Octave Vent Split

[TheRuzhyo]

I was wondering if anyone shed some light on the purpose of an octave vent split. My aristocrat alto has one and all it does for me(that I know of) is make the second register A sound crummy. Anyone know about those things?

[rrex54]

In theory, each separate note in the first octave/register would need a separate octave pip for optimal sound in the second register -- because the wave length of each frequency differs. However, in practice, makers found that two vents usually served the purpose. The problem, as you have discovered, is that the notes closest to the switch between the body pip (G#) and the neck pip (A) may be compromised -- and it is generally the A on alto as I recall.

During the 30s Buffet produced a Powell model within its Evette & Schaeffer line that had 3 or 4 vents -- and I believe the fabled (or perhaps the more apt term is fantacized given all the problems we've heard about in actually getting these instruments) Unison Goodson model sax uses three pips.

BTW the only problems I have tended to have around that swithover point has usually been related to an unacustomed reed strength (too strong). However, you may have a leak or adjustment problem involved. For player related issues, try a different reed or reed strength and/or perform overtone exercises to gain a bit more control. For leaks, hie thee to a tech!

PS you might be thankful to have a later instrument. The first saxes had separate octave keys. They didn't automatically switch between the two pips.

[TheRuzhyo]

I think you misunderstood. I wasnt very clear on what i was talking about. On my alto, on the top octave vent there is a piece of metal that goes down the middle and splits it into two parts. I'm not talking about there being two different vents.

[rrex54]

Sorry for my confusion. You've got me as far `s your question is conerned. I don't think I've ever heard/seen anything like it.

[GHawk]

I had a MkVI once that had a "bad" octave vent. The second octave A had a really annoying airy sound to it. A tech friend of mine glued a small piece of cork onto one side making the hole smaller and voila, no more whistlin'.

[TheRuzhyo]

This isnt the same as that though, its a thin strip of metal right down the middle of hole.

[GHawk]

Plug one side of it.

[awholley]

I had a teacher put a tiny flat piece of brass down the neck octave pip of my Mark VI alto a long time ago and it really helped the high A not be so sharp and airy.

That train of thought is probably why the divider is in your octave vent. Perhaps it is dislodged, or maybe it isn' doing its job enough... I didn't see a description of the bad sound, so it's hard to say. If it's still sharp and airy, experiment with a small strip of nylon panty-hose over the vent and see if that helps. Some people tie these around the neck octave pip.