Preamp tubes in the Epiphone Valve Jr. head - Is There Tone in Holland?

The Epiphone Valve Jr. Head , or simply "Valve Jr" as we like to refer to him, is a wonderfully scrappy little guitar amp. Originally $99, but now $129, the Valve Jr. head is a 5 watt, Class A, all tube guitar amplifier. It has one knob - Volume (Steve Jobs would be proud), and two tubes, a 12ax7 as the preamp tube and a single EL84 for power. There are 3 speaker outputs, 4 ohms, 8 ohms, and 16 ohms; which is an amazingly nice feature to have. This simple little beast is great fun, and Kevin and I decided to do some tube swapping the other night. We've always been skeptical of the real differences in tube sound, and we wanted to test it out ourselves. Although obviously built to a price point, the Valve Jr is a surprisingly noise free and quality guitar amp, and its simple circuits and design really highlight changes in tubes.

For our tests, we used the Valve Jr plugged into the speakers from Kevin's Silverface Super Reverb - 4 10 inchers. We used the same guitar, a nice Stratocaster built from AllParts parts. The pickups are Fender 57/62, and the neck is maple, strings are .11 gauge.

First up was the stock tube, a shiny new Sovtek 12Ax7. It has only had probably 10 hours of use, so it's almost new for all intents and purposes. The Sovtek has a wooly sound, with a pronounced lower midrange. It gives the amp a decidedly "British" tone, being forward with the mids, and laying off some highs and lows. It was medium-hi gain. Overall it was ok, but not exceptional. It certainly has a "tubey" sound, almost as if Epiphone put it in to ensure the Valve Jr sounded nothing like the solid state and digital amps it competes with price wise.

Next up was an Electro Harmonix 12ax7. This had been used some, but exact age and mileage are unknown. Surprisingly, this played and sounded almost identical to the Sovtek. Same pronounced midrange, wooly low-mid, and medium high gain. I know some tubes are manufactured in the same place and simply rebranded, and I wouldn't be surprised if these two were brothers, or maybe cousins.

Following was a G.E. 12ax7. This was snagged from an old Magnatone amp, so it had plenty of use, but displayed no microphonics. The first thing we could tell with this tube was that it cleaned up and shined the Valve Jr's wooly midrange. Gone was the midrange forwardness, and replaced with lots of high end. With the single coil, vintage strat pickups we were using, it really brought out the highs and gave us a shimmery sound. It wasn't hard or shrill, just very clear and open. Given the Class A operation, we weren't surprised to notice this tube gave the Valve Jr a bit of the Vox vibe. Vintage, but clear. Gain was lower than the first two; medium gain.

Next up was a Telefunken 12ax7, also stolen from the Magnatone (that bastard has like 15 tubes or something). The midrange stood out as very clear and buttery. It was not as brilliant or shimmery as the high end of the GE, but still clearly better than the E.H. or Sovtek. It was medium gain, and displayed a nice round tone, but it simply didn't have the harmonic overtones or detail of the G.E.

Following the Telefunken was a Mullard 12ax7 from, you guessed it, the Magnatone. Kevin and I didn't really expect much, assuming all the hype around Mullard tubes was just that; hype. Wow. First thing we noticed was high gain - it was significantly louder than any of the other tubes. But, it seemed to breakup later than the Sovtek or E.H., which was interesting. The sound was phenomenal; it didn't have the crystalline highs of the G.E., but bettered every other tube in nearly every way. Single notes rang out with harmonics and overtones, sustain was great, high notes were buttery and clear. Chords were fat, but retained definition. It was simply exciting to play, subtle dynamics and playing just brought out more and more. Excellent tone for "hot" sounds, like blues or rock. Seriously impressive.

Lastly, we found a Real Life 12dw7 in the Magnatone. Now, this isn't a 12ax7 like the others, but we gave it a go anyway. First impression was that this made the Valve Jr. an almost bona-fide jazz amp. It was much lower gain than the other tubes, and had a very hifi sound -- clear strong highs and lows, and less midrange push than the more guitar oriented tubes. Very smooth and rounded on single notes, and a fat thunk to chords. Almost no break up, even cranked up. Very interesting, and a great tube for coaxing cleaner tones out of the Valve Jr.

So, what we discovered was that we were plain wrong about tubes being inconsequential in the overall amp tone. Different tubes made a huge difference. As far as a favorite, the Mullard probably wins overall for plain excitement and tone. The G.E. had a beautiful high end that gave a gorgeous vintage tone, and was a close second, and a little more restrained than the Mullard. The Real Life 12dw7 was a clean tone monster, giving a surprisingly jazzy and clear tone to the Valve Jr. The Sovtek and EH were simply outclassed, and sounded cheap and forced in comparison. The Telefunken was somewhere in between the "top 3" and the "bottom 2", but wasn't as impressive as we were expecting. 

Notably absent from this test were a couple tubes. For one, we used high end old tubes, and cheap new tubes. A newer, higher end tube like a JJ is a must-test. We also want to test the new reissue Mullards, just to see if they capture any of the magic. We'd also love to try Bugle Boys, as they're fabled as much as Mullards and Telefunkens for tone. 

The Valve Jr. is simply great fun, and a great way to try different tubes and options with your gear setup. At $129, or less used, it's worth it to pick one up. You'll have fun.