Excelsior Accordion Feature

[boxplayer4000]

Pitzelberger: Thanks for the observation. Dingo40 raised this subject a few entries back in this thread. ie. what difference the 'sound post' would make and if the difference was detectable when the device was in or out. My own feeling is that the designers would leave no stone unturned, however small the stone, to try and improve the sound. Other techniques to try and improve sound include things like varnish/lacquer and metal ties between and on top of the treble reed blocks.

 

[rhythmbox]

My Excelsior has an identical „sound post“. I occasionally forgot to put it back in place, but have not realized any difference while playing the accordion.

Many thanks for this contribution...which I think confirms my view that Excelsior, at least, consider the spring to have a valid purpose, and it's not some whimsy added by a tech at a later date...
As a matter of interest...is your Excelsior a cassotto model..? My gut feeling is that the tone chamber is at the root of this conundrum...
I understand Excelsior have been approached for their input...but I'm afraid I don't hold out a lot of hope, having dealt with Italian manufacturers on a regular basis over many years...

 

[Walker]

What a lovely little spring-loaded gizmo. I've seen them on lots of vintage Excelsiors over the years, magnificent instruments they are. As an accordionist with an interest in the construction and design of the accordion from a strictly theoretical point of view - I'll leave the dirty work to all the esteemed practical experts here. However, for what it's worth, I would suggest that the spring-loaded aspect of the device indicates that it's primary intention is to assist in providing an even tension across the reed blocks, even when there are movements or vibrations within the accordion, for example the vibrations during musical performance. I have noticed even more substantial spring-loaded devices used within the bass reed blocks of the vintage Scandalli Super VI for the same purpose of providing even tension.

I really like the thought process of @boxplayer4000, in the suggestion that the device may form an acoustic bridge to transfer vibrations from the reed block to the accordion case. However, I can't see this as being it's primary function, by the nature of springs being more of a dampener of vibrations rather than an amplifier of them. However, that said, I do believe the accordion case does play a significant role in the overall sound produced by an instrument. One just needs to compare the tone of an accordion with solid wooden construction, compared to one coated in celluloid, there is a difference in sound. Interestingly, I have heard many people comment on the classic Excelsiors having wonderful characteristics including - the way in which the player can often 'feel' the vibrations of the accordion in their body.

These thoughts are just a theory and not empirically tested. Just my 2 cents.

 

[Dingo40]

Walker,
You're right: some accordions vibrate all over when played, making them feel alive.
Some of mine would set the strings of the piano in the room "humming" in sympathy.

 

[pitzelberger]

As a matter of interest...is your Excelsior a cassotto model..?

Yes, it is an AC with cassotto.

 

[boxplayer4000]

Walker:
Thanks for your usual, informative, full entry, in a debate. You say “I’ll leave the dirty work to all the esteemed practical experts here”. The word ‘expert’ is an interesting one and I am reminded of what John Reith (first director-general of the BBC) said to his journalists and broadcasters. He cautioned them against using the word ‘expert’ because (I can’t remember his exact phrase but the thrust was) who decides what an expert is? And if the person you’ve titled ‘expert’ turns out not to be then you will have lied. I believe it takes a long time in any situation to become an ‘expert’ and helpful as it is for us amateurs to better ourselves, things like a two-week course in Italy, or elsewhere, does not produce an ‘expert’. It’s my belief that true experts don’t inhabit places like ‘accordionistsforum’, although they may do from time to time just to get the occasional laugh.

I take your observation on board that a spring might be a dampener in certain situations but in the case in question any vibrations are carried in the solid metal of the ’T’ bar. The spring serves only in pressing the the top of the ’T’ against the reed blocks. I also agree wholeheartedly that an accordion’s construction, including its outer shell has a lot do with the sound diffusion.

Age is a good excuse to reminisce so no apologies for this. While still at school I remember experimenting with our own ‘telephone’ line. This consisted of two empty tin cans and a long piece of wire (fence wire in our case). Being raised in a rural situation the material and the space was available to us. The ends of the wire were firmly fixed to the outside, bottom of the tin can which then became a diaphragm. If the wire was held as free as possible from obstructions and dampening then it functioned quite well as a ‘telephone’ when the vibrations caused by the human voice speaking into the can at one end were transferred to the other remote can diaphragm which amplified them to audible level. It was crude but illustrated perfectly the passage of sound in solid material.

 

[Walker]

Thanks @boxplayer4000, I do enjoy joining in on the conversation - though I'm usually way out of my depth . I find I am regularly in awe of the knowledge, skill and intellect of so many people here. I will however spare all of the multitudes of blushes by not naming names, and just say that compared to me there are many, many experts here.

