Topic by skip

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Topic: Questions about the Rhody.

1. I notice that the Global Resonance control has an effect in the Rhody preset, in that when the sustain pedal is used, the notes "swell" in amplitude first, before they sustain. I like it a lot, but my question is: is this authentic in any way? If it is authentic, why does this happen? It doesn't sound like any kind of sympathetic resonance - the notes that are played simply get louder.  If it is not authentic in any way, I don't care - I'm just asking out of curiousity.

2. With the sustain pedal down again, there is a kind of "sympathetic resonance" in that when notes are played, other notes can be heard to sound, just like on an acoustic piano.  (it mainly occurs when playing the upper notes). Is this authentic? I never paid any attention to this when I had a Rhodes.   The Wurly does this too, and I know that this is *definitely* authentic because my own Wurlitzer does it. I don't think it's harmonic related like it is on an acoustic piano - I think it's simply that because all the reeds are mounted on a common "frame", the other reeds are shocked into vibration by the shock wave that travels through the frame when the notes are played. 

EDIT: Actually, the Global Resonance affects BOTH of the above effects.

Greg.

Last edited by skip (05-03-2009 13:38)

Reply by Gizmao

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Re: Questions about the Rhody.

I think there is an infinitesimal small amount of sympathtic resonance -- if any -- in a hardware Rhodes. Maybe between adjacent notes, but then the uneven harmonic ratio between those is not really conducive to that.

And in absence of a soundboard, there should not be too much spill over larger interval spans. At least, that is what I remember from my brief experience with a real Rhodes.

However, the shock-induced global excitement theory (SIGET) you proposed here makes sense indeed

Seriously, it would obviously be most realistic to set both resonance sliders to zero.

Last edited by Gizmao (05-03-2009 13:55)

Reply by skip

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Re: Questions about the Rhody.

Thanks. Note that the swelling effect isn't present in the Wurly, even when G.R is increased. I'm curious to know why only the Rhody instrument does this.   (it may be that the Wurly does it too, but because the Wurly is more percussive in general, it's not as pronounced and I'm not noticing it)

To hear the swelling, increase G.R to max, depress the sustain pedal, and just play middle C, for example.   It happens even at the default G.R setting, but to a lesser extent.  (still a bit too much for my liking for general use, but I definitely want some of this effect)

Greg.

Last edited by skip (05-03-2009 21:29)

Reply by hyper.real

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Re: Questions about the Rhody.

Isn't this to do with the mode of mechanical excitation in the Fender Rhodes, i.e. effectively more stroking than striking?

More precisely, the tone-bar which is the the sound-generating element, is not receiving the transient excitation from the key-press, but is getting a steady(ish)-state energy input from the tine that has been set into vibration. At low energy inputs (no soundboard coupling here), it would take some finite time for the energy to build up in the tone-bar to its full capabilty.

In abstract, 3 ways to couple an energy input to a system:

1. Transient input -> immediate peak output, e.g. piano.

2. Steady input -> immediate peak output, e.g. organ.

3. Steady input -> non-instantanous peak output, e.g. Fender Rhodes.

From which we may conclude that the Fender Rhodes is a significant piece of culture. It also sounds cool, too.

Or, how about this:

A. Piano: many keys map to one soundboard.

B. Fender Rhodes: one key maps to one soundboard (but call it a tone-bar).

Cool stuff happening there.

Reply by skip

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Re: Questions about the Rhody.

But why would it be any different with the sustain pedal depressed?
I am simply pressing the pedal, and playing a single note, once only.
It is most definitely a lovely effect, whether or not it's authentic.

Greg.

Last edited by skip (06-03-2009 01:53)

Reply by hyper.real

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Re: Questions about the Rhody.

The mechanism had dampers in contact with the tines, which could be disengaged by the pedal, thereby effecting a sustain. Without damping, the resonant system would tend to absorb input energy until it reached an equilibrium, which took a little time, during which the sound would build in intensity.

The "rude mechanicals" can be seen here:

http://www.fenderrhodes.org/rhodes/manual/

Reply by skip

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Re: Questions about the Rhody.

Of course it had dampers, otherwise the notes would sustain forever until they decayed to silence - the mallets struck the tines, not the tone bar.

My point is this: In Pianoteq, with the sustain pedal down, the note swells more than it does when the note is played normally, with the pedal up.
The only difference with the pedal down is, of course, that all the other notes are also undamped.  As I say, the effect is strengthened when Global Resonance is increased.

Now, despite the swelling effect, I cannot hear any of the other notes (well not really - I haven't listened REALLY hard yet), when playing a lower note, such as middle C. It sounds to me like that note is just getting louder all on it's own accord. If it were the other notes "helping" it to swell, you'd expect to hear the other notes sounding a bit as well.

Other than the fact that all the other tines are undamped with the pedal down, there is no other difference for the note actually being played.

EDIT: Could it be that this swelling *is* authentic, however, the swelling should actually only occur for repeated notes? I.e, the swelling should not occur the very first time the note is played, but if the note is played multiple times in succession with the pedal down, there will be a swelling effect because the tone bar's resonance is growing a bit each time? If this is the case, then I think it means Pianoteq's model has a slight defect, because in Pianoteq, the swelling occurs even for the very first time the note is played with the pedal down.

Greg.

Last edited by skip (07-03-2009 07:36)

Reply by Philippe Guillaume

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Re: Questions about the Rhody.

Greg, the sound is different in the Rhodes when the sustain pedal is down because of the resonances of all the tuning forks which can vibrate freely as the dampers are not in contact anymore with the tines. As you mentioned, the energy is transmitted mechanically through the whole structure (frame, rails,…). A similar resonance occurs in the Wurlitzer (and of course in the pianos also), you can hear it if you push the Global Resonance control to the right, particularly in the high notes. You are right that it is a bit different in the Rhodes than in the Wurlitzer, but the tone sources are not the same neither. For example they have more mass in the Rhodes because of the tone bars. Note that all these resonances occur also without sustain (and are controlled by the same Global Resonance slider), but they are much shorter because of the dampers. I didn't catch the difference you made between points 1 and 2, for me it's the same thing: it comes from the resonances produced by the rest of the instrument. Note that you can suppress this effect by pushing the slider to the left.

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Reply by skip

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Re: Questions about the Rhody.

Thanks Guillaume.

To me, something doesn't sound quite right though.
For my test case (middle C), the resonance sounds like it's impossible on the real instrument, even on the default setting of G.R.  Almost all the sound seems to eminate from the middle C note (i.e it's own tine/tuning bar), and almost none from the other notes. Yet, it swells as if the volume control is being increased just after the note is played.
I still don't understand how this could happen on the real instrument. (and I'm not insisting that it doesn't happen - I just don't understand yet how it could happen)

In any case, I'm definitely *not* going to dial it out completely - I'll just reduce G.R a bit for my tastes for general playing.

Greg.

Reply by Philippe Guillaume

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Re: Questions about the Rhody.

Greg, that’s a real question: where does the sound comes  from? On the Rhodes (here a Suitcase MARK1 73), it comes either out from the 4 loudspeakers, either via the line out (which is 99% mono), so how can one hear that the resonances come from middle C or another place? The fact is that these resonances are produced by the other tone sources in the real world, or their simulation in the model. Concerning the sound location in the model, one can play with it by placing virtual mics around the instrument: the Rhody offers things that are not possible in the real world...

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