EL844 tubes?

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Gear_Junky
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My Crate Palomino V16 uses a pair of EL84 tubes and years ago I read somewhere that using the lower output (if that's a correct term) EL844 tubes can be a way to get the amp to crunch sooner (or maybe I don't remember exactly, I just came across a set of EL844's in my box of things). But I've also seen tech guys say that it can damage the amp. Does anyone know? Thank you in advance :D
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andrewsrea
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I have no experience with the JJ EL-844. I would guess on how they made the tube 'lower power.' If they created an impedance mismatch or made the tube less efficient, that theoretically means the difference in output becomes heat somewhere (the tube plates themselves and / or the output transformer), or by having a very high internal idle current, which would stress the cathode caps and maybe the power transformer.

I am guessing your amp is too loud?
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Gear_Junky
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My amp is not too loud for playing with a drummer (maybe not loud enough), but for practicing on my own I was curious if I could max it out without damaging my drywall :lol:

I am asking all this from memory, I bought the EL844's many years ago when exploring this subject, only to end up going on a break from playing for all these years :)

Thank you for responding!
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JimyTheAssassin
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In general, tube gurus would say it’s good to find a tube with a balanced rating. If they’re rated like groove tubes (1-10), then the best tube is in the middle (5-6). The notion that it’s better to get a tube outside of that for one application or another is marketing to sell less than great tubes. I remember hearing that The el-844 was a gimmick to sell lower output tubes. It may be like @andrewsrea is thinking. I suppose the only real way to know is to get some actual measurements inside your amp.


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toomanycats
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I've got JJ EL844 tubes in my Peavey Classic 30. I put them in there about three years ago because I wanted to lower the volume for home recording purposes. The fact is, they didn't really lower the volume that much. Noticeably, yes, but it's not like it's half as loud.

As far as the tone, at first I didn't like them at all. They felt very stiff on the clean channel. The dirty channel was better, though it didn't bowl me over. So I actually let the amp sit idle for couple years. But about a years ago I joined a band and started taking the Peavey to practice with me. I got to really open it up a couple of times a week for a few hours at a time and this really seemed to make a big difference in the sound. I'm now really digging it.

As far as the bias thing, the Peavey C30 is supposed to be self biasing, though I don't know enough about amps to know if that's true or even means anything. I never did anything other than put the EL844 tubes in and play the thing. Haven't blown it up yet. :D

Here's a video demo I made of my JJ El844 loaded C30. I'm playing my Agile AL-3101M. Kinda weird to see Shawbucker when he was still a kitten, as he's all grown up now and the alpha male of the house.

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Gear_Junky
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Thanks guys, good input. So far I have enough to avoid using them, just doesn't seem worth it.
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JimyTheAssassin
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I would say the biggest difference in crunch/clean with tube placement will be in your pre-amp or to a degree the phase inverter. Still I wouldn’t expect a large change unless it’s from something like a 12au7 to a 12ax7

One caveat. I do have a 12ax7 that’s gone microphonic to the point that it sounds like a fuzz pedal with feedback. It’s pretty rad even if it’s signaling its final death. Sometimes you may find a tube that gives enough extra of what you need

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andrewsrea
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[mention]toomanycats[/mention]: For future reference, Peavey Classic 30's are not self-biasing and are a PIA to bias, having to futz with resistors. The Classic 20's and smaller are self-biasing.

[mention]JimyTheAssassin[/mention] I agree that 'rolling tubes' is a good way to find something you like. It is pretty cool you found a defective one that had a musical use!
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Gear_Junky
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I do remember experimenting with 12a_7 tubes with my SCXD and so still have a few of them. Back then I came to the conclusion that any change amounts to maybe a notch on the level/volume knob, so not really worth going back and fort, but that was with SCXD with its single 12ax7. I wonder if there's anything interesting to discover with my V16, which uses 3 of these 12ax7 tubes? I've always liked these amps, even if they're not like a Fender, so I'm not sure if trying to change it is even necessary for me.
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mickey
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Gear_Junky wrote: Sat Aug 22, 2020 3:01 pm I do remember experimenting with 12a_7 tubes with my SCXD and so still have a few of them. Back then I came to the conclusion that any change amounts to maybe a notch on the level/volume knob, so not really worth going back and fort, but that was with SCXD with its single 12ax7. I wonder if there's anything interesting to discover with my V16, which uses 3 of these 12ax7 tubes? I've always liked these amps, even if they're not like a Fender, so I'm not sure if trying to change it is even necessary for me.
The 12AX7 in the SCXD is NOT a pre-amp, it is a phase inverter.
Any amp that uses multi 12A?7 tubes has several preamp tubes & such.
You will always see more change swaping different 12A?7 tubes in an amp like that. :D
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JimyTheAssassin
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Gear_Junky wrote:I do remember experimenting with 12a_7 tubes with my SCXD and so still have a few of them. Back then I came to the conclusion that any change amounts to maybe a notch on the level/volume knob, so not really worth going back and fort, but that was with SCXD with its single 12ax7. I wonder if there's anything interesting to discover with my V16, which uses 3 of these 12ax7 tubes? I've always liked these amps, even if they're not like a Fender, so I'm not sure if trying to change it is even necessary for me.
Yup +1 @Mickey

First your name being gear_junky, you owe it to yourself to try these things out! Image. I think it’s a cheap way to feed your curiosity by rolling different preamp tubes. 12ax7 tubes can and do vary in their gain and character, even within the same manufacturer. The differences won’t necessarily be stark unless you find a failing one like I did. But all the same, sometimes the subtle differences do matter. YMMV

On the other side, For slightly lower gain, keep 12AY7 and 5751 tubes in mind.


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Gear_Junky
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mickey wrote: Sat Aug 22, 2020 3:11 pm The 12AX7 in the SCXD is NOT a pre-amp, it is a phase inverter.
Any amp that uses multi 12A?7 tubes has several preamp tubes & such.
You will always see more change swaping different 12A?7 tubes in an amp like that. :D
Mickey, I totally remember that from when you first said it to me all those years ago. But back then that's what I'd tried. Since I already have the tubes, I'm likely to try them at some point.

Thank you for the input, guys! :mrgreen:
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