Jump to content

Growling reed?


Recommended Posts

I've got a strange reed, it's the A below middle C. It firstly has a metallic vibration and then it sort of growls! It's bang on the note but this growl is something I haven't come across before. It looks identical to it's twin (EC) the clearance looks fine, there's no crud hanging around and it's nice 'n shiny, nothing on the surface. I can't see any crack anywhere and it twangs the same as its mate. The valves are new and it's definitely not a beat frequency. Any ideas? It's driving me mad! Thanks.

Andy.

Link to comment
Share on other sites

Check that the slot under the reed , in the wood of the reed pan, is wide enough, long enough, centralised enough that the reed does not touch the wood when it swings down through the slot...

I had this problem with a low Ab reed on an EC.. it had obviously been made incorrectly 113 years ago !

 

If it is a Push reed then the Valve could be flapping against the Pallet board so check the little control pin(s) height.

Link to comment
Share on other sites

Your description sounds like two problems. The metallic noise sounds like a touch and the growl sounds like a valve. If it is one issue only I'd bet on the touch.

 

Touches; if it is a frame touch near the tip it will be very metallic sounding, and it will leave witness marks on the frame. If it is near the root then it will often mean the pitch will rise when you put more bellows pressure on. Typically only makers would see reed root touches. These do not have the same metallic sound as a tip touch.

 

If it is a wood touch that stops the reed from gaining amplitude the note will sound fine at low volumes and and then go weird under pressure. These are also only usually seen by makers! If it is a wood touch that only just touches and allows the reed to gain amplitude then it will sound much like a frame touch but not quite so metallic.

 

If it is a valve it will be the valve beside the reed that has the problem. It will be having trouble staying seated in the air movements created by the reed flapping up and down, and as it unseats it changes the pressure in the chamber and the reed reacts. Why you would hear a metallic noise if it was only a valve I don't know...

 

Good luck

 

Chris

Edited by Chris Ghent
Link to comment
Share on other sites

Thanks Frank, Geoff and Chris. I looked at them both under the microscope and couldn't see any witness marks of touching. No touching the wood either. Cleaned them both and put them back in. The noises have now gone away! Which is really annoying because I don't know what it was. Possibly not seated properly in the slot. Valves seemed fine, they're all new.

The only issue now is a slight clicking, presumably the valve. I'm going to post a separate question because not many people will look at this now.

 

Thanks again.

Andy.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...