Problems with noisy Marimba Resonators (Qs ALEJANDRO SUAREZ)
-----Original Message----- From: ALEJANDRO SUAREZ Sent: Wednesday, 28 November 2007 10:55 AM To: firstname.lastname@example.org Subject: marimba build from SpainHi Jim,
Iīm Alejandro from Spain.Your site itīs very very interesting. Here in spain it does not exist some people with that to speak of these subjects I build my 4 1/3 own marimba in this summer 2007. I used many information about this and iīm very happy of the results. But I have a problem with the sound. I used a PVC (60x1,8 and 50X1,8) for my pipes. In the high and mid register the sound is really good (G3-C7) but the sound in the low register itīs bad. In this notes I listen a buzz noise in the pipe. I try to separate the pipe from the bars and the it disappears but the quality and volume it decreases. If i put the pipes at 2 cm from the bars = buzz. If y put the the pipes at 7 cm from the bars the buzz it desappears but the sound itīs poor.
Whatīs do you think about this?
When we can buy the "building guide and instructional videos for marimba?"
Get These Comprehensive Plans & Instructions with Video!
The P3 marimba building guide is due for release in about 2 to 3 weeks. [Now available!] The www.makeamarimba.com website is being updated tonight with some sound and video info if you want to have a look.
About your specific problem:
Of course it might also simply be that your resonator is just not wide enough to produce the volume you are after, but 60mm should not be too bad. Commercial instruments tend to use slightly bigger diameter pipes on the bottom of a 4 & 1/3 - about 70mm for the A-c then 65mm etc. 60mm is not far off though, and the result should not be that different assuming that the bars are OK. As your middle register bars sound good, there is no reason to think that your low ones would be bad.
When a resonator is placed too close to the bar, 2 things happen.
This is why I suspect that your low resonators might be too short. With the bar close, the resonator is lowered and becomes in tune with the bar. It also takes more energy from the bar, so it is louder. These two things make it sound good, but the growl makes it sound bad. If the resonator is lowered away from the bar so the growl disappears, then it will naturally be a bit softer, but it might also in your case be becoming out of tune with the bar. This would cause it to be both less resonant, and also of badly defined pitch. (there is actually two notes competing with each other)
All of this is of course a bit of a guess, because I can't hear it for myself, and I'm not sure what process you are using to tune the resonators.
Best of luck!
answers by Jim MCCarthy - 19/03/2005
For more help on instrument building you can email Jim.