Does anyone know what kind of tubes a Lowrey Virtuoso's (TRO-R1) power amp takes? and if so, which socket do they go in (brown or black) ? at this point it's alot to ask, but where are all the ins and outs (reverb send, reverb return, guitar in, speaker out)?</p>
Those do NOT look like tube sockets. I can recognize two power transistor sockets in the one picture, each with a square power resistor attached. So the amp is probably solid state...</P>
It is likely the things you think are tube sockets are used other in's and outs... If I had an overall picture and more views I could probably recognize more details...</P>
It appears that this is ONLY the power amplifier with no preamps and it is transformer coupled at its input by the transformer near those two power transistors. The transformer is mounted on the end. The rest of the stuff is probably power wiring and the "tube sockets" are actually connectors to send power to the preamps and rest of organ. I suspect, although the pix don't show, that there is a power transformer on the other side of the chassis out of view.</P>
I am an electrical engineer and I can recognize components and I will say the circuits here are very simple and the wiring is really messy in your pix.</P>
I'm sorry i didn't say i Know where the tube sockets are, they're on the right hand side of the second picture (the one where you can see the right edge). And you said the wiring was messy, but i haven't touched it i believe it's factory Lowrey stuff. I just need to know what tubes it takes.
Fredy has given the correct information, as always!</P>
The letter T in the prefix of a Lowrey model from this era stands for Transistor, so the organ is all solid state. No tubes at all. Incidentally, I haven't got any information on the model TRO Virtuoso at all, it simply doesn't appear in any of the books I have, nor do I recall the name Virtusoso being used for a model. The nearest I can get is the TBO-R Berkshire. If you have a pic of the organ I'd love to see one, or are you just gutting the organ for the amp?</P>
Andy</P>
It's not what you play. It's not how you play. It's the fact that you're playing that counts.
I would really need to print the photos to gleen much more, but I can see an electrical code violation that the neutral (white) input cord line is fused and the hot, black wire goes to the black plug... likely goes to a power on off switch.</P>
The wiring is MESSY, typical of consumer electronics of the era... It looks all original... I suspect the brown socket plug sends power out to the organ... There are two adjustable screwdriver pots near the power transistor sockets that are for setting the bias of those transistors.... There are two black diodes on end in the other photo that are the main rectifiers attached to a canned filter capacitor... I could ALMOST trace out the wiring from your photos...</P>
Being the neutral input is fused, they look like they may have a .22 cap creating a false ground to the input power line and it might make the chassis a bit "hot" so be very careful... Would recommend using a line isolation transformer when experimenting with this one.</P>
You would certainly need a preamp/driver to drive this amp.</P>
More info: After expanding the pix a bit more I can see a third power transistor used as a driver for the transformer under that tapped power resistor. In addition there is a small TO92 style transistor (three leads ablut the size of a pencil eraser)near it on a terminal strip. So that is probably a pre driver. You could trace the base of the TO92 transistor to find the input.</P>
One might exppect the RCA style jack to be the input, however one would NOT expect a big power resistor to be connected to it. If one had an overall pix, might be able to point ut moore...</P>
maaan, I must've gotten gypped. But are you shure? they sure look like tube sockets to me, does the number 573 mean anything? it says that on both the plugs, here's a picture. http://leviman2001.googlepages.com/DSC04105.JPG (sorry about the lack of focus)</p>
heres that main overall picture, it's not too good though, my camera is old.</p>
I guess I don't understand the "gypped" thing... </P>
The amplifier is DEFINITELY a solid state amplifier. You will find three diamond shapped power transistors on the top surface... They might have a number like 2N3055 or something similar on them... They will have an insulating pad or mica between their metal case and the chassis. The two close together are the power amplifiers and the one by itself is the driver for the other two and may have a different number on it. I can tell by the wiring that the output transistors are connected in a "totem pole" connection.</P>
The two sockets, one is a nine pin and the other an eight pin are the external connections to the rest of the system. The power on/off switch is involved with pins on the black connector...</P>
If you are looking for a tube amp, you will find that the tubes will be mounted on the top of the Chassis AND there will be at least two good sized transformers usually on the top of the chassis... You will usually have at least 4 tube sockets or more...</P>
A few tube amps will have external connections going through a single socket that may be mounted on the same surface as the rest of the tubes. An example is the Macintosh amp that has a power supply seperated from the amplifier and joined by a jumper cable.</P>
MOST tubes found in audio amps will have no more than 8 pins similar to the black connector OR smaller sockets that may have nine pins for the minature tubes...</P>
If you were sold that as a tube amp, you've been 'done', in UK language!</P>
Those are 8 and 9-pin Amphenol type sockets. Lowrey used these for connections to external speaker cabinets, as well as for internal connections from one part of the organ to the other, as Fredy says</P>
NO TUBES in this, or any other part of this organ.</P>
Andy</P>
It's not what you play. It's not how you play. It's the fact that you're playing that counts.
I guess i have been had then! oh well it was only $45 and it has a huge reverb tank! i guess it'll be easy to get this thing going though. Course now the next question is which prong is what? (in, out, send, return, on, off)
I would trace out the circuit. It isn't that complicated... then you will have a schematic to work with. I could ALMOST trace it from the photos... </P>
With the schematic it should be easy to find the ins and outs... The power input and connections to the primary of the power transformer should be real easy.... the switch for power likely connects to two pins of the black connector... </P>
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That seems like a lot of work, I'm not too good with that kind of stuff. I found out what gives out 120v ac in the black plug, i was sticking a wire in the plugs and accidentally shocked my hand pretty well with it, lol.
The camera angles aren't such that I can make out enough to be sure but in regards to the black plug:</P>
The heavy bare wire is a chassis ground and PROBABLY one speaker lead.</P>
The input neutral cord connects to the backof the black fuseholder.</P>
The black plastic wire is HOT side of the line, unfused.</P>
It appears that the NEUTRAL input line has a 20 amp fuse to one of the pins, fuse is in sleeving. Possibly to run other things like lights or other 120 volt devices in the organ.</P>
It appears that maybe the black lead (cloth covered) of the power transformer is wired to the neutral after going through the black fuseholder.</P>
It appears that POSSIBLY the white primary transformer lead goes to a pin. It is CLOTH covered. I suspect this may have to be connected via a switch to that black plastic lead to turn on the unit.</P>
The GREY plastic lead appears to be a filter going to a .22 mfd cap to neutral. This may be for noise suppression of switch.</P>
The brown plastic lead appears to be input neutral fused by the black fuseholder.</P>
I SUSPECT that the blue plastic lead is one speaker lead and the heavy bare mentioned erlier is the return for the speaker.</P>
Realize it is very difficult to trace this from your pictures as I don't have all angle shots and ability to look under components. One could trace the whole amplifier in probably 30 minutes.</P>
I would recommend using the trick of putting a 150 watt light bulb in series with one of the power input wires to act as a protection fuse while experimenting.</P>
BEFORE connecting a speaker, verify that zero volts DC or VERY close to it exists where you connect the speaker.</P>
Use this information at your own risk as it is very hard to do this by way of photos. Use recommended light bulb trick to protect when firing up and an isolation transformer for safety as the neutral and colors for hot and neutral are really not per code or good design praactice.</P>
There are service manuals available for the Holiday by searching and I think there is one on Ebay right now.</P>
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