I bought a 1960's collins broadcast mixer that had 9 very big tube mic pre's. I had them racked with phantom power by a gentlemen who really knew his stuff. He worked with Bill Putnum and Bruce Swedien, and he had his own company called studio technologies. He manufactured their own version of the EMT plate after it's patent ran out. He put know gain contols or pads on these oh so quiet pre's. He told me to use the pads on the mics and the hardware gain control in protools. The output is so hot that I have to drop the input in protools down -24db even with a -10 to -20 db
pad on the mics. For dynamics i use the shure variable pads down -20 to -25 db.
Anyway's, I've heard good thing about the RCA's and I'm sure you could rack them and end up with a big smile like I did after I got the big collins console.