How to extend a tube headphone amp with an output for a buttkicker amp?

[rock soderstrom]

Hi folks, I want to extend a tube headphone amplifier with an output for a buttkicker amplifier. (Ri>47k)

I don't know how to name this kind of transducer correctly in english. In german we call it Körperschallwandler, basically a bass speaker without its own membrane.

The idea is to split the signal (from my PC soundcard) directly after the potentiometer at the input of the HPA and then mix them together into a mono signal. (see attachment)

An adjustable lowpass would be cool, so that you can keep disturbing frequencies away from the buttkicker.

What do you think, can this be done purely passively?

If not, I would set up a summing amp with an OP amp and maybe another OP amp as a controllable highcut. (I am completely inexperienced in filter design).

How would you do that?

 

[abbey road d enfer]

Hi folks, I want to extend a tube headphone amplifier with an output for a buttkicker amplifier. (Ri>47k)

I don't know how to name this kind of transducer correctly in english. In german we call it Körperschallwandler, basically a bass speaker without its own membrane.

Buttkicker is a self explanatory name; most of us are familiar with it.

The idea is to split the signal (from my PC soundcard) directly after the potentiometer at the input of the HPA and then mix them together into a mono signal. (see attachment)

An adjustable lowpass would be cool, so that you can keep disturbing frequencies away from the buttkicker.

That's what I would do, because it would allow tuning the system easily.

What do you think, can this be done purely passively?

It could, but it would take many trial and errors to reach a satisfactory result, and it would not be versatile.
As I'm a lazy bastard, I would go for the active solution.