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[Matthew B]

I defer to the audiophiles, physicists, engineers, and assorted luthiers here.  Speaking only from experience I notice that grill material exerts a significant influence on sound.  My oldest club box has a brass grill on it that rings aloud when the box is played.  It sounds great, and the tone is unmatched by other boxes I play, which variously have no grill, wooden grills, or mixtures of aluminium and celluloid.  Taking the grill off the box changes the sound.  

[rees]

Here's another effect that is sort of related.

The microphones in my one-row boxes that I use on stage are mounted directly on the treble reedblocks (Louisiana zydeco style).
If I play a left-hand chord, the amplified sound has a phase effect which "phases" as the bellows are opened and closed.
It must be something to do with the bellows chamber increasing and decreasing in volume and may also be related to the left-hand reeds moving further from and closer to the mic. 

It reminds me of the old "phase" pedals that were once popular with electric guitarists.
Sounds great for Zydeco.

[Theo]

For the sake of argument let's put the same reeds in two boxes.  One is the usual plywood covered by celluloid, wooden reed blocks.....

No need to imagine this.  Hohner Erica, plywood covered with celluloid and Pokerwork, solid wood, no celluloid have exactly the same reeds and reedblocks, but they don't sound exactly the same.

My take on this is as follows.  Stringed acoustic instruments rely on resonances from the structure of the instrument to transfer the vibration of the string into the air.  The string itself is very poor at moving air, mainly because it is so thin.  The reed in a free reed instrument is extremely well coupled to the air, and chops up the stream of air as it passes through, and this is by far the main way that vibrations of the reeds are communicated to the air.  The direction of travel of the sound waves is not affected by the direction of the airflow, if it was we would hear a difference between push and pull notes.  As the sound waves travel from the vicinity of the reed they have to pass through the structure of the instrument and can be affected in various ways depending on the materials used and how they are put together.  Mostly the affect is that there is selective absorption of some frequencies, which colours the sound.  For example metal is smoother and a reflects more sound than wood,  which goes at least part way to explaining the observable differences in sound between instruments with metal or wood grills.  The surfaces of the wood grill absorb more especially of the high frequencies, so the instrument with the wood grill typically sounds more mellow, and the one with the metal grill sounds brighter.

[C age ing]

On top of your comments Theo, how can one find out what a pure reed actually sounds like. To do this we would have to mount it in free space, presumably from sky hooks, oscillate it with a known quantity and quality of gas and then measure it. Problem: space=no air=no sound=impossible.
Another twenty-five gallons of Omega 3 and back to dozing in the armchair.
Even grumpier and less talented Old Bill.

[Steve_freereeder]

On top of your comments Theo, how can one find out what a pure reed actually sounds like. To do this we would have to mount it in free space, presumably from sky hooks, oscillate it with a known quantity and quality of gas and then measure it. Problem: space=no air=no sound=impossible.
Another twenty-five gallons of Omega 3 and back to dozing in the armchair.
Even grumpier and less talented Old Bill.

You could do it by mounting the reed plate in some sort of closed vessel fitted with inlet and outlet tubes, through which the vessel could be evacuated or filled with various gases or gas mixtures as needed. The reed tongue could be set into vibration by applying a rapidly fluctuating magnetic field tuned to the appropriate frequency of the reed. The sound generated could be picked up by a small contact microphone mounted directly on the reed plate, or else in the case of a gas-filled chamber, by a microphone suspended in the gas space.

What it would tell you, I don't know, but I'm sure there's a research project there for someone somewhere.
Me? I'll continue using my ears and playing my melodeons.
Back to my own Omega 3 now....

[finnhorse]

On top of your comments Theo, how can one find out what a pure reed actually sounds like. To do this we would have to mount it in free space, presumably from sky hooks, oscillate it with a known quantity and quality of gas and then measure it. Problem: space=no air=no sound=impossible.
Another twenty-five gallons of Omega 3 and back to dozing in the armchair.
Even grumpier and less talented Old Bill.

You could do it by mounting the reed plate in some sort of closed vessel fitted with inlet and outlet tubes, through which the vessel could be evacuated or filled with various gases or gas mixtures as needed. The reed tongue could be set into vibration by applying a rapidly fluctuating magnetic field tuned to the appropriate frequency of the reed. The sound generated could be picked up by a small contact microphone mounted directly on the reed plate, or else in the case of a gas-filled chamber, by a microphone suspended in the gas space.

What it would tell you, I don't know, but I'm sure there's a research project there for someone somewhere.
Me? I'll continue using my ears and playing my melodeons.
Back to my own Omega 3 now....

Sounds complicated, but could the Chinese be up to it?   

