrup itself is stabilized and
maintained approximately in position by two other springs which are almost entirely immersed in oil. The fifth spring, also immersed in oil, connects to another lever above the driver unit (not shown) and balances the pull of all of the others.

Here, at the bottom end of the spring which is entirely in air, there is a crystal pickup unit, which is the round metal element to the right in the picture. You can see the bottom end of the spring attached to a hook on the pickup.

In operation, a small portion of the amplified electrical signal from the organ goes to the driver unit, which then imparts an up-and-down mechanical replica of this vibration into this network of springs. Sound travels along springs such as these at a considerably slower speed than it travels through air, thus a spring of this type can introduce a slight delay. Furthermore, the springs, once started into
vibration, will continue to vibrate for a while even after the signal to the driver unit stops. Therefore, we can see that this network of springs produces both a slight delay and also a prolongation of any signals which activate the driver unit.

The crystal pickup converts the mechanical vibration of the springs back to an electrical signal whichis amplified and combined with the original direct signal from the Hammond console. The result of this is the production of a reverberation effect, somewhat like that obtained in a large room. As a pioneering device, the fluid column reverberation unit contributed much to improve the overall sound of these early Hammonds, particular in a recording environment, where, for the first time, a somewhat natural reverberation or room ambience effect could be applied to the music of an electronic organ. It also served as the basic model from which both the Hammond company and others developed better reverberation units, because it quickly became evident that the device made a significant improvement in the tone of any Hammond (or other brand of electronic organ) which was installed in a home or otherwise acoustically inferior environment.

In spite of their contribution to the tone of the Hammond, the early fluid column reverberation units had several drawbacks. First of all, they worked much better on lower frequencies than high ones, which added a somewhat hollow and booming sound to the music, adding significant amounts ofreverberation to bass and midrange tones while adding almost nothing at all to the life-giving higher frequencies. Second, the spring network had certain frequencies at which it was mechanically very resonant. These frequencies would then be artificially accentuated, resulting in an overall uneven frequency response with several pitches much louder than others. Still, it was definitely an improvement over the directly recorded sound of an electronic instrument without any reverb at all.

The light oil which surrounded some of the springs was for mechanical damping. Without the fluid, the reverberation would be overwhelming and would last for thirty or more seconds, entirely obliterating the music and making the unit useless. The two side springs on the stirrup, and the single spring which connected to the far end of the top lever above the driver unit were only intended to stabilize and mechanically balance the system and were not intended to contribute anyreverberation effect. By surrounding these springs with oil, the Hammond people ensured that these springs did not add to the reverberation effect, because the oil damped out virtually all of their vibrations.

The primary producer of reverberation was the long, dry spring that went from the front end of the lever in the stirrup to the hook on the crystal pickup. Associated with that spring was a second spring, mostly surrounded by air, but having its opposite end immersed for several inches in a short, oil-filled tube. This spring also contributed reverberation, since the vibrations of both of these springs communicated back and forth through the lever in the stirrup. The short oil-filled tube provided damping for the reverberation and the actual amount of reverberation decay time was controlled by the level of oil in the short tube. By adding or removing a small amount of oil from the short tube, the musician could vary the overall reverberation decay time.

In addition to this, there was a metal pin stuck between two turns of this slightly damped spring. The pin was generally inserted about an inch above the point at which this spring entered the short oil tube. This was called a reflecting pin, and its purpose was to cause some reflection of higher frequency vibrations, so that the already weak higher frequencies in the reverberated signal would not be excessively damped out by the oil in the short tube.

After a while, Hammond developed a vastly improved reverberation unit, referred to as the necklace unit. It got that name because it had three springs entirely in air that hung down in roughly parabolic loops and resembled the shape a chain necklace forms on a woman's neck. The three springs of the necklace unit actually consisted of two separate springs, joined rigidly end-to-end at the center of the parabolic loops. Each of these two springs was wound in opposite directions. Also, the wire used was considerably finer than that used in the springs of the early fluid column units, and the drivers and pickups were different also. The new drivers were much smaller and therefore had much less mass. Also, they introduced reciprocating rotary motion into the springs rather than up-and-down motion as in the fluid unit.

