Lowrey Organo

[Phil_S]

I received the organ apparatus from a friend today, not the piano. Here's the exact model, though his piano is in pretty ratty condition:
http://cgi.ebay.com/Janssen-Piano-w-Low ... 0089194790

Here is my amp porn of the thing:
http://home.comcast.net/~psymonds/Organo.html

Basically, this is an organ "attachment" inside a piano, consisting of a 60-tube tone generator, an 2x 6V6 amp, and a Jensen P10Q. The amp section includes PT, OT, and what must be a 12V 11A filament transformer. The tone generator has 48 12AU7's and 12 12AV6's. The 12AV6 is half of a 12AX7 in a 7-pin 12V bottle. The amp has a 2 each 6SL7, 6SN7, 12AU7, 6V6, 6W4 (I guess 2 half wave rectifiers make for a FW?).

The speaker is dated 1963 and I think the tubes are dated 1956. Regarding the tube dates, I'm assuming the code 56-26 means 26th week, 1956. These are mostly GE badged. The 12AV6's are RCA. The 6V6GT's are GE black plate. The rectifiers are Raytheon.

Also, lots of nice looking carbon comp resistors, green Tropicap coupling caps -- many 600V rated, and at least a dozen or more bumble bee caps. There are 48 cheap wafer sockets for the 12AU7's in the tone generator and better stuff elsewhere.

There must be a mile of wire in this thing, tidy old school string ties bundles, nice colors, and cloth, of course. It's obviously hand build and the work was don't by someone who knew how to handle a soldering iron. The build quality is, IMHO, first-rate quality.

The question is, what to do with this beast? Part it out? Keep the amp and Re-purpose it? Sell the speaker (these go for close to $100 on eBait) or put it in a cab and use it? Sell off the tubes --what $2 each, $5? Any idea if 12AU7's will command any sort of price assuming they are good?

What do you think?

[Structo]

Holy Cow!

That makes the Hammond organ amp I bought look like a tinker toy.

Isn't it amazing the point to point wiring in those things.

Mine was from 1959 and all the tubes were still good!

Good luck, looks like some nice parts in there.

I see that row of light bulbs in the last shot.
Are they using those to drop current to the power amp?

[Phil_S]

Hi Tom,
I'm told they are relaxation oscillators.
Read here http://en.wikipedia.org/wiki/Relaxation_oscillator

I'm having some trouble mustering up the courage to tear it apart. Its chances of being an organ again are quite remote. I'm guessing the tubes are good, though, at this point, who knows?

There's a part of me that says to do a cap job on the amplifier, and stuff it in a combo box with the P10Q. It will need to be a cube due to the squareness of the amp. I'd park the amp on the bottom, old combo style, open back.

If I could get myself to that point, I think pulling those 12AU7's and selling them off on eBay could happen. Then, I get to harvest all that great wire and tube sockets for future use -- a lifetime supply.

OTOH, I could build the ultimate all 12AU7 amp. 2.5 triodes for gain (maybe 3.5), concertina PI, 16 12AU7's into a 1.5K PP OT (that's 16 triodes on each half), I'd guess about 60-80W (or 8 double triodes into ~2.8K primary for about 30-40W). Or, I could build the preamp and PI from the 12AV6's -- that would take somewhere at least 4 and as many as 7 or 8 tubes depending on number of gain stages and type of PI.

I could always run two channels on the front end to double up on the preamp tubes. Maybe it should be a stereo amp for hi-fi use? That would about consume all the tubes.

How wide do you think that chassis would need to be? I'm guessing I could run a 4x4 square of noval sockets for the power section and it wouldn't be all that imposing, width-wise. I'm just thinking...it came with that ginormous 12v filament transformer and it would be a shame to waste it.

Of course, I'm half (or more) kidding about this.

Phil

[Structo]

If it is anything like my Hammond amp, the sockets were riveted on as well as the terminal strips.
Then the leads of each component were wrapped around terminals making salvaging them pretty unrealistic.

