Hi all,

I have been using an Aric Audio preamp to drive my Torii MK IV.  It is a good combination and both amplifiers use point to point wiring, good parts, simple circuits and VR tubes.  The preamp has a pair of 60s Bugle Boy 12AU7s and is nice and transparent.

I have never used a tube pre before this.  I have also never used a preamp with a gain control and a volume control. I noticed right away that the signal distorts if the gain is too high.  My approach has been to set the Torii's volume at around 80%. The volume control on the preamp is a motorized Alps.  That ends up at about 40% when I back off the gain so there is no audible distortion (to my ears).  

I have read plenty about riding the gain here. My summary is try higher input levels to the Decware amps and see if you like the sound better. I have little experience with setting gain on a pre however.  Is this similar to a bias control on amplifiers.  Higher gain = higher tube bias?  Should I aim for minimal gain on the pre?

What approach would you guys take? What should I listen for?

This isn't a big problem, the system sounds amazing, but I want to learn more.

-Karl

Gain riding/ structuring is a great tool to enhance the sound of your system.   It’s subjective on what sounds good to you based on your system.  In my system…I max out my DAC to 4V via the XLR’s into my ZBIT when I am using my Tori MKIV.  With my pair of Zen SE84C+ that are configured as mono’s, I dial back the ZBIT to 80%.  When the signal hits my CSP2+, I generally like to run that higher and my amps lower….but that sometimes depends on which preamp tubes I am running.

Like Lon says..you just have to play around with it until you find what sounds good to you.  Running the preamp high and the amp lower, and vice versa will give two different distinct sound signatures.  Good luck and happy experimenting!