Comparison of volume between 20 key and 30 key anglo

[Rod Pearce]

I have both a 20 key anglo (Campbells of Glasgow) and 30 key anglo (late Lachenal), both of which I have restored to a playable standard in the last 12 months, i that order.

 

I am noticing that the 30 key is appreciably quieter than the 20 key. Is this to be expected, or should I continue to work on the 30 key to increase its volume?

 

Both have new pads and valves, but the 30 key needed new springs and lever arms and bellows due to damp and rust. I have also noticed that the 20 key is also much 'tighter', but I cannot locate any air loss in the 30 key. Perhaps it is the spring tension, or the newer pads?

 

Any thoughts?

 

Best regards

Rod

 

[Geoff Wooff]

There are  many things that  can influence the  output  volume of a concertina.  The  20key  being 'tighter'  would  suggest  you should  be  getting a better  attack  when  a button is  pressed  with more  compression  available.  However, if  everything  else  is  equal, and  it  can  never  really  be,  then  the  extra  reeds  of  the 30 key  instrument  will  have  a slight  deadening  effect  on the reed pans.  

 

More likely   the  height  that the  pads lift,  and  how  soft  they are, how well the reedpans  fit  into  the  bellows  and  how  flat  the  wood  of  the  reedpans  and padboards are  and  the well fitting  of the  gaskets .  Even  the  wood  of  these  pieces  can  make  a large  difference.

 

What  matters ?  Everything !

[Stephen Chambers]

Apart from everything that Geoff Wooff has already mentioned, and to compare like with like, I always find that there's more of a "honk" off the reeds in a 20-key Lachenal than there is off a 30-key one of the same model. I'd attribute the difference to the chambering of the reedpans, which is parallel in a 20-key Lachenal (as is also the case with a Jones 20-key, or a Jeffries/Crabb), but radial (and sweeter) in a Lachenal 30-key.

[Rod Pearce]

Geoff, Stephen

 

Thank you for your responses.

 

I gather from what you say that although I should expect differences, what I am hearing from the 30-key is weaker than it should be. As all the new components are from the same source, I will continue down the path of trying to improve fit of the reed pans and gaskets to see if it will retain more air.  I am also a little suspicious of some of the reeds, given the state the woodwork was in when I started. Perhaps I am expecting too much from what was effectively a wreck, and should be happy that it plays again.

 

I will continue doing small changes over time to see what improvement can be achieved.

 

Thanks again.