Tubes....specifically JJs.

some_dude

Raging BB Gunologist
Would it be safe to say that JJs give your amp a stronger sounding fundamental frequency at the expense of top end complexity?

What exactly would be the difference in the way JJ's pre and power tubes 'dull' your tone?

If I were trying to tame an amp with 'too much going on up top' would I be best off running JJs pre, power, or both?
 
Re: Tubes....specifically JJs.

I think you actually verbalized the very thing I love about JJs tubes that I've never been able to figure out.

So yeah, I'd agree with that.
 
Re: Tubes....specifically JJs.

When I put JJ 12AX7's in my Marshall to replace the generic tubes in there, they added fullness and gain, but took away a lot of that 'sizzle' from the gain sound. I liked the improvement a lot, and I use JJ's now in my Mesa .22 and bass amp.
 
Re: Tubes....specifically JJs.

I don't think JJ power tubes dull the sound at all. They're very open sounding.
Svetalanas, on the other hand have a more buttery top end with more compression and mids. Svets will do a better job of rounding off the highs.

JJ pre tubes seem to be a little darker than many other pre tubes, so they'll tame the rattiness in the highs.

Essentially, if you had an amp that you were trying to make darker and beefier sounding, I'd go with Svetlana power tubes and JJ pre tubes.

Even still, it's just a slight difference. If you really want to revoice the amp, you'd be better off researching the right speakers for you. Speakers are more dramatic than tubes.
 
Re: Tubes....specifically JJs.

The preamp tubes are the one's that dull it, in my experience, and only the non-high-gain graded ones do it in a bad way.
 
Re: Tubes....specifically JJs.

I tried a JJ ECC83 in my Mesa.

A little background...I found my Mesa really prefers my Gibson and Epi LP. The Epi SG w/Iommi's just a lot sounded thinner at the same gain setting.

Installing the JJ preamp tube in V1 made the SG's tone from the Mesa sound really good. I suppose this is due to the match of a mid-rangey guitar with a mid-rangey peamp tube.

I would consider the JJ I tried to be more velvety-plush, with its tone concentrated in the middle. Resistance to feedback seemed as good as any other preamp tube I have tried. I think this tube could be nice in a shrill amp to mellow the tone.

Off topic: Personally, I am trying to clear the mud from my Mesa, and found a combo of Tung-Sol and EH 12AX7A preamps to be a good choice for my situation.
 
Re: Tubes....specifically JJs.

JJ both in pre and power filter some of the higher frequencies.

Now, where most see the greatest effect is in the pre tubes. In some amps they sound flat and dark, but in others they tame the ear peircing highs.

GJ said a key word, the rattiness. They can smooth out some rattiness.

There is a lot of difference in the ECC83S and the ECC803S, the first being much stronger in the mids, the latter being a bit more articulate.

Alot of complaints about JJ pre tubes come from people that use them in the entire preamp, which much of the time is not a recipe to a good sound.

If we were forced to have only one tube company, I would choose JJ's.

Edited for word usage.
 
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Re: Tubes....specifically JJs.

I don't think JJ power tubes dull the sound at all. They're very open sounding.
Svetalanas, on the other hand have a more buttery top end with more compression and mids. Svets will do a better job of rounding off the highs.

Hmmm.....The only 'Svets' that I've used are the New Sensor ones and I liked them. I've been meaning to try the Winged 'C' Svets for awhile now but haven't gotten around to it.

JJ pre tubes seem to be a little darker than many other pre tubes, so they'll tame the rattiness in the highs.

That's exactly what I'm after.

Essentially, if you had an amp that you were trying to make darker and beefier sounding, I'd go with Svetlana power tubes and JJ pre tubes.

I just ordered a complete set of JJs (12AX7, EL34 and 6L6)....if it winds up not working 100% I'll start experimenting with the Svets next.

Even still, it's just a slight difference. If you really want to revoice the amp, you'd be better off researching the right speakers for you. Speakers are more dramatic than tubes.

It's not a complete revoicing I'm after....just a general smoothing of the top end. I've had the same problems running through both EVM 12L and V30s (in open and closed back configurations).....too much 'stuff' going on up top to give me as smooth a sound as I'm after.

I tried a JJ ECC83 in my Mesa.

