The tube is an OA3 (US designation), and it is one of my favorites 🙂. Unfortunately, it has a bit of a hum to it, so I'm going to find some tube dampeners for it.
The RCA jacks do indeed come from the pedal. The pedal controls the tremolo rather than the swell, though (I think there's a dead capacitor along the circuit somewhere), so I hope that works. So, what would be the process of tapping into the RCAs?
So, that's it? Just plug RCA cables between the organ and the mixer board?
Hey, I think I know what the trouble with the pedal might be—the tremolo only comes out of the 5.25" speaker, so there must be a problem with the circuit between the pedal and the 12" speaker! The pedal controls the volume of the tremolo, rather than the rate, so that must be it!
Anyway, if I want to keep the pedal functionality, what would I have to do?
Btw, here's a pic of the OA3 doing its thing in the dark. Beautiful...
Austin Leeds's Photos | Facebook
Austin Leeds's Photos | Facebook
I think Mike has cracked this one. 🙂
The amplifier is just an amplifier. The "functionailty" of the expression pedals is all happening BEFORE the signal from the organ section gets to the amplifier. So plugging those RCA jacks into a mixer or another line-level would keep the functionality of your pedals.
As it turns out, the pedal RCA jacks on the amp are actually inputs. I found this out by plugging my brother's FlipVideo into it—and the recorded audio played through the organ (the speakers worked surprisingly well). Now what?
The 5.25" (electrodynamic) speaker stops ticking when I turn the back assembly of it (the driver?) in a certain direction. Weird.
The 5.25" (electrodynamic) speaker stops ticking when I turn the back assembly of it (the driver?) in a certain direction. Weird.
Well, I would suggest that you're already halfway there. 😉
What you need now is some sort of breakout box that allows you to switch between the signals either going into the organ's amp, or out to a pair of conveniently mounted sockets to feed to an external amp/mixer/DI box. If you don't fancy making one, you can probably pick up a cheap AV switch box and use that. Something along these lines...
I know the one in the link suggests many inputs to one output - but it's a purely passive device and can be used the other way round. Connect the two cables from the organ to the "output" sockets on the box. Connect a pair of cables between any two "input" sockets of your choice to the organ's amplifier. Connect any of the other pairs of sockets to your external sound reinforcement as needed.
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Aha! I plugged the pedal cables into a mixer, and presto! They're outputs!
But is that safe? I mean, the amp isn't overheating or anything, and the sound is quite clear.
But is that safe? I mean, the amp isn't overheating or anything, and the sound is quite clear.
Woohoo! 😀
The amp in the Caprice shouldn't overheat. Let's face it, while the outputs from the organ are running to the mixer, the amp is not being asked to do any work. If the output into the mixer sounds clear, then it's not likely that you've got any serious impedance mismatch at the organ's output.
All you need now is to work out where best to mount a switch box and the external sockets so that the whole rig is easy to use when you drag it around to play live with... 😉
Sweet! I've got it running into a laptop with Rakarrack (an audio processor) and I've found out how to make it sound like a pipe organ (among other things). Whoopee!
I'd need an RCA extender, but the box should fit fine over by the 5.25" speaker, and it could protrude from the back just enough to plug the mixer in and plug in some speakers.
This is gonna be great! Thanks for all your help everybody!
I'd need an RCA extender, but the box should fit fine over by the 5.25" speaker, and it could protrude from the back just enough to plug the mixer in and plug in some speakers.
This is gonna be great! Thanks for all your help everybody!
I'll post some different sounds the organ can make now to SoundCloud and link them here later. Stay tuned! 😀
Yes I meant to plug the cables into your mixer as you are now doing. If you disconnect the speakers wire a 250ohm power resistor across the output transformers' secondaries (i.e. where the speakers were connected) so that you don't fry the output transformers.
That expression pedal still sounds kind of loopy. Would be interesting to see the schematic for that puppy. Looks like a nice organ.
That expression pedal still sounds kind of loopy. Would be interesting to see the schematic for that puppy. Looks like a nice organ.
The speakers are still hooked up, they're just not getting any input. I've bought a couple RCA to 3.5mm cables, plus an adapter, so I can run it through the laptop and back into the speakers.
Yeah, it would be interesting. I think I am going to order the service manual, and maybe have you guys translate the schematic for me.
Another thing—the tremolo/pedal weirdness is confined to the amp. Whatever source I plug into the amp, the tremolo thing still happens when I flip it on and press down the pedal. It's kinda weird hearing my mp3s with a beating tremolo in them...
The line output from the pedals, though, has a perfect tremolo that can't be changed by the pedal, but is also affected by flipping the tremolo switches (L and F) on and off. The pedal also won't control the volume through the line out.
The line output from the pedals, though, has a perfect tremolo that can't be changed by the pedal, but is also affected by flipping the tremolo switches (L and F) on and off. The pedal also won't control the volume through the line out.
OK, so there is something goofy in the amp itself. If you haven't already done so a fairly comprehensive recap is in order to avoid letting out the magic smoke. It is possible that just doing that might solve the oddities.
I think you are going to enjoy this piece.
Oh, wait. The pedal definitely should be controlling the volume. Have a look at the pedal and see if it has pots (potentiometers) on it or if it is a capacitive or optical type. If you are going to play music with this thing the expression pedal needs to work properly.
I think you are going to enjoy this piece.
Oh, wait. The pedal definitely should be controlling the volume. Have a look at the pedal and see if it has pots (potentiometers) on it or if it is a capacitive or optical type. If you are going to play music with this thing the expression pedal needs to work properly.
All right. I'm going to order the service manuals and owners manuals, so that should help. Also, I haven't soldiered before, so I'll need some practice before I try recapping it. Where should I start to recap it—the amp, the stops, the oscillators?