[ghijze mitter hacken]

A Dutch builder told me once that a MDF plate as a fondo gave the best results. I can't imagine that MDF has any vibrating qualities, so the sound produced by the reeds will only be altered when leaving the instrument. So there will be a difference in sound using a wooden or metal grill. Concertina builders sometimes baffle the inside of a metal grill to reduce the number of partials.

But, when playing my small sized one voiced organetto I can feel the left casing vibrating!

[C age ing]

A Dutch builder told me once that a MDF plate as a fondo gave the best results. I can't imagine that MDF has any vibrating qualities, so the sound produced by the reeds will only be altered when leaving the instrument. So there will be a difference in sound using a wooden or metal grill. Concertina builders sometimes baffle the inside of a metal grill to reduce the number of partials.

But, when playing my small sized one voiced organetto I can feel the left casing vibrating!

You realise you are suggesting that when you strike a piece of MDF with another piece of MDF, there is no sound whatsoever?

Ah well, back to sleep.
Even grumpier and sleepy Old Bill.

[Lester]

But, when playing my small sized one voiced organetto I can feel the left casing vibrating!

Both my Castagnari and Salterelle boxes complain if I play poor chord choices. They let you know by feeling odd in the way the case vibrates.

[Rob2Hook]

I go along with Lester's last remark.  Sitting in a session when you can barely hear the treble end, which is wedged under your right ear, a strange lack of feel comes over the box and then you realise that you're playing the bass in D to a tune in G...

[Falseknight]

I go along with Lester's last remark.  Sitting in a session when you can barely hear the treble end, which is wedged under your right ear, a strange lack of feel comes over the box and then you realise that you're playing the bass in D to a tune in G...

Why would that be a surprise if the sound from the reeds is propagating into the bellows space and interacting?

[Mike Higgins]

Base somehow indicates that which is low and underhand whereas bottom ahhhhhh

[Andy in Vermont]

  Mostly the affect is that there is selective absorption of some frequencies, which colours the sound.

Years ago I heard a lecture by the concertina-builder Wim Wakker and that was essentially what he said.  It's not that the materials are adding to the sound, but each material subtracts different overtones to different degrees.  Perhaps I'm not recalling exactly what he said, but that is how I remember it.  It made sense to me at the time.

Additionally, I would like to add that reed plates attached with nails or screws can be more firmly joined to the reedblocks, and there is also some difference in sound if no wax at all is used (in which case there is often a gasket of chamois or cork between the reed plates and the blocks.  There is also a difference in sound if the blocks are glued to the board vs. held down onto a gasket with screws at the ends.  

I vote for "action board" (referring to the other side of the board).

[ghijze mitter hacken]

Bill,

I did not suggest anything at all. I just quoted the words of a Dutch builder of melodeons who thought MDF the best material for sound boards.

[C age ing]

Bill,

I did not suggest anything at all. I just quoted the words of a Dutch builder of melodeons who thought MDF the best material for sound boards.

Sorry Young Sir, did not mean to accuse you of anything. The equally ancients on this board will tell you I like a laugh and stirring it up on subjects like this.
Used to use another name, known to Theo but too lazy now. Also feel that it is good to query items that do not sound quite kosher. Hitler always maintained that if you tell a lie, tell a big one. Sadly some 'experts' still use the technique and all politicians.
Old Bill.

[IanD]

Answer to last question. No.

Realise that this is a generally disputed topic but all through my long career in music, career in this case being the plunging downhill out of control sense, any change, however slight to any instrument, affects what is heard. Us saxophonist argue whether the instrument's body finish has any affect but as it is possible to feel the instrument body vibrating, it must colour the sound, however slight.
Play a note on your melodeon and at the same time feel around whatever other parts you can reach, somewhere there will be an excitation. That will affect the sound of the instrument and for those who cannot detect these small sympathetic vibrations, I feel sorry for your partners. *A rotten trick to play on your supposition Young Bill, but funny.*
Why else is the Aussie arm of this forum experimenting with building in different materials, because there aint no such thing as an anechoic chamber, therefore all materials used colour the tone, ask the architectural acoustic engineer.
Now back to sleep in preparation for another twenty-five gallon top up followed by another blues session on the electronic keyboard as even that is affected by the build material.
Grumpy and diminishing brained Old Bill.

We've had this debate over and over again. Nobody is saying that materials have *zero* effect, but due to the way that free-reed instruments generate and propagate the sound any effect will be *much* smaller than things like the reed shape/fitting/dressing, and shape and size of the various cavities inside the instrument.

