When Closing The Organ Down After Use.

[mjgrieveson]

I apologise for asking an elementary question - I tried to do a search but somehow managed to offend the search facility and it went off in a huff.

 

What is the best way to shut down the instrument after use? All summer I have left it with the swell box open and all stops out (except the tremolo - for some reason the beast protested at this) and have had no trouble at all.

 

This week someone else played the organ (hooray) and left everything in the closed position. Result = horrible cipher (sp?) on the Great unless all stops were pulled out - obviously not an option for this Saturday's wedding.

 

The organ builder once told me that it makes no difference if the stops were left out or in.

Was this weeks blip simply due to the swell box being left closed for a couple of days? The temperature has been unremarkable.

[John Maslen]

I apologise for asking an elementary question - I tried to do a search but somehow managed to offend the search facility and it went off in a huff.

 

What is the best way to shut down the instrument after use? All summer I have left it with the swell box open and all stops out (except the tremolo - for some reason the beast protested at this) and have had no trouble at all.

 

This week someone else played the organ (hooray) and left everything in the closed position. Result = horrible cipher (sp?) on the Great unless all stops were pulled out - obviously not an option for this Saturday's wedding.

 

The organ builder once told me that it makes no difference if the stops were left out or in.

Was this weeks blip simply due to the swell box being left closed for a couple of days? The temperature has been unremarkable.

 

It all depends. If your instrument is mechanical action, leaving them drawn 'on' will in theory allow some air to circulate in the windchests, but I doubt that the effect will be very great. After all, the only opening for the air to pass through to penetrate the windchests is the gap between the lower lip of the pipe mouth and the languid - hardly a wind tunnel. If the action is not mechanical, everything will be off whatever the position of the stop controls.

 

Ciphers such as you describe are caused by dirt on the pallet, and to be frank I would think that leaving the stops 'off' would make it less likely to cause one, not more so. I suspect this was just a coincidence.

 

Leaving the Swell box open is usually advised as it allows the internal temperature of the box to be the same as the unenclosed sections, avoiding tuning problems.

 

The main reason for leaving all stops 'off' is to avoid embarassment when switching on, just in case something is touching the keys ...

 

Regards to all

 

John

[basdav]

Why have a General Cancel if the stops are being left out? The Swell Box should always be left open when switching the organ off to avoid tuning problems as John has indicated.

[mjgrieveson]

Why have a General Cancel if the stops are being left out?

 

I really have not the first idea how the organ works 'round the back' which is why I have to ask the silly question; I use the General Cancel between pieces to make sure I haven't left out something like the cornopaean by mistake thereby frightening the horses (and myself) if the next item is supposed to be pp.

 

I somehow imagined that I might be letting air and ventilation (generally considered A Good Thing) through by leaving the stops open, although the clunking sound that follows switching off caused me to wonder whether it made any difference.

 

I am grateful for replies - I have yet to find out what condition the instrument will be in this evening - I just hope that a day or two with the swell box open will have rectified the fault because I don't know how to tackle dirt on the pallet without calling in the cavalry.

[ajsphead]

The clunk you can hear is probably the drawstop machines or solenoids returning when the current is switched off. Therefore the stops are off with the current off, so there's no point leaving the drawstops out. Even with mechanical drawstop action, the benefits are minimal, and probably outweighed by the potential for letting dirt and small creatures into the soundboard. Cleaning dirt off the pallet, resetting the pallet spring, or adjusting/cleaning the pallet guide pins is easiest done with specific tools, so if it continues, call your organ builder to do it.

 

AJS

[MichaelDavidson]

The Swell Box should always be left open when switching the organ off to avoid tuning problems as John has indicated.

 

One some instruments even this isn't possible. I can think of at least one electro-pneumatic instrument which had horizontal swell shutters that were not balanced and which closed whenever the instrument was turned off. If you left the swell pedals in the "open" position when turning the instrument off all that happened was that you were rewarded with an almighty crashing sound as all three swell boxes slammed shut ...

[notebasher]

One some instruments even this isn't possible. I can think of at least one electro-pneumatic instrument which had horizontal swell shutters that were not balanced and which closed whenever the instrument was turned off. If you left the swell pedals in the "open" position when turning the instrument off all that happened was that you were rewarded with an almighty crashing sound as all three swell boxes slammed shut ...

 

Yes I recall that some (more-or less) totally enclosed Comptons do this; all the swell boxes close when they are switched off. I understand that because all the pipes apart from some basses are treated the same way there aren't any issues with tuning but the pipework remains cleaner. Even so on 'normal' organs I leave the boxes open for the reasons John explained.

 

R.

[JWAnderson]

One some instruments even this isn't possible. I can think of at least one electro-pneumatic instrument which had horizontal swell shutters that were not balanced and which closed whenever the instrument was turned off. If you left the swell pedals in the "open" position when turning the instrument off all that happened was that you were rewarded with an almighty crashing sound as all three swell boxes slammed shut ...

 

One way of getting around this if the instrument has vertical shutters would be to have a piece of rope or cord attached at one end to a reservoir and the other attached to the shutter rod, this would mean when the organ is turned off, the EPn shutter motor will still close the shutters like it normally would, but as the reservoir deflates it will pull the shutters back open slightly. However I don't know if this solution could work on horizontal shutters (maybe if they are balanced).

