The next thing on my shopping list would be a voice flute with interchangeable barrels at a'=415Hz and 440Hz: I've also been advised to consider Tim Cranmore, and my recorder teacher waved her new instrument by him at the last SRO meeting and then played a few beautiful notes on it for us....

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Having said that, the first thing I will do is head down to Greenwich if at all possible in November, to sample as many as I possibly can. My treble I'm happy with - it's a Moeck Denner model in box, so a step up from a Rotty, and I think they're hand finished even if not handmade. It is incredibly flexible at the top end, able to produce any note I ask of it, including some of the unreasonable ones with too many ledger lines - and has a clear tone which is fairly powerful, but is not everyone's cup of tea, and certainly not a consort instrument - too attention-seeking. The early models all tended to be a bit flat, but I understand Moeck now has its standard tuning at a'=442Hz...
So - if upgrading, yes, I'd go for handbuilt by a maker rather than factory produced or from the big companies: on the whole I tend to prefer to stick to boxwood, the traditional wood for recorders. I'm wary of ebony and rosewood with their increased risk of causing dermatitis, and like the bright sound of box very much - or pear for bigger and consort instruments.