I could guess (figures are debatable) that the influence on the sound is something like:

construction/internal cavities/resonators/grille (including internal varnishing etc)  -- 50%
reeds/reedplates  --  40%
method of attaching reeds (wax, leather, nails)  -- 5%
materials  (body, reedblocks, "soundboard") -- 5%          <== maybe 50% for a stringed instrument

If vibration conducted from the reeds into the body affected the sound it would have to be loud enough to be audible over the sound directly coupled into the air from the reed airstream; if this was the case, you'd hear a loud after-noise after closing the pallet and shutting off the airstream -- and this obviously doesn't happen.

The movement of the reed itself doesn't make any significant noise or generate any significant energy, and the "Q" of the reed (stiffness and method of mounting) also has little (not zero) effect for this reason -- the reed is driven by the air and vibrates with an almost constant amplitude, the tonal quality is affected by the shape of the reed, the fit of the reed in the frame, the way is is dressed in the frame, because all these affect the shape of the air pulses produced, which is what makes the sound.

And any instrument builder -- howerver experienced -- who says "**** sounds better" should be believed only if they can tell the sound of instrument A from instrument B (which are identical apart from the difference under investigation) *without* knowing which is which -- otherwise you can end up in the "expensive gold-plated mains cables sound better" camp, who funnily enough can only pick out the differences when they know which one they're listening to (bias due to expectation).

The extreme case of this is the "nothing can rival a Stradivarius" school; one modern violin maker claimed this was false and was loudly shouted down, so a recital was held under controlled conditions comparing one of his instruments to one of the world's top-rated Strads. The audience was made up of musicians (including top violinists who played Strads), music critics, regular concert attendees, and instrument makers.

All the groups could tell the difference, and identified Instrument A as the one they preferred the sound of i.e. the Strad.

Which was a shame, because it was the modern instrument...

Ian

P.S. Of course I'm not saying that instrument makers don't know what they're talking about -- but in all subjective fields, including musical instrument making, there are always people who genuinely believe something which turns out to be wrong when put to an impartial  test :-)

[C age ing]

IanD,
"I could guess (figures are debatable)" does impress but not convince me.
Reminds me of the Auklander who brought his crew and boat across to compete in the One or Half Ton Cup. It was the first racing yacht of that class without a deckhouse, id est level, like a racing dinghy. All the crew wore "The Mushrooms" on their tee shirts and when asked the significance, replied, "We're kept in the dark and fed bullshit.".

[IanD]

IanD,
"I could guess (figures are debatable)" does impress but not convince me.
Reminds me of the Auklander who brought his crew and boat across to compete in the One or Half Ton Cup. It was the first racing yacht of that class without a deckhouse, id est level, like a racing dinghy. All the crew wore "The Mushrooms" on their tee shirts and when asked the significance, replied, "We're kept in the dark and fed bullshit.".

I don't bullshit. If you've got any more "accurate" figures (or a better guess based on real information, not hearsay) please do enlighten us :-)

Ian

P.S. You might want to go and read up on many of the books and papers that have been published about the acoustics of musical instruments -- especially free reed ones --  first...

[Québécois]

I guess the main problem is that there aren't two pairs of ears that can hear sounds the same way!

[Andy in Vermont]

I could guess (figures are debatable) that the influence on the sound is something like:
construction/internal cavities/resonators/grille (including internal varnishing etc)  -- 50%
reeds/reedplates  --  40%
method of attaching reeds (wax, leather, nails)  -- 5%
materials  (body, reedblocks, "soundboard") -- 5%          <== maybe 50% for a stringed instrument

Do I understand this correctly, that what you are saying is that if I build a melodeon out of plastic in which the internal cavities are the same dimensions as those of a Castagnari Hascy, and the reedwork (tuning and "dressing" of reed and method of attaching to the block are identical, that there would only be a 5% difference from the sound of the Castagnari?  I'm not trying to criticize your argument; I'm just trying to see if you intended your estimation to mean this.

Years ago, I recall Rich Morse of the Button Box posting to the usenet accordion forum in response to a thread where someone asked about the possible outcome of putting high quality reeds in a cheap accordion.  Rich responded that the Button Box had some experience with this, and his estimates of influence on sound even included the effect of putting lower quality reeds in a high quality box.  If I recall correctly, he said that the higher quality reeds did not greatly improve the sound of the cheaper box, but also that the lower quality reeds did not greatly reduce the sound quality of the high-end box.

 To me, these (anecdotal yet experienced-based) data suggest that your estimate values the influence of the reeds too highly.  Nevertheless, I'm fairly certain that I'm with you in putting the reeds at 40%, but I can never tell with these things, since I'm general extremely sensitive to minor changes, so what really stands out to me might not be so important to the ears of others.  I'm not saying that my hearing is better, just that it is sensitive to the point of rendering me incapable of distinguishing which differences might be important for the majority of listeners.
-Andy