I've got a modded 502b and have tried 5751s, Mullards Russian, Phillips etc. in both ecc81 and ecc83 apps. What I finally settled on were Tungsram for both positions. Very neutral, good highs,bass came on nicely after breakin and smooooth.
Modded my Jolida 302a tonight, WOW
I purchased a used Jolida 302a from a friend, as I wanted to discover tubes and figured an entry-level integrated would be a safe, fun place to start.
When I got it from him, it was pretty much stock / factory except for Svetlana EL34 tubes and he had had the balance control eliminated.
Well, this evening I decided to get gutsy and got out the screwdriver and put her on the operating table. My goal (and end result): elimination of the source selector and rewiring the inputs directly to the volume pot. A little soldering and such later, I took one of the pair of 4-conductor shielded wires and removed it, using the remaining one for separate runs for signal and ground on the left/right CD RCA jacks, tying the shield in with the ground only at the volume pot. I then buttoned it back up for a listen.
OH GOOD LORD!!!
What a stunning difference. That little source selector had TONS of crosstalk before (you could be on AUX and still hear CD pretty darned clearly for example), I figured it was a train-wreck in the signal path, and this confirmed my suspicions -- the difference was absolutely night and day!! I was blown away by how much better the stereo separation was as well as the width of the sound-stage (the track "The Trees" off the Spirit of Radio (greatest hits) by Rush was incredible, it opens with birds and such, and they seemed quite enveloping).
So this has me thinking, well, how badly is the quality of the (chintzy looking) volume pot affecting things? And if I can replace it, I wonder if I could put in a remote controlled one such as the ALPS I've read a bit about recently? Has anyone had experience with this or other fun DIY mods for the 302a/b? If so, please do share ;) Now all I need is some good pre/driver 12AX7/AT7 tubes... I'm leaning toward the Mullards for the AT7s but I haven't yet decided on the AX7 tubes, probably start with some Electron-Harmonix and work my way up / over from there...
When I got it from him, it was pretty much stock / factory except for Svetlana EL34 tubes and he had had the balance control eliminated.
Well, this evening I decided to get gutsy and got out the screwdriver and put her on the operating table. My goal (and end result): elimination of the source selector and rewiring the inputs directly to the volume pot. A little soldering and such later, I took one of the pair of 4-conductor shielded wires and removed it, using the remaining one for separate runs for signal and ground on the left/right CD RCA jacks, tying the shield in with the ground only at the volume pot. I then buttoned it back up for a listen.
OH GOOD LORD!!!
What a stunning difference. That little source selector had TONS of crosstalk before (you could be on AUX and still hear CD pretty darned clearly for example), I figured it was a train-wreck in the signal path, and this confirmed my suspicions -- the difference was absolutely night and day!! I was blown away by how much better the stereo separation was as well as the width of the sound-stage (the track "The Trees" off the Spirit of Radio (greatest hits) by Rush was incredible, it opens with birds and such, and they seemed quite enveloping).
So this has me thinking, well, how badly is the quality of the (chintzy looking) volume pot affecting things? And if I can replace it, I wonder if I could put in a remote controlled one such as the ALPS I've read a bit about recently? Has anyone had experience with this or other fun DIY mods for the 302a/b? If so, please do share ;) Now all I need is some good pre/driver 12AX7/AT7 tubes... I'm leaning toward the Mullards for the AT7s but I haven't yet decided on the AX7 tubes, probably start with some Electron-Harmonix and work my way up / over from there...
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- 6 posts total
- 6 posts total