The question to ask is "If oversized resos bring such benefits, then why don't all the horn manufacturers fit them as standard?".I think oversised resonators gives the sax more "volume and bigger" tone. Some techs like them.. Others don't.
It's not like they're expensive, so there really shouldn't be any reason why they don't fit them.
Let's face it, who doesn't want more volume and a bigger tone - especially if it comes for free?
But here's the thing...every physical change you make to a horn results in a change to the performance, and you can only go so far before you push the parameters beyond the design of the horn.
Want a low action? Sure, just pop some cork on the key feet - but you'll reduce the venting, which'll have a knock-on effect on the tone and the tuning.
A high action? Again, this will lead to instability and some tuning issues.
In other words there's always an offset, and the people who make horns know exactly how to balance out the inevitable compromises.
An excellent example of this can be found on older Yamahas, particularly the purple logo models. Most of the reflectors/resonators are of the standard size - but a few select keys were fitted with oversized ones (low D, Eb and low C# - if memory serves).
You could say that the larger reflectors were there simply to prolong the life of those pads that take a lot of punishment (certainly true of the low Eb) - but the low D doesn't, and neither does the C#. And what of pads further up the horn that really take a beating?
Could it be that the larger reflectors were fitted in order to compensate for a fall-off in the tone around these keys?
You also have to take into account the accumulative effect of any modifications, and how it affects the overall balance of the tone across the scale.
I liken it to lowered cars. The designers spend years working out all the geometries - and then the technical team spend months running the prototypes around test tracks...and then the QC bods rig the cars up on jigs and test the things to destruction. And when they're happy, they put it into production.
And then a spotty oik whips out and replaces all the springs and bushes and completely alters the geometry - which works fine when they're simply rolling around a track, but tends to pitch the car into a tree when they're nipping down the shops.
I can tell you why a lot of techs don't like modding vintage horns - and it's because they know the mods can have negative effects. This leads to the clients coming back with complaints of tuning problems and uneven tone, if not instability across the range. They tend to see it as a fault of the craftsmanship and expect the repairer to spend more time (for free, thankyouverymuch) 'getting it right'.
And they feel obliged to try. At least the conscientious ones do. Those with fewer scruples will tell you you just need to 'play it in', or that 'other players have no such problems'.
If you've got any sense you soon wise up and realise that there are a lot of players using perfectly standard horns who just want them to work properly.
All the players I've come across who have a huge, powerful tone all have one thing in common - they've all spent a lot of time working on it. No fancy gadgets, no esoteric tweaks - just years of working on getting the best out of their horns. And if you've ever played alongside our very own Pete Thomas, you'll know exactly what I mean.