Output box on Conn

[Martin B]

Evening all

New Conn owner with many questions as have moved up down sideways from a Lowrey.

Can anyone tell me, the Conn sytem for speakers,
on this 644 is the external speaker tab on the right hand side, is this for turning on and off the Pipe speakers, i have just got some and was unable to find anything on the amp to wire them to so i searched and found to connect into the only 6x9 speaker in the organ that is for the strings reeds etc. the pipes do now sing very niceley but wondered if they should be connected somewhere else so this switch would operate them when needed.

the only thing in the organ is this output box but no metion of pipe speakers just two different tone cabinets, can someone explain what these are and if indeed there is a take off for the pipes to operate via the tab

Thanks

[Hamman]

Those connections on the box are for external speaker cabinets with their own amplifiers. Nothing but pre-amp level signals here. The conn speakers need a amplified signal....such that as you derived from

[Silken Path]

Hi, Martin - on my 643 (possibly a 1975), there are two connectors near floor level on the left for direct connection of Conn pipes. These are push-on male connector types, with three per side. The box you're showing in the picture is above them. My organ has two switches - one is Internal Speaker on-off, and the other is Pipes, Organ, Ensemble. My pipes are the 145s - the tall ones.

[Martin B]

Thanks for that info will have another look around in case i missed them

[edkennedy]

Output Schematic

Here's the amplifier and speaker schematic from my 645. It shows the pinout for the connectors in your picture.

[Martin B]

Many thanks., will keep a print off for the future, sadly i cannot understand it , i am trying at the moment to learn about this kind of thing.

[Hamman]

Well, I understand that I was wrong about the signal level.......I guess it is speaker level however, reduced down with resistors to be able to drive external amp(s)

[andyg]

As I said earlier, the 644 and 645 are very different instruments, from different eras so don't make assumptions that the schematics for one will directly relate to the other.

That said, the outputs are almost always likely to be speaker level, whether they be for a Conn 255/256 pairing, a Leslie 251 or set(s) of pipe.

[twnelson]

Both the rectagular 255 and the round 251 tone cabinet connectors on the box in the photo are line level outputs, as they feed amplifier inputs in either of the cabinets.

The Conn pipe speaker connector and switch adapter intercepts the output from the 'pulse' amplifier channel to the 6x9 speaker on that channel to feed the pipes in the appropriate switch positions.

--- Tom

[Hamman]

Both the rectagular 255 and the round 251 tone cabinet connectors on the box in the photo are line level outputs, as they feed amplifier inputs in either of the cabinets.

The Conn pipe speaker connector and switch adapter intercepts the output from the 'pulse' amplifier channel to the 6x9 speaker on that channel to feed the pipes in the appropriate switch positions.

--- Tom

By the schematic shown above it seems to show a speaker level signals ran to the connector boxes albeit tamed down with a couple of 150 ohm resistors.

[edkennedy]

I posted the schematic simply to give the connector pinouts. I do not know if the newer 644 also uses dropping resistors from the speaker outputs or gets the connector signals from the preamps.
Second notice; For those who have an old tube (valve) amp Conn like me, don't try to eliminate the resistors to make the connectors drive external speakers. The organ shuts off the external line level outputs by shorting them to ground. That works with the series resistors, will not work without them.
Third notice; Thanks again to AndyG for correcting my mistakes.

[twnelson]

On the 644 (and all solid state Conns with external tone cabinet connectors), the line level output signals come from switched line driver circuits fed from the preamp outputs.

--- Tom