my new-to-me Allen 1203: submarine pinging and rattly Posaune

[efkeebler]

Hello, everyone! First, a hearty "thank you" for all the wonderful information on this site. I've been lurking for a while now, reading lots of informative and entertaining threads; and today I'm making my first post in the hope that some of you who are wise in the ways of the inner workings of Allen MOS-1 organs, can help me banish the last few bugs from my new (to me) instrument.
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The instrument is an Allen 1203-3DKC, which I discovered on craigslist. A church in Washington, DC was giving it away to make more space for their praise-band setup, and I was fortunate enough to be the first person to present them with a realistic plan for its removal (apparently one woman had asked if the organ would fit in the trunk of her Toyota). After roughly eight trips in my little pickup truck between DC and Wilmington, Delaware (including the final terrifying ride with the sizeable and decidedly front-heavy console), and the installation of a wider front door on my house, I now have the organ itself, two racks of amps, and 19 speaker cabinets all in place. I'm currently listening with headphones connected to a mixer and reverb unit, and hope to run wires to the amps and speakers soon. Here it is (along with my assistant, who helpfully tickles my legs with his whiskers while I play and occasionally leaves a tennis ball on the bench foot-rest):</p>

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Fortunately, as someone who makes electric instruments for a living, I have decent skills with a soldering iron and multimeter, and I've already repaired several electrical problems. (I've also adjusted the manuals so that the depth of touch and point of speech now conform to AGO specs... the keys had been travelling around 1/2" and were speaking way down at the bottom, which felt awful.) However, I have two issues that remain, the causes of which I have not yet been able to locate. I've already re-seated all the connectors on the edges of the cards to rule out dirty or corroded connections, with no result. (I'll consult an Allen-authorized repair establishment if necessary, but I'd rather make the repairs myself to save money and to learn more about how this beast works.)</p>

The first issue is an occasional "submarine ping". This is a stereo, four-computer instrument, and the problem seems to be emanating from just one of the two Great/Choir computers (the other two are the Swell/Pedal computers). The sound of the stops generated by the offending computer, will suddenly drop out, and an incredibly loud ping (generally pitched at high B) will sound, sometimes accompanied by digital-sounding crackling static. After this, normal functionality resumes. Sometimes this occurs immediately when first turning the organ on, but it often happens at random times, and sometimes it pings several times in succession. (Perhaps it's looking for other organs in the neighborhood?) The noise sounds at "full organ" volume, so it can be quite startling, and I'm hoping to fix this issue before connecting the speakers!
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The second issue is an occasional digital noise in one channel of the 16' Posaune in the Pedal division. (It's stereo, and one side plays the fundamental pitch while the other side plays an octave higher; the noise happens in the fundamental-pitch channel.) The strange thing is that it reminds me somewhat of a "real" dirty reed! I haven't noticed this problem in any other stop on the organ. Like the pinging, this noise comes and goes with no obvious cause, and drives me nuts.
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Any suggestions would be much appreciated! [H]
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[OrgansR4Me]

Re: my new-to-me Allen 1203: submarine pinging and rattly Posaune



Thanks for sharing the great photo. Makes the rest of us wish we owned trucks. I'm fortunate to have two or three friends with pickups but have never had the nerve to ask them to do a console with me. I purchased a smaller two manual Allen Computer organ and while I haven't been able to get to the real reconditioning of the instrument that I intended when I made the purchase, at just the time I relegated it to my work area from the front room because some voicings were going in and out intermittently, I found quite by chance that many oddities can relate to the alignment of the magnetic contacts in the pedal board.</P>


To explain, though some flute voices went out intermittently in the front room, on first trial in its new location the organ didn't play at all? What have I done, said I with thoughts of the $900 investment I had in the old gal. After several failed attempts for some reason I pulled the pedalboard -- which I only suspected because it had been the creator of the terrible cipher that caused the Music Store owner to let it go so cheaply -- and when reseated the whole organ was on again. (Can't bring anyone up to date on the organ since it hasn't been powered again after settling in it's new location.) It has become the second home to some of my kitties who love to hide under the sheets, tablecloths, and quilts protecting the organ while stored. They keep one bowl of food on the floor at one end and on the top deck at the other. Only causes problems when 3 want to eat at the same time.</P>


