Chomonica 270
Hi Kinya,
I have a Honer Chomonica 270 that I bought bout 23 years ago and has been sitting in the box. Never really learned to play it.
Anyway, I started to fool with it now that David has some lessons on the chromatic and I find the harp to be leaky and takes alot more air
to get a sound.
Can this harp be adjusted like a diatonic? I can gap my own diatonics with no problems but that is abit different with the flaps and such and double reed plates?
Thanks 528hemi
Hi Joe,
I will consider sending it out to you to go over it.
Thanks 528hemi
Awesome,
Thanx Joe!
Kinya
Joe's procedure for tightening slide-mouthpiece tolerances is awesome. However, that may or may not be the problem.
By the way, Joe Spiers has a great reputation as an amazing harp tech and we're lucky to have him here.
Older Hohner 270s are often quite leaky. You can experiment with tightening the mouthpiece screws, and that may help. Tighten one screw until the slide no longer moves freely, then back off about a quarter turn. Then do the same with the other screw. That may give you an improvement in airtightness.
At the front of the harp reedplates and comb need to present a flat surface to form an airtight interface with the mouthpiece assembly. If this is not perfectly flat, you can get leakage. One way you can test this is to remove the mouthpiece assembly, and also remove the slide spring (which is held in place by an iron post that goes through the reedblock at the right side - poke this out then carefully remove the spring using needlenose pliers - with a firm gasp so it doesn't fly away to parts unknown.Then paint the front of the comb and the front edges of the reedplates with a dark colored permanent marker. Place the painted edge on a piece of medium grit sandpaper (say about 180 grit) on a perfectly flat surface and lightly sand, holding the reedblock so that you're distributing pressure evenly along the length and width of the surface you're sanding.. Low spots will retain the dark color, while the sandpaper will remove color from high spots. Ideally, you'll already have a perfectly flat front surface and all the color will come off at once. To seal any tiny leaks, you can use a little beeswax rubbed in a very thin coat on the back of the backing plate - the bottom part of the slider assembly that is placed between the comb and the slider.
Flatness of combs - especially wood combs - can also be a problem, and you can sand them flat using basically the same procedure described above, then seal them with spray-on acrylic to seal them against moisture. I prefer spray-on because the moisture in brush-on acrylic can cause the wood to swell.
Gapping may be problematic, and on valved instruments you generally want higher gaps than on unvalved instruments because they're receiving a stronger blast of air. But it's not just about tip gapping. Lowering the base of the reed can help, and so can slot embossing. The era around 1987 (i.e., 23 years ago) was one where Hohner had a number of quality problems, and one of them was too much space between the edges of the reeds and their slots, resulting in air leakage. Embossing can reduce the clearance between slot and reed, improving airtightness and response.
You may have missed my response on another forum due to the superspammer attack.......I copied and pasted it below for everyone here:
Here's a brief pictorial from my facebook showing how to tighten the slide clearance on a 270. If you aren't handy with this type of stuff I can do it for a minimum bench fee, it's not a time consuming mod.
http://www.facebook.com/album.php?aid=11663&id=1692631803&l=f5ead59a6c
If you decide to try this, adjust the gaps while the mouthpiece is off. Set them for minimum comfortable leakage during oscillation (not too tight, not too loose), while not stalling out on a moderately aggressive attack.