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My Experience with a Jolida 202s (SoFar..)

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Tube Rolling a Jolida 202a

Hi,
I bought a Jolida 202a to replace my 26 year old Kenwood Amp. It appears that the 12AX7A that ships with the Jolida amp is too bright and edgy to the point of almost distorting. To give you an idea, it makes your good recordings sound like a low bandwidth mp3 file. I swapped my miniwatt N3 in place of the Jolida. The 3.5wpc minwatt may not go as loud, but it certainly sound better, the sound is much fuller, better frequency response, I have a NOS sylvania 12AX7 and 2 7189 preferred series output tubes that I bought from the tubestore in the miniwatt. I swapped my vintage NOS 12AX7 out for the 12AX7A that was in the Jolida. I was able to verify that's where the terrible "nails on the chalkboard" was coming from. So I ordered Sylvania 12AX7 tubes, GE NOS 12AT7 Drivers, and a Quad of cryo treated 6CA7 Electro Harmonix fat boy tubes. I'm hoping the warm the sound up a bit, get better imaging, broader frequency response.

Maybe next time I'll just attempt to build one from scratch, this way I use the resistors, caps, potentiometer, tube sockets, and tubes that I want.

Have any of you here tube rolled a Jolida and was satisfied with the results ?
 
I wanted to post this so anyone looking to get a Jolida 202s would know what to expect. Maybe this post will save the some money.

If you are used to the sound of a tube amplifier, such as myself, you won't be initially impressed with the sound. If you are not, well it sounds like a decent solid state amp when you get it. Initially I started emailing friends looking to see if they had any old 12AX7 and 12AT7 tubes for the preamp and some old 6AC7 output tubes. No luck. Instead of hooking it up to the stereo rack in the family room (the initial purpose of the amp was to replace my 26 year old Kenwood) I set it up in the bedroom, taking the place of my MiniWatt N3 for now. I figured it couldn't hurt to give the tubes a burn in. I also bought a matched quad of EH 6AC7 output tubes, NOS matched pair of sylvania 12AX7 and NOS matched pair of GE 5159 online. I decided to go with the 5159 due to the lower mu than the 12AT7. Initial impression of the Jolida 202 was it needed some head room, so I I wanted to reduce the driver gain a little. I figured a little less is more.
I also ordered the matched pair TungSol 12AX7 and matched pair Phillips 12A7T online. I guess I really shouldn't of jumped the gun and ordered all of these tubes. The factory tubes started to sound great after the second week of use. As I was working out the bass deepened and the sound stage opened up! I was listening to the Todies (Grunge) while I was working out. It went from lack of bass and sound stage to .....WOW!
After I worked out I had to verify the drastic improvement in sound . Pink Floyd - "Great Gig In The Sky" sounded amazing. All the detail you would hear with decent headphones was there playing through my speakers.
This was one one of the song in my test audition set, and there was
no depth, and I couldn't hear all the detail that I do now.
My Blues collection really sounded great too! Horns. Sax, Bass, Harmonica, Guitar, Vocals, Cymbals, all good! and with depth! The only thing that can use tweaking is taking the edge off of some of the highs, then again my sound source was an iPod. I don't have my CD player or Turntable upstairs.I think that means all I really had to do was replace the 12AX7As with some decent ones. I am really liking the sound of this amplifier now! I tested with Tchaikovsky's 1812 Overture at 75% Volume. All I could say is WOWWWWWWWW!

"Bar Room Boogie" sounds amazing on this thing!

My advice to anyone that buys a new tube amplifier. Give the stock tubes at least 40hrs burn in. The amp won't sound like it's the best amp you heard until the tubes burn in.

I emailed marc at Jolida and recommended that he burns in the tubes before he ships the amplifiers out. This way hecan get a Wow factor instead of the email I sent stating "WTF my little 3.5 watt SE amp sounds better!"

It sounds so good that I'm not gonna move it to the family room for a month or two!
 
ok... My first tube upgrade arrived. 2 JJ ECC803s gold and 2 jan phillips 12at7wc tubes for the preamp. WOWWWW! I don't know if I am going to need to upgrade the output tubes. The sound is amazing!. If anyone is buying an amp like this Jolida I would say JJECC803s and 2 jan phillips 12at7wc for the driver. I really like the way it sounds now.
 
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I have 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 on the 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 downs 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).
One of these days I’ll try the SOVTEK 5751s, said to be constructed the same way as the LPS’s.
 
I have 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 on the 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).
One of these days I’ll try the SOVTEK 5751s, said to be constructed the same way as the LPS’s.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.