ARC SP 9 MK III is the best and as all the SP9 uses two tubes , one for the line stage and one for the phono stage. MK III is the only one that uses 6922 the previous models use the 6DJ8/ECC88.
2 responses Add your response
I had the original SP9 and have upgraded it 1st to a MKII and now MKIII. If you have a need for a very good phono stage at a reasonable price the SP9 is ideal. The upgrade to MKIII GREATLY improves the line section too. It brings it more into the "LS Level" preamps I use it in a system with maggies/velodynes Audio RFesearch AMP and Theta Digital and VPI Jr