Does anyone here own a Jolida 202/302/502 amp

I bought my first tube amplifier 7 months ago. A MiniWatt N3
direct from the Manufacturer. I rolled the tubes with a Tung-Sol 12AX7 / ECC803-S Gold and a matched pair of Prefered Series 7189 from The little amp powers a pair of Energy CB-20 speakers. Everything sounds incredible. The amp is in the master bedroom and that's what turned me on the tubeaudio hifi.

Now my old 26 year old Kenwwood 100 watt KR 920 is getting
to the point where the electrolytic caps need replacing, mids and highs are distorted, volume potentiometer is getting noisy. So I figured I'd upgrade to a Jolida JD202s.
So I can get a good idea of well a stock Jolida 202s compares to a MiniWatt N3 I just swapped it out and hooked the Jolida 202s to my CB-320 speakers. The chinese 12AT7
flashed once like the old Mullards did at power on. I noticed one filament on the left 12AX7A glowing twice as bright as all the other preamp tubes. After warmup there appeared to be a very low 60hz hum in the left channel. This hum is not effected by the volume control so I think the hum is due to a bad tube and what I am hearing is signal from the AC heater line on the left side.
I started out by listening to Bruce Springsteen "10th Avenue Freeze Out". Horn section sounded amazing and I at first I was excited at how loud this little amp can drive my speakers.... next some Pink Floyd "The Great Gig In The Sky"... My little MiniWatt really delivers on the one.. The stock Jolida has poor imaging, the sound isn't warm for a tube amp. I'm hoping it's the Chinese tubes. Not enough Depth, and when the highs hit hard there's no headroom.
So, I've got an expensive amp that I have to tube Roll. I expected to tubroll my $189.00 MiniWatt amp. I did not expect to tube roll my $599.00 Jolida. So here what I have comming in. I figured the preamp tubes are where the tube imaging is lacking so I found a set of matched NOS Sylvania 12AX7 tubes. For the driver tube I decided to go with a set of GE 5965 tubes. it's compatible with the 12A7 but it has a slightly lower mu. I'm hoping to achieve more headroom from the lower gain.

I ordered a quad of cryo treated elecrto harmonix 6AC97 fat bottles to replace the EL34B tubes. I'm hoping this combination will sweeten the sound and get me a richer fuller sound.

Don't get me wrong, the amplifier still sounds better than my old Kenwood. But My little single ended 3.5wpc Miniwatt
demonstrated what tube hifi can sound like. I'm trying to get that sound quality, plus a little more power for my family room.

My question to the forum is is there anyone here that has experience with Jolida Amplifiers ? Did you do tube rolling and are you satisfied with the results you got.
I've owned a Jolida 202 for about 9 years now (in and out of different systems)and have never really liked until about 6 months ago when my local dealer suggested I change out the stock tubes. Also he suggested I drive it with a preamp, using it as a stand alone amp with the volume control turned all the way up.
I thought to myself I already have couple of nice preamps so I'll try that first before I dump a bunch of money on new tubes.
So upon arriving back at home I immediately connected it to my McIntosh C-45 preamp and boy what a surprise.....this combination made my Snell E-IIIs sing like they never sung before. Suddenly the little Jolida had some bass slam, smoother midrange, crisp highs, and imaging up the you know what! On some recordings the instruments seemed to float in space between the two speakers. In comparison driving these speakers directly with the Jolida using the same sources (Denon DP-62L/DL-160MC & Marantz CD-5001 CD player) the sound was harsher and lifeless with no bass definition. Believe it or not this was with the original stock tubes!
Unfortunately my Jolida is afflicted with the same 60cycle hum (mine is in the right channel) that you were experiencing and I have since pulled it lest risking any further damage. I tried switching tubes around but the problem stayed in the R ch.. Researching around the internet and talking to my dealer I understand the stock 202s use cheesy rectifier diodes and standard (cheep) filter caps. I suspect my issue with the 60 cycle hum is coming from the power supply section. One of these days I 'll dig into it and see what I find.
So that's my Jolida 202 story....try a preamp, you won't be sorry!
I am using JJ8803s Gold in the place of the stock 12AX7A
and a Jan Phillips 12AT7WC in place of the stock drivers.
Hum is gone. The flash from the right channel 12at7 is gone.
I paid $85.00 including shipping for this upgrade, well worth it.

For a hardcore performance test I played Mozart's Requiem.
The little Jolida 202a shook the house!
I got the tubes from I'm real happy with it.
I own a JOLIDA JD202A from late 1990’s and have roll the Chinese valves with JAN PHILLIPS 12AT7 (inverters), SOVTEK 12AX7LPS (drivers) and four 1999 SED Svetlana’s (“S” logo).
With this tube set, the amp sounded better, but dynamics and middle/treble extension was a bit shy, and dynamically, this set made the amp still a bit slow.
Than I read somewhere a review about ERSE MPX series capacitors, and decided to change the original block capacitors for these ones.
The “new” amp was completely different, having a stunning dynamics, pin-point imagery, with mids/treble on the bright side. Sometimes, depending on the record being played, that dynamics and bright treble seemed to my tastes somewhat aggressive. Bass was not too extended, but utterly tight, tuneful, making it very easy to follow bass lines.
That said, I went for a change on the driver stage, and tried a 5751 tube, this time from JJ TESLA, to calm down the things. First impressions are that bass is slightly less tight and tuneful, as well as imagery is slightly less focused (and these are, for sure, strong points of the SOVTEKs 12AX7LPS), and the above mentioned aggressiveness has gone (at least hearing the same records on same chain).
Old threads rule! I'm not shy about being a YUGE Jolida fan…I've been rolling tubes through my factory upgraded 502p for years now and currently use a quad of new version Gold Lion KT88s with NOS Mullard 12AT7s (6201 gold pin…amazing tubes), and new Gold Lion 12AX7s…an utterly tremendous amp.