Each of the three spring loops in the necklace unit had its own pickup and driver element. The difference in sound between the fluid unit and the necklace unit was profound. The necklace unit had a much flatter frequency response, and it also responded well to the highest frequencies that a Hammond could produce. It did have certain mechanical resonances and did accentuate certain pitches above others, but these were much less pronounced than the resonances of the fluid column unit. Many believe, myself included, that this was one of the best spring reverb units ever devised, and certainly the best one that Hammond ever made.

It did, however, have a couple of disadvantages. First, it was delicate, and secondly, it was susceptible to external vibration. If people started dancing in the same room where the tone cabinet containing such a device was located, the resulting vibration could make the parabolic spring loops swing around enough to bump into the mounting bracket for the unit resulting in crashing and banging sounds coming from the speakers. Nevertheless, as long as the unit was isolated from excessive vibration and handled carefully, it produced a very natural, concert-hall-like reverberation effect in the music. It is very likely that on those Ken Griffin recordings that have a very natural sounding reverberation effect where it seems as though Ken was playing in a concert hall, the organ was equipped with the Hammond necklace reverberation unit.

In later years, the Hammond company came out with an "improved" reverberation unit. It had two sets of double springs, again wound in opposite directions and also of different wire size and turns per inch. Both spring sets were under slight tension and were installed in a flat, metal chassis that looked very much like the boxes that neckties come in. It was, therefore called the necktie-box reverb unit. Like the necklace unit, it had rotary-motion drivers and pickups of very small size and low mass, resulting in good high frequency response. However, it tended to have a more "springy" and a less natural reverberation sound than the necklace unit. As far as we can determine, Ken had already died before this unit was in general use.

Now, the interesting repeating echo that we hear on many of Ken's recordings is an entirely different effect. Such an acoustical effect does occur in nature, but only in some very unusual environments. We can get a rapidly repeating series of distinct echoes under stone arch bridges, and in certain domed-ceiling rooms if we stand right under the center of the dome. It is also possible to get such an effect in a long and narrow hall if the hall has hard reflecting surfaces at each of the narrow end walls. A variation of this effect also occurs in the announcements made over the PA systems in some large sports arenas where there are many distant loudspeakers as part of the public address system. Most typical enclosures and rooms do not produce this effect. However, for recording purposes, there is a relatively easy way to create this effect, and that is tape echo.

When tape recording really came into its own, at some point tape echo was discovered. I can find no information on who discovered this effect or how he discovered it, but it seems logical to think that it was an accidental discovery that some recording engineer made through an erroneous connection in his recording setup, and either he or some musician probably said, "hey, wait a minute! I like that effect!"

Tape echo, as the name implies, involves the use of a tape recorder. In order to make a repeatingecho with a tape recorder or tape deck, there are two conditions which must be met. First of all, the machine must have independent record and playback tape heads. Cassette decks, for the most part, and most home use reel-to-reel tape decks have only one dual-function record/play head. These machines cannot produce tape echo. The second requirement is that the deck must have separate recording and playback preamplifiers, or, in other words, the machine must have the capability of being able to monitor the recorded signal on the tape while the machine is actuallymaking a recording.

The following illustration is an elementary diagram of such a tape recorder. Following standard symbology, we have used triangles to represent amplification stages. The drawing shows (the bottom line) a length of tape moving from left to right, being pulled past three tape heads by the pinch roll and capstan at the right. From left to right, the first tape head is the erase head, which erases any previously recorded signal on the tape. The next head is the record head, which we show here receiving an electrical signal via its amplifier from in this case, Ken's Hammond.

The third tape head is the playback head, from which the (just) recorded signal on the tape can be picked up, amplified and fed to the speaker (item 8). Now, any time that we play a note on the Hammond, it will be recorded onto the tape by the record head. In a very short time, as the tape moves from left to right, that signal on the tape will pass under the playback head, and it will then appear at the speaker.

