Jonny’s Palme (stringreunited).
Introduction
The Ondes Martenot (or at least Ondes Musicales) is an instrument unique due to its control mechanisms and waveforms. As one might hope, its diffuseurs, or speakers, live up to the uniqueness of the instrument and bring further distinction to the instrument. There are four main types of diffuseur - Principal (standard loudspeaker), Résonance (springs suspended in front of speaker), Metallique (gong used as speaker cone), and Palme (suspended strings allow for sympathetic resonances). This article will discuss how to reproduce the sounds of the Palme, and briefly also the Résonance.
The Palme gets its name from its distinctive shape, which is similar to a palm leaf. The leaf shaped part is actually a resonating space, much like the body of an acoustic guitar, in front of which strings are suspended. It features a total of 24 strings, 12 on each side of the diffuseur. Each set of twelve is generally tuned to a full chromatic scale, ascending by semitone from left to right, though some pieces call for alternate tunings. The back strings may be tuned an octave above the front ones (I’m not quite sure). The Palme speaker was not only used by Jonny in conjunction with his Ondes Martenot, but also on Thom’s vocals on You And Whose Army.
The first thing to ask is how much do you want an authentic Palme?
The Résonance Diffuseur
Martenot essentially “replaced” the Palme with the Résonance diffuseur in the 80’s. It uses springs stretched in front of a speaker to create resonance and reverberation. Dierstein’s new Ondes Musicales uses this Résonance (in its double cabinet with the Principal) instead of the Palme, and since obtaining his new Ondes Jonny has used the Résonance instead of his more delicate, temperamental, and irreplaceable Palme. That could be easier to reproduce than the Palme, since you do not have the added problem of reproducing the resonant cavity, and you do not need to keep any strings in tune (if the strings are out of tune, your resonances would only be strong when you play out of tune). It wouldn’t be quite the same as the Palme, but it could be easier to make while still being quite an interesting Martenot diffuseur.
You could also just go for an authentic or even digital spring reverb, which doesn’t function in quite the same way but produces somewhat similar sounds.
The Palme Diffuseur
While the most distinctive physical characteristic of the Palme is its shape, what makes it unique sonically are tuned strings that are suspended in front of and behind the soundboard. The strings are originally tuned to the notes of a chromatic scale, but theoretically one could tune them alternately. The strings produce sympathetic resonances with the sounds being produced by a sound-exciter (or resonator) located in the “stand” under the chamber. Its the same principle as the extra strings on instruments like the Sarangi, or even on a piano when one releases the dampers.
Both sides of an early Palme (cité de la musique paris).
The cavity of the “leaf” also gives the speaker a resonant space, much like the body of an acoustic guitar. The resonant sounds produced by the strings are amplified by the sound chamber, and also caused to resonate for longer. As such, it is very important to the Palme’s overall sound.
If you wanted a really simple, makeshift Palme, you could buy a really cheap sound-exciter (such as this) and connect it directly to the bridge of the instrument. You could also trying sticking a speaker inside of the guitar, but it’d be less accurate to the original. With a twelve-string, you could even try to cover the entire chromatic scale, though I would be careful of the tensions. You should probably tune the strings down in pitch, rather than tuning any to higher pitches, lest you risk breaking the neck.
For a more authentic Palme, you’d need to build or commission a similar cabinet. The “body’s” shape is vaguely ovular, but with a point on one end, and suspended by a base. The base is also fairly important, as it is where the bridge/tailpiece and sound-exciter are located. If you were to have a cabinet constructed, I would think that a luthier would probably be a better option than a carpenter.
The base of the cabinet suspends the body above the bridge/tailpiece, so that the sound-hole is near the center of the span of the strings. This is a major difference compared to most string instruments, on which the bridge is connected tot he sound-chamber and can influence it directly, but you may or may not deem it necessary for your copy.
There seem to be two bridge types, one with a single square of metal, which is shaped to both hold the strings and to direct them, and one vaguely similar to those seen on a guitar such as a Les Paul (separate “bridge” and stoptail). Jonny’s Palme is of the latter type, but it seems to be a characteristic of later (80’s) Palme’s.
There are also two different methods of suspending the strings, or “tuners.” Earlier models have the tuners based on the top of the instrument, while later models have them held through the soundboard(s). This change was made earlier than that from one bridge to the other, and so models exist with the earlier bridge, but the later string-suspension-position.
(Same sources as above).
A Palme with the earlier bridge-type, but the later tuners (Source).
The strings used for the Palme were metal and similar to a guitar’s or mandolin’s, so one could just use guitar strings for a copy, and therefore possibly even a twelve-string guitar’s bridge and tuners. A 12-string Tune-o-matic style setup could work well, as could something closer to what is found on Arch-top guitars.
The Palme does not actually use a speaker, but rather a sound-exciter - basically the transducer part of a speaker, its voice coil, pole piece, and magnet. The exciter is connected directly to the bridge of the Palme (or to the bridge/tailpiece combo of the earlier models) by a length of metal. This causes the bridge itself to vibrate, in turn causing the strings to do so.
Though not quite the same, modern alternatives are available from Monacor and Sparkfun.
A side-view diagram of a Palme (radiomuseum.org).
An image of the a Martenot’s sound-exciter/resonator, from the Metallique diffuseur (radiomuseum.org).
Summary
It seems that the fundamentals of a Palme are these:
- Cabinet with acoustic amplifying/resonant space.
- Strings suspended in front of the sound-hole of that space.
- Bridge on which the strings rest is directly connected to a sound-exciter.
- Sound exciter and bridge kept in a “base,” which holds up the amplifying space but keeps the exciter and bridge separate.
If anyone ever does build a copy, I’d be happy to see and hear it. Best luck!
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Existing Copies
Just as the limited availability of authentic Ondes Martenot has caused many copies to exist, there are already a few copies of the Palme out there.
Claude-Samuel Levine’s Palme is similar to later Palme diffuseurs, but shows some notable differences from other Palmes, specifically in the “bridge.”
The Japanese company Asaden have also created a Palme copy. It is quite different from either of the originals in how the strings are suspended, but the fundamental principles are the same (resonating strings suspended in front of a sound chamber), and apparently it is much easier to tune. It only features strings on the front half of the diffuseur. You can listen to it here.
