Given the number of antique flutes that seem to be best in tune with themselves with the slide pulled out a long way (2cm or more in some cases) I think it would be nice to know the useable tuning slide length in addition to an embouchure to C# hole measurement. These two pieces of information would nicely complement the C# to D# measurement.
How about this question – at what point along the tuning slide is a certain fifth interval in tune, and what is that length, relative to the pitch of A at that scale? Well we can’t use low D of course, nor E, but maybe G to middle D? or the fourth up from G to C? That would tell us something useful. Experiment with the tuning slide until you get a pure fourth or fifth, and at that point, is A at 440? And at that point, what is the length from embouchure to C#.
Or much simpler than that: What is the ratio of D#-C# to embouchure-C#? Hey now, that’s an interesting notion.
If we want a good approximation of the range of frequencies the flute will play for the note A, then we should measure the distance from the embouchure to the hole that vents A, and we should also measure the length of the tuning slide. From those two measurements we may be able to get a rough estimate of the amount of slide extension required for this particular flute to play A=440 hz. Here I’m assuming that there is not a wide range of distances from embouchure to A hole that all play A = 440 hz on different flutes (for example with different bore profiles), but I may be wrong about this …?
But continuing this line of thought, if we had the embouchure to C# hole measurement (with slide closed), and the C# to D# measurement, we could then calculate the embouchure to C# and the embouchure to D# measurements for the tuning slide extension that was required to get A=440hz (you get the first by adding the slide extension to the embouchure to C# distance, and you get the second by adding the C# to D# distance to that). This should give us a good idea of the degree to which this flute will be in tune with itself at A=440 hz.
But this line of reasoning might be overly simplistic. Is it reasonable to assume that the ratios of these distances (emb - C#, emb - A, and emb - D#) should be constant for flutes that are in tune? For example, how much can factors such as bore profile and tone hole sizes influence this? At least you can see tone hole sizes in photos, and get a rough idea of whether a flute has unusually small or large tone holes, but bore profiles …
Responding to Terry, and thinking about a recent related discussion on Earlyflute, I chose the emb-C# because, together with the C#-Eb and the SL, one can then do some other sums which one could not do if one chose another tone-hole without needing other supplementary measurements. My thinking was predicated less on trying to determine details of the tuning/scaling in sound terms than on asking a small set of practical Qs of a non-specialist vendor. I was also thinking about trying to establish comparative physical info between flutes with a view first to see how their constructional details vary. Of course those affect tuning and one would wish to move on to looking at the actual sound production/tuning, but you need hands-on contact with the flute for that.
With regard to this particular flute and to compare it with others whose measurements I have to hand, I would also like to know the C#-E (R3) length and the emb-edge of barrel socket distance (“SL” of head/barrel). In combination with the other 4 lengths already on my list, those would enable one to establish what parts of the flute were having their proportions changed. If you look at the comparison I made above between #6409 and #4683, you’ll see what I’m getting at. One cannot say anything absolute about design/optimum pitch or scaling/intonation from these observations alone, but when the intonation behaviour of at least one of the sample flutes is known, one can make some inferences about the probable behaviour of a (distant) comparator.
why aren’t we seeing anything discussed on the relative placement of the embouchure to the cork? or is that of inconsequential consequence (how’s that for a phrase?)?
have a rudall here that just was awfully dicey at the bottom end, wasn’t where it should be tone-wise and clarity. After the usual pad adjustments, etc…i took a whack at the cork and pulled it back for a nick of about 1/8". Boom. That did the trick.
Anyways, i figured with all the mathematics going on here that even a trivial amount could make a key difference. I’m hardly the scientist or mathemetician you boys seem to be.
Easy answer to that, David. The stopper’s position is not a fixed design feature; like the tuning slide, it has a range and it was expected that the player would adjust it to suit. Nor, even if one had a fixed position stopper, could its distance back from embouchure centre tell us anything helpful in trying to determine the likely scaling or design pitch-range of a given flute. Sample bore dimensions at chosen points and the full set of tone-hole placements and sizes would tell much more, but are far too complicated even for an expert to take casually, let alone an uninformed and not necessarily highly literate eBay vendor. That line of detail requires special tools and hands-on inspection, just as sound-testing does.