I was just going to remove the components that I wasn't going to use but after trying to take stuff out I realized that it wasn't going to be easy to do that.
So I gutted it of everything except the rectifier socket and PT.
My amp had a field coil speaker and the coil was being used as a choke in the power supply so I had to add a choke to the amp and use a different OT.

[M Fowler]

I just removed what I could and rest is junk. The only wood I saved was some hard wood bracing and the speaker baffle board and speaker.

Oh my wife is using the bench as well.

The tubes I have been using in various projects as well as some of the caps. Two of the turret boards are going into small fender chassis. The power supply, faceplate next to the keys that says Hammond has a pilot light and two knobs. I am cuttiing down that face plate and using that in a Hammond combo amp I am building out of parts. Chassis is too hard to convert for my use so I will just use another chassis but the power supply is good.

Its work salvaging this way guys.

[Phil_S]

Yes, wafer sockets are riveted and would require drilling. Cheap sockets, probably not work the effort...BUT...there are 5 on a metal board and could possibly be trimmed down and made useful as a unit to drop into a chassis.

The boards may or may not be salvage fodder. Many nice CC resistors with long leads could at the very least be clipped and still useful.

There are a dozen bumble bees...low fruit for the audiophools on ebait?

Any word on those tropicaps? 600V rated, long leads, and a very nice turquoise color!

The wire is too pretty to leave behind. There is a long trough in the middle, at least 3' where I might find a lifetime supply of good wire.

I think I will start by extracting the amplifier and removing the filament transformer. Anyone need a 12v 11A transformer? No CT. I'm guessing at the 9 or 11A based on the tube count. 60 tubes in the tone generator at .15A each = 9A plus there is stuff in the main amp. Even if it was 9A... I could run it through a voltage multiplier circuit, working for ~ 3x, I'd still have 300mA. I have to put pencil to paper on that wild hair...maybe B= in the upper 200's? 12*2.88^3 = 286. Is that right?

[Cygnus X1]

:Drool:....

My 50 dollar thrift store goldmine was a Baldwin spinet.
Got it spring of 09 and it remains a gold mine of parts.

I went ahead and cleaned up the t-shaped turret strips
(dental pick and soldering iron), and drilled them out and still have half of them left after 3 other amp builds.
5 bux each! Sturdy and have a great smell to them as well.

And the wire, both cloth and I guess PVC covered (not sure) was PRISTINE. Seriously great wire. I have it carefully stored and use it all the time.

What else...loads of 12AX7A Phillips tubes, all tested strong. Some of those Sprague BB's, a ton of tan Sprague caps.
Hell there are parts of this organ I haven't even touched yet and the reverb and main amp are still intact.

[Phil_S]

:Drool:....

You did better than me. No need to drool. I traded a complete custom built guitar amp for it -- for my friend's daughter, so I really feel very good about it. Monetary-wise your $50 was way less. You got great 12AX7's. I got 12AU7's. Still, I think it was a fair trade and if it wasn't, I still get some fun out of it.

[Cygnus X1]

I only own ONE tropicap...luckily an .022 uf that I stuck in
my Hamer Phantom A4.

Sounds better than the PIO I had in before, crisp.

Yes I have heard good things about those.
Only problem is they don't have the reputation that the BB's have.

Hope you have usable values...the BB's I pulled out of that Baldwin were in oddball ranges I can't see much use for in either amps or guitars.

[Phil_S]

I lucked out on the Tropicaps. There are about 60 of them, values include .0012 .022 .033 .015 .1 .047 .01 probably all useful somewhere. I think I've used something close to these one time or another in an amp. They all look practically brand new, not sticky or oozing anything.

I need to decode the dozen or so BB caps to see what they are. I found this!
www.pickguardian.com/.../Sprague%20Bumb ... 0Chart.pdf

I think there is a half-lifetime of carbon comp resistors with long leads, too. There have got to be a couple of hundred in there.

It seems there is an LC network that is tied to the lightbulbs for each pitch. I'm thinking this is how they tuned the tone generator. Clever!

[Sonny ReVerb]

Your link isn't working with the ellipses in there. Try this:

http://www.pickguardian.com/pickguardia ... 0Chart.pdf