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Choris "based On" A Diapason


sbarber49
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Since I'm at home with a cold:

 

I've wanted to ask this for years, but was embarrassed to show my ignorance. Getting too old now to worry!

 

There are often references to the chorus on a manual being "based on" a certain stop. Does this involve a subjective judgement or is there a technical definition.

 

Sorry about spelling of topic title. I don't know how to edit this.

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Since I'm at home with a cold:

 

I've wanted to ask this for years, but was embarrassed to show my ignorance. Getting too old now to worry!

 

There are often references to the chorus on a manual being "based on" a certain stop. Does this involve a subjective judgement or is there a technical definition.

 

Sorry about spelling of topic title. I don't know how to edit this.

 

As I understand it, and I am more than willing to be corrected if others know better than I do, to state that a chorus is 'based on' a particular stop means that the chorus on that manual is understood to use the stop in question as the 8' rank supporting the upperwork, 4' and above.

 

On a typical British Organ of the 19th century, it would normally be the Open 8' (or one of them on Great Organs, which one depending on the tonal ideas of the builder), but in late 20th century instruments built on neo-classical lines it may be a Stopped Diapason or some other 8' flute of suitable design.

 

Hope this helps.

 

Regards to all

 

John

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As I understand it, and I am more than willing to be corrected if others know better than I do, to state that a chorus is 'based on' a particular stop means that the chorus on that manual is understood to use the stop in question as the 8' rank supporting the upperwork, 4' and above.

 

On a typical British Organ of the 19th century, it would normally be the Open 8' (or one of them on Great Organs, which one depending on the tonal ideas of the builder), but in late 20th century instruments built on neo-classical lines it may be a Stopped Diapason or some other 8' flute of suitable design.

 

Hope this helps.

 

Regards to all

 

John

 

Yes, but how do you know? I play a fine Harrison from 1917. I wouldn't dream of using the large Open Diapason as a basis for a baroque chorus (in fact very rarely use it at all) but might Arthur Harrison have considered the chorus to based on it? I'm wondering if it's an exact science - it always seems to be stated as an incontrovertible fact, rather than an opinion, that the chorus of such and such an organ is based on, for example, the small open or the 16 foot.

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They can be used as -very beautiful- Solo stops, or in combination

with the II and the III; then, the result resembles to the Cavaillé-Coll

"4 jeux de fond" (i.e. Montre, Flûte harmonique, Viole de Gambe and Bourdon),

or be drawn in louder combinations with reeds and Mixtures.

Those stops were obviously from Hope-Jones origin, like the reed voicing

peculiar to Arthur Harrison (Tromba).

 

Pierre

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They can be used as -very beautiful- Solo stops, or in combination

with the II and the III; then, the result resembles to the Cavaillé-Coll

"4 jeux de fond" (i.e. Montre, Flûte harmonique, Viole de Gambe and Bourdon),

or be drawn in louder combinations with reeds and Mixtures.

Those stops were obviously from Hope-Jones origin, like the reed voicing

peculiar to Arthur Harrison (Tromba).

 

Pierre

I occasionally use it as a solo stop in hymns, usually tenor register, but "beautiful"? - I think not!

Nor do I use it for a C-C Jeux de fond: I tend to use the small open, Hohl Flute and Stopped Diapason coupled to the swell open. Sometimes omitting the Hohl Flute. The big open is just TOO big (not to mention foghorn-like.)

I do sometimes use it as part of the Full Organ in English music (normally with full swell and octave)

 

However my question is: how do you know which stop(s) a chorus is based on: can it a matter of judgement/taste? Is there room for a difference of opinion? After all, 2 organists might not use the same 8' stop as the basis for a baroque chorus - it might be 2 stops, indeed. Or it might be the 16 foot. Does it only apply to a Baroque chorus? I use different foundation stops for different types of sound.

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It is rather simple: when I visited british organs in the 70's and

beginning 80's, I had my attention drawned upon the fact the II

was the basis of the chorus by the organists themselves who

made me see and ear the instruments.

It was customary, at least then: "draw the II, not the I". The I

was too big for the Diapason chorus, it was made for other purposes.