I’m not saying that stopper position/adjustment isn’t important in setting a flute up to play its best/how you want it to, but it has no relevance to the present discussion.
exc explanation, Jem. Glad I poked my head up…but that’s as far as I wanted to put it on this topic! Completely understand the physics of it all…but glad I don’t have to make a living at it!
OK, vendor of #7232 has given some more measurements. I think the following is rather interesting - looking forward to Terry’s analysis!
All measurements in mm. I haven’t checked additions - there may be the odd (insignificant) mm discrepancy!
OL = Overall Length; SL = Sounding Length; E-BE = centre of embouchure to lower end of barrel, slide closed; the rest should be obvious - hole-centre to hole-centre.
Flute date OL SL E-BE Emb-C# C#-E C#-Eb Eb-end
#2130 c1833 *661 *586 162 221 200 261 *104
#4683 c1843 661 578 158 217 200 258 102
#6409 c1851 650 569 155 213 201 255 100
#7232 ?late C19th 650 565 155 215 200 248 100
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- of course, #2130 has a Bb foot - these measurements, taken to the centre of the low C hole are not strictly comparable to the open end terminations of the other three flutes, but it is interesting how similar they are. FWIW, the measurements to the extremity of the low Bb foot are respectively 746, 672 and 189.
I think it would be fascinating to get some more comaparators across the Rudall date range! Adding in flutes by other makers would be interesting too, especially from the Wylde/Fentum group. I realise, however, that this is to some extent revisiting work Terry has long ago done and published - but not SFAIK/can tell with a sample limited to a single major manufacturer.
As for interpretation, to me the stand-out thing is the almost total lack of change in the C#-E length - to whit, no fundamental change of the scaling over c 50 years. What they seem to have done (a trend Terry identified in his old research) is to shorten the head &/or move the embouchure down-tube and reduce the E-Eb distance (primarily by shortening the lower end of the lower body joint), plus a small shortening of the foot (at both ends).
Of course, the actual tuning of each flute will be individual, with variations in tone-hole sizes, maybe undercuts (not much sign of it on the ones I have examined) and bores, not to mention the possible influence of different embouchure cuts. But, FWIW, I suspect that, as #6409 still has a slightly flat foot, there’s a good chance that #7232 will play with good intonation at 440 with a long-ish slide extension and maybe even a slightly sharp foot.
I like this game, I wanna play too! 
Here are the measures of my Thomas Glen:
T. Glen c1850 654 577 167 217 201 257 106
It looks like the right hand section is shorter than usual, but the headjoint is slightly longer, giving the same distance Emb-C#. I’m surprised with the Eb-end measures, because the foot notes on my flute are very well in tune, not flat at all. The rest fits very well.
Given the sounding length, what are the odds this could be made into an Eb flute by having a new head or barrel made? I’d really like an Eb flute and this just might be a cheap solution provided it doesn’t go into the stratosphere price wise. I’m very fond of Boehm style footjoints especially since my carpal tunnel cursed hands are loosing the strength to operate a claw style foot.
My antique gets close enough to Eb when the slide is closed, but the tuning within the scale becomes quite strange. I suspect that this Rudall will get more expensive than any antique Eb flute…
Argghhh! Bad day - I’m preparing for a trip up to Canberra to do some work on the National Carillon and won’t be back for a few days. But some quick thoughts.
I think it would be fascinating to get some more comparators across the Rudall date range! Adding in flutes by other makers would be interesting too, especially from the Wylde/Fentum group. I realise, however, that this is to some extent revisiting work Terry has long ago done and published - but not SFAIK/can tell with a sample limited to a single major manufacturer.
That early work made us aware of some of the changes that occurred, and lead to concepts like the C#-D# length. It could do with some updating to take better advantage of what it told us!
