The Clarinet BBoard

The Clarinet BBoard The C4 standard

New Topic | Go to Top | Go to Topic | Search | Help/Rules | Smileys/Notes | Log In

Previous Message | Next Message

Re: Tone whole size

Author: Chris P
Date: 2023-03-24 12:43

The RH3 tonehole has to be much larger in diameter compared to RH2 because the notes A/E are effectively forked notes when Bb/F is fully vented - the RH3 tonehole having a tonehole (Ab/Eb) closed immediately below it when playing A/E (xxx|xxo) which needs to be brought up to pitch as a result.

If the Ab/Eb tonehole was always held open whilst playing (like on flute), then the RH3 tonehole could be made much smaller in diameter to bring A/E down to pitch. Same with the LH3 tonehole (for D/A) as that is larger in diameter that it ought to be simply because there's a closed tonehole immediately below it (C#/G#) when playing D/A (xxo|ooo).

There are some high end German Boehm system clarinets made with an automatic A/E vent which is a side key which opens and closes along with RH3 to fully vent the A/E as well as allowing the RH3 tonehole to be made smaller in diameter. The A/E vent tonehole is in a similar location to the existing Ab/Eb tonehole, although usually smaller in diameter and located a little higher up the joint as a result, similar to an oboe forked F vent.

An easy comparison on a clarinet itself is the difference in diameter between the side F# tonehole and the thumb tube - the thumb tube being considerably larger in diameter to compensate for LH1 being held down, whereas the side F# tonehole is a lot smaller as that fingering doesn't have any fingers held down (except the left thumb) to diminish its venting.

On B&H 1010s and other clarinets fitted with an Acton vent, the RH1 tonehole is smaller than that on a clarinet that's not fitted with the Acton vent as the regular fingering for B/F# is fully vented with the Acton vent which compensates for RH2 being held closed.

These are the compromises that are made to make an instrument that's not fully vented play as best in tune. Compare clarinet toneholes with flute toneholes and you'll see the difference between a non-fully vented instrument and a fully vented instrument as flutes have all the toneholes open (the G# tonehole being doubled with the double LH3 toneholes and the Eb key is held open whilst playing most notes).

Former oboe finisher
Howarth of London
1998 - 2010
The opinions I express are my own.

Reply To Message | Avail. Forums | Flat View

Newer Topic | Older Topic

Topics