- Hits: 4892
It was about July 2000 that I received an e-mail from this chap in Florida, U.S.A. He was having some trouble trying to restore an old pair of Quads. The difference between him and a hundred others was that he was really starting from behind square one. By which I mean that these Quads would have made a bona fide ‘expert’ restorer throw up their hands in horror - everything that could be wrong with these Quads was wrong with them. This guy was starting almost from scratch, and I don't think Wayne will be offended if I say that he had almost “everything to learn” about the original Quad's functionality, although he was already very good at the cosmetic side of restoration. The other thing about Wayne was (and is) that he is prepared to stick at it, learn, and reach the goals he sets himself. The fruits of his labour? Today he is the proud owner of a mint condition pair of Quad electrostatics, and soon to be the proud owner of a bouncing baby, stacked pair.
Here is his story as he tells it - the good, the bad, the ugly. It shows that if you want to do it, you can. If you would like to contact Wayne you can find his e-mail address on my Links page. Oh, and I almost forgot - not really - Wayne is now one of the best restorers of the original Quad ESL in the world. See below:
MY QUAD STORY
Here we go.... I obtained my Original Quads in the Spring of the year 2000. Almost half a century after this wonderful sounding speaker went into production. I spent about 6 months refinishing my first set. ....It all started for me when a friend of mine approached me at my place of work and asked me if Id be interested in taking an old set of Quads out of his garage. He had enough frustration trying to fix them in the past and wanted to clean his garage out and make space for other things. Knowing what they were and remembering all that I had heard and read about them, believe me, I was more than eager to pick them up. Especially remembering articles that pointed out the fact that they were more natural sounding than the Quad ESL 63, and I was familiar with the sound of these... There was no price for them. He offered them for free, he just wanted them out of the way. Needless to say I picked them up that day after work. I would have left work to get them if need be. I remember driving home in my pick up looking out the rearview mirror as often as possible (without getting in an accident) to admire the old amber looking oak that was covered in gray over spray paint. In addition, the look of the rear grilles was nothing but brown and rust, with an amazing clean look to the original aluminum tags that are tack welded to the metal. The audio transformers and high voltage supplies were up front with me as well as all the panels. Everything was an absolute mess. I wasn't frettin to much about the cosmetics of anything as I had plenty of confidence about making things look new again. The operation of everything at this time was very unclear to me and I was a bit concerned about the actual process of fixing anything electronic.
It was about this time that I arrived at home and started sorting out the pieces onto my garage floor. I laid everything out to try to get a mental picture of what does what and where things belong as far as clipped wires and what not. After looking at it for a long time I decided that there was definitely enough involved with these things, that I was definitely going to need some help. I typed in "Quad Electrostatic Loudspeakers" on the web and got a couple different references. I don't remember exactly how I got to this wonderful person named Gary Jacobson, (Quad expert). A person who lives in Australia!!!! A person who is not only filled with exacting information on the Quads, but a very patient person, not to mention an earnest desire to help others. Another person I would like to give special thanks to is Sheldon Stokes (Quad expert) as well. Like Gary, his interest in helping me was a neat experience, and Rob Mackinlay (Electrostatic speaker designer) as well. All these people were very interested in helping me get my Quads working and all offered exceptional opportunities for me to learn through the coarse of my refurb experience. I may not mention these people often enough in my story that's why I wanted to tell you now and upfront that they are all wonderful people.
I started with the oak on the speakers. A lot of this was discolored probably from old and faded urethane, not to mention a lot of gray paint that apparently got on there from somebody trying to spray the dustcover film when the panel was installed. I used a 100 grit sandpaper to bring the wood back to its natural grain. 60 grit is to rough- it leaves deep scratches that are to hard to remove later. A final rub over with the 220 grit then they were ready for a nice clear coat to show the real grain color of the good quality oak that was used. This finish process on the wood was probably be the fastest finished part of the entire project.
I also redid the frame. I removed all the old layers of crusty dried out flat black looking paint and put a nice satin black back on. For a custom look, I removed all the black from the top and bottom rails that have a nice rounded half moon shape. I wanted a nice contrast of detail to the top and bottom trim work on the frame. The frames and all the coinciding oak was finished in a bout 3 days, except for the fragile dustcover frames. Removing all the old tape and glue is a slow process as these frames are very fragile. Be careful not to crack them.