Therefore, we will hear an "echo" of that note, delayed from the actual note by a certain amount of time, that time depending on the physical distance between the record and playback heads, and also on the speed of the tape. In a very typical situation, the distance, center to center, between the record and playback heads might be one and one eighth inches. The tape speed could be seven and one half inches per second, a very common speed for many recording applications. If these conditions prevail, i.e. 1 1/8" between heads and 7.5 inches per second tape speed, then the time between the actual playing of the note on the Hammond and the production of the so called echo will be 0.15 seconds.

Notice that as it now stands, there will be one delayed echo repeat for every note that Ken plays on his Hammond. If we wind up the tape and then listen to the playback, we will hear what Ken played, but it will have no echo effect. The next thing that we must do, therefore, in order to create multiple repeat echoes, will be to create a feedback loop from the playback head amplifier to one of the inputs on the record head amplifier. Now, if Ken plays a note on his Hammond, after a time lag of 0.15 seconds, that note will be played back, as before. However, since we have connected a feedback to the record head, that same signal will be recorded onto the tape again. And, as before, when the tape has moved ahead so that this newly recorded first repeat is under the playback head, it will be played back a second time. If we were to wind up the tape now, and then play it back, we would hear Ken's original note followed by one echo repeat, which would have
been recorded on the tape.

By adjusting the gain of the feedback loop correctly and at some level which is always less than unity gain, we can have this re-recording take place several times. For example, if we set the gain at 50%, then when Ken plays a note on his Hammond, after 0.15 seconds, it will be played back, we'll hear a repeat at 50% of the original volume from the speaker, and it will again be recorded on the tape, and then after another 0.15 seconds, it will be played back a second time, but at 50% of the volume of the first repeat or 25% of the original level. Likewise, it will be recorded onto the tape yet again, only to be replayed a third time, and again at only 50% of the previous repeat or 12.5% of the original. This process will continue until the signal level drops to inaudibility.

In this manner, we can derive a repeat echo effect for any note or notes that Ken might play on his Hammond, and we can have multiple repeats, or echoes, of this sound, and have each repeat quieter than the preceding one. There is one more consideration that we must be aware of to complete this process, and that is shown as the square box marked high-pass filter. The high pass filter does exactly that. It passes the higher frequencies but blocks low frequency signals. A repeat echo effect greatly enhances many types of pops playing and many Hammond organ effects, but it sounds very bad and can severely mess up the rhythm of a song if the repeat echo is allowed to affect the bass pedal tones. Therefore, we use a high-pass filter in the feedback loop so that the low frequencies will not be re-recorded onto the tape.

Remember that the very first repeat that we hear during the recording is actually the initial recording itself. This will have full pedal bass. However, the first re-recorded signal, which is the first actual echo signal on the tape must not have any bass in it. When we wind up the tape and then listen to the recording, there will always be one less echo repeat on the tape than the number of echo repeats we heard when making the recording.

The high pass filter, then effectively keeps the echo effect away from the pedals and allows it only to affect the mid-range and the high range frequencies. If you listen carefully to those Ken Griffin recordings where there is repeat tape echo, you will notice that there is never any repeat echo effect on the pedal notes.

Compared to spring reverberation devices, tape echo has several advantages. First of all, it has a much flatter frequency response, so that it does not severely accentuate certain pitches and make them disproportionately louder than the rest of the pitches or notes of the instrument. Second, it has good high frequency response and can adequately echo even the very highest audio frequencies that the music may have. By changing the tape speed, we can easily produce different echo repetition rates. By adjusting the amount of gain in the feedback loop, we can change the total echo time easily by simply turning a knob on the tape deck's control panel. Compare this to adding or remove oil from the short damping tube of the fluid column reverb unit, and the complete lack of reverberation decay time adjustment on either the necklace unit or the necktie box units.

During the fifties through the seventies, a number of musical instrument companies made specific tape units solely dedicated to echo production. These units were sold under many different names, one of the more well known being the Echoplex unit. However, any semi-professional or higher grade commercial tape deck with independent record and playback heads and amplifiers could function as an echo unit as well as a tape recorder. I have not yet been able to determine if Ken used the actual recorder upon which he made his master tapes as an echo producer also, or whether he had a separate tape echo machine added.