An exception was Worcester Cathedral: there, the whole tonal structure

was based upon the leathered I; as a result, this organ "came from another

world" in the british scene.

 

Pierre

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Since I'm at home with a cold:

 

I've wanted to ask this for years, but was embarrassed to show my ignorance. Getting too old now to worry!

 

There are often references to the chorus on a manual being "based on" a certain stop. Does this involve a subjective judgement or is there a technical definition.

 

Sorry about spelling of topic title. I don't know how to edit this.

Sorry to hear about the cold - there's a lot about (and I've succumbed too)

 

In a nutshell, the ranks of pipes in a diapason or principal chorus (e.g. 8, 4, 2 2/3, 2, etc) should relate to each other in pipe construction, design and scaling (the relationship of the circumference of the pipe to it's speaking length). The reason for this is so the sound from all the pipes blends into a single, unified sound and makes the chorus sounds homoegous and pleasing to the ear.

 

The most simple type of chorus is the "straight" chorus. In a straight chorus, a pipe of a given length (e.g. 2' C) will be the same, whether it sounds middle C in the 8' stop, tenor C in the 4' stop, bottom F in the 2 2/3 stop or bottom C in the 2' stop. In a perfectly straight chorus, they will all produce the same power and sound. The effect of this chorus is very strong, with a lot of harmonic interest. It can make a bold, ringing sound which is very effective in a large space, where the air will attenuate the higher frequencies.

 

In a smaller, intimate space, the effect of a straight chorus can be rather wearing on the ears. So many builders would make the higher pitched pipes in the chorus quieter. The easiest way to do this is in the voicing: an easy way is to make the hole at the bottom tip of the pipe smaller , while means the pipe gets less wind and so sounds quieter. This type of chorus can sound very appealing, with a lot of homegenity and excellent blend. But if the pipe is made to speak too quietly, the sound of the higher pitched pipes can become bland and unappealing, with problems starting the pipe speech.

 

Another way to make the pipes to sound quieter is to make them smaller scale - so they're narrower. This allows the higher pitched pipes to keep a harmonically interesting sound while at a lower level of output and gets around the problems listed above.

 

Builders have experiemented with many different relationships between the scalings of the pipes in the choruses over the years. One of the simplest methods is to rescale the pipes one or 2 notes small each time you go up. So the 4' stop at bottom C will have the same diameter as the pipe in the 8' rank at tenor D (i.e. not tenor C), bottom C of the 2' stop will be the same scale as middle e of the 8' stop (i.e. not middle C) and so on and so forth.

 

One further factor to throw into this is halvings. You would imagine that the diameter/length relationship of the pipes remains constant throughout their lengths so a 4' pipe will have a diameter exactly half that of an 8' pipe because it is half the length. This doesn't happen. Lower pitched pipes will need more hamonics in their sound so the human ear can detect their pitch more quickly but the higher pitched pipes would sound too shrill and thin if they were the same scale. There's also some technical details of the pipes to take into account as well as they get smaller. But basically, most ranks of organ pipes halve their diameter somewhere around every 15th note (i.e. so tenor D# will be 1/2 the diameter of bottom C).

 

Now, if you apply that to re-scaling of the higer pitches above you'll find that bottom C of the 4' rank is the same diameter as tenor or F in the 8' rank and the gap widens as you go to the 2' stops - Bottom C of the 2' rank will be around the same diameter as middle G or A of the 8' rank.

 

Different builders had slightly different flavours to this. In the earliest organs, the relationship between the pipe circumference and length was geometric. If you plotted a graph of pipe length against pipe circumference for a single rank of pipes on a graph you'd get a straight line, with the length halving every octave (every 12th pipe), the circumference halving whenever the organbuilder had chosen (typcially somthing like every 15th pipe). Dom Bedos describes a method where the builder would use a dulcimer to determine the scale of the pipes. Basically, you had a big board with a diagonal line on it. The builder would put a piece of pipe metal against it at the length the pipe was to be and measure off from the side of the board to the diagonal line the width of the pipe (this would determine the pipe's circumference). Hey presto, the organ builder has his pipe metal of the correct dimensions and he doesn't even need to be able to read.

