Preamp to Headphone transformers?

I actually use a Stax SRD-7 that connects to the speaker binding posts of my amp. The SRD-7 allows me to switch between speakers and headphones. I have another device that allows me to do the same with dynamic headphones, but no switch so I have to swap the speaker cables between amp and the "box."

Would using the tape output of your preamp to a dedicated headphone amp would be an option?

Using whatever output isn’t the issue. It’s the voltage, as far as I’m concerned. 

I also dont have amplifiers in the traditional sense. My preamp is hooked up to my speakers directly because my speakers have built in amps (like monitor speakers). 

Turning my speakers on and off isn’t an issue. I would want a device that will let me use my preamp output to drive headphones. For that, I assume I would need a transformer or something to shift the voltage down while giving me either SE or balanced plugs for the headphones. 

In short, I have an excellent preamp (ARC Ref 6). Rated voltage is 2V RMS (balanced) to a 200 ohm load with a max of 70V RMS. This is just way too much for headphones, but it wasn’t designed for them.

First, the output voltage rating is based on a load of 200,000 ohms ("200K"), not 200 ohms.

Second, the 70 volt number is irrelevant, as the output voltage will be a function of the gain of the preamp, which is not particularly high; the volume control setting of the preamp; the output voltage rating of the source component; and of course the volume of the source material at any given time.

And while the combination of those factors may or may not result in too much voltage into the headphones, depending on the particular headphones, the much more significant problem is that the output impedance of the preamp (nominally 300 ohms single-ended and 600 ohms balanced, and probably significantly higher than that at deep bass frequencies) is much too high to drive almost all headphones with decent sonic results.

What you would need to accomplish what you are asking is some sort of active buffer stage that would provide a very high input impedance and a very low output impedance. Which might be doable, but it would probably be simpler and better to just buy a headphone amp and connect it to the tape outputs/record outputs of the preamp, as Clio proposed.

If you decide to do that, while I don’t know what the unspecified output impedance of the preamp’s tape outputs is, to minimize the possibility of impedance incompatibilities I would suggest choosing a headphone amp having an input impedance of at least 47,000 ohms (47K).

Regards,
-- Al

Thank you. I missed the k on the output impedance!

So that’s what been confusing me...my sennheisers are supposedly relatively high impedance at a whole 300ohms, but that’s not much compared to what the ref 6 is rated for.  I like the idea of the buffer stage that you discussed, because then I could just use the preamp to change volume. 

Hopefully something like that exists?