It's an easy fix worth a few minutes of your time and you have nothing else to lose. Best wishes on your restoration. Did you ask the church if they had any experience with problems before its retirement, by the way?</P>

[Tony Pipe Milwaukee]

Re: my new-to-me Allen 1203: submarine pinging and rattly Posaune



Man, when there is a will there is a way!</P>


My 15 year old daughter and I just moved our Allen 301-c to our house. We did have help picking it up. We slid in on it's back into the back of our mini-van. It fit perfectly, much to the surprise of the person we got the organ from.</P>


When we got home that's where all the fun began. We loaded the organ out of the van and got it up 8 steps by ourselves into the house. I now know how the Egyptians built the pyramids! When there is a will there is a way! I know that this organ is a miracle blessing because I've prayed for one for years and I'm sure the angels were helping us too!</P>


Tony</P>

[jbird604]

Re: my new-to-me Allen 1203: submarine pinging and rattly Posaune



keebler,</P>


What an awesome-looking console! And that would be about as good as MOS-1 ever got, with four complete computer systems, so you have a totally independent Swell (sharing with the pedals, but still making use of all the available manual resources in the computers). It comes with some of the unfortunate artifacts of MOS-1, but one that large overcomes many of the problems with its huge resources and separate sound systems.</P>


My first thought -- regarding both the problems noted --is that you have one computer board operating marginally. Have you checked to make sure that all the power supplies that are supposed to put out -27 volts are set to -27 or possibly even -28? Especially whichever one of those is being used to charge the batteries for the capture action (if this one has sequential capture) -- that one may have to be set at -28.5 for the system to work reliably.</P>


If you have a later model with DM capture, the -27 supplies are not charging any batteries, so I would set them at 27.5 volts and leave it at that. However, for trouble-shooting purposes you can vary the voltage of each supply up or down by about 2 volts ( from -25 up to -29). If one of the boards is particularly sensitive to voltage swings, it will surely "complain" loudly when you take its voltage that far off spec.</P>


If the "complaint" you hear from one of the MOS boards sounds just like the "ping" you are getting right now, then you have located the offending board. You can try setting the voltage perhaps 1.5 volts higher or lower than -27 just to see if it will make the board work reliably. If not, your only choice is to have it sent in to Allen for repair by your local dealer or tech. That will cost you several hundred dollars, but then, you don't have much money in this organ yet!</P>


Another procedure to try is putting a very light coat of Vaseline on the card-edge connectors of each and every board in the system. You say you've already re-seated them, but pulling them off and putting on the light coat of Vaseline insures that all the connections are making good contact. </P>


Yes I know that Vaseline is notan electrical conductor, but it banishes corrosion from the gold and copper surfaces and allows a much improved electrical connection. Believe me, it works. I've done this to scores of MOS-1 Allens and it is a good idea for any organ with plug-in boards. I highly recommend doing this to EVERY electrical point of connection in the organ, audio connectors, power supply fanning strips, etc.</P>


You also need to thoroughly clean and possibly even apply Vaseline to the drawknob switch contacts, if they are open-air. I don't remember if the knobs on this model are open-air or if they are reed swtiches. Reed switches don't need any maintenance, of course, but they can be out of adjustment so that the reed is not closing every time.</P>


Hope something here helps a bit. Let us know how it turns out.</P>


John</P>
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[arie v]

Re: my new-to-me Allen 1203: submarine pinging and rattly Posaune



John,</p>

Of late in servicing older organs, I find bad connections at connectors and IC sockets to be a principal cause of breakdowns in organs. Most of the organs I refer to are from the 80s and back further into the 70s. Also, I am finding a fair number of cold solder joints as well. Sometimes I come across organs that behave so wierdly, it is hard to deduce what or where the problem is coming from. You start wiggling the boards, and connectors and the problem goes away. When this happens you never know if you really got the problem sorted out long term.</p>

