Audio research

This is what you need.

http://tubes4hifi.com/pre11.htm#PH16

Thank you Elizabeth obviously you understood my question.I know there is no contest between a reference audio research and a sp9,just wanted to get some input on the two units, its just going to be a trade between a couple of old audiophile buddies ,I,m not spending a cent or will I take a lost at all.He will just take it back if its not to my liking and sell to someone else with one phone call.I am sure it will sound fine I have great speaker cables  power cords interconnect vintage 6922 tubes to try out to hear what works best.I do have a question about the faceplate it looks like a newer one compared to the 1st couples of years.The faceplate looks just like my ls3 accept with the added phono .Would you know which year that unit might have been made,it really does look like brand new mint out of the box.Thanks MAXWELL

 There were a few different versions of the SP9. It should say on the back if it is a mk2 or later. If you email ARC with the serial number, they can tell you what version you have and when it was made. Around 1990 or so ARC stopped putting mounting holes in the face plate.