 

JA

[CTT]

One way of getting around this if the instrument has vertical shutters would be to have a piece of rope or cord attached at one end to a reservoir and the other attached to the shutter rod, this would mean when the organ is turned off, the EPn shutter motor will still close the shutters like it normally would, but as the reservoir deflates it will pull the shutters back open slightly. However I don't know if this solution could work on horizontal shutters (maybe if they are balanced).

 

JA

It works with horizontal shutters also. Just have the cord running up and over a pulley to the cock rod on the shutters, and as the reservoir deflates, the cord gets pulled around the pulley and hey presto, an open swell box.

(Of course there is one distinct disadvantage to leaving the swell box open. When some [insert expletive here :angry: ] tries to burn the church building down and the heat blast hits the wonderful 1905 Hill 3M , the heat melts the tops of all the bass pipes in the open swell box. But if the box is left closed, as the choir box was, the pipework remains safe from waves of superheated air.)

[mjgrieveson]

Thank goodness there was silence and serenity when I gingerly pulled out a couple of stops last evening, only a faint whisper of a whistle after 90 minutes hard work and an experimental closing cadence that I decided, on reflection, was too loud anyway.

 

Fingers crossed for an uneventful wedding this afternoon.

 

I think we are in more peril from small creatures (hadn't thought of that one :angry: ) than vandals despite being an UPA but I'll continue to leave the swell box open and stick a post-it note up to remind anyone else to do the same. Interesting idea about the rope pulling open the swell as the thingy goes down. Clearly, the clunk indicates a major shut down regardless of whatever I do with the stops.

[John Maslen]

Reading the sad tale of a fire damaged Organ reminds me that on Wurlitzer theatre Organs the Swell boxes always close when the instrument is off because of fire regulations. I wonder if the reported behaviour of the Compton is based on the same idea; they built quit e few theatre and cinema Organs in the early days.

 

Regards to all

 

John

[JWAnderson]

(Of course there is one distinct disadvantage to leaving the swell box open.)

 

Two if you count dust from building works being spread throughout the organ.

 

JA

[CTT]

Two if you count dust from building works being spread throughout the organ.

 

JA

And all join in in the chorus, "And it all makes work for the working man to do...."

[CTT]

The clunk you can hear is probably the drawstop machines or solenoids returning when the current is switched off. Therefore the stops are off with the current off, so there's no point leaving the drawstops out. Even with mechanical drawstop action, the benefits are minimal, and probably outweighed by the potential for letting dirt and small creatures into the soundboard. Cleaning dirt off the pallet, resetting the pallet spring, or adjusting/cleaning the pallet guide pins is easiest done with specific tools, so if it continues, call your organ builder to do it.

 

AJS

The clunking noise could also be from the reservoir collapsing rather faster than it should if there is no non-return valve attached to the blower, or similar flap inside the trunking from the blower to the reservoir.

[Andy]

Reading the sad tale of a fire damaged Organ reminds me that on Wurlitzer theatre Organs the Swell boxes always close when the instrument is off because of fire regulations. I wonder if the reported behaviour of the Compton is based on the same idea; they built quit e few theatre and cinema Organs in the early days.

 

Regards to all

 

John

 

Although presumably that's to prevent a fire that may start in the organ from spreading out to the theatre. It may have happened once. Old fire regs are usually a (knee-jerk) reaction to a previous fire.

 

Andrew

[Stephen Dutfield]

Although presumably that's to prevent a fire that may start in the organ from spreading out to the theatre. It may have happened once. Old fire regs are usually a (knee-jerk) reaction to a previous fire.

 

Andrew

 

Actually it's a lot simpler than that! The fire protection is just a happy by-product of the fact that theatre organ shutters are sprung shut and, as the organs are totally enclosed, there's no requirement for leaving them open, they simply close when there's no longer any wind to keep them open. In any case it is far easier to keep the tuning of a theatre organ stable by having thermostaically controlled chamber heating. With shutters closed most of the time in a 24-hour period, the varying temeraptures in the auditorium can be kept at bay. Even so, most theatre organs in major theatres in the 1930s were tuned once a month, and additionally if there were broadcasts.

 

There was an interesting varient of the fire protection which I saw in many London-area theatres (so it may well have been a requirement of the old LCC) which used a thermal coupling in a wire running through each chamber. One end was anchored, the other end was attached to a heavy metal shutter in the outside wall which, when dropped would open a smoke outlet to the outside. Also in the system was a contact block through which the -15v return from the shutters passed. The circuit was made by a knife-edge contact on a peg which was also attached to the fire shutter system. Should a fire have broken out in the chamber while the organ was playing, the heat would melt the thermal coupling, allowing the weight of the fire shutter to drop. As the shutter opened it also pulled on the cable attached to the peg, which flew out of the contact block, breaking the return from the shutter action and closing the swell shutters.

 

Although an ingenious system, I have never heard of it actually working 'in anger' and, as far as I know, the few theatre organs in this country lost in fires were destroyed as a result of a fire breaking out in the theatre itself, not the organ chamber.

 

S

[John Maslen]

Although presumably that's to prevent a fire that may start in the organ from spreading out to the theatre. It may have happened once. Old fire regs are usually a (knee-jerk) reaction to a previous fire.

 

Andrew

 

I'm quite sure that's why, although whether or not it was the result of a fire I don't know.

 

Regards to all

 

John