Are there passive attenuators that don't zero volume and only offer one input ?

Are there passive attenuators that don't zero volume and only offer one input ?

You've just described the Lightspeed Attenuator to a tee.

Cheers George

This sounds like something I could use but it would need to have XLR ins/outs. My preamp has two "pre out" pairs: one RCA, one XLR. The XLR are 2-volts hotter than RCA so would be louder if trying to bi-amp. 

Sure, Khozmo and Hattor. I just recently received a Khozmo dual mono passive attenuator with separate left/right channel volume adjustment, one input, two outputs (one for subs), all balanced XLR ins-outs, display, and remote control of all functions. I use it for remote volume adjustment in conjunction with a unity gain buffer. Discrete resistors with Takman REY metal film shunt resistors and a Vishay "nude" Z-foil series resistor.

Placette passive. 

Goldpoint
https://www.goldpt.com/
https://www.goldpt.com/goldpoint_passive_preamps.pdf