Jolida jd-502p

Try the GE TM gray plate 5751 from the 50s. The bass is prodigious in my experience and several friends as well. The Sylvania 2 mica Gray Plate 60s tube also has more bass than the RCA BP. As far as 12AX7s go you will prolly have to go with true Mullard Blackburn long plates "IF" you can get decent ones. They seem to emphasize bass. Failing that specific tube try any other older Mullard production.

Hi Wilson667

What 12AX7 or 5751 tubes did you get to replace the existing 12AX7 tubes in your JD-502p? Also is your JD-502P the stock or upgraded one from Jolida?

Thanks

Jedinite24
I am still not settled on what 12ax7 to use. Shortly after this thread my phono pre had to go to the shop. It was and still is my only source and does double duty as my preamp . I did not get to listen to any music other than through my tv.Now that it is back I hope to get this sorted.So for now I am using some sovteck 12ax7 the tung-sol that came with it and a rca jrc 5751wa of those I think I like the sovteck best.

I bought my 502 used here and the person I bought it from did not say if it was upgraded and I did not ask.So shrot of opening it up I have now idea how to tell.Sorry I could not be more helpful.

Is the Sovtek the LPS variant. Those have a good reputation for being clean and quiet with high gain. They are not known for their Bass however which is kind of interesting. Since it is a phono pre I think you may just be better off with carefully selected current production tubes. NOS tubes are just not plentiful enough to find really quiet ones, with a couple of exceptions like Upscale, new production tubes can be screened in large batches and thus as a rule can be super quiet. If you can afford them the GL reissues are getting some good reviews for their tone. They should still be less than really good NOS. Jim McShane over on Audio Asylum can set you up with good ones.

Mechans
Thanks for you response. The Jolida jd502p is a tube power amp, my phono pre is a PS Audio GCPH and is solid state.The sovtech I am using is an LPS and it came from the previous owner so I don't know if it is an early or a recent production tube.I believe I read somewhere that the ones from the eighties were the more desirable ones.