 

[debra]

There's no room to fit it closer to the centre; by a previous repairer or not.
Observations about perfectly straight reed blocks, excess pressure/sticking slides apply to ALL accordions, cassottoed or not.

Obviously! But the trick used to apply a bit of local pressure somewhere between the ends of the reed block only works in cassotto as you can use the side of the treble case (to push) or the cassotto itself (to pull) to add pressure locally.

 

[Pipemajor]

good eye

i have noticed the mylar/whatever they are made of reedflaps
seem to pinch/catch against the leather/man-made-material main flaps
on occasion when used as half or 2/3 length boosters..

but i would have crimped the tips in the other direction,
to ensure a smooth liftoff

so i cannot imagine why these are crimped toward the flaps
unless he had the idea too, but got reversed in his head for
the logic of it

i predict they will catch a lot more often than flats and end up
being a nice try but.............

To my eyes it seems that the crimping is in the plastic "booster", not in the valves themselves.
Wouldn't this help the valves stay closed?

 

[Ventura]

the plastic is so thin, but stiff in a different way than booster springs

the squared edges of the plastic flap gives you two 90 degree sharp "points" and
they are what occasionally snag against material valves
angling them TOWARD the valve can only increase the potential for a snag,
as it aims the corners into the material

a partial length booster allows the material to bend at it's top first,
while holding the rest flat, then as pressure builds lifts the entire valve as normal,
but again the top increased angle against the sharp corners gives snag potential

as i suggested, angling the fold outward would give only a totally smooth leading edge
against the fabric, avoiding any possibility of snagging

imho

 

[tcabot]

With respect, this is something should share as soon as possible with violin makers.

With respect, this is common knowledge.

 

[Tom]

Oh those dreaded sound posts!!!! A million years ago when I was repairing lots of stuff, cutting and fitting soundposts was always the last thing on a violin. It's so hard, a real art that I never fully mastered. (One of many, if not most ). I knew proper placement and fit affected the sound, but also felt it prevented the top of the violin from slumping from the pressure of the strings on the bridge. And violin is so much harder to play than accordion.

 

[boxplayer4000]

Walker: I think you're being far too modest in your entry above. Remember what Winston Churchill said about Clement Attlee when he made references about modesty: He said: " He (Attlee) had much to be modest about." I'm sure this doesn't apply in this case at all.

Thanks to all for pitching in. The range of experience and opinion is good.
If anybody remembers the original question; it was to identify a small, metal hinged/sprung device in an Excelsior 904. My original thought was it was a sort of 'sound post' as fitted in a violin but a lot opinion here seems to favour it as a securing device.

 

[debra]

Obviously! But the trick used to apply a bit of local pressure somewhere between the ends of the reed block only works in cassotto as you can use the side of the treble case (to push) or the cassotto itself (to pull) to add pressure locally.

Well, some accordions do have a similar contraption for reed blocks outside of cassotto:

 

[boxplayer4000]

Debra: Thank you. I've seen those and I have fitted some of my own on older accordions where it was becoming difficult to get a good tight face between block and sound board. The one on the Excelsior accordion puzzled me as the spring on the T-bar arrangement was so weak it felt that it could have little effect securing the reed block. I think the Excelsior in question is c1972.

 

[debra]

Debra: Thank you. I've seen those and I have fitted some of my own on older accordions where it was becoming difficult to get a good tight face between block and sound board. The one on the Excelsior accordion puzzled me as the spring on the T-bar arrangement was so weak it felt that it could have little effect securing the reed block. I think the Excelsior in question is c1972.

Note: it's not just a "bar" between the two reed blocks. It has a long bolt that goes into a threaded hole in the soundboard in order to provide tension to the reed blocks. Many accordions have just a bar between the reed blocks which dampens vibrations in the reed blocks. Sadly the bolt is not very clearly visible in the picture.

 

[boxplayer4000]

Debra: Thanks again. I've probably not been clear but I did appreciate that in your photo the bar was not just sitting on top of the reed blocks but was held to the soundboard by the central screw/bolt. A different arrangement of course to the simple metal bars fixed to the tops of the reed blocks. I've added a few of those as well where they had not been fitted by the maker in the hope that the sound was improved.

 

[boxplayer4000]

For those who might be still interested: The Excelsior accordion at the head of this thread is believed to be 50 years old. Even although two generations have passed and Excelsior have morphed into Pigini/Excelsior I contacted them regarding the small spring loaded device in the cassotto chamber. Their opinion is that the device is there ’to keep the reed blocks in the right position’.