But in either case, that is how he produced the interesting and very effective repeat echo effect that we hear in songs such as Cruising Down the River, Barcarolle, Kringle's Jingle, Jealous, Marie, and numerous others. On several numbers, he uses a slower echo and actually plays in step with the echo, so that the echo repeats add an after beat to the music. His version of Ferry Boat Serenade comes to mind as an excellent example of a slower repeat echo in which the echo repetition rate is the same as the tempo of the song. It is possible that he may have had the tape running then at 3.75 IPS, which on a machine with heads 1 1/8" apart would give an echo repeat every 0.3 seconds, or a tempo of roughly 200 beats per minute (as a 2/4 march or polka) The actual beat count would be 200 quarter notes per minute, but the appropriate metronome setting would be half that or 100 beats per minute (double time).

The above picture is a close-up of the actual headblock of a tape deck with tape echo capability.It illustrates clearly the three tape heads showing from left to right the erase head, the recording head, and the playback head which in this machine has an extra metal magnetic shield around it.

In today's modern recording era, we now have extremely versatile digital signal processors which can produce all types of repeat and delay echoes as well as multiple types of reverberationeffects. However, in Ken's time, he achieved these same effects by the means I have just described.

Overdubbing, the other recording trick which Ken used occasionally, refers to recording a song once, listening to it while simultaneously recording an additional part, so that the final playback contains both recordings playing together. The same effects could be achieved by two performers on two separate Hammonds, however overdubbing allowed Ken to do the extra part himself. In his version of the song Cruising Down the River, Ken uses overdubbing to add the simulated xylophone trills and also the high-pitched whistling countermelody. It would be physically impossible for one person to play all of those effects simultaneously, but by adding these effects after the original, it is very easy. Overdubbing accounts for the high-pitched background rhythm accentuation chords in Ken's version of You You You, Love Letters in the Sand, and his version of Dream as it appears on the album Sweet and Lively.

Perhaps the ultimate example of his creative overdubbing is what Ken did in his arrangement of In an Eighteenth Century Drawing Room. Here, he not only overdubbed a second part, but the additional part was recorded at a lower speed and then played at a high speed to create an interesting and somewhat comical pizzicato effect. In order to do this, he first recorded the main portion of the music in the conventional manner. Then he played this back, but at a lower speed. While listening to the low speed playback, he recorded the second part. Now, the immediate result of this was a low-speed main recording with a normal speed accompaniment. When this result was speeded up so that the main part played back at normal speed, then the accompaniment played back at high speed.

The only other example I have ever heard of this technique being applied to organ music was done by the famous theater organist, George Wright, whom many, myself among them, consider to have been the world's premier theater organist. So Ken was in good company! It would be interesting to know which of these two famous musicians was the first to do this. This works, by the way, because the multiple speeds of tape decks are always in a 2:1 ratio. That is, a tape speed of 7.5 IPS is exactly twice that of 3.75 IPS. Likewise, the next higher tape speed of 15 IPS, which is used on many commercial studio machines, is twice 7.5 IPS. Very conveniently, if we double the speed of the tape, the recorded sounds increase their pitch by exactly one octave, since octaves also involve a 2:1 frequency ratio.

In many ways, this shows us that Ken Griffin was a very innovative and creative pioneer on the American pops organ scene. He was perhaps the best known Hammond organ performer of the last century. He developed a deceptively simple yet distinctive style of playing, and he was as far as we know, the first popular organist to realize how important the apparent acoustical background was to popular organ music, and the first to utilize (and alter as necessary) the organ's acoustic environment to suit the music he played at any instant. Many people have tried to imitate the elusive Ken Griffin sound. But to do so with complete accuracy requires not only the use of the same instruments that he used, (tone-wheel Hammond and Wurlitzer electrostatic organs) but also to reproduce by the means I have just described, the instruments' acoustical environments as well, and to resort to overdubbing to add extra parts and effects as necessary.

Just as the famous Les Paul was the pioneer for many of today's modern guitar effects, so too was Ken Griffin the performer who did the same for the electronic organ, and to whom virtually all of the subsequent and well-known electronic organ performers owe at least
some of their techniques.