Sonola low reeds slow to sound

[Rogerthomas]

Hi,

I have a Sonola PA to look at. It is a bit of a heavy beast. The low reeds, lowest end of the RH, and the low bass reeds on the LH seem quite slow to sound. Having checked the reeds and valves, they all look fine and the wax is ok. The reeds sound alright on the tuning table and the reed blocks sit snugly in place, gasket is all nice and clean and the couplers all move smoothly in and out of place. So I can only think the pressure isn't as good as it ought to be to sound these reeds responsively, but I can't really detect an airleak that might be the cause. There is a bit of a leak around one or two Treble pallets but it's not to bad, and the bellows sink pretty slowly, so the air pressure would be acceptable...I think. So I am a bit puzzled as to the cause. I mean I assume it is a problem with air pressure - but does anyone have any other suggestions? The accordion is exceptionally heavy so moving the bellows isn't the most relaxed experience. Are big accordions like this very sensitive to very small air leaks?

 

[Glenn]

How slow is slow?
It's unusual for the RH reeds to be slow enough to be annoying but the low bass reeds in the LH can have this problem. It is a physics thing that you will need more energy to get the large reeds into a steady vibration state. The quality of the reed manufacture (tolerances) probably plays a crucial role. Also a new reed set needs to be played in over a number of months

 

[JIM D.]

Your problem is not unique and occurs on many accordions with age.

On some models and makes bassoon reeds (closed to the chin) whether machine made or hand made will tend to choke with excessive pressure.

And then in your case there is the opposite, as in your case of not responding with low pressure. I'm not sure of your length of experience of reed tuning, but you should be aware that how a reed sounds and responds on a tuning table,and how it sounds and responds installed inside the accordion will differ in many cases (tone and response). Your problem suggests that the valves (leathers) on your low octave bassoon reeds are to heavy and or hardened with age and are not responding (closing properly). Replacing the old leathers with new supple leathers (and boosters if required) should solve your problem. :tup:

 

[Rogerthomas]

Hi,
Yes, maybe it's stiff valves after all.

 

[debra]

Adjusting the opening between reed and reed plate is always a compromise: when the gap is very small the note will start playing with low pressure but will choke with high pressure and when the gap is large the note will be slow to start, not playing at all with low pressure but never choking with high pressure. This is most difficult to get right for the lowest notes. But getting the notes to play immediately with low pressure and still not choke with high pressure applied suddenly simply is impossible.

 

[JIM D.]

I respect the last post but, I must agree to disagree, a quality hand made bassoon reed in a quality made box will always perform with all pressures applied. None of the higher quality Excelsior, Sano, Titano, Etc. Etc. well made pro boxes had lower bassoon reeds when new never choked. I get a decent profit for my repairs, rebuilding, and refurbishing.The Serious Pros and accordion lovers that can afford and wish to hire me to rebuild a quality box both mechanically and cosmetically as new,know that their treasured boxs I rebuild and leave my shop will have bassoon reeds that will not choke.
As always mediocre makes will always have this problem - as sadly you get what you pay for.
Accordionists with a quality boxs never had, and still dont have a problem playing in the lower register ---
With the bassoon set !!

 

[acordiansam]

Depending on what model sonola you have the basson reeds and sound were what the box was known for. What model do you have?

 

[Zevy]

<FONT font=Garamond><SIZE size=130>I agree that its probably the leathers.

 

[debra]

Sure it is quite possible to adjust bassoon reeds so they never choke. When I received my Pigini basson accordion (the three reed C39 which actually has 40 notes, not 39) none of the reeds could be made to choke. But the large lowest notes were very slow to start (using the single lowest reed only). The reeds needed to be adjusted a bit so that they would start faster with low pressure. This meant that with quick high pressure (trying sforzando) you have to raise the pressure a bit more slowly than desired otherwise the note will choke. It is impossible to adjust large reeds so they start very quickly at low pressure and never choke at quick application of high pressure. These are the best a-mano reeds. We simply cannot change the physics of accordion reeds... I love my Pigini basson and do play it with the care needed to avoid choking. Without the adjustments the lowest notes on single reed would need up to a whole second to start. That makes playing very hard.

 

[acordiansam]

I have a sonola bass only box. No left hand buttons only right hand key board. I have no problem playing in time with others. If there is a 1 sec delay there's something wrong. Sum of the low reeds are 3" long or more? Long time since I had it open. still no delay of a second.

 

[JIM D.]

Your Sonola Bass accordion has Helicon reeds in the low register and they will sound with any pressure applied. The rest of the bass reeds are larger than normal and will also sound with little pressure. :tup:

 

[acordiansam]

Helicon. Now I'll have to open it back up and take a closer look.
Thanks Jim

 

[debra]

Low reeds are slower to start when they are used alone. Also, if a note is played again within a few seconds it will start faster.
Almost all accordions and also basson accordions have the low notes played on a register that is at least LM. The middle (higher) reed sets vibration in motion that helps the lower reed to start. On for instance a Hohner Morino VI the baritone bass was set up in such a way that in the lowest octave it always used LM even when the register selected was only L. The M reeds were needed to make the L reeds start faster. (Note that on the Hohner Gola this was not the case: the L register was L only right down to the lowest note.)
The Pigini P39 and C39 are the only basson accordions that i know (from the western world) where you have switches and can play with the L reed only. (These instruments are LMH and you can play L only, LM, LH and LMH.) There is no problem with the lowest notes starting slowly when the LM register is used. It is only with the L register. In one of the orchestras I play in we sometimes play extremely softly with the lowest notes.
A reasonable (but not nearly extreme) case of what I mean can be heard in http://wwwis.win.tue.nl/~debra/rel-elst/3-ich-bin.mp3 with very soft very low notes.

 

[JIM D.]

Hi debra: I must mention that comparing German made Hohner reeds and Italian hand made reeds, is really like comparing apples and oranges. (with the exception of Hohner Morino models made in Italy) Accordions with German reeds will have valves of vertilli (plastic) that will remain closed, seal rapidly and give a good air response. If equipped with leather valves they will respond slower. A quality Italian hand made reed such as Binci or Salpa a mano types or the top of the line bombata types will perform perfectly with plastic or leather valves. Hohner did sell some bass accordions with Itailian made reeds for orchestral work
--

 

[TomBR]

Low reeds are slower to start when they are used alone.

Thanks debra, Id assumed that was true so Im glad to have it confirmed.
I guess it also makes it important to adjust the gap on the low reeds when they have the vibration of the higher set, unless it is an accordion that uses the low set alone.
Tom

 

[debra]

Here is a basson solo performance (by me):
but it is not a prime illustration of the lowest reeds as in this cello solo (played on the basson, really, its not a cello youre hearing) Im only going down to As (Ab) while the instrument goes down to the C below that.
I can tell you that when notes respond slowly it is almost always due to the reed opening being too large and not due to the plastic or leather valve not opening quickly enough. Even with a fully open valve when you apply low pressure a reed that is too far open will just let air through without starting to vibrate until its quite a bit of air going through and until enough time has passed. I have worked with (and on) several basson accordions and normal accordions with very deep bass notes. They all behave the same: the opening needs to be small enough for notes to respond quickly and large enough for notes never to choke.

 

[Glenn]

Here is a basson solo performance (by me):

Nice performance.

 

[BobM]

Here is a basson solo performance (by me):

Nice performance.[/quote]

Ditto, that is good!