Hi Dennis,

This seems highly likely to reignite the Eternal Glue Argument, which will never be resolved. :-)

Mr Poletti’s article is interesting, but hardly definitive. If the question is about the acoustical properties of hide glue versus modern glues such as Titebond, then I would say this is highly dubious. Take a soundboard in a harpsichord for example. I challenge anybody to detect the diffrence between a soundboard jointed up with hide glue as opposed to another glue. Note that we are not discussing the eternal topic of strength and creep under stress here – at least, I don’t think we are.

Where the argument of Mr Poletti that hide glue is superior to modern glues comes unstuck (I’m sorry, I can’t resist the pun) is that for example Epoxy Resin glues (e.g Selleys 308), which indeed we used successfully for building harpsichords in the 1980’s before we switched to Titebond set to a very strong glassy finish and by his reasoning ought to sound even better. But you cannot perceive or measure any audible difference, not in a harpsichord.

As to washing the soundboard with dilute hide glue, well, some people do that. I don’t think it establishes hide glue as having any absolute virtues, as opposed to relative. We use egg white instead. Both just tighten up the grain and protect the otherwise unfinished soundboard timber from the excessive ravages of acid dust abd perhaps moisture, and it does seem to make them sound a bit better, though I think it is a very marginal effect, even possibly imaginary. Unsized soundboards also sound good. And, varnished soundboards can also sound good (e.g. English practice.)

Violins may be a different matter, as they are structurally different to harpshichords, where every piece vibrates, back and belly and sides. But harpsichords, the only place glue could affect the sound is the jointing of the soundboard and the gluing of the bridge. Really, it’s not a significant effect. Those who would claim that would need to prove it scientifically, with data, I think.

Andrew

On 3/03/2016, 21:50, "Harpsichords and Related Topics on behalf of dc" <[log in to unmask] on behalf of [log in to unmask]> wrote:

What are these acoustical properties of hide glue? And how do they differ from those of a modern glue?


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