How exciting it is to service organs.</p>

AV</p>

P.S. I find electronic part failure to be a relative rare occurrence, except from lightning strikes, line spikes, etc. Most components on organs I replace are switches, pots, speaker drivers, lamps, batteries, key contacts, fuses, etc.
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[jbird604]

Re: my new-to-me Allen 1203: submarine pinging and rattly Posaune



Arie,</P>


Same experiences here. Amazing how reliable the old electronic parts are, but that corrosion and dirt sure can get in the way! That's why we do the full tear-down and Vaseline job on just about every older organ we service now.</P>


Is it still winter up there? Sure is hot here today (already at 7 a.m.)</P>


John</P>

[nullogik]

Re: my new-to-me Allen 1203: submarine pinging and rattly Posaune

[quote user="jbird604"]

Arie,</p>


Same experiences here. Amazing how reliable the old electronic parts are, but that corrosion and dirt sure can get in the way! That's why we do the full tear-down and Vaseline job on just about every older organ we service now.</p>



John</p>

[/quote]</p>

Jbird, thats one heck of a MOS instrument that guy has got, and for free! I only wish I lived in the US and had seen that ad, otherwise that would be mine.[:P]Then again, the amount of times I've said that about various Allens that have popped up for sale, I would have a collection to rival the Allen museum!
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You don't see many MOS1 instruments of that size around so he's got a real gem of an organ there.</p>

Interesting to read about how hardy these old electronic parts are. Bearing in mind that these things were in their infancy back then one would expect these parts to be a bit ropey, especially as they age. Its a real credit to the original engineers at Allen OC and Rockwell that these organs are still going strong to this very day with relatively few serious faults. </p>

With all this lead-free solder lark, one wonders how well the latest range of digital organs will hold up in say, 20-30 years time?...regardless of brand.
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[cpv]

Re: my new-to-me Allen 1203: submarine pinging and rattly Posaune



efkeebler,</P>


Wow, congratulations on such a beautiful organ! The photo presented a sad juxtaposition of the state of worship music today, in my book. Call me old-fashioned, I guess.</P>


Wish I woulda thought about the wider front door, instead of letting my husband take a sawzall to our door frame when we brought our organ home.....[:(]</P>


Good luck</P>


cpv</P>

[efkeebler]

Re: my new-to-me Allen 1203: submarine pinging and rattly Posaune

Thanks to everyone for the tips! </p>

OrgansR4Me: I hadn't thought to try removing and reseating the pedalboard. In this case it didn't fix the problem, but while I had the pedalboard off, I figured out how to adjust the depth at which the pedals speak, which is a big help as that was out of alignment just as the manuals were.</p>

Tony Milwaukee: yup, it's all about having the will to get the job done! Steps are the worst to deal with... in my case I ended up hiring professional piano/organ movers just to get the instrument out of the church and into my truck, mostly due to the stairs at the front of the church coming down from the raised area where the console was located. Aside from that, I relied on the generous assistance of lots of friends to help with the removal of the 19 heavy and awkward speaker cabinets from the church attic spaces, and with the unloading of the instrument from my truck onto my front porch. I too was lucky in having the console JUST fit into my vehicle:
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cpv: that photo in my original post is actually my living room, not the church where the
organ came from; but I assure you that the setup in the church was
quite similar... the organ looked so sad, pushed off to one side and unused. When
I first examined the console in person, the people who were showing it
to me thought it might not work at all since they got no sound when
they turned on the power switch and pressed some keys... turns out the
swell pedals were both in the closed position - that's the kind of easy
fix that I really like. [;)]
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jbird604: I very much appreciate the detailed diagnostic tips you provided! Alas, none of the voltage adjustments you recommended made a difference in this case; but I never would have thought of the Vaseline trick, which actually makes a lot of sense and which I'm sure will save me headaches down the road. And while I was making the adjustments and digging around in the console, I figured out some important stuff: </p>

