Schober Organ Notes No. 79

OVERTURE

Disclaimer: We accept no responsibility for any unfavorable consequences resulting from following our advice

OVERTURE

It seems as though issue 78 was just mailed out, yet here it is time for another issue. Please note that I skipped parts of Ken Stone's emails. Those parts refer to the REVERBATAPE and I extracted them for the Reverbatape article in issue 78. I hope that you all have a great summer. AK

REVERBATAPE TAPE HEADS AVAILABLE

Our member Jim Sands placed an ad in ON77 asking where tape heads for the Reverbatape could be obtained. Since then I have done some research on the subject and found the Schober spec. sheets and sources for them. (To e-mail text subscribers and web readers: The above chart will not print. If you are interested in it, I will send you a printed copy of ON79 as well as a copy of the original Schober spec. sheets. Please send me a SASE with $.60 postage and an extra stamp.)

When Nortronics went out of business, Joe Dundovic bought out their stock and has the above Nortronics heads for sale. He explained to me that an "H" in the parts number indicates half track. So, Schober used half track heads. Joe said that the half track erase head is fine for use as intended with the half track record and playback heads. The section of the part number after the dash indicates the special Schober side mount. Joe has these special heads.

You can reach Joe Dundovic at: jodun@usinternet.com, he has a web site: www.magneticheadstockroom.com, his address is: Magnetic Head Stockroom, 1701 Rhode Island Ave. N, Minneapolis, MN 55427. Phone: 763-545-7538, Fax 763-545-9269.

Another source is: John French of JFR Magnetic Sciences in New Jersey. I was hoping he would get back to me before this edition of ON was printed. His telephone number is: 973-579-5773. If I get additional information, I will publish it in ON80. He has a very interesting web site: www.jfrmagnetics.com, with articles on tape heads, etc.

I advertised in Antique Radio Classified to find a source for tape heads. The above sources were given to me in response to that ad. In addition I was also given the following web site: www.michiganmagnetics.com. I got on that site but it's useless. They give a contact e-mail address (info@michiganmagnetics.com). I asked them about the above Michigan tape heads but received no reply.

www.recordist.com/ampex was another internet site recommended, but I can't get up on it.

SOME MORE ON THE ENDLESS LOOP REVERBATAPE CONVERSION

Actually, there will be some more in the next issue. I made the conversion and some changes to it. I'll publish some photos and information next time. AK

CLASSICAL ORGAN-DEVTRONIX (Mark Voorhees)

One of our members was trying to get an update to their catalog but was not getting a response to his e-mail. I phoned them and they are still in business. Their e-mail address is: info@classical-devtronix.com Phone: 602-973-1395.

KEN STONE'S EMAIL #1

Hi Alex, I have finally purchased a Schober Theatre. With it came most if not all of it's documentation, as well as personal mail from the Australian Schober rep, club newsletters from the Australian Schober Club, various articles of interest to organ builders, etc.

I hope to share various bits and pieces of interest. I have scanned the cover of a local electronics magazine, featuring the Theater organ, and uploaded it to the yahoo discussion group. Below is some of what was said about transistors in the private letters. Hopefully it will be of some use to other Schober orphans. -- Ken

The following are excerpts from letters from R.A.B. Tarrant, the Australian Rep for Schober, and the constructor of my Theatre organ. They deal mainly with the subject of transistors, and the lack of quality of some of the original transistors. Of course, both transistor prices and transistor technology have changed significantly since then, so we are in a good position to do something about it. The most obvious thing from the following is that the 046127 transistors were used because they were cheap, not because they were good, which they weren't.

Possible substitutes suggested for the 046127 and 046127R alike are: 2N2614 AY1115

My organ has many of the Australian made AY1115 in place of 046127 throughout the organ. -- Ken

1st extract:

Please be forewarned that all your bothers are not yet over with instability of oscillators. When you have had the organ going for a few hours you will find that one of the generators here and there goes sour. However, after about twenty hours of running, you will never again have to touch the generator boards. So, be prepared for this annoyance. When one uses bottom-of-the-barrel transistors which the 046127 is, one has to pay some sort of a price. It is a rough way of doing things, seemingly, but it works out very well in the long run. All that could be achieved, possibly by using the very best transistors available would be a slightly higher output voltage -- and that simply is not worth the extra cost (ten times what the 046127's cost, and a bit more at that).

2nd extract:

Before starting to detail what I would like you to do, I must hasten to say that my own Theatre Organ (soon to leave me -- more on that later) is quite acceptable to me-- and I'm a real fusspot. Unless you listen intently for background noise, you just can't detect it.... I think I have mentioned what I have done which is all I've done, at that-- absolutely nothing else); this was to put six 2N2614 transistors in the stop filters and another two in the preamplifier/vibrato. Eight transistors shut the noise up to my complete satisfaction. (Those 2N2614's are expensive, and I've got on to another type which is a third of the price -- 66c each -- made in Australia and which do an even better job).

