I just got two Stowasser mpcs that I managed to snag off eBay. So now I have three Stowassers and the modern Ioan Scaunas mpc. The original Stowassers are like old sax mpcs: very low baffle, big chamber and very closed tip. Having three, I have made them all different, and in the process I noted some interesting things.
First, of course, a closed tip requires a harder reed. These mpcs all started with a tip opening of about .040", requiring a clarinet reed of strength 4-4.5 to play at all in the upper register. I have two opened up now to about .055", and I left one at around .045". The first two play with reeds of strength 2.5, more or less, and the latter takes a 3-3.5. When the reed strengths match the mpcs, I find very little real difference in response overall between closed and open tip. The open tips accept a bit more embouchure adjustment; the closed mpc wants more finesse, but I can do pretty much everything with both types, although the closed tip strikes me as being a bit more "stodgy", though not unpleasantly so.
Of the two more open tips, I have given them quite different facing curves. On mpc 1, the break comes higher up the rails, and is more exponential. On #2, it starts further back and is more linear. This is interesting. #1 feels more modern, and has a response I am more comfortable with: it feels more "open", and has better response in the higher second register.
#2, on the other hand, has excellent and easy voicing of the lower register, and care is needed to get the upper 2nd to speak well, as it tends to choke.
Thinking about it, this seems logical: more of the reed is involved in vibration in the latter: the tip then does not have to travel as far to close the tip, since the scrape of the reed has already bent and brought the tip closer to the tip rail. When the break is higher, as in the former, the scrape of the reed is not so much in play: the tip has to do all the bending.
With a soft reed, I found it near impossible to get anything above 2nd register A. George, it was very much like the recording you sent me of your own efforts to get up high. So I would suggest that perhaps it would make sense to check your facing curve, and turn up the tip a little more: like the last one centimeter or so to the tip rail. This may improve your high-end response without making blowing too hard.
Of course, response is a function of the scrape of the reed and how it matches the curve of the rails as well. If you take off some cane at the sides of the heart, and put that on a shorter break mpc, you can improve the low response, and a reed with thinner tip compared to thicker scrape, will help to improve the highs on a more linear, longer rail curve.
Finally, all three mpcs had an abrupt narrowing of the mpc at the throat to the diameter of the body bore. I found that opening that transition: making it more of a funnel; really opened up the sound of the instrument. With the original configuration, the horn feels very reluctant to sing: the sound is choked somehow and dynamics limited. Nice for soft playing, which is why I left one mpc alone, but for projection and dynamics, as well as a more open feeling, I found that opening up the throat was invaluable. I did not widen the back bore much: just a bit for the first 3-4mm after the chamber, but I did rout out all the wood that made a wall between the chamber and the throat. If you get the feeling that your horn is swallowing its sound, this is an area you might explore.
Finally, I want to pass on a tip about toothmarks. Wooden mpcs get grooved very easily by teeth on the top. My first mpc has tooth marks almost through the tip--at least 3mm deep. One of the new ones also had a groove about 2mm deep. I have found an elegant way to repair these: with cyanoacrylate glue. First I fill the groove with three or four applications of liquid (not gel-type) superglue. Then I spread three of four coats on the entire upper surface, and finally sand smooth and buff. This forms a hard, clear coat, which is much more resistant to tooth wear than the wood. If and when it is worn through, it is enough to repeat the process. Here is a before/after pic of one:
First, of course, a closed tip requires a harder reed. These mpcs all started with a tip opening of about .040", requiring a clarinet reed of strength 4-4.5 to play at all in the upper register. I have two opened up now to about .055", and I left one at around .045". The first two play with reeds of strength 2.5, more or less, and the latter takes a 3-3.5. When the reed strengths match the mpcs, I find very little real difference in response overall between closed and open tip. The open tips accept a bit more embouchure adjustment; the closed mpc wants more finesse, but I can do pretty much everything with both types, although the closed tip strikes me as being a bit more "stodgy", though not unpleasantly so.
Of the two more open tips, I have given them quite different facing curves. On mpc 1, the break comes higher up the rails, and is more exponential. On #2, it starts further back and is more linear. This is interesting. #1 feels more modern, and has a response I am more comfortable with: it feels more "open", and has better response in the higher second register.
#2, on the other hand, has excellent and easy voicing of the lower register, and care is needed to get the upper 2nd to speak well, as it tends to choke.
Thinking about it, this seems logical: more of the reed is involved in vibration in the latter: the tip then does not have to travel as far to close the tip, since the scrape of the reed has already bent and brought the tip closer to the tip rail. When the break is higher, as in the former, the scrape of the reed is not so much in play: the tip has to do all the bending.
With a soft reed, I found it near impossible to get anything above 2nd register A. George, it was very much like the recording you sent me of your own efforts to get up high. So I would suggest that perhaps it would make sense to check your facing curve, and turn up the tip a little more: like the last one centimeter or so to the tip rail. This may improve your high-end response without making blowing too hard.
Of course, response is a function of the scrape of the reed and how it matches the curve of the rails as well. If you take off some cane at the sides of the heart, and put that on a shorter break mpc, you can improve the low response, and a reed with thinner tip compared to thicker scrape, will help to improve the highs on a more linear, longer rail curve.
Finally, all three mpcs had an abrupt narrowing of the mpc at the throat to the diameter of the body bore. I found that opening that transition: making it more of a funnel; really opened up the sound of the instrument. With the original configuration, the horn feels very reluctant to sing: the sound is choked somehow and dynamics limited. Nice for soft playing, which is why I left one mpc alone, but for projection and dynamics, as well as a more open feeling, I found that opening up the throat was invaluable. I did not widen the back bore much: just a bit for the first 3-4mm after the chamber, but I did rout out all the wood that made a wall between the chamber and the throat. If you get the feeling that your horn is swallowing its sound, this is an area you might explore.
Finally, I want to pass on a tip about toothmarks. Wooden mpcs get grooved very easily by teeth on the top. My first mpc has tooth marks almost through the tip--at least 3mm deep. One of the new ones also had a groove about 2mm deep. I have found an elegant way to repair these: with cyanoacrylate glue. First I fill the groove with three or four applications of liquid (not gel-type) superglue. Then I spread three of four coats on the entire upper surface, and finally sand smooth and buff. This forms a hard, clear coat, which is much more resistant to tooth wear than the wood. If and when it is worn through, it is enough to repeat the process. Here is a before/after pic of one:
