Best Recto Tubes STR 425

I just scored a great looking 2005 Triple Rectifier 3ch head in custom black rhino covering with gold cloth front panel. Very low hours on it, the previous owner didn't play much. At first I was disappointed with the tone; it sounded kinda bland and one dimensional. This afternoon, I removed the original tubes (STR 440) and installed Electro Harmonix 12AX7 preamp tubes and Mesa STR 425 short base 5881 power tubes. What a huge difference! The amp sounds amazing now, super fat and incredible rich musical distortion.

This confirms that I really do not like the STR 440. I've tried them on several occasions and they just don't sound right to me. For best tone from a Rectifier series amp, I highly recommend the STR 425. I have them in a couple of my heads and they deliver the goods every time.

I'm betting that most of the improvements are from the EH 12AX7's, I believe that's the tube that Mesa was still using in 2005 (Russian-2). Just be mindfull of the cathode follower positions (V3 & V4) as the EH tubes do not handle the stress of those positions very well. If you notice volume dropouts I would replace those spots with JJ's (current Mesa 12AX7) or Shuguang (or any NOS/VOS).

What type of music are you playing, and is it alone or with a band? I find that what sounds 'full & smooth' when I practice alone, gets lost in the mix of the band.

Dom

I have not experienced any problems using the EH 12AX7 aka Russian 2 in cathode follower stages. I first changed the preamp tubes and did notice an improvement in tone. Then I changed the power tubes and that's when the amp really fattened up and became easier to play. I play in a pop/punk band, lots of chunky chords and palm muting. 25.5" scale guitars with PAF style humbuckers.

Hey man, I play similar type of music with a dual rec.

As far as v3 and v4 go, just keep an eye on your amp. If you notice anything funky with the volume as was stated before, just replace those Russian tubes as this has been a known issue with Mesa Dual Recs.

Enjoy it!

I loved the STR 420s, nothing has sounded as good to me since then

I have not tried the STR 420 but it appears there was more than one version of it... one had the old style shouldered glass possibly of Chinese origin... and another with small cylindrical glass and getter flash near the base, maybe Russian.

3124+ said:

I have not tried the STR 420 but it appears there was more than one version of it... one had the old style shouldered glass possibly of Chinese origin... and another with small cylindrical glass and getter flash near the base, maybe Russian.

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I think the ones I had were the old style, not positive though. I may have a single one laying around here somewhere.

If the STR420 is a coke bottle shape, with dual getter halo's on bottom of tube as well as getter flash near plate seams is a Chinese version 6L6GC. I had a quad of those in my Mark IV. Loved those tubes as they sounded very similar to the SED =C= 6L6GC if not better. The STR440 has a more throaty sound to them, they do well with the low end and still get the 3D complex harmonic distortion. As for the STR425, 5881 I am sure would sound better than the STR440 due to different impedance and frequency response. I will have to try out a quad of the STR425 in my Roadster.

I still have some 420 coke-bottles in my tremoverb (tubes, not the other 420 lol).
Yeah they're richer in the midrange than the str440 IMO.