Wow! that was really interesting. Before I purchased my REF 3, I retubed my SP-11 MKII with AR supplied tubes and I have to tell you I with several of my friends over about a week compared my borrowed REF 3 (dealer demo) with the retubed SP11 MKII and several other borrowed pre-amps from the dealer, including other AR pre-amps and the re-tubed SP11 MK II held its own quite nicely. We were hard pressed to hear major jaw dropping differences. There were differences and the REF 3 ultimately was a better pre-amp, but blown away? not close. Also, the re-tubed SP11 MK II actually was better than the newer AR pre-amps in our opinion. I tried hard to justify purchasing the REF 3 and made up many excuses, but keeping the SP11 MK II would not have been a mistake. I wanted a remote control pre-amp (getting lazy) and compared the SPII with several remote control units and not one justified the huge increase in cost. Not even the REF 3. I bought it anyway and it is great, but I really didn't need to do it. The gentleman that I sold the SPII to loves it also. I would say, re-tube the pre-amp with proper tubes from AR before getting rid of it. In my opinion, with all respect to Elizabeth, it is still one of the best out there. Re-tubed.
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