• If you haven't done so already, please add a location to your profile. This helps when people are trying to assist you, suggest resources, etc. Thanks

Replacing all reeds in reed bank

Status
Not open for further replies.
oldbayan said:
I have done many reed transplants between accordions, also complete reed replacements with new sets, and every time there were adjustments required! Do not expect anything to be "straightforward".

...

Lastly, be ready to spend a couple of hours fine-tuning the reeds in their new instrument! Tuning reeds is very unforgiving... you need to be very careful. But at the end, it's great fun to give a squeezebox a new life.

Tuning is indeed always quite a bit of work, certainly after a transplant because the accordion body and the reed blocks have significant influence on the tuning.  A reed that's perfectly in tune can easily shift 5 cents or even more after transplanting it to a different accordion. Even within the same box: if you for instance take an A (440) from a piccolo reed block (thus that's the lower A) and put it in place of the A on the M reed in cassotto it will go down at least a few cents and be clearly out of tune... Accordion factories use "pre tuners" who prepare the tuning of reeds before they go in an accordion. They use a table of deviations so they tune reeds with a predetermined deviation that will be mostly compensated by placing the reeds on the block in the right position. Once inside the accordion the "final tuner" only needs to make small corrections and can work faster.
 
debra said:
Tuning is indeed always quite a bit of work, certainly after a transplant because the accordion body and the reed blocks have significant influence on the tuning. (...)

Indeed. The most disconcerting (pun intended) is when the two reeds on the same plate, for the same note, need to be fine-tuned differently!

Also, we need to keep the octaves consistent. Quite a task.
 
My guess is that you'll spend less time refurbishing (cleaning/revalving) the original reeds than you would if you go down the replacement route. The problem will be..to avoid altering the pitch and voicing during cleaning (use a gentle abrasive block..like a Peco Rail cleaner... and brass scraper). If you can achieve that most of them will go back in and sound not too bad, with minimal tuning, though you'll probably have to check/tweak the voicing, to get them to 'speak' when a moderate amount of air is pushed through.
Just make sure you put them back in the same spot with the same inside/outside reed orientation.
 
oldbayan said:
I have done many reed transplants between accordions, also complete reed replacements with new sets, and every time there were adjustments required! Do not expect anything to be "straightforward".

In my experience the reed plates were never exactly the same size as the originals. Worst case is when the reed plates are longer than the originals, and you need to "extend" the reed block. In the opposite case, there might be space around the reed plates that need to be filled with small pieces of wood so the reed plates sit correctly in place.

Incidentally, I just transplanted last weekend the "M" reeds from an old Hohner Verdi to a Soviet bayan box, recovering also some reeds from the bass side because the treble side has 58 notes. Funnily enough, most of the Hohner T reed plates were smaller than the originals, which look like East-German reed plates. But the low notes on the Hohner sound much better than the bigger, longer reeds they replaced. They are also much more responsive.

Bottom line, it's a project, you will need to take your time. If you use wax you will also need the proper supplies and equipment to seal the reed plates. Spare valves are also handy.

Lastly, be ready to spend a couple of hours fine-tuning the reeds in their new instrument! Tuning reeds is very unforgiving... you need to be very careful. But at the end, it's great fun to give a squeezebox a new life.

Hi, 
 Yes, you are right! And I found that once I've removed all the reeds from the reed block that the ones I wanted to replace them with were in fact too long. So, I've stuck with what was there and cleaned them up and revalved them all.

I've just relaxed them back into the reed block and most of them are sounding great apart from a few in the middle that seem quieter for some reason. It's almost as if they're not getting enough air or something. Could this be to do with the valves I wonder??

These thing do take a long time and this project has taken me way longer than I first anticipated. But I have a lot of space time just now so don't mind.
 
Neoscan said:
Hi, 
 Yes, you are right! And I found that once I've removed all the reeds from the reed block that the ones I wanted to replace them with were in fact too long. So, I've stuck with what was there and cleaned them up and revalved them all.

I've just relaxed them back into the reed block and most of them are sounding great apart from a few in the middle that seem quieter for some reason. It's almost as if they're not getting enough air or something. Could this be to do with the valves I wonder??
...
When a reed is sounding weak there are a few possibilities. A valve that is giving too much resistance will cause a reed to sound weaker and also lower in frequency. But voicing is also important: when the reed sits too high it may not respond well at low pressure but will sound stronger than when it sits low (and responds well at low pressure and chokes at high pressure). When the reed plate does not make good contact with the reed block it will not transfer sound in the same way as reeds that do sit well on the block. When the resonance chamber in the block does not resonate at the frequency of the reed it will not amplify the sound properly... In the end you should be able to make all reeds sound ok, but even then when you measure the sound volume at the same air (bellows) pressure you will see that the volume is still not all that equal.
 
Try turning the reed plate 180 degrees, with the end of the blade pointing toward the base of the reed block. Also flipping the plate over.
 
oldbayan said:
Try turning the reed plate 180 degrees, with the end of the blade pointing toward the base of the reed block. Also flipping the plate over.

Ah, now, that's something I would never have thought to do!
 
Status
Not open for further replies.
Back
Top