 

It is highly likely that this method was used until surprisingly recently. The evidence from the choruses of the Victorian organs of Hill, Willis, Gray and Davison and J.W.Walker seem to conform to this geometric progression (or variants thereupon) until the years between WW1 and WW2, where the demand for new organs dried up and the majority of the work turn to rebuilding. It's a bit difficult to be sure of this - organ builders in this period jealously guarded their scaling plans in a way we find difficult to understand today.

 

In the 1830s, theorists like Toepfer proposed a new method of scaling pipes, using logarithmic scales. The standard scale was born but the majority of well-established builders (listed above), brought up in the noble tradition of organ builders passing down their skills and knowledge through the generations (and probably without the knowledge of how to wield a slide rule), did not adopt these new principals as quickly as has been suggested. Schultz and Lewis were early adopters and it tended to be the provincial builders and supply houses that seem to have been the early adopters of Toepfer's ideas, using the (slightly spurious) argument that the (supposedly) scientific principals of this scaling method were superior to the older, geometic-based, methods. Today, organs are predominately scaled to a variation of Toepfer's ideas, with the ideas of scaling to alternative methods confined to a very few small pockets.

 

If we were to compare the difference in the scalings between these 2 methods we would see something quite interesting. If we were to plot the pipes in the Toepfer standard scale as a straight line, we would see our geometrically-scale pipes whizzing off to a hugely wide scale in the extreme bass, being proportionately narrowerer in the mid-range of the keyboard (between somewhere in the tenor octave in the 8' rank and about an octave above middle c) before broadening out to be wider scale in the extreme treble.

 

As you can imagine, the problem comes if we try to combine pipes scaled from different builders with different schools of thought. Ralph Downes, with a little knowledge of Toepfer standard scales, really couldn't make head of tail of the scales employed in old contiental organs which were never designed using these principals - hence free variable scaling was invented.

 

However, consider adding a 2' rank scaled to toepfer-based logarithmic scales to a geometrically-based chorus. This is fraught with risk and danger. Even if the new rank is balenced to give the right amount of power to fit in with the pipes beneath, in some places of the keyboard the pipes will have to forced to speak very loudly compared to the other pipes on the same note and so they won't blend together comfortably - the new material will stick out. In other parts of the keyboard, the new pipes would have to quietened down and so the nature of the sound would be different again - the new material will sound muddy and indistinct. Now try playing a scale across the entire compass and see how the nature of the sound changes! Of course, at a basic level, it'll work if the regulation is OK but to someone who can objectively appreciate the difference of the sound of the choruses of different builders, the results will be horrible. This is why sticking a modern mixture made to standard modern scales from a trade supplier on top of your 1860s Hill or Walker Great principal chorus is to be discouraged.

 

So if a chorus says "it is based on a certain 8' stop" it means that the higher pitched pipes of the same family of stops are designed relate to that stop to form a homogenous chorus, as the organ builder envisaged and designed it.

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So if a chorus says "it is based on a certain 8' stop" it means that the higher pitched pipes of the same family of stops are designed relate to that stop to form a homogenous chorus, as the organ builder envisaged and designed it.

 

Thanks for all that. Obviously I do understand, vaguely, the principle behind it. You have confirmed for me that it is indeed a cut and dried matter.

 

Mind you, surely the organ builders, at least for a good part of the last century in this country, didn't expect their organs to be played in this way. Wouldn't organists have been more inclined to build up the chorus by adding 8s then 4' etc. Even in Bach.

 

I have hacked my way through a good lot of Bach in various cathedrals (playing for a visiting choir) and I wouldn't I wouldn't necessarily expect to be able to just use one 8' stop. (Although I would do so for preference if I thought the sound was right.)

 

Wasn't it a story about William Harris (I think): about to embark on a piece of Bach he pulled on all the 8 foots, paused and then saying "ah, baroque" added a 4 foot?

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I think organbuilders have always wanted their choruses to be used properly and heard to best advantage to produce the clearest and most attractive musical sounds.

