Vintage Japanese DD Consult and Suggestions Please

westcoast, JP Jones is a professional in the field of electronics. (I don't know exactly his degree level; he could be an EE or a physicist.) Until recently, he ran a business (Fidelis Analog) dedicated to the care and feeding of Technics DDs.  It was my good fortune that he agreed to look at my "broken" Victor TT101, where he found a trivial but near invisible problem (a crack across a tracing in a PCB hiding under a blob of solder and causing a maddening intermittent speed problem) that eluded several other smart guys, and he fixed it. As you may know, he designed and built a PCB using discrete parts that replicates the function of the unobtainable chip that governs speed of the SP10 and lower level series of vintage Technics tables, and yet is small enough to directly replace the chip in the power supply (MN8042 is the chip designation, going only on my memory of the alphanumberic code). Therefore, he was able to test performance of the tables to a level and using methods that I don't completely understand. I bought my SP10 Mk3 in NOS condition, and I did not need to replace the chip, but I did it anyway, because JPs PCB outperforms the OEM chip out at the 4th or 5th decimal place where it probably does not matter much. So I take his comparative analysis of the 10R vs the 10 Mk3 seriously.  He owns both.

Tomic, yes the platter is both a virtue and a potential Achilles heel of the Denon DDs. (If anything should happen to damage the tape glued to the inside rim of the platter, I think it's curtains for the TT.)

lewm, JP may substantiate this but I believe his chip replacement is for the SP-10 Mk 3 and the SP-15.  It is not a replacement for any of the SP-10 Mk 2 series.

Pryso, It was my impression that the MN6082 was used in the MK3 and in many if not all of the original 1200 series TTs, and probably the SP15, as you say, but I am not sure either way about the MK2. I would have thought it was also used there but could be wrong. I think JP has left the building but not on the irreversible path taken by Elvis, fortunately.

Aha! I just did a quick search.  Apparently the MN6082 was only used in Technics TTs that have variable pitch. That would not include the Mk2 but does include the others.

@laaudionut

I have a SP10 Mk 2, PD444, and LO7D and would add simply that all three are great choices.  Each will likely need to be re-capped if not already serviced.  All are satisfying in stock form, but will benefit with addition of modern footers and siting, re-lube, silicon nitride bearing, etc.

Overall the Luxman is probably the most satisfying in terms of reasonable cost, superb vintage esthetic, flexibility in adapting modern or vintage tonearms, and simplicity of maintenance/DIY speed adjustment as per factory service notes with a multimeter.  I found that its plinth design can be improved by substituting thick brass in place of the stock steel armboards.  For a further reduction in plinth resonance, I replaced the archaic stock RCA switch box attached to the bottom of the plinth with a solid wood subplinth that serves as a pedestal for a third arm base out front that accepts standard Micro Seiki cantilevered armboards.  All in all a great piece that is seldom discussed relative to other vintage DD.          

+1 for the Yamaha GT 2000 (L, X). HIFIDO in Japan has them available now and then. And they go through all of the electronics, motor, bearings to assure it is in top form, then double box with injection foam. I have A/B'd with a very well regarded JVC QL-A75 from that same highest Japanese R and D era and the GT is more transparent with finer micro/macro detail. Most all are Japan 100V. But the GT2000 has a DC port on the back to accept 24V dc. I had a power supply built to feed the 24V to avoid the internal power, but a simple step down works fine. It is not going to fit on every stand, and it weighs 61.73 pounds.

As Raul stated, the modern Technics are hard to beat. The SL-1300G is a very fine machine and it should fit the ascetics, but you will be hard pressed to find one for less than $3200. And based on the specs, I would be surprised if it could beat the GT2000.