JJ E34L. Next best thing to Bias Mod

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ochrisl

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So I got my bias mod kit and I figured I would take some before readings. With Mesa STR 447 stock tubes the highest reading I got was 19.5 ma. Thats with Bold Power,silicone diodes and 50 watt on channel 2. Spongy knocked that down to about 9. That's pretty darn cold for a tube amp.Just for fun I threw in some Electro Harmonix EL34. At the highest setting I got 24 Ma. A little better. So I had some JJ E34L's handy that had a '45' on the box. Those registered a warm and fuzzy 38.5 Ma. Kicked over to channel 1 crunch and it was about the same. Switched to fat clean and it went up to 44. (remember the 45 on the box :wink: )
So if you don't want to do the bias mod but want to open the amp up a little to where a tube amp should run get yourself some JJ E34L's and specify a grade of 45. You can get other brand tubes in various grades of course if you want to experiment. If your lazy just order these from someplace like Eurotubes and pop em in. I would recommend getting the bias probe they sell so you can see wht your actually running at for experimenting and making sure your not running to hot.
 
Thats the philosophy of Bob at Eurotubes. Select the tubes to bring the amp up to the proper level. good stuff
 
ochrisl said:
So I got my bias mod kit and I figured I would take some before readings. With Mesa STR 447 stock tubes the highest reading I got was 19.5 ma. Thats with Bold Power,silicone diodes and 50 watt on channel 2. Spongy knocked that down to about 9. That's pretty darn cold for a tube amp.Just for fun I threw in some Electro Harmonix EL34. At the highest setting I got 24 Ma. A little better. So I had some JJ E34L's handy that had a '45' on the box. Those registered a warm and fuzzy 38.5 Ma. Kicked over to channel 1 crunch and it was about the same. Switched to fat clean and it went up to 44. (remember the 45 on the box :wink: )
So if you don't want to do the bias mod but want to open the amp up a little to where a tube amp should run get yourself some JJ E34L's and specify a grade of 45. You can get other brand tubes in various grades of course if you want to experiment. If your lazy just order these from someplace like Eurotubes and pop em in. I would recommend getting the bias probe they sell so you can see wht your actually running at for experimenting and making sure your not running to hot.
Click to expand...


yep. that really explains why my Ace sounded pretty underwhelming with the stock tubes and excellent with a graded Hot set of tubes. BIG difference. It really makes me question what the hell Mesa is doing by knowingly castrating their amps like this.
 
inkwachemis said:
yep. that really explains why my Ace sounded pretty underwhelming with the stock tubes and excellent with a graded Hot set of tubes. BIG difference. It really makes me question what the hell Mesa is doing by knowingly castrating their amps like this.
Click to expand...

I'd guess that Mesa would have to throw a lot of tubes in the bin if they only sold the hot ones on.
 
I tried the JJ EL34s in my Ace but was generally unimpressed. The TungSol EL34Bs sounded a whole lot better to me. I've had them in for quite awhile now, so I'm pretty much sold on them. I'll have to put my meter on and see what it says...might be interesting to know.
 
Its less about the brand of the tube and more about the rating. E34L is supposed to have a bigger bottom end than regular El34s, something I think the Stiletto benefits from.
 
ochrisl said:
Its less about the brand of the tube and more about the rating. E34L is supposed to have a bigger bottom end than regular El34s, something I think the Stiletto benefits from.
Click to expand...

Yes, but I guess it will depend on how the mixes are in a band...
 
ochrisl said:
Its less about the brand of the tube and more about the rating. E34L is supposed to have a bigger bottom end than regular El34s, something I think the Stiletto benefits from.
Click to expand...

I have used JJ E34L tubes in Mesa, Rivera, Marshall heads. Definitely more bottom end than regular EL34s. Mesa sells tubes to make money. The fixed bias thing is advertised as a convenience to users (which it sort of is) but the disadvantage is your tone may suffer from cold biasing. The rep at NAMM 2011 told me "how can we know what you're doing with our amps if you don't use our tubes" and I'm like "how the hell do the other brands know"?

This is one of the main reasons I don't currently own a Mesa amp. I should be able to use any brand/rating tube I want with my amps...
 
rabies said:
This is one of the main reasons I don't currently own a Mesa amp. I should be able to use any brand/rating tube I want with my amps...
Click to expand...

I assume your are talking from a warranty perspective because other than that you can put in any tube you like. There are a number of shops that can even match a tube set to the Mesa requirements. Or even hotter or colder if you want all without even looking at bias kits.

Personally I don't find fixed bias to be a restriction. The fact that Mesa can offer one of the longest amp warranties in the industry is because they have a reliable product. Fixed bias in part contributes to that reliability. To me the long warranty is more peice of mind.

How many people have cooked a mesa by putting non Mesa tubes in them anyway ?
 
J.J said:
rabies said:
This is one of the main reasons I don't currently own a Mesa amp. I should be able to use any brand/rating tube I want with my amps...
Click to expand...

I assume your are talking from a warranty perspective because other than that you can put in any tube you like. There are a number of shops that can even match a tube set to the Mesa requirements. Or even hotter or colder if you want all without even looking at bias kits.

Personally I don't find fixed bias to be a restriction. The fact that Mesa can offer one of the longest amp warranties in the industry is because they have a reliable product. Fixed bias in part contributes to that reliability. To me the long warranty is more peice of mind.

How many people have cooked a mesa by putting non Mesa tubes in them anyway ?
Click to expand...

Soldano and Diezel are lifetime warranties (thus more expensive)

Mesa amps cook with mesa tubes, trust me. happened to me and mightywarlock (stiletto and 2 mesa V's)

enjoy
 
I wondered why those guys are more expensive.

Mesa's choice of tubes and tube quality is debatable. I'd bet better tubes would result in many less failures all round.
 
I can recommend the bias kit.
Sound quality improved much because without it, the tubes are stock biassed way too cold. I can put in any el34 tube brand in my ACE.

grz!
 

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