Now to the tests. First, I would like you to disconnect the mixer-compressor. This was always a thorn in my side, and I will say more on that, too. Also, take the RV-3A Reverbatape Unit out of circuit. What you do now is to take the output from your preamplifier-vibrato circuit straight to your amplifier -- no mixer and no Reverbatape to add any noise. How is the noise now? It ought to be quite quiet. If there is some noise, and you would like less of it, I will supply transistors for the stop filter section. (You could use Schober 046127R -- the red caps, but these are a pretty vague old lot, although Schober state that they have been specially selected for low noise and low leakage. I think them just the best of a bad bunch, to be truthful, and not quite good enough for these noise-sensitive sections). Now, put the Reverbatape back in between the output of the PTR and the input to the TR-2 amplifier. Has the RV-3A (or is yours an W-3?) added a significant amount of noise? If so, then we will send down another three transistors for it.

All this has been started by a couple of owners down your way being quite unhappy about the noise level, and I did not realize just how bad it was to a purist -- and both of these owners are demanding in this regard -- as they are entitled to be. Which brings me back to where I started: you, too; might want a much more silent instrument than you have, and I want you to be absolutely 100% happy with the noise position. Others can get along quite cheerfully with it; others can't. We have, to be sure, supplied plenty of Theatre Model owners, all over Australia, with tested 046127R's galore, and have got them happy, but ----- as I have intimated ----- that type is not good enough for absolute silence, hence my wanting to provide a really good transistor which will do the job. Back over to you on this one.

3rd extract:

Regarding the AY1115's, these go in any place that you have a Schober 046127 or 046127R. Try these in positions 5, 114 and 118 in the RV3-A; try them in the STF section -- pulling out all the six 046127's you have there; try them in the MTC in all positions. You should get a noticeable reduction in noise, and bring it down to minimum -- or nearly. Also, with the 17 x AY1115's, I have sent you 11 specially-tested 046127's for your PTR section. (You have the old PTR-4; don't you?). Try these as replacements for the whole complement in that part. You could, of course, use AY1115's in the PTR-4 but those I am sending down are a bit special -- Bob Avedon, Schober's Chief Engineer, has personally verified the lot.

KEN-S EMAIL #2

Dear Alex, Here are some more rambling for use in Organ Notes, assuming you consider them of value. Again I have extracted info from old material, adding comments where appropriate. Some of it covers well know issues, while some of it I have not seen mentioned elsewhere. There is also a brief info about my organs. Cheers, -- Ken

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Recently I purchased three Schober organs - a Recital, a Consolette II, and a Theatre. While I have been looking for a Schober for some time it was not until very recently that I found any. While it was the Theatre I was looking for, I bought each of them as I found them.

The Recital was in truly horrendous condition as it had been left out in the weather, and was eventually parted out. It's Reverbatape, while rusty, proved to be in good enough condition to persist with.

The Consolette II had never been completed, and is currently forming the basis for a four keyboard unit. It was great fun to receive some of its modules still in kit form. The original owner was from PNG, and that was to where the kits were shipped. According to what I've read, various parts of this organ were destroyed in transit, leading to much frustration while replacements were sourced. The Reverbatape never performed to the owner's satisfaction and was discarded. An electronics magazine spring-reverb was placed into the console, but never wired in.

The Theatre had belonged to the former president of the now defunct Schober Organ Club of Melbourne, Australia, and was a showcase organ at one point, being the organ used at the first Australian get-together that eventually led to the formation of the club. This organ came with the LS10a speaker, a home made pipe speaker (12 tuned pipes), a home made Leslie, and a Roland Revo 30. It had not been powered in at least 10 years, and all mains wiring was perished. It is in excellent cosmetic condition, and I am currently rebuilding the parts of it that need to be, before I can apply power. The Reverbatape had been disconnected. You will find comments about its (poor) condition below. With the latter two organs, I received a lot of the original correspondence between the owners and Schober Organs (Australia), and the original documentation. With the Theatre, I also received club newsletters, extra documentation, related magazine articles and so on. From these I am sharing a few interesting suggestions and comments.

-- Ken (I deleted pertinent information about the REVERBATAPE from this letter since I published excerpts about it in issue 78. AK)

And finally R.A.B. Tarrant's comment on the Mixer compressor (which amused me somewhat).

You mention having the mixer MRCC-1 -- although our sheets show you as having been supplied with a MRCC-2. (The MRCC-I, of course, has that lousy compressor thing in it; never was worth two cents as an idea or in practice: I felt it degraded the organ's tones, in fact). What one do you have? Ken: Alas despite the invoice being for the MRCC-2, the MRCC-1 was supplied. It was not in circuit when I received the Consolette II. As for the MRCC-1 in the Theatre, the compressor parts were not installed, and the PCB was hacked down to about half of its original length.

Ken Stone

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Recital Available in San Jose, CA.

Make an offer for a fine late model Recital. Contact: Harlee Carter 408-205-3622 harlee@sbcglobal.net

Schober Organ available.

In Corona, New York, Schober organ case with components, a Concert. "If you're interested in restoring this fine instrument, my phone number is 718-335-6589. Lizcomp@aol.com"

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Editor: Alexander Kruedener, 161 East 89 Street, Apt. 4E, New York, NY 10128, (212) 831-0662. Kruedener@juno.com

ORGAN NOTES FOR SCHOBER ORPHANS AND FRIENDS Issue #79
Fred Henn Founder & Headmaster Emeritus
June 2003
EDITOR Alex Kruedener kruedener@juno.com
FORMATTING Bill Kohrumel bk3@usmo.com
EMAIL Jack D. Gildar JDgildar@juno.com
Schober Organ Orphans' Page: http://www.users.cloud9.net/~pastark/schober.html