Perantucci mpc taper?

[ghmerrill]

Just curious.

I've been experimenting with some mouthpieces (in part switching from Helleberg style to German for the sound). I've got this PT-89 that I really like for the sound it gives me, especially below the staff. But in the staff the second valve plays noticeably flat with it, and it's a bit of a pain to correct for this (I know the second valve is a bit flat in general on this particular horn -- which is unfortunately odd because it has such a LONG slide to correct it if it were just sharp -- but there's not much to do about that).

I now have on trial a bunch of other mouthpieces that are shallower and I'm just playing around with. One is a PT-65, and the others are Miraphones. What I noticed immediately is that the Miraphone mouthpieces seat more deeply into the receiver than the Perantucci's do -- by maybe as much as 3/8" (or a bit less). I then checked this against a couple of others I have (Schilke Helleberg, Conn 120S, and Kellyberg), and the Perantuccis definitely don't seat as fully in the receiver as the others do (while all the others seem to seat to at least close to the same depth). Not surprisingly, the Miraphone (and other) mouthpieces have the horn playing in tune a bit better. The one that's working best so far in terms of overall intonation and quality of tone across the range is the Miraphone Rose Solo. Not quite as nice in the real low range as the PT-89, but acceptable.

What's the deal with this? Why are the Perantucci mouthpieces so different in terms of the taper?

[imperialbari]

Perantucci used to come in 4 shank dimensions, but apparently now their standard version is the European shank with the others as special order options.

The other brands you mention appear having the slightly narrower American shanks.

Klaus

[ghmerrill]

Clearly this whole globalization thing is getting out of hand.

So I have a Czech tuba that wants a mouthpiece with an American shank that I get from a German tuba manufacturer, while another German manufacturer provides mouthpieces with a European shank.

I knew when I saw all the skateboarders in Barfüsser Platz in Basel some years ago that things would not be going well.

[imperialbari]

Globalization takes many forms. The Babylonics of tuba shanks maybe is a newer variant than this one:

[ghmerrill]

An import inside micrometer in the appropriate gauge range, and an import dial micrometer are not very expensive.

I don't currently own an inside micrometer. And I'm a sucker for measuring tools. But I'm not sure what that would tell me other than what I already know, which is that the Perantucci mouthpieces don't seem to be such a good fit for this horn (not in the sense that they don't "fit", but in the sense that they make the tuning a bit wonky).

I have thought briefly about the possibility of replacing the mouthpipe. But the consequence of that would appear to be that a bunch of other mouthpieces wouldn't fit, unless I could find an adapter (or make one, which I currently don't have the machine tools to do, and I don't think I can use this to justify buying a nice metal lathe in addition to the micrometer -- unfortunately).

[Dan Schultz]

An import inside micrometer in the appropriate gauge range, and an import dial micrometer are not very expensive.

I don't currently own an inside micrometer. ....

You could have your repairman order you a generic tuba mouthpiece receiver from Allied... part number A221. Probably about $15 unless they have it mailed my itself. Carry it in your pocket to check to see if the mouthpieces you consider are 'regular American shank'. If so... mouthpiece shanks will fit into the receiver to within 1/16" (or so) of the step inside.

[iiipopes]

As per Matt Walters' article, "American Standard" shank tip diameter is nominally .520. "Modern European" shank tip diameter is nominally .530. The PT mouthpieces I have had were about the latter. It's not the taper, per se, as the starting tip diameter. The larger the starting tip diameter, the lesser amount of shank that will insert into the receiver. Here's a link to a one posting of Matt's article:
viewtopic.php?t=10390" target="_blank" target="_blank

[ghmerrill]

Hmmmmm.......

I get close to .540 on two dial calipers -- a cheap plastic one and a reasonably good one. As closely as I can measure the tip with the good caliper, I get at least .538.

So does this mean I could sand down the shank (with some care obviously, and high quality abrasive paper) and get this thing to fit decently?

I don't have a lathe to spin it in, but with some old-fashioned hand effort, surely this could be done? I presume that taking 0.020 off the shank diameter would not leave the shank too thin.

Comments?

[ghmerrill]

In the interests of science ...

Outside tip diameter (measured with same caliper) of other mouthpieces I have:

Schilke Helleberg: .527
Miraphone Rose Solo: .526
Conn Hellebert: .526
Kellyberg: .524

[Dan Schultz]

Hmmmmm.......

I get close to .540 on two dial calipers -- a cheap plastic one and a reasonably good one. As closely as I can measure the tip with the good caliper, I get at least .538.

So does this mean I could sand down the shank (with some care obviously, and high quality abrasive paper) and get this thing to fit decently?

I don't have a lathe to spin it in, but with some old-fashioned hand effort, surely this could be done? I presume that taking 0.020 off the shank diameter would not leave the shank too thin.

Comments?

Forget trying to change the size of the shank without a precision lathe and a good setup. You might get the MP to fit to the depth you want but I'll pretty much guarantee that you'll mess up the taper.

[ghmerrill]

Geez, then it's a few thousand for the lathe (and I might as well get the lathe/mill combo). And I don't actually have anywhere to put it now. So that would require building a metalworking shop and running power to it.

