+1 for @Colin the Bear's tip about using a reed clipper (or sandpaper) to adjust reeds. And +1 for
@thomsax's tips. Though TBH (IMHO) if a reed is simply 'worn out' adjusting' the reed - or its position - may be of limited use. Perhaps in extending its life as a 'practice/rehearsal reed'.
There was a period in my 'beginner years' in which I discovered the 'dark arts' of reed adjustment: breaking them in gradually, noting (on the reed in pencil) whether it played fine 'out of the box' or whether it was slightly 'too stiff' (and needed a wee bit of sanding) or 'too soft' (and needed a miniscule amount of clipping). It took me some time to learn to 'adjust' reeds: 'over-adjustment' leads to potentially playable reeds that went straight into the waste bin.
Expanding on
@thomsax's tip, my initial 'reed adjustment' process changed when I first read Emeritus Professor Steven Mauk's article on '
reed placement and adjustment'. I've followed the principles of this article ever since. Mainly by placing the tip of 'thinner/older reeds' slightly further away from the mpc tip. And placing the tip of 'new' or 'thicker' reeds much closer to the tip of the mpc. I still do this today at every rehearsal when 'setting up'. Just to find the 'sweet spot' of positioning any reed on any mpc that enables me to play the widest range of notes (from low B♭ to high F) with the greatest 'ease' and with the 'best' tone. IMHO (as an amateur), selecting and positioning a reed (and ligature) on the mpc is often a compromise between hitting both the 'low notes' and 'high notes' well. And also between being able to play at
pp and
ff.
I've posted this link to Steven Mauk's article many times on the café. Just because I personally found it so insightful and helpful.
No, it doesn't solve the problem of 'worn out' (or damaged) reeds. But it
has enabled me to make minor adjustments during 'set up' and more importantly 'on the fly' during rehearsals and performances without having to stop playing and swap reeds.
IMHO experience, reeds don't (often) 'suddenly die'. Rather, they gradually 'degrade' (become softer, less resonant, etc) over time. As you say, "in hindsight, I have had reeds close up before during rehearsals or gigs (never as bad as this) and thought it was me tensing". So please, just learn from this experience (which we
all go through!). If a reed doesn't feel right for you, it probably isn't.
As you gain more more playing experience, I'm sure that you'll become more able to adjust to playing any reed. 'out-of-the-box'. As
@Nick Wyver said.