EL84 Tube Review

andrewsrea · Sat Jan 29, 2022 6:56 pm

Just wanted to share my EL84 tube experiences. I recently got to try a bunch.

First if you have an amp with uses EL84 output tubes, the cathode-biased ones can be brutal on them. For me they tend to not last as long as the fixed-based 6L6, 6CA7 or EL34 tubes.

I use this tube set in a Supro that I converted into also being a Vox AC15 type amp.

My favorites were a set of Groove Tubes from the early 90's which were made in the Ei factory in Yugoslavia. They are tired now, but still sound better than some new tubes. They have a '7' screened on them and if you ever find new ones - buy them!

Here are some more I've tried, some recently:

Tung Sol EL84: I just got a set and they are staying in my amp. Better headroom than most and a good mix of creamy and crunch. Bass is tight and present, mids are clear and the highs are chimey without being strident. They bloom when pushed and have a lot of tonal range. Tung Sol is an Electro Harmonix (EHX) brand, made in Russia supposedly to exact specs and their best recipes.

Preferred Series 7189 tubes: Borrowed from my neighbor, these are the exact same tube as the Tung Sols. Side-by-side the have the same construction, they tested exactly the same on my EICO 666 and they sounded exactly alike in my amp. I am guessing these are rebranded by EHX for the Tube Store, who guarantees them for high voltage.

Mullard EL84: Another EHX Russian made to original specs. They do not have the headroom, crunch, lows or chime of the originals. They have a nice creamy, early bloom distortion. Their mid-range makes them sit nice in a mix and early distortion would be good for a bedroom player.

JJ EL84: If you can find a new set from the very early 1990's- these are very nice Tesla tubes. Due to the wars in the Slovakia regions since then, they've moved around. Lot of reports of poor reliability since then. Some I've used sounded initially great and faded fast. These and Shugang tubes are more likely found in a new OEM amp. I have found JJ tubes to be bland.

Shugang EL84: Probably the most commonly found EL84 out there. Nothing particularly special tone wise and reliability is pretty good.

Gold Lion N709/EL84: Don't by these! I bought a set for my best friend's birthday and loaded them into his newer Vox AC30. With very little use and no abuse, 3 out of 4 blew up and took out screen and control grid resistors. They were very expensive and when they worked, I did not hear any magic.

yesca · Sat Jan 29, 2022 8:43 pm

Nice review, brother.

Partscaster · Sat Jan 29, 2022 11:13 pm

Thats a valuable comparison. Thank you andrew.

mozz · Sun Jan 30, 2022 1:57 pm

No russians? 6P14P. 70's -80's production. They were plentiful and fairly cheap a few years back. Seems to have gone up in price. I should torture test a few and see how much higher than 300v they can take.

andrewsrea · Mon Jan 31, 2022 11:43 am

mozz wrote: ↑Sun Jan 30, 2022 1:57 pm No russians? 6P14P. 70's -80's production. They were plentiful and fairly cheap a few years back. Seems to have gone up in price. I should torture test a few and see how much higher than 300v they can take.

The Preferred Series, Tung Sol, Mullards, Glod Lions and Electro Harmonix El84's (I did not review - but should have) are all Russian made.

For the 6P14P tubes, are they NOS?

I've never come across them,but heard about them.

jtcnj · Mon Jan 31, 2022 2:04 pm

I have a Marshall type 18w cathode biased amp build with mostly VHT parts from that Ubuyguitars thing years ago. I have tried 5 or so different brands. New JJ and an unbranded made in China, and some used / test good Sylvania and the Russian 6P14P and 6P14P-EV.

I really cant tell much difference between them.
Maybe its just my hearing or the amp.

andrewsrea · Thu Feb 03, 2022 12:17 pm

jtcnj wrote: ↑Mon Jan 31, 2022 2:04 pm I have a Marshall type 18w cathode biased amp build with mostly VHT parts from that Ubuyguitars thing years ago. I have tried 5 or so different brands. New JJ and an unbranded made in China, and some used / test good Sylvania and the Russian 6P14P and 6P14P-EV.

I really cant tell much difference between them.
Maybe its just my hearing or the amp.

Sometimes that is the way it is with amps. I found the more complex (more parts) an amp or pedal is, the less a single component changes the sound.

My amp described above is one I build from a yard sale Ward amp as a donor. It is a very simple 1/2 12AX7 drive into a treble-bass tone stack, into a 1/2 12AX7 recovery, into a 12AX7 short-tail inverter-driver, into the EL84's into a very efficient Vox Blue 12" 25w Celestion. It has a switch to add or eliminate negative feedback (tight with a presence control or loose response w/ no presence) and a switch to change the cathode bias for EL84 output tubes or 6V6. It has a harmonic tremolo driven by a 6AU6 which simply adds and subtracts dc voltage to the EL84 control grids.

Very Voxey and not high gain. Somewhat sensitive to component changes.