Next, I began removing the old dried yellow tape from the panels. This is apparently a very good (when new) insulating tape. There are parts that still have that thick rubbery feel to it. Much better than standard electrical tape. Once this was done to all the panels, I looked at the prospect of removing near 400 rivets from a combined six panels. Two treble panels and four bass panels. Wheeeeehhh! I had remembered somebody mentioning to me the idea of pinching the backside of the rivet on two different angles to get the rivet small enough to pull thru the other side. I did two panels like that. I didn't want to retire pulling rivets so I decided to drill them out. At first, the rivet just spins in its own whole once the drill bit gets a grip to it. So I placed the panel on a matted scrap piece of carpet that was in my garage and was hoping that the rivet would somehow be stopped from spinning, it worked quite well, as the spinning rivets soon became enmeshed into the fiber and could no longer spin. This technique turned out to be kind of neat. When I was done with each panel, you could see the exact pattern of rivets stuck in the carpet. This piece was no longer any good for wiping your feet.
I remember the experience of getting the first panel opened. It was interesting. I was learning a lot. The conductive 1/4" foil on the inside of the stator plates was completely trashed. Some parts were burned away and a low resistance continuity around this trace was no longer happening. I also saw some chunks of what looked like salt around this conductive path. Apparently, this formed from some high humidity environment reacting with the high voltages; (I think). All the foil tape on all the bass panels was in terrible shape. You can replace this very easily for hardly any cash. I bought a roll of 2" wide foil tape for about 6 bucks at The Home Depot. I cut pieces the approximate length of the panels then cut thin 1/4" strips to put back on. First, let me tell ya - before you can do this you must remove the nasty hard epoxy type glue that was put on with the original diaphragms. I use a 1" putty knife and Acetone for cleaning in between durations of scraping. I like to get the panels back to clean plastic for the ultimate in rebuild quality.
After putting all the foil strips back on I secured the corner connections with silver loaded paint. You want to do this to ensure continuity throughout the path. The continuity can be checked with any inexpensive DVM by placing the probes across the plate so that each one is touching the foil strip directly adjacent from each other. My experience has shown that with good silver connections a reading of 1-3 ohms is obtainable. If it is higher, say 100-200 ohms the panels will still work. Humidity can alter measurements as well when the panels are open in the rebuilding process. I have experienced different readings on these conductive paths from one day to the next without changing anything, or without even moving the stator panels for that matter. Weird stuff. The conductive layers for the audio signal are on the outside of the bass panels where all the perforated holes are. The 1/4" traces on the inside of the bass panels are the HV, (over 5KV) that supplies the charge for the diaphragm.
After feeling good about the finish work on the bass panels, I was off to start the treble units. Here I learned (Gary, Sheldon, Rob) that all the conductive materials are on the inside of the stator plates. Both the audio, which is on the three perforated sections of the panel, and the diaphragm charging strips which are in the raised area that goes around the stator plates. Everything here seemed to be pretty well on mine except for a couple of real cracks in the plates themselves. This also messed up the continuity for a proper path charge as the crack breaks the "line". I was able to melt the plastic with my wide tip soldering iron, fairly strong too, and enabled me to use silver paint to bring the conductive path a smooth travel again. At this point, I checked for good continuity and was completely confused why the readings were so high and or no readings depending on where the probes were. I later realized after some other very "LARGE' mistakes that I had used a drill bit that was just a tad to big when drilling out the rivets. It took away too much of the conductive pathway that runs down the central spacer area. My advice here would be to use the smallest bit that removes the rivets and not a bigger one that works easier. That is what I did. Here you will also see the masking tape that serves as a resonance control on the very thin film membrane. After fixing this problem (with silver loaded paint again) the measurements were making more sense. It will be good if you can avoid having to use the silver paint for many mistakes. At 14 dollars for a tiny bottle it gets expensive however, it is a great product.
After I had all the panels fixed inside and out with the conductive materials and the cracks now it was time to address this one treble panel that seemed to be awful warped in regards to its shape. The one lay nice and flat while the other looked like it needed heating and squeezing with some flat pieces of wood. I can say that the shape of the panel was much improved after I was done. It took along time and patience to get it straight again, but to me it was worth it. If you come across this problem, be very careful with the heat gun as the plastic stators cannot handle a lot of heat. They will start to melt quickly and may make matters worse - Be Careful!
Now that that was done, it was time to address the wiring to the panels, as all the solder tags were broken off. I carefully used a small tool to thread the inside rivet body wall, and then used a very small screw to fasten an electrical "eye" connector to the rivet. The wires were first soldered into the eye. Very tedious work. You must also be aware when having to do this kind of repair that the rivet does not spin. If it does the conductive coating that's on the inside must be overlapped back onto the rivet then sprayed with a layer of insulating lacquer. If not, then there will be a hairline crack around the rivet where the conductive material has been separated from the connection point. Be sure to use your DVM to check that all is well. After getting all my connections done like this I was off to make the biggest mistake of all.