Enjoy what piece?
I don't know what to look for to determine what my pedal uses. Tomorrow, I'll upload some photos of the pedal I snapped the other day and link to them on here.
Enjoy what piece?
I don't know what to look for to determine what my pedal uses. Tomorrow, I'll upload some photos of the pedal I snapped the other day and link to them on here.
By Piece I meant the whole thing... like in that is a nice piece of kit.
I presume that the PS on the PA chassis supplies everything in the organ so that should be done right off. All the electrolytics should be replaced. Any paper or wax caps (used for coupling mostly) should be replaced with new film caps. Coupling caps can cause funny distortions and effects as they screw up the bias points.
There are probably suspect caps in any preamps (like tremolo or reverb amps) too. I await the pedal pics as that may give us a clue.
I presume that the PS on the PA chassis supplies everything in the organ so that should be done right off. All the electrolytics should be replaced. Any paper or wax caps (used for coupling mostly) should be replaced with new film caps. Coupling caps can cause funny distortions and effects as they screw up the bias points.
There are probably suspect caps in any preamps (like tremolo or reverb amps) too. I await the pedal pics as that may give us a clue.
Here's the pedal pic: Austin Leeds's Photos | Facebook
So, recapping the amp would require me to detach it from the organ, right? What safety procedures would I need to observe for something like that?
So, recapping the amp would require me to detach it from the organ, right? What safety procedures would I need to observe for something like that?
Glad you've decided to keep this tube Conn original. Somebody needs to, and I don't have room with the 2 hammonds and the 2 pianos. These things are visually so cool with the tubes glowing. Put a plexiglass cover on the back instead of the cardboard. Chop & midiize a kimball or a lowery transistor organ for the road.
For safety, read aikenamp.com tech button introductory button aiken's safety procedures for tube amps button. Pay special attantion to the discharging the capacitors rule, and then measure them at below 24 V before touching any metal. Once again, your organ is so old, you don't have many electrolytic capacitors. The tall cans twistlocked into the metal chassis, you need a 130 W pistol gun to unsolder the twist tabs. Wear safety glasses, solder splashes. Going in you need a WP35 or WP25 iron. Buy a chisel point tip, the stocker pointy tip is too slow on tube stuff. Use lead-tin rosin core solder, not the silver stuff, it melt at too high a temperature. No acid core, it eats the leads off your parts. R****S***** solder has worked for me, you have to buy a whole pound from the big boys. RS irons are ****. While you have the cans off measure the big 1W resistors between the terminals, they tend to go high as they cook over the years and limit your output power to below OEM.
Learning to solder on the organ is fine, but inspect when done that the joint looks wet, not crystalized, and that the wire won't pull off. Your electrolytics have plusses or minuses on an end, or the cans have moons, squares, and circles on the various plus terminals. The paper caps might cause off frequency or a funny sound, but won't blow up or short out your power transformer like electrolytics will. Like aiken says, install an inline fuse on your AC power to save your transformer. The holders from the auto supply work fine at 120 V, but you need an MDL3 or 4 slowblow 1/4x1-1/4" fuse from the place you buy the capacitors from. Divide watts on the organ label by 110 to get amps. (was 110VAC in 1955). Amps is the number after MDL on the fuse. For parts I use newark.com, mouser.com, and for FP can caps (the tall ones) tubesandmore.com or triodeelectronics.com. For axial lead electrolytic caps, use 2000 hours up rated ones so they will last more than 1 year, and newark has the rating in the selector table so you don't have to wade through the **** caps. Most brands have both **** cheapo lines, and long life lines, buy the latter by the number, not the brand.
For safety, read aikenamp.com tech button introductory button aiken's safety procedures for tube amps button. Pay special attantion to the discharging the capacitors rule, and then measure them at below 24 V before touching any metal. Once again, your organ is so old, you don't have many electrolytic capacitors. The tall cans twistlocked into the metal chassis, you need a 130 W pistol gun to unsolder the twist tabs. Wear safety glasses, solder splashes. Going in you need a WP35 or WP25 iron. Buy a chisel point tip, the stocker pointy tip is too slow on tube stuff. Use lead-tin rosin core solder, not the silver stuff, it melt at too high a temperature. No acid core, it eats the leads off your parts. R****S***** solder has worked for me, you have to buy a whole pound from the big boys. RS irons are ****. While you have the cans off measure the big 1W resistors between the terminals, they tend to go high as they cook over the years and limit your output power to below OEM.
Learning to solder on the organ is fine, but inspect when done that the joint looks wet, not crystalized, and that the wire won't pull off. Your electrolytics have plusses or minuses on an end, or the cans have moons, squares, and circles on the various plus terminals. The paper caps might cause off frequency or a funny sound, but won't blow up or short out your power transformer like electrolytics will. Like aiken says, install an inline fuse on your AC power to save your transformer. The holders from the auto supply work fine at 120 V, but you need an MDL3 or 4 slowblow 1/4x1-1/4" fuse from the place you buy the capacitors from. Divide watts on the organ label by 110 to get amps. (was 110VAC in 1955). Amps is the number after MDL on the fuse. For parts I use newark.com, mouser.com, and for FP can caps (the tall ones) tubesandmore.com or triodeelectronics.com. For axial lead electrolytic caps, use 2000 hours up rated ones so they will last more than 1 year, and newark has the rating in the selector table so you don't have to wade through the **** caps. Most brands have both **** cheapo lines, and long life lines, buy the latter by the number, not the brand.
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Speaking of Kimball...
Uh, heh heh... Now might be a good time to introduce you to my new baby:
Austin Leeds's Photos | Facebook
😱
Uh, heh heh... Now might be a good time to introduce you to my new baby:
Austin Leeds's Photos | Facebook
😱
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