Sorry that this issue is a little late again, but circumstances made it impossible for me to get it out earlier. AK
Classical Organs, Inc. P.O. Box 27476, Phoenix, AZ 85061-7476, Tel: 877-551-7916, Fax: 602-841-1704, Email: email@example.com. You can also view the catalog: http://www.classical-devtronix.com/catalog/catalog.pdf
Ok, so I am crazy. Who would take a perfectly good Schober Organ, strip the guts out of it and rebuild it with new circuits? My problem was that I was never really happy with the operation of the keyboard but I enjoyed the quality sound produced by the Schober. There always seemed to be a chirp at the start of some notes when depressing a key. I believe that this was caused by one buss making contact before another bus due to the switching design. Also there was the ongoing contact cleaning problem, the tone generator tuning and the hiss, pops and hum that developed over the last 30 years.
When I found the Schober Orphan WEB page and read the Organ Notes article that related to the Devtronix circuits, I knew I had the answer to my problems. The beauty of the Devtronix circuit is that not only do they eliminate the tuning problem but also the attack and decay as the notes are switched and controlled electronically. Having a technical background, I decided to rebuild the tone generator section. But, of course, a DIY (do it yourself) person can't just stop there. This project mushroomed into several different phases. Like it had a mind of its own!
Phase 1 -- Design of the tone generation system.
Phase 2 -- Remove clean, rebuild and modify the keyboards.
Phase 3 -- Remove old tone generator boards, mount new tone generators and modified keyboards. Here the signals may be connected to the old audio system and tested.
Phase 4 -- Replace old audio system with new audio system designed with operational amplifiers and electronic echo.
Phase 5 -- Replace old power amplifiers and speaker system with new design. This will keep the Swell, Great and Pedal in separate amplified channels.
At this point I should have a clean switching crisp sounding Schober Organ free of chirps, pops, hiss and hum and I will never have to tune it again.
Where am I in this process? Well, phase 1 is done and I am ½ way through phase 2. I plan on describing my progress, problems encountered along the way, solutions found and results obtained. I would like to thank fellow Orphan David Casteel for the inspiration to write this. And for the record, I don't plan on deviating much from the basic Schober design philosophy, it has withstood the test of time.
(Richard has completed phase 1 and 2 and has written an article which will be in the next issues of Organ Notes)
"Just wanted to let you know that I built the photoresistor for my Schober recital preamplifier board and it fixed the problem. The entire organ is back in full working order. I thought you would like hearing that all your help was not in vain.
"By the way, I found that Radio Shack's on-line catalog had those 18 volt bi-pin light bulbs, but the milliamp rating is a little different. They might work ok, but I don't know for sure. Thanks." Ed Walbroehl
Here is my answer to the bulb question: As to the Radio Shack 18V bulb, it all depends on the brightness of the bulb, if the current draw is different from the original, you would have to replace them in pairs as two are connected in series in many circuits. I measured brightness at various voltages with a special light meter and also current draw. The bulb I specify is about identical to the original Schober in current draw and brightness. AK
I have been looking at your excellent web site for some time now and find it quite fascinating. I have delayed contacting you as I have been absolutely tied up restoring and re-installing, (with other volunteers), a nine rank, Blackett & Howden theatre pipe organ in the Coburg City hall, approx 6 miles north of Melbourne's CBD. This has been done on behalf of the Theatre Organ Society of Australia, (Victorian Division), who own two other theatre organs in Melbourne, i.e., the 3/15 Dendy Wurlitzer and a 3/17 Compton at the Malvern Town Hall. In fact, the Coburg organ which came from the Prince's Theatre North Shields, (in the north of England), was overhauled and installed in the 70s in a theatre in Reservoir, (another northern suburb) but had to be removed in 1991 because of the sale of the Cinema to developers. Therefore, Coburg was the second time around for me, (and a few others who had also worked on the earlier project). I won't dwell on this subject as it is hoped that the Coburg B&H theatre pipe organ will soon be featured in the ATOS Theatre Organ Journal, the draft article and suitable photographs having just been sent over to Vern Bickel in the States.
