RD50 tone! JRC4558D 5751 change!!

I am kind of a lurker on the site but I thought I'd brag about my amp and some stuff I have done.
I replaced my pre amp Op-Amps with the Tube Screamer TS808 chip, the JRC4558D, instead of the stock TL072 and used the 5751 lower gain hi spec tube.
It smoothed out the distortion channel and made the clean cleaner but with a full harmonic growl on full chords to a nice bluesy breakup after 4.
I like the amp at low volumes clean with bass up high (8) and treble at 5-6 or even add the brightness. It sounds like a respectable volumed Twin Reverb with lots of dynamics, punch and feel.
The distorion channel needs to be played loud to sound great and with less bass and more highs. At lower volumes it is raspy if much past 3. To solve that put in the ear plugs and turn it UP LOUD!
I also use a Fender repro fotswitch which I added the LED to. It pops some when switched but I am over that already.
BTW I am using a Weber Jensen voiced Signiture Series proto type speaker that I got from Ted. I tried a Hellaton Celestion G60H and it was great loud and it took on a more Brittish high gain thing. I went back to the Fender thing. That is what a MM is to me. I also use this for Harmonica and I can get a decent Chicago wail out of it. It is actually a nice horn tone with a custom mic (with a vintage crystal element) slamming the front end.
Very versitile!! Yes my '64 BF Deluxe and my '63 Blonde Bassman are nicer but this is the one I haul to the jams and shows. Light loud and replacable if damaged or stolen.

I've also swapped the jrc 4558 chip for the TL072 and I agree it's better sounding. What brand of 5751 did you use? Do you know which version of the RD50 you have? Do you have one of the later models with the mid-shift switch?

I'm also interested in what brand 5751 you used, wrongdog. let us know, bro.
ed

Sorry I have not checked in with the board in a while...
I use GE and Sylvania 5751 tubes. The GE "five star" are great tubes. Super well built and affordable. RCA branded ones are slightly better but cost a ton. These are also great for combos since they are super rugged and have very low microphonics inherant in high power small combos (like the Peavey Classic 20/30/50 tube eating machines!!). The GE is a triple mica construction and best all around value. $12-30 on eBay. used or NOS.

Oh! I forget about the version but I think it is the middle one before the mid shift version though.

Hi all, The JRC4558 sound great and the LF 1458 dinasaur IC sounds pretty sweet too! You can mix these up for a different combination. I found a BB 2107 and it sounds super in the front and 4558 after. The 4558 sounds smooth and the 1458 is slightly less gain and has a sweet mid/top to it, slightly less lows. The fancy hi tech botique IC's sound pretty sterile to me, but some of the late 70's-early/mid 80's opamps sound great!