DIY inline attenuators, XLR
my friend made me a couple... soldered some high quality matched resistors inside xlr neutric interconnect.
I gave him the output impedance of the cdp, (low] the input impdedance of the power amp, (high)
and he managed to match the series and paralell resistor values so that they are ok with the system.
contrary to the rothwells, these cables are my best preamplifiers... nothing sounds better in the home.
Of course its not convenient to change volume..
I got them built to hear my cdp without the interference of a preamp.
I have a couple. - 30 dB attenuation is my favourite, gives a reasonable volume direct from cdp to power amp.
I have a couple of other attenuation values...-20, and -34 which I havent even tried yet, it is a very high attenuation.. almost a mute..

I think, its not really rothwells fault, it seems the benefit of these things highly depends on how they match the source and load electric parameters