On Sat, 01 Apr 2006 05:56:14 -0800 EUGENE BRAIG IV wrote: ----- Original Message ----- From: Alexander Batov <[EMAIL PROTECTED]> Date: Saturday, April 1, 2006 8:07 am Subject: [VIHUELA] Re: Anjo com Viola
>> I think you are quite right. In pre-soundpost era of the viol, for >> the rather flat top with lots of soundholes this might be indeed the >> best solution: freeing the top from excessive string pressure, >> balancing the sound throughout the instrument's range (important for >> consort playing!) and getting rid of wolf-tones, all at once ... >A thorough skeptic, I would be a little reluctant to give this rather odd >looking design any such attributes until an instrument like this was built >(or >discovered), its sonic behavior was quantified, and the results tested >against >what we know as more conventional designs. I would be equally reluctant to classify it as odd looking although I'm not a thorough sceptic. > After all, this bridge design certainly did not persist. We can probably find a good number of things that didn't. However, this doesn't make them less respectable. Fluted-ribs just spring to mind ... > (I'm not an acoustic physicist, so I'd appreciate the opinion of anybody > who >is.) That would be great! I'd appreciate qualified opinions too and before one of those joins in (well, nobody did in the last few days), lets see how far we can go ... by mapping a mental model of, as you say, a "sonic behaviour" of this ''odd-looking design''. Of course it cannot serve as a substitute for the test results you are seeking but ... we're not that serious here are we? > Vectors to represent the distribution of string pressure would be wacky. >The transfer of the tension of the treble strings to the soundboard would >be at >an extreme angle and focused wholly on the inner edge of the bridge's foot, >while the bass strings would be much more directly focused into the >soundboard. You do seem mostly concentrate here on the static picture but it's a dynamic one which is more telling. >From the perspective of purely mechanical action, the back will take care of a larger portion of pressure from the treble strings, thus relieving the soundboard, while the latter will mostly be subjected to the downward pressure of bass strings. However, the dynamic picture wouldn't be hugely different from that in a 'conventional' viol which is equipped with a soundpost. The difference would only be in the positioning of the pivoting point for the bridge: in a 'conventional' viol, this is situated on the soundboard, in the area just above and in vicinity of where the soundpost is placed, in an 'odd' one - where the extended foot of the bridge rests on the back. In this last case the vibration generated by the treble strings, although partly 'consumed' by the back, would still be present, in its largest portion, at the bass side of the bridge and subsequently re-enforced by the soundboard (well because the top of the bridge is a fairly rigid structure, which favours propagation of high frequency vibrations). Also because the soundboard is neither as stiff nor heavy as the back is: both these qualities kill vibrations but help to provide a firm pivoting point for the extended foot of the bridge. The key difference from a 'conventional' design would be that the soundboard is now let free to vibrate with no hindrance from the static pressure of treble strings. Although this 'odd' way of construction may seem hardly necessary on, say, Baroque era viol, in particularly after the introduction of overspun strings, in the era of thick gut basses the extended bridge foot construction could have made a noticeable difference in boosting bass response. I actually know one surviving instrument (in the St-Petersburg museum) which has exactly this extended bridge foot construction going through the cut-out in the soundboard and resting on the back. It has seven strings (all gut, including very thick basses) and of the size of a small double bass. It seems to have been made in Germany c.1720s. I did try to bow it but because this was quite a while ago I can't recall the impression of the sound. Perhaps I can compile a report on this rare specimen if I manage to visit the collection later this year. > The treble strings would be directly engaging the back plate. It's just so >odd. In a way, as I've just explained, they wouldn't! This long foot design is more or less what the soundpost does in a 'conventional' viol (which is of course a more sophisticated one, for by moving the soundpost we can change the degree of soundboard participation in the production of treble range response of the instrument). With the long foot construction the back plate would be far too rigid and heavy to be able to respond effectively to treble strings. Again, it's main function would be to provide a firm pivoting point. To further explain this, consider the following experiment: bow the first string of a viol and simultaneously grip the bridge with left hand fingers in the area of the first string or further below, at its treble foot. Depending on a quality of the instrument and its setup there will be either noticeable drop in the amplitude and timbre of the sound, or less noticeable or ... there will be hardly any change in the sound at all! So even with the handgrip blocking bridge vibration at the treble foot (and, as a consequence, the soundboard area surrounding it) the sound of treble strings may still hardly change. Actually on viols with over-thinned, sinking tops that have, as a rule, a rather shriek sounding trebles and disturbing wolf-tones a bridge with the extended treble foot design might actually help to cure the problem, although not many viol owners would agree to spoil the soundboards of their viols. Richard Jones, here in UK, makes a set of Renaissance viols without soundposts in them. They have rather heavy soundboards, which obviously helps not only to withstand string tension but to kill unwanted vibrations too, or at lest make them less prominent. These viols sound remarkably well when played together although the sound of thick gut basses, as one might guess, is rather subdued. I would venture to assume that the viol with the bridge's treble foot going through the cut-out in the soundboard on the picture that Roger pointed us to is the lowest pitched one in that consort. Nobody knows for sure when the idea of using the soundpost in the viol became dominant. In a small number of surviving 16th century viols soundpost plates on their backs are of later origin. Their soundboards, although thinned down during later conversions, were noticeably thicker than those of Baroque viols. It's always a rather difficult task to satisfy both worlds in a bowed musical instrument, so I would imagine that the extended bridge foot design might have come as a precursor to the idea of the soundpost but was, perhaps for some practical reasons, abandoned. Who can ever tell ... Alexander To get on or off this list see list information at http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html