As for interpretation, to me the stand-out thing is the almost total lack of change in the C#-E length - to whit, no fundamental change of the scaling over c 50 years.
What they seem to have done (a trend Terry identified in his old research) is to shorten the head &/or move the embouchure down-tube and reduce the E-Eb distance (primarily by shortening the lower end of the lower body joint), plus a small shortening of the foot (at both ends).
You can see why I avoided C#-E as a scaling indicator! I notice that Prattens uses a narrower C#-E, easily seen when compared to my RC 7120 which has about the same C#-Eb. I also notice that I have reduced the C#-E on my own Rudall models. So there’s something interesting there to think about.
I’ve taken your figures, added a few I have and graphed them to make it easier to see the trends:
The most significant change is the C#-Eb in brown. Note the general downward trend flattens at RC7120. I think that’s because High Pitch was abandoned in 1895, and this flute was made in 1898. Note that the difference over the period represents nearly a semitone, certainly more than enough to bring 430 up to High Pitch, or 420 to Modern pitch.
The other changes seem to flatten out around the mid century, but we really need more data to confirm that. Happy to add more from any other Rudall original owners, so please feel free to supply data.
I think we’d need to keep different makers data separate at first at least, to avoid confusion. I imagine we’ll see similar drifts in their dimensions.
What’s very interesting is that we don’t ever seem to see the full impact of High Pitch. Given that the pitch at the start of the century was 430 or less, at the end of the century is 440, and from about the middle of the century around 453 - we should expect logically to see big dips in all the dimensions in the middle. I’ve illustrated what we might have expected to see with the arbitrarily-placed wavelength trace dotted. The only faint dip is in the aqua Emb - C# but it’s not very significant. I interpret this to say that Rudalls didn’t aim their 8-key flutes at the professional market. The flutes could make it up to High Pitch, but were never going to be in good tune there.
Better get back to packing!
Terry
Not a chance. Not without major surgery tantamount to vandalism, and then the success of the outcome would be dubious. Look at the C#-E length, which is that of a core scaling originally aimed somewhat lower than a 440 D scale. The foot would also be too long in proportion.
I think it would play better as a D flute, just make a new head joint or even a longer barrel if necessary. It would be interesting to see if the cone as changed on these later flutes. When I measured another late model, the cones was more like a straight taper, then the earlier Rudall’s that had the 40 mm cylindrical section in the upper section…
Good grief! Have you guys seen what this one went for? $2,787. That’s not much less than David got for his beautiful patent head, big-holed, glassy-bored, silver-keyed beast.
I thought the market was supposed to have dropped its bottom? (As it were.)
I missed the estimate on the flute by $50, I guessed $2765.00… But I only bid $1,500…
Who got it? Was it you David? After that diversionary tactic, of saying that it would only go for $1,000… Who ever got it buys smoking pipes also… Makes me want to put my RRC up on EBay!
You said $2,650. Still, not all that far out. Bit more than $50 though.
But why did it go for so much? There’s those cracks to attend to as well … 
Pipes, eh? Sounds familiar watch the feedback to see, but I reckon that’ll be ‘clearcreek’, not unknown in this parish, noted Rudall collector. I guess the lateness of it (possibly/pro tem ‘latest known’ conoid Rudall concert 8-key flute) makes it more collectable, and our deliberations here may have ‘helped’ a bit over the probable pitch/scaling and playability. The cracks would affect value somewhat, but are very routine fixes and not a major playability issue once repaired.
I know the cracks aren’t insurmountable, Jem. But you have to factor in the cost of fixing them, which is not cheap, and then it’s probably not the most desirable from an ITM point of view, which is where I assumed the market was. That, and the fact that it had GS keys. Oh, and your estimate was about half the eventual price, yes?
Can’t do an accurate sterling conversion just now, but while it went well beyond my core prediction, it can’t be far off the top of my wider envelope, which I did claim the right to revert to!