 

On the organ I play most regularly, the Great Open Diapason is the strongest stop and doesn't need any reinforcement in the pleno. Therefore, I will tend to use Gt: 16.8.4.3.2.III with balencing pedal for a Bach pleno. Using the stops on one soundboard also gives the most focussed sound which aids clarity. Adding any extra 8' stops (except reeds) to this doesn't really do very much except waste wind as the grandly warm Open Diapason and harmonics thrown down from above swamps any sound they produce. This chorus is wonderful and you can play the entire Bach F major toccata on it without any stop changes, without having to worry about tiring or boring your audience. You could play it twice to them if you wish.

 

During the 20th Century in England, the pattern of the Diapason chorus evolved as extra Diapasons were added to organs in their successive rebuilds. Quite often some of the upperwork would be rescaled larger by cutting the pipes shorter and moving them a few notes up the scale. So the interrelations between the stops in the chorus was lost to the interests of dynamic variety.

 

I also occasionally play a large, very highly respected, 1950s organ where this is the case. It is a super organ which I think many traditional English organists would hold up as an exemplary organ. The Great Diapason chorus is all to do with how loud the stops are, providing enough dynamic range from being able to not swamp a halting treble solo to shouting down a full congregation with ease. It's a job to control it all. The preoccupation is the volume of the stops and adding them, not traditional chorus building. The character and sound of each of the Diapasons is all different, reached at from revoicing pipes from different sources and periods. Some would praise this organ for its great variety of Diapason colour - and indeed no 2 Diapasons sound alike on this organ and all the principals each provide yet another, individual Diapason sound.

 

But the problem is the No.2 Principal is too large and the wrong scale to work with the No.3 Diapason but it's not large enough for the No.2 Diapason. The No.1 Principal is too big for the No.2 Diapason but not large enough for the No.1 Diapason (which is made to a completely different progression). It's all to with providing different volumes of sound. The sound is always a compromise. The various rebuilds have introduced different scalings and voicing to provide this dynamic variety at the expense of blend, focus and clarity. On this type of organ I think it's fine to say "Ah, Baroque!" and reach for the octave couplers on the swell mixture to provide that much prized "brightness".

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Quite interesting postings, Colin ! thanks for that.

 

How true is the note about modern, standard Mixtures "glued"

upon ancient stops, and whose effect varies trough the compass

because the scales do not match; we have countless examples

of such missfits in Belgium.

 

Now about this:

 

"But the problem is the No.2 Principal is too large and the wrong scale to work with the No.3 Diapason but it's not large enough for the No.2 Diapason. The No.1 Principal is too big for the No.2 Diapason but not large enough for the No.1 Diapason (which is made to a completely different progression). It's all to with providing different volumes of sound. The sound is always a compromise. The various rebuilds have introduced different scalings and voicing to provide this dynamic variety at the expense of blend, focus and clarity. On this type of organ I think it's fine to say "Ah, Baroque!" and reach for the octave couplers on the swell mixture to provide that much prized "brightness".

 

From about the middle of the 18th century -and possibly even earlier in central Germany- the Diapason chorus

commenced to serve as a "backbone" to the tonal structure, and not and ensemble Sui Generis

(Save the "exception française", of course!). In organs of the 19th century, the Principal (I mean the 4'

in traditional english nomenclature) is no more scaled after the 8' Diapason alone, but for some of them

(if there are two Principals) or all of them togheter; for softer registrations with a 4', you have to use

the Flûte 4'.

Meanwhile, the Fifteenth is meant to be used with all the 8' and 4', and the Mixture(s) with the reeds

(save with exception like Lewis, who followed Schulze practice).

So the builders of such organs did not expect the Principals to be used with things like 8-4-2 2/3-2,

even if the stops were there, in order to give the organ its genuine "Principal structure". The scaling

and voicing did follow accordingly.

 

Pierre

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Yes, but how do you know? I play a fine Harrison from 1917. I wouldn't dream of using the large Open Diapason as a basis for a baroque chorus (in fact very rarely use it at all) but might Arthur Harrison have considered the chorus to based on it? I'm wondering if it's an exact science - it always seems to be stated as an incontrovertible fact, rather than an opinion, that the chorus of such and such an organ is based on, for example, the small open or the 16 foot.

