Tubes Tubes Tubes


When it comes to guitar amplifiers, it all starts with the tubes. And the speakers. And the Circuit. And the guitar. And the guitarist. You get the idea, there’s a lot of things that affect your tone, and you should never overlook the tubes you’re using in your amplifier.

I recently had a lot of issues with tube reliability using JJ EL84 tubes. They sound good, but a large percentage of them came to me with a defect: the light-bulb effect shown here: Some people say it’s okay, others say it’s very dangerous and can eventually/potentially destroy transformers. I’m not interested in taking the risk either way.

To compare the tubes, I took a good pair (no flash defect) of JJ tubes, and put them up against the TAD EL84-STR and the Tung Sol (reissue) EL84-TS. The test amp is a JMP Guitars 18 Watt EF86 “TNB” (not to be confused with TMB).

Check out the EL84 output tube comparison video hero:

Check out the EF86 preamp tube comparison video hero:

If you’ve watched any of my videos, or seen any of my other comparison tests, you probably know that I’m not a fan of hype. I also don’t spend a lot of time worrying about what people say is traditionally done. At the end of the day, we need to listen to our own ear, and how it affects the way we play.

Note: I ordered the three sets of tubes for this at the same time, the JJ set came with 1 defective tube that was replaced with a good matched tube. Out of the last 10 pairs of JJ EL84 tubes ordered this year, I’ve had 7 or 8 defective individual tubes (1 per pair). All defective tubes were sent back, and then the defective replacements were sent back, until finally that last tube was replaced and my frustration level eventually led to this video. :)

I realized that I needed to remove the inconsistency of the “human” component in the test after comparing capacitors in one of my other videos. So I played through a loop pedal and recorded some chords to compare the tubes at different output levels, with different playing styles. The loop pedal output is all that is heard on the demo, to keep everything consistent and get a true comparison. Essentially, nothing was changed from sample to sample besides the power tubes.

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