|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 tubestore.com. 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.