 

I think you've answered your own question. I'm sure you wouldn't use a Harrison Open 1 in Baroque music, because it would sound completely out of place; in other words, you know the sound it makes and have rejected it for that purpose. As with all things musical, the answer is to listen and use what sounds right. It may not be according to someone's pet theory, and your decision may not be the same as mine, but there is no other way of deciding which stops to use with which in given circumstances - as you suggest, it isn't an exact science. And that, to my mind, is half the joy of music; in the final analysis your ideas may be different to mine, but so long as the result is musical, there is, or should be, room for both.

 

Regards to all

 

John

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In organs of the 19th century, the Principal (I mean the 4' in traditional english nomenclature) is no more scaled after the 8' Diapason alone, but for some of them (if there are two Principals) or all of them togheter; for softer registrations with a 4', you have to use

the Flûte 4'.

Meanwhile, the Fifteenth is meant to be used with all the 8' and 4', and the Mixture(s) with the reeds (save with exception like Lewis, who followed Schulze practice). So the builders of such organs did not expect the Principals to be used with things like 8-4-2 2/3-2,

even if the stops were there, in order to give the organ its genuine "Principal structure". The scaling and voicing did follow accordingly.

Interesting. Thanks for this. In my example, I can't really say this is the case. The No.2 principal is closest to the No.3 diapason in scaling (I suspect it has been rescaled at some stage) but has been loudened so it no longer forms a comfortable fellow with the No.3 and while it sings out strongly, it doesn't really blend with the No.2. It's not just a question of volume, it's also a question of treatment and compatible design.

 

From my very limited experience, I suspect that designing and voicing a 4' to work with 2x 8's is very much harder than designing it to work with 1. Firstly, the correct scaling needs to be guessed at, the sine non qua being that you correctly assess the effect of the 2 8' stops combined - this is the really difficult bit! If you can do this (and I'd be very interested to find out how you do this), then you can design the 4' accordingly - but the problem is that the 4's will be bigger than the 8's, the 2's bigger still, etc. The danger is of a top-heavy chorus...

 

In my experience, the organ builder and voicer will finish a 4' to work with its corresponding 8', then try it out with various combinations of 8' to see the effect. Usually, the situation is the voicer will go "ooo, that's nice" and may give it a few tweaks but normally won't make any serious changes. It's more a question of giving it final tweaks than designing it from the outset.

 

Most of the organs with 3 Opens/2 Principals have come to us by rebuilds so I can't imagine the design of each of the voices was there from the outset.

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Most of the organs with 3 Opens/2 Principals have come to us by rebuilds so I can't imagine the design of each of the voices was there from the outset.

 

I think Bristol Cathedral would be a notable exception to that (I was about to say Salisbury, but it's 2 of each), and it would be interesting to know how Walker's practice at Bristol differed from their treatment at Romsey, where the chorus of 1858 is based on the large Open Diapason, not the small.

 

I wonder, Colin, whether your reference to a well respected 1950s organ was St Mary's Southampton? That of course has 3 Opens, 1 Principal but a Gemshorn instead of a Flute (its greatest weakness, I think), presumably with the same aim.

 

I vaguely recall discovering that one of the stops on that organ had been replaced but can't recall whether it was that or the Gedact.

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In my experience, the organ builder and voicer will finish a 4' to work with its corresponding 8', then try it out with various combinations of 8' to see the effect. Usually, the situation is the voicer will go "ooo, that's nice" and may give it a few tweaks but normally won't make any serious changes. It's more a question of giving it final tweaks than designing it from the outset.

 

Oh dear Colin, I wonder where THAT experience lies - not with any situation I'VE ever come across I'm afraid. A voicing 'System' is useful: i.e. what you know to work. The accumulated knowledge acquired by several generations doing what you do, before you, is a great help - sadly lacking in most situations these days.

 

"Voicing" specified by a consultant - who doesn't know how to do it, has little knowledge of the historical basis on which such decisions might reasonably be made, may happen in the way you describe and, when it's a failure, who walks away from it TEFLON coated.