I decided that the panels would look much better in my room if they were black instead of that ugly gray paint that Quad used. So I sprayed them, and they looked beautiful. It was now time to start the process of reinstalling the membranes. I used Rob Mackinlay's conductive opaque coating the first time around. I finished putting the film in all of them fairly quickly and was ready to bolt them all together and install the dustcover frames.
After doing this, it was time to rebuild the EHT units and crossovers. I was able to get the parts at the local electronics surplus shop. The capacitors used will cost some money because they are a very high voltage rating. I finished soldering all new parts on the crossover tag board (underneath the big canister) and got the new parts soldered onto the rectifier board. This is the smaller board that's in wax with the top sticking out of it near the Mains (wall outlet) power supply. For future use, I will use the oven to remove the wax from these oldies. Experience has taught me that the heat gun only burns other things around them. The heat gun can also generate enough heat to undo solder connections and melt color jackets around wiring, so be careful. Unsolder the wires from the HV supply, remove the nylon bolts that hold the phenolic box to the frame then use the oven. About 300 degree's melts it out pretty well.
It was just about time to plug these babies in for the first time. After doing so, all that happened was very bad arcing at the Mains output transformer where the 600V wire connects to the rectifier card and on that little phenolic strip. In pulling the plug, right away I was pretty upset. It had been at least two months by this time and I finally had them all put back together and looking great. As it turns out, there was some kind of grounding error down here and if I remember correctly, that was the first time around. To get right to the point- my lovely idea of spraying the panel black was coming back to haunt me. Latter tests and the fact that I couldn't get things to function correctly narrowed it down to the black (carbon filled) paint. This paint on the outside of the stators had made contact with both the audio and HV signals and was bringing them together. Mind you, now the black paint was throughout all the perforated holes. Removing and undoing this mistake set me back quite a bit. I got it all off though and later found out that white would probably be the best color for the panels. I did a test with the DVM and it showed no conductivity. I wish I had known to do this test before the black paint. Live and learn right.
OK, now I had all the panels back together again, it wasn't until after this next time that I had finally learned to test one panel at a time. I had to undo the panels a second time around, as the small screws that I used on the rivets (to hold my connections) were apparently a fraction too long. This was essentially closing the air gap to even a lesser distance and was causing the panels to be shorted out. Up to this point, I had not been able to play any music on them. Now, they would play music but with any volume at all, they would short out and the amp would kick off. So, it goes, with slightly smaller screws. After this problem was fixed, I still could not get any volume from the panels. I was getting very frustrated and felt as if I was to my wits end with these things, as I had been thru so much with them. There were times that I wanted to snap them over my knee. With lots of support from Gary, Rob, and Sheldon, I was able to continue with different things to try.
I had tried so many different methods of membrane coating and resistance levels also. Nothing was yielding any worthwhile results. It was about this time that I had discovered that possibly the sharp points done at my solder connections could have some voltage loss. So I mentioned that idea to Gary and he assured me that HV leakage is a major issue with any electrostat. It was around 2 o'clock in the morning when I was ready to try a set of the panels once again. This time I had all my solder connections covered with liquid electrical tape and the rectifier cards back in the wax. I also decided to cover the crossover components and solder joints here as well with the liquid electrical tape before pouring wax over the whole thing. I plugged them in... and it was sweet, sweet quiet. No arcing, no humming, no buzzing; just dead quiet. I felt very happy but assured myself not to get too excited yet; as I had been through enough and that maybe something else could be wrong. I decided to give the speakers (3 panels) 5 minutes to charge before trying to play music with them. The 5 minutes past and I went back into my music room where I had the three panels leaned up against the wall. Just a few bolts in each one and a towel folded firmly over the top edge of the panels to keep them from leaning directly on the wall. The wires were everywhere on the floor but all the panels were hooked up. I had the connection point of the wires covered on the floor area, as I didn't want to accidentally touch any of them. I made that mistake with one of the bass panels before this. It's a real quick wake up call!! Anyway, I put the disc in (Elton John) and hit play; and guess what? They played!! They played like nothing I had ever heard before. I was so relieved and full of joy. I couldn't believe that I had finally done it. That night I sat in front of the three panels listening for about 3 hours. I couldn't believe all the details and definition that was pouring out of those three barely assembled panels. All I could think about now was the fact that I couldn't wait until the others were done and in the frames. I knew now what I had to do. I made a lot of mistakes rebuilding my first set of Quads. It was enough for me to feel like I've rebuilt 10 sets. I got the other panels done and at this point all the membranes have the Nylon (original) coating on the membranes from Gary Jacobson.
