Tech/maintenance Leak problem on low notes not showing with leak light?

[fibracell]

Just wondering if any one can help.

I have 2 tenor saxes same make and model. One of them plays great and I can subtone low C# down to Bb. The other one I can't go below D. I put the leak light in and it doesn't show any leaks, but somewhere there must be a leak.

any ideas what the problem might be?

 

[Pete Thomas]

Have you checked the G# linkage?

Saxophones - Low notes and Leaking G# issue

Problems with leaky low notes? The issue is very often your G# The G# on modern saxophones has quite a complex mechanism. All saxophone players need to know about adjusting the tabbed/articulated G# as it is one of the most common, and yet easily fixable, causes of leaks. The first thing we...

cafesaxophone.com

NB: Hope you dont mind, I've edited the title to be more specific

 

[fibracell]

thanks this looks great. I'll have to read this and check everything!

 

[fibracell]

seems to be ok. What is the purpose of the screw on low B key that links to the C# key?

 

[Stephen Howard]

seems to be ok. What is the purpose of the screw on low B key that links to the C# key?

The 'official' purpose is to prevent the low C# from opening if your fingering is less than precise when going for a low B/Bb - and you catch the low C# touchpiece.
Sounds great - but in practice there are usually a lot of caveats; the first of which is that the mechanism often relies on a lot of long 'flying arms'. When you have key barrels that long, coupled with long arms, there's always going to be a lot of key flex involved.
Now add in any wear in the action - or poorly-adjusted point/pivot screws, and/or a squishy buffering material on the adjuster, and what you're left with is a mechanism that only really works when everything is 100%. And saxes tend not to stay at 100% for any great length of time.

So, you set the adjustment so that the low B (when closed) keeps the low C# cup key firmly closed - but in order for this to happen it often means that the force required to do so means the low B is 'held off' (as in it cannot fully close). So you set the adjuster so that the low B can close...but now the C# can open slightly if you fumble the fingering.

It will only work properly when everthing is nice and tight and the pads are seating 100%. The rest of time I feel you're best served as considering it as a mechanism that 'kinda' gives you a workable low B/Bb if you fumble the fingering.

The fix for this is either spending out to have the toneholes properly levelled and the pads precisely seated...or practice a shedload of low notes until you learn not to touch the low C# key when going for the bell notes.

 

[Grumps]

The other one I can't go below D. I put the leak light in and it doesn't show any leaks, but somewhere there must be a leak.

Just to clarify, you're not just looking for leaks at the bottom end of the horn, but up top too. Right?

 

[fibracell]

no I think it's at the bottom. But, I can still blow all the overtones off the low Bb,B C C# up the 6th overtones.

 

[Dr G]

If you have a leak at the bow seal, you’ll not detect it with a light.

 

[turf3]

Well, several things.

First thing I'd check is the G# hold down. If you're talking about a modern horn, everything below D will want to lift the G# pad unless that hold-down is just right. And if you screw the screw in even the tiniest bit too far, now the bell key pads won't close.

Another factor here is that the surface on which the little cork-tipped screws bear is almost never perfectly flat and perpendicular to the axis of the screw, so the cork deforms into a tilted or cupped shape. Then when you turn the screw, the edge of that cork is what's pressing, not the entire surface, and it deforms quickly due to high load. So it might look fine for 10 minutes and then it's deformed enough not to be doing its job. The long term cure is either to modify that mating surface so it's flat; perpendicular to the axis of the screw; and large enough that none of the cork hangs off the edge - or, to put a flat-tipped screw and move the cushioning material to the key cup. (Which is usually what the adjusting screw bears on.)

Next thing is the low C# hold down. As Stephen points out, it's kind of a bogus mechanism, and I won't get into the details, but you'll probably have to adjust it so that it allows the C# to crack open ever so slightly when playing B, just to keep it from holding the B open. However, misadjustment of the C# hold down won't affect low C# or low C.

Third thing is leaks up high on the horn. Just because the higher notes play fine doesn't preclude a leak up there acting as an unwanted octave vent for bell key notes.

Next would be tenon fit (wrap the joint with electrical tape and see if the problem goes away) or bell/bow joint leak (wrap the joint with electrical tape and see if the problem goes away).

Lastly would be a crack in the actual material of the horn itself. I have a bass sax with a stress crack in the loop area; by the time I found it I was tired, so I just patched it with some aluminum tape and it's still holding 10 years later.

I'm going to bet on the G# holddown from the description - everything plays fine down to D then goes out the window with low C# and below.