 

We deal in ever decreasing circles: the (basically) ignorant appointing those whom they think will gain them the greatest plaudits to build organs in place of the local firm - suddenly the local firm has gone - no work - and then what?

 

"ooo, that's nice"? You are speaking of a situation in the UK which is really pretty unsatisfactory and little to do with organbuilders - rather, Consultants.

 

David Wyld

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The accumulated knowledge acquired by several generations doing what you do, before you, is a great help - sadly lacking in most situations these days.

 

Well, it would be lacking, wouldn't it. The organbuilders of the 50s, themselves trained on fat pneumatic monsters, trained the next generation on instruments they probably didn't themselves believe in using aluminium trackers, Dexion building frames, Schwimmers, un-nicked pipes and vast quantities of chipboard. The next generation will have it easier. (I said something similar on Orgue-l with regard to why so many thousands of perfectly good tracker actions on parish organs are lamentably poorly adjusted and got shot down in flames by Ian Bell, so the reaction here will be interesting.)

 

I wonder if any firm active in the 50s, 60s and 70s routinely built instruments which the reputable firms of today would be proud to nail their nameplate to?

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I think you've answered your own question. I'm sure you wouldn't use a Harrison Open 1 in Baroque music, because it would sound completely out of place; in other words, you know the sound it makes and have rejected it for that purpose. As with all things musical, the answer is to listen and use what sounds right. It may not be according to someone's pet theory, and your decision may not be the same as mine, but there is no other way of deciding which stops to use with which in given circumstances - as you suggest, it isn't an exact science. And that, to my mind, is half the joy of music; in the final analysis your ideas may be different to mine, but so long as the result is musical, there is, or should be, room for both.

 

Regards to all

 

John

 

I wonder how Harrisons, in 1917, expected the build up to go. At what stage would the Large Open have been added. When Mark Venning from Harrisons came to hear the organ he gently castigated me for eschewing it until I had added everything else, including the swell octave coupler. He said that I should play it the way Arthur Harrison intended it to be played. (ie USE it!)

 

I know what organists in the '70s did, Pierre (that was when I was growing up), but that is a different era.

 

Another question: were any organs built before, say, 1850, or have any in the last 25 years or so, where the principal chorus is not based on the main 8' diapason/principal (or 16')?

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"I know what organists in the '70s did, Pierre (that was when I was growing up), but that is a different era."

(Quote)

 

.....And here is your own point !

Of course, they did. Fact is, an Arthur Harrison organ belongs to another era than ours.

And so, we must be able to use it as was back to its period, exactly like we would

be quite interested to know how Bach registred with the organs he had (you know,

those quite "not-baroque" things crammed with 8' tone).

Please, do not let this knowledge go now with the british organ from the beginnings

of the 20th century...

 

Of course we may try to use any organ after new ways, no doubt. But Mr Vennings

is right saying an organist who plays an H&H organ from 1917 should know how

it was used then. And if in doubt, ask him.

 

Our ways of today are exactly as questionnable as any other one, we also shall be seen

as outdated sometimes.

 

As far as I know, it is probable the custom to use the II instead of the I in anything

that may resemble what we believe today to be a "Diapason chorus" goes back to the

introduction of the leathered lips in Diapason pipes.

(Despite the fact they condemned the good Robert to the worst evils imaginable,

it seems many british builders took some of his ideas over indeed. I met with

much leathered Diapasons in the 70's. And they were used!)

 

Pierre

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He said that I should play it the way Arthur Harrison intended it to be played. (ie USE it!)

I recall Sydney Watson at Christ Church ending a Bach fugue by pulling out the No 1 OD and simultaneously pushing in everything over 4ft. Whether this was just him, or a part of an older tradition, I cannot say.

 

Paul

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Does the man not have ears to hear? I hope he didn't charge for the advice.

 

Well, I'm playing the first movement of the Elgar sonata in a concert next month and I'm going to use the Large Open for that! It does sound right.

 

I haven't yet played any Bach with it yet - even the end of a Fugue.

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