A little background...I found my Mesa really prefers my Gibson and Epi LP. The Epi SG w/Iommi's just a lot sounded thinner at the same gain setting.

Installing the JJ preamp tube in V1 made the SG's tone from the Mesa sound really good. I suppose this is due to the match of a mid-rangey guitar with a mid-rangey peamp tube.

I would consider the JJ I tried to be more velvety-plush, with its tone concentrated in the middle. Resistance to feedback seemed as good as any other preamp tube I have tried. I think this tube could be nice in a shrill amp to mellow the tone.

Shrill is a good way to describe my problem.

Off topic: Personally, I am trying to clear the mud from my Mesa, and found a combo of Tung-Sol and EH 12AX7A preamps to be a good choice for my situation.

I'm finding EH to have a bit too much 'something' in the top end right now. I'm hoping to find a mixture of them and the JJs that'll give me what I'm after. I almost bought a TungSol to experiment with but I don't have unlimited funds......

JJ both in pre and power filter some of the higher frequencies.

Now, where most see the greatest effect is in the pre tubes. In some amps they sound flat and dark, but in others they tame the ear peircing highs.

I have a couple of pre tubes and I've found the same. In a dark amp like my Orange they sound horrible.....it's like I threw a blanket over my cab and turned the gain knob down a couple of notches in the process. They do work well in my Mesa (MkIII....the amp I'm trying to tame), but they don't go far enough on their own.

There is a lot of difference in the ECC83S and the ECC803S, the first being much stronger in the mids, the latter being a bit more articulate.

Since it's a combo the ECC803S is not an option.
 
Re: Tubes....specifically JJs.

Yeah, screamin, i hear you about the fund$. I bought four EH's and four Tung-Sols (I'm not bragging...I have a sickness, and am a little p1ssed at myself for going ape cr@p on pre-tubes :eek13: ).

I find the 12AX7EH's have too much "presence"...too much peak in the ear, for use in all the positions. Another member decribed them as "toppy".

As it stands I like the Tung-Sol (a great/wide/open sounding/feedback-free) tube at both V1, and the phase inverter. I LIKE the EH's in V2 and V3. The only benefit of my tube buying insanity, is that I have two Tung-Sols and two EH's left over for the next retube in my preamp in the future.
 
Re: Tubes....specifically JJs.

Yeah, screamin, i hear you about the fund$. I bought four EH's and four Tung-Sols (I'm not bragging...I have a sickness, and am a little p1ssed at myself for going ape cr@p on pre-tubes :eek13: ).

I find the 12AX7EH's have too much "presence"...too much peak in the ear, for use in all the positions. Another member decribed them as "toppy".

As it stands I like the Tung-Sol (a great/wide/open sounding/feedback-free) tube at both V1, and the phase inverter. I LIKE the EH's in V2 and V3. The only benefit of my tube buying insanity, is that I have two Tung-Sols and two EH's left over for the next retube in my preamp in the future.

Cool. I was running a JJ in the V1 and PI and EHX in V2 & V3 right up until I melted the side of one of my power tubes......

.....no more experimenting until the new tubes arrive. :chairfall
 
Re: Tubes....specifically JJs.

I found using all JJs in the preamp of my Mesa combos made them way too dark sounding. I also decided that I like the JJ EL84, but prefer the SED/Winged C 6L6s and EL34s.

I'm kind of buying into Myles Rose's theory of "amplifier blueprinting", using the right tube for each socket position; so I have a mix of GT, EH, Mesa and JJ tubes in my amps.

Bill
 
Re: Tubes....specifically JJs.

Another thing about Mesa is that the fixed bias isn't always the optimal bias point, which causes some of that crossover distortion in the highs especially.
I heard a Dual Rec one time that sounded great and asked the player why his sounds better than ones I've plugged into before. He told me he had a bias pot installed, and the bias was set right on the money. I guess it makes a difference on those amps.
 
Re: Tubes....specifically JJs.

Another thing about Mesa is that the fixed bias isn't always the optimal bias point, which causes some of that crossover distortion in the highs especially.
I heard a Dual Rec one time that sounded great and asked the player why his sounds better than ones I've plugged into before. He told me he had a bias pot installed, and the bias was set right on the money. I guess it makes a difference on those amps.

I wonder how hard it would be to add bias pots to a Simul-Class amp?
 
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