My Lowrey Heritage Deluxe DSO-1 Restoration
After many years of coveting the mighty Heritage Deluxe DSO-1 made famous by the likes of Alan Haven, Harry Stoneham and Rory More, I was offered one in need of considerable work.
It had spent much of its life in a Manchester working men's club before being rescued 10 years ago. At this point only the lower manual worked. It then spent 10 years in dry storage before I picked it up in January. As you can see in the first of the pictures, it had some cosmetic issues to say the least. Electronically it was very quiet and none of the features worked.
The first hurdle was to rebuild the power supply and due to the lack of space on the chassis, I opted to "re-stuff" the can capacitors with modern Panasonic discreet capacitors. This also preserved the look of the generator tray which to me is important on an instrument of this importance. The power supply had previously been re-capped with some maroon capacitors which can be seen in the early generator pictures. These were all removed to preserve the appearance. At this point I also found a few disconnected wires which I put back in their rightful place.
I now had most of the non-sustaining voices ie 16' and Quint working on the upper manual and all of the 8' and 4' on the lower manual. The keying of the sustaining voices (8'/4'/2') is achieved with firing neons aka the NE23. These reside on the generator tray next to each oscillator/divider circuit of which there are 12. Sometimes these neons snap off as their legs become brittle and in this case I could hear the tinkle of neons hitting the floor every time I opened the back of the organ. I decided to grasp the nettle and replace every single one. There are 19-20 for each of the 12 notes if you include the pedal keyer! I had been fortunate to grab over a thousand of the modern replacement neons when I had the chance.
Now I had all of my upper and lower tones working but still no pedals. There is a lot written on the web about "Lowrey pedal burble" I don't subscribe to the theory of moisture and humidity causing pedal issues. What I know for a fact is that the various busbars on the pedal switch assembly must have specific dc voltages for keying and cancellation (muting). Every time I tackle a pedal problem on a valve Lowrey I replace all of the voltage divider resistors, clean the contacts and busbars and reflow EVERY solder joint - remember these have taken a pounding over the years! The result is a solid, burble free pedal manual.
Ok. So now the pedals and manuals are all playing nicely so what next? Couplers and AOC. These were not working properly and the culprit was our old friend the NE23 neon again. There are two more sets of neons behind the lower manual that handle upper to lower coupling (so that you can play upper manual sustaining voices on the lower manual) and AOC or "Auto Orch". Again these were dropping off their boards so I opted to replace all of them with modern substitutes. I also did a couple of rounds of contact and busbar cleaning in the switching and keying circuits.
Everything on the organ was now generally working and I began the playing-in process over a month. This meant three to four hours of use every day. Every weekend I would have a list of niggles that had arisen such as intermittent contacts, dying divider packs etc that were failing from the sudden regular use of the organ. After four weeks it was fault free and I have enjoyed playing it every day since.
I must add as a footnote, my gratitude to those friends that know me as the "Lowrey guy" and have generously donated lots of spare Heritage parts to me which have made the cosmetic repairs possible - new logo strip, switch panel surrounds, foot pedal caps etc.
My Lowrey Heritage Deluxe DSO-1 Gallery