DIY spring reverb driver?

[floid]

Assume an 8ohm speaker. The schematic shows a pad network of a paralleled 15ohm resistor, a lamp acting as a current limiter, and the tank in series with the equivalent of a 6 ohm resistor...
These are all very small values relative to the typical output impedance of a line level device. I think this thing might want some juice.

It might be worth a shot to replicate the input pad shown, and hook it in parallel with the speaker of a low wattage amp. If this works, you'd then be looking for a way to eliminate the speaker.

[Drone]

What he said

You look at what originally was used to drive it, and extrapolate from there. Is your first statement confused? You say it has a 1.4K input, but your tech says it needs 4V ac into 1.5ohms??? 4V into 1.5 ohms is asking for 2.5W roughly, you won't get that from something that doesn't have a good amp, as in one that can deliver a bit of current. OTOH 4V in 1.5K is only 2.5mW that you could put a cheap LM386 in front of it.

Also in necklace spring reverbs, the orientation the tank is important, as the strings are slack, are you suspending it correctly?

[joninc]

I feel like I must not be communicating clearly - I am not trying to use this with instruments through an speaker but you are suggesting I build that and then subtract the speaker?

I'm now wondering if the AO-35 is only the amplifier for the speaker and not necessary to drive the springs...

Basically the gist of it is that I have a necklace spring and want to use it as a outboard fx unit so I'm trying to determine what is needed to make that work. I had hoped that the Tank Driver would be enough but apparently it is not.

[floid]

The lower left portion of the schematic provided indicates "input to reverberation unit" is connected to "signal from console speaker." You likely need something that provides a speaker level signal. You can then "fake" the speaker with a dummy load. It's not just an impedance issue, it's a level issue.