The installation of the internal diaphragms themselves is not a hard task. I used an ultra thin- 2-sided tape instead of glue. Its really just a matter of taping the diaphragm down to a glass table top, placing the adhesive strip around the perimeter of the stator, being sure not to lay it on top of the conductive foil, then gently placing the stator down on top of the film after its coated on both sides. After you remove the tape from the glass, its time to turn the stator over and heat shrink the film. Be careful to hold your heat gun at least 10 to 12" from the film and keep the gun moving in a slow back and forth movement. It won't take long before the film starts to move. When it does you simply move the wrinkles right out of the film.
After this is done, its time to melt holes in the diaphragm with a soldering iron where all the replacement nuts and bolts will fit through, to hold the stators tight together. Be sure to hold the soldering iron as still as possible. Shaking hands are not good for this task. Once this is done it's time to put the panels together. I snug the nuts and bolts just a bit with a wrench- don't over tighten, you'll risk cracking the stators- especially the perimeter bolts.
After the panels are together, new wiring is soldered to the correct solder tabs and dustcover film is put back on, then its time to start the task of getting the panels back in the frame. I found it easiest to put the treble panel in first, then one bass panel at a time. In the process of installing the bass panel the treble panel will be pulled a bit out of position, that's OK; there will be time for all the little scotches here and there to be sure that the dust covers are lined up nice and even with each other. This part of forcing the bass panel to fit behind the top bracket on the frame seems a bit scary at first. I was feeling like I was going to break the panel in half. The best way for me to do it was to position myself at the side of the speakers frame and while pulling the bass panel towards me at its edge with my left hand- the right hand is behind the stator with the thumb very firmly planted on the backside dustcover frame. The idea here is to push hard enough with the right hand to cause the arch and when you feel the dustcover slip over onto that wood side piece that's on the inside frame you can let tension off with the right hand. Just put a bit of tension here once again, as you pull in towards yourself with the left hand. It does take a bit of practice. It's easy to damage the dustcover film at this stage in the refurb. Especially with the rear mounted thumb. If you slip and cause a dent in the film, this can be taken up later with a little more work with the heat gun. Repeat this same process for the other bass panel. Realign your treble unit before you start your other one.
After this next bass panel is in you can adjust the side-to-side position of the treble panel from the rear. While you're back there you might as well solder your wires to the appropriate crossover leads and HV leads, as well as the standoffs at the panels rear. Be careful not accidentally touch the dustcover film with the iron. After your soldering on the crossover and HV are done, a good coat of insulating spray won't hurt. I used liquid electrical tape. A glob of this at the connection points will alleviate some leakage problems. You have to remember that the power supply itself is not a very stiff one. You don't need drainage of any kind or in any place if you can help it.
After this is done be sure to make sure that your ground lead wire from the Audio transformer is connected back to the mains tranny, then to the mains frame for proper ground. At this point, run the machine screws through the bottom of the frame to hold the electronics to the base. This is rather simple. Don't tighten any of them all the way until they are all at least threaded and started into the frame's and or canisters. Then, it's plug in time. Let the new panels saturate with charge and let the electronics warm for about 5-10 minutes before putting music to the speaker. You might hear a cracklin' "Egg frying," sound when first plugging them in. This is very cool. It may seem at this point that you can actually feel the radiation of electricity around the panels. Don't touch them! Touch and feel them when you rebuild them, look at them, stroke them, dream about how good there going to sound, but once they are plugged in- don't touch them! You can, for safety, unplug them once a month or so to wipe the dustcover clean. A fast evaporating cleaner like denatured alcohol works well.
Before you secure the rear grille in place, you may want to do some listening tests. The Quad panels do not fit exactly firm and snug to every area in the frame. It will be a listening test period of probably a few days or so to work out the bugs. You may hear little rattles and buzzes here and there. Mine especially had big gaps at the top of the bass panel area and at the bottom of the treble panel where the bass panels over lap. Be sure to squeeze hard here when putting the brackets back in place. You may have to pre-drill some different screw holes if the squeeze bypasses the original holes. The panels at the dust frame points cannot be clamped too hard so don't worry about smashing them.