Now about Schober organs, at about the time the Cinema North organ was being installed I decided to build a Schober theatre model, don't ask how I managed both tasks, as well as working full time for Australia's then-only Telco. (Now privatised like everything else). Anyway I did, and everything worked out well, the organ working the first time it was switched on. I added the Percussion group, Reverbatape, (twin Channel), and put a set of Schober speakers in the console, (LSS-5 system). Not quite satisfied with that I was persuaded to then built up an LSS-10 enclosure in which was fitted 12" and 8" Wharfdale drivers, (the real ones from Gilbert Briggs not the more modern types). I also added a small Leslie unit at the LH side of the console with a switching arrangement which split off the HF side of the LSS-5 crossover network. This was not really such a good idea because of the vast difference in the efficiency of the 8" drivers, the Schober being much better than the Richard Allen used in the Leslie. However, it did colour the sound nicely and added something to the typical theatre voicing. (Unfortunately, the belt broke years ago and it hasn't yet been replaced).
Now that the Coburg pipe organ has been completed, including the essential professional regulation and tonal finishing, and then being officially opened by the Society and Council in February 2000 I find that I now have some time free, hence this letter. My Schober is still with me; despite attempts to sell it, (unsuccessful) it is like in the situation in the States, you just can't seem to give them away. The organ is currently taking up a lot of space in the dining room, and Dot and I are thinking of moving into a unit or smaller place now that the kids have gone their own way and have families of their own. So -- I have decided to put the thing back to stock standard theatre organ and get rid of the many modifications done over the years, e.g., separate preamp/vibrato boards looking after (a) the Flues, and (b) the Reeds, (another not so good idea because of phasing troubles the result of bypassing the filter board amps). A twin 50W RMS amplifier feeding the two loudspeaker systems mentioned before completes the picture. I will at least be able to get rid of the big LSS-10 system, (after recovering the Wharfdale speakers), using just the internal LSS-5 system plus, the Leslie if I can get it working properly once again.
Although the organ is now some 30 years old it has surprised me and others by causing little trouble apart from some transistor problems, and a blown rectifier quad in the Power Supply. It still fires up on switch on and even now sounds quite good, dirty key contacts excepted of course due to simply not being played enough these days. I have forgotten everything I once knew, and Dot now has arthritis in the hands making it difficult for her to play except with great difficulty. Age is wicked. Everyone here has been going "bananas" about the new Allen digital organs, which are very good I admit, BUT look at the price!! I decided recently to retrieve my old Schober demonstration LP (mono), and the Jim Ramsay (stereo) LP, which I then recorded on tape to let a few friends (most of whom aspire to Allens but have Conns), hear at first hand what Schober could do. Most were quite astonished bearing in mind the analogue technology of the 1960 and discrete construction, (doesn't everyone use "chips"?). It was actually this little exercise which prompted me to think about putting my organ back to standard again, yes the Jim Ramsay LP sounded that good although he had made some pretty drastic changes to his set up too. When I get around to doing this is anyone's guess as I seem to tire easily these days and have had some ill health as well which doesn't help.
As a matter of interest, I still have all the correspondence from Alan Tarrant, (Sydney) who was the Australasian distributor for Schober. He used to do regular trips to the States to see Richard Dorf and Bib Avendon, whether Alan is still with us today I don't know as he did have a couple of heart attacks in 1973. We really finished corresponding in late 1974, I guess after Schober's demise. Quite a large number of organs were built in Australia, Recitals, Theatre and Consolette models mainly, we even had a Schober Owners Club in Melbourne with quite a few members. Heaven knows where those people are now, (or the organs either for that matter), it is doubtful whether much follow-up could be done now, let alone if this would prove to be fruitful.
The last technical note was of interest, (on amplifier/speaker systems), and I agree with the comments made, I had the same problems with break up on loud passages and never did manage to get the Mixer/Compressor working properly so finally gave it the flick and took it out. I first suspected the speakers were the problem, (particularly the Wharfdales in the LSS-10), as it is quite well known that Hi-Fi drivers do not handle electronic organ signals all that well, despite dealing with other inputs quite adequately. Now I'm not so sure that it isn't the 50W transistor amplifiers I built since the Schober drivers in the console enclosure also break-up on loud signals, not as bad perhaps but not good either. I can see lots of fascinating work ahead!!
Well, I guess this little epistle has served to introduce myself to the group if nothing else, I don't know if you have any other Aussies involved, you may care to advise me in due course. I shall get this off via E Mail as soon as possible, Best Regards to All. Bill Worley.
Anything tube, specially for Schober tube organs for one of our members. Please contact me: Alexander Kruedener (address below).