joshnat
148 posts
Jul 06, 2011
10:54 AM
|
I got my UST in the mail from Mike Fugazzi a couple of weeks ago and finally had a chance to try it. First, on a Schilling el-cheapo harp that leaked like the Titanic: the harp became playable but not great. Second, on a SP20 in D that needed gapping anyway. Wow, what a difference! The harp is super responsive and plays beautifully with the slightest breath. I used the PDF instructions that Mike has posted, plus the Kinya Pollard article mentioned in the past. All of my previous embossing/sizing experiments had been complete disasters, with unplayable harps as a result. I was more patient and gentle with the brass this time.
A question for those of you who do this routinely: I read somewhere that after embossing the harp should be re-tuned. I'm sensing that the SP20 I did is a bit sharp, but I haven't played it into a tuner yet. Octaves are not beating. I guess I'm wondering why embossing would cause the tuning to change? The mass of the reed is still the same, just the air pressure is different, right?
----------
|
jonlaing
279 posts
Jul 06, 2011
11:01 AM
|
Embossing also changes the tone, and makes it brighter, which could make sound sharper, without it actually being brighter. I couldn't imagine why embossing would change the pitch, but hey I'm not a customizer, so what do I know.
|
jim
886 posts
Jul 06, 2011
11:20 AM
|
Embossing changes the response (i.e. air loss), that's it. The rest is placebo.
Your sp20 has detuned by itself (that's what brass constantly does, after all). PLUS. You now play octaves with a different breath force (you don't have to spend so much air) - so beating has changed.
----------
Free Harp Learning Center
|
jim
887 posts
Jul 06, 2011
11:26 AM
|
by the way... here are several macro shots of the reed slot after embossing using UST (reed removed to see the actual traces left).
UST is a great tool and you can see that even in the overall accuracy of the work done with it.
----------
Free Harp Learning Center
|
chromaticblues
908 posts
Jul 07, 2011
8:18 AM
|
@joshnat You can't emboss without scrapping up the reeds a little. Also are you sure it was in tune before you started? Embossing doesn't change the tune of the reed. Embossing does change the timbre of the notes being played and yes it will sound brighter due to less air loss, but it doesn't change the reed in any way.
Its kind of a rule of thumb to tune the harp last after doing work on it because you are bound to scrap them up a little bit. If your curious you could tune one before you work on it and then check the tuning after. I have never done this so I don't know what you'll find. My guees is you'll be tuning it twice.
|
joshnat
149 posts
Jul 07, 2011
8:58 AM
|
Thanks folks! I guess it's the brightness that threw me off. The SP20 sounds a bit more like a MB now, which I don't consider a bad thing.
----------
|
sergiojl
9 posts
Jul 07, 2011
9:42 AM
|
I thought that the first reason to buy Sjoeberg's ust tool is that it doesn't hurt the reeds.
And if the reeds are untouched, no retuned is necessary, isn't it?
|
jim
890 posts
Jul 07, 2011
9:46 AM
|
look at the pictures. It does not touch the reeds.
----------
Free Harp Learning Center
|
sergiojl
10 posts
Jul 07, 2011
10:00 AM
|
Jim; Did you use the drop mineral oil method or you went beyond those limits?
|
jim
891 posts
Jul 07, 2011
10:20 AM
|
I use my ears to determine when to stop. At a certain technique level, you feel when is just enough.
As for improving the gliding, I touch the chisel of the UST with my fingers from time to time - this serves as "oiling" and it glides better.
----------
Free Harp Learning Center
|
HarpNinja
1499 posts
Jul 07, 2011
10:57 AM
|
If you use the UST to emboss from the rivet down as far as you are comfortable with the shim and then press the reed down into the slot to do the rest, you won't have to worry about touching the reed.
I think the "tone" difference comes just as much from the gapping as embossing. Neither create a brighter tone as much as chamfering or other techniques that change the width of the reed.
----------
Mike
Quicksilver Custom Harmonicas
|
MrVerylongusername
1746 posts
Jul 07, 2011
11:09 AM
|
Tone=harmonic content
harmonics are the result of the reed vibration. Anything that alters that vibration: the points at which the reed flexes, the airflow and damping forces on the reed, all will, in theory, change the harmonic content of the sound.
Whether those changes are perceptible to the listener and player obviously depends on the circumstances. I wouldn't call it placebo though.
|
HarpNinja
1502 posts
Jul 07, 2011
11:12 AM
|
I won't argue that it is placebo, but I would argue the difference, especially as it related to cover plates and other mods, is much less than often described.
However, I know some people intentionally go to the extreme with embossing to intentionally alter the fundamental sound. That has just as much to do with the reed slot shape then narrowing the tolerances, etc.
With any of this stuff, you just have to experiment to find a balance of what you want and don't want. Personally, I like a GM to sound like a GM, or a MB to sound like a MB, etc.
----------
Mike
Quicksilver Custom Harmonicas
|
