@Evolene, not to push the idea but since it has some up: frankly the Stoney End kits are harder to put together than any others I’ve seen due to the way the box is built. Four panels glued into four L shaped pieces of moulding. Get just one of those out of line and the whole thing is ruined.
That’s not woodworking it’s being accurate when you glue! Given the relatively low price for one of their finished harps it does not seem worth the trouble to buy it as a kit. I won’t belabor the subject but just quote what one master luthier says: “If you can build a dog house you can build a small, simple harp.”
A bit of history: the modern double came into being after Liz Chifani and Laurie Riley had a breakfast conversation and approached their sponsor harp makers, respectively Gary Stone and Steve Triplett. William Rees then liked the idea and went on to make an entire line of doubles, from 3 to 5 octaves which are still offered today. Dusty finally made the 3 1/2 octave FH26 after a bit of prodding but did not see enough of a market to go any further. I think the lever cost is one major reason that doubles are a small market still.
A lot of things affect the sound of a harp so I won’t comment on specific comparisons other than one case: compare the DS Allegro to the Ravenna to the FH26. I don’t hear much of a difference – at least not enough to justify the cost differences. Others may.
There are three doubles players in my local harp society; one played a Stoney End for years and finally bought a Rees with parallel strings. She says that the difference is a revelation. The disadvantage to that is that to get the most out of the design the sound board should be wider than a single. Rees does that, Dusty and Stoney End do not.
It’s all an adventure and I’m not knocking Stoney End, they make good economical harps. I just wish that more luthiers made doubles – but then I feel the same about wire strungs! “Back in the day” when folk harps started to be popular in the US you had to either make one yourself or have a friend who would; techniques designs and materials have come a long way since then which is a good thing; the downside being that while their are more harp players (and choices) fewer of them want to design their own or understand the technical aspects. I suppose that’s also a good thing, but it seems a pity.