First, I hadn't been aware that there are treble and bass controls for the various outputs. They're small trim-pots located on the DAC cards, and they were turned down so far that the instrument sounded a bit bland... what a wonderful moment when I turned them all the way up and heard just how bright and full this organ can sound! I'm now doing all my EQing with the external mixer I'm running the instrument through at the moment.</p>

Second, I've figured out that each of the two problems I mentioned in my original post, is being caused by a faulty MOS board (one board per problem, ugh). Fortunately they're not the two more complex "8" boards with the small MOS modifier boards attached, but rather the simpler "88" boards. I figured this out by turning the various boards on and off with the helpfully-provided power switches inside the console, and also by carefully swapping around various identical boards to rule them out as being the cause of the problems. Once I could transfer the "submarine ping" effect from the great/choir to the swell/pedal just by moving the offending MOS board, I knew I'd pinpointed the source of that problem. I tried touching up a few suspicious-looking solder joints, but nothing I did seemed to make any difference, and since I don't have the schematics for this board it looks like I'll have to replace it. As for the rattly Posaune, it turns out that both the 8 and the 88 MOS boards should be sending out the full range of partials, but the 88 board occasionally loses the fundamental tone, and when it's coming in or out it creates the rattling noise. I re-heated over a thousand solder joints on the back of this board, hoping that there was simply a loose lead somewhere... but no luck, aargh! This board was stamped with a date in 1980 (two years after the instrument was made) and was clearly a worked-on pull from somewhere else, with plenty of evidence that ICs had been removed and replaced. Strangely, one pin of one IC had been removed from its solder-joint and bent to the side, apparently on purpose - I'm not sure what's going on there, as the other similar board hasn't been modified in this way.
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Thanks again for the suggestions! I've learned quite a bit about how the organ works and it sounds much better with the treble and bass turned back up; plus I'm sure I'll save a bit of money in the long run by having figured out the locations of the problems myself and by just ordering the necessary MOS boards instead of having a technician bill for lots of hours of travel time and labor.
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-Eric.</p>

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p.s. When ordering replacement MOS boards through an Allen dealer, does one receive brand-new boards, or are they all factory-reconditioned?
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[arie v]

Re: my new-to-me Allen 1203: submarine pinging and rattly Posaune



Eric,</p>

My understanding with Allen is that for MOS-1 boards, they have a number of repaired ones sitting on the shelf ready to be shipped. The dealer or their authorized techs will have one or more refurbished boards on hand for replacement. When Allen ships a board out, they want the faulty one back for repair and it goes back into stock. I also understand that the early MOS-1 computer boards, were fairly early on replaced with better boards, and Allen was also making available better DAC boards for the early MOS-1 organs. In other words the early organs could be made to sound somewhat better via an expensive repair job. </p>

I don't know how much call there is these days for repair of MOS-1 computer boards. Seems of late an awful lot of the first generation digitals from Allen have been replaced, just tossed, or gutted and used as a console for Hauptwerk or some other virtual organ program.</p>

Arie V
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[efkeebler]

Re: my new-to-me Allen 1203: submarine pinging and rattly Posaune



Hmmm, very interesting! Hopefully my 1978 instrument has the improved version of the MOS boards already... I suspect that replacing the two defective boards is going to be expensive enough, without the temptation of a "new and improved" version of the other two as well. [:P] I think my DAC cards say "DAC III" on them.
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Another question: there's a blank stop knob at the bottom of the pedal division, and a blank rocker tab in the row of couplers above the manuals. Was this a way to encourage people to buy upgrades of some sort? I'd sure love to have a 32' pedal reed... [:D]
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[cpv]

Re: my new-to-me Allen 1203: submarine pinging and rattly Posaune

Oookay....where do you sit in your living room?![;)] Best of luck with your project!

[efkeebler]

Re: my new-to-me Allen 1203: submarine pinging and rattly Posaune

Heh heh... well, the room is actually considerably longer than it appears in the picture - there's also an area with a sofa and coffee table. But yes, overall I do prioritize my use of space according to what's most important to me! [8-|]