Plus, I'm pretty sure my wife would notice if I stopped working on the project list I have and threw up a metalworking shop. I don't think I can get away with claiming it's just an addition to the barn or is the wood storage shed I've been planning on.

I'll need to wait for the next round of small business stimulus money for this.

[Kevin Hendrick]

Geez, then it's a few thousand for the lathe (and I might as well get the lathe/mill combo). And I don't actually have anywhere to put it now. So that would require building a metalworking shop and running power to it.

Plus, I'm pretty sure my wife would notice if I stopped working on the project list I have and threw up a metalworking shop. I don't think I can get away with claiming it's just an addition to the barn or is the wood storage shed I've been planning on.

I'll need to wait for the next round of small business stimulus money for this.

You might want to do a Yellow Pages search for machine shops in your area -- I just ran one for your entire state and it came back with 1189 listings, so I'd bet there's at least one close to you. It might be worth checking with one or more of them to see how much they'd charge to turn that taper down to match one of your other mouthpieces that fits properly (could get both PTs done while they're set up for it -- might cost less than having them done separately). They'd probably be glad for the work, and (I would hope) you'd be out a whole lot fewer bucks.

[eupher61]

A good shop should be able to measure the shank, the receiver, and make the two match properly. It isn't that difficult, but it's tedious. I have an (old number) PT9 that's been shaved down, and it's made a huge difference. At least 1/4" difference in insertion, if not closer to 3/8". The few pitch issues I had with the horn went away.

[ghmerrill]

I thought of taking it to a shop and having this done, but it gets to be a matter of tradeoffs at that point. There's the cost of that work on the mouthpiece, and then the issue about having it replated, and the time and cost in that. Compare this to the cost of just replacing it with a different mouthpiece. While I really like the characteristics of this mouthpiece, I'm sure I could find another (probably a Miraphone) that I would be equally happy with.

I don't have another PT at this time and was only trying one out (along with three Miraphone mouthpieces). As a result of that trial I've discovered that the Rose Solo is very good for me in this horn -- giving very nice tone and control across the range, a bit more facility at the top, and adequate facility at the bottom. Not quite as "big" a sound as with the PT-89, but equally attractive in its own way, and a bit easier to control. So I think that will become my primary choice.

Given all that, I think I'll just retire the PT-89 to my mouthpiece stable in the event I ever get a tuba that fits it. Or maybe sell it some time in the future. I also thought briefly of getting the receiver replaced to fit the mouthpiece, but that seems to be going even further in the direction of the tail wagging the dog.

[Doug Elliott]

This is why I make screw-shanks for tuba mouthpieces.

PT mouthpieces are (or at least were previously) .540 at the end, and that's what I have always called "European."

Mirafones and some others are closer to .530, and I call that "M" for Mirafone or Medium, which is between American and European. Older Mirafones are about .040" taper per inch (which I think may be a metric taper) instead of the usual standard .050 per inch.

[GC]

There are plenty of people out there who can turn down mouthpieces or reshank them for a sometimes reasonable fee.

Then again, if you have a Euro shank with a really big backbore, turning it down can take off more length than is practical. I had that problem when I wanted a Warburton 28D cut down; there would have been little of the shank left. That leaves completely reshanking as your only option.

[iiipopes]

Kanstul will redo tapers. They did for a cornet mouthpiece for my son. He sounded really good on an antique Blessing, but the taper was too small diameter and too straight to seat properly in a now-standard Bach-style receiver. They mill down the mouthpiece to a cylinder, sleeve it, soldering the sleeve, then re-mill the sleeve to the desired taper and tip diameter. As I remember, it cost me @$50, including the resilvering. If you have a very thick-walled mouthpiece shank, it might only need the taper milling without getting the tip too thin, since we're only talking about .010 here, or .005 per side.

[ghmerrill]

After spending a few days experimenting with several other mouthpieces and wringing my hands, I have decided to send this to Kanstul for the modification. I believe that VERY little will need to be taken off, and doing this will almost certainly cost less (and be less hassle) than trying to have it done locally (not to mention they will plate the result). I really like this mouthpiece for the low to mid range, and I'm back to the point of using my Schilke Helleberg for a somewhat brighter sound in the mid/high range. I plan to use the PT-89 for community band stuff and probably the Schilke for any quintet or smaller ensemble stuff I might stumble into (and for my own isolated solo amusement). Kanstul wants a mouthpiece for comparison and as a "target" to shoot at, so I will send them my Conn Helleberg for that purpose.

[tbn.al]

If Kanstul will do it for $50 it's a deal! I built a fixture to hold my Bach 30E while I turned it in a drill press to cut it down to a bass trombone shank. Threaded rod, large fender washer inside the cup(edges covered with rubber tubing), small washer inside the backbore and tightened with nuts at both ends. I also cut the legnth and then had to re-taper the backbore. Turned out great, but Kanstul sounds like a better option.

[ghmerrill]

I toyed briefly with the idea with of a similar approach involving the drill press, but the set-up and resulting precision deterred me. However, I might try that with a plastic Kelly mouthpiece I'm trying to get to fit my euph better.