Mixing pre-amp valve brands

[jordan]

Bit of an odd question this, but bare with me....

My Rivera R55 has 5 x 12AX7 preamp valves in. I got it second hand a few months back, and I think it would benefit from some new valves. At the moment there are 4 different brands of pre-amp valves in the 5 positions. Now, was the owner before me most likely to be a) extremely knowledgable and and had picked the best brand of valve for each position, or b) a cheapskate who threw whatver he could find in there? :)

So the question boils down to: is it common practise to put 5 of the same brand of valve in (I'm veering towards Electro-Harmonix 12AX7-EH), or shop around looking for the best brand of valve for each position. I've seen adverts on certain Mesa valves stating things like "the ideal 12AX7 for the main driver position" etc etc, and I wondered if this was just hype?

Any input appreciated....

Cheers,
Jordan.

[Twinfan]

I'd go with all the same, but I'm not Eric Johnson when it comes to tone.

I believe the Harma Cryogenic treated tubes by Watford Valves are the puppies to have at the moment.

[indysmith]

I believe the Harma Cryogenic treated tubes by Watford Valves are the puppies to have at the moment.

Ohhh yeah they're definately in this season

[bubchronic]

Hi
Valves are meant to be installed as matched sets ( according to Marshall ) so either the previous owner measured resistance etc and matched them himself, or he's a cheapskate. I would say it's best to at least use all of the same brand.

bub

[indysmith]

Hi
Valves are meant to be installed as matched sets ( according to Marshall ) so either the previous owner measured resistance etc and matched them himself, or he's a cheapskate. I would say it's best to at least use all of the same brand.

bub

I think this only applies for power valves...?

[TwilightOdyssey]

If you're not absolutely certain about what you're doing, keep them all the same.

[steve]

Hi
Valves are meant to be installed as matched sets ( according to Marshall ) so either the previous owner measured resistance etc and matched them himself, or he's a cheapskate. I would say it's best to at least use all of the same brand.

bub

That applys to power amp valves. I really like the Harma 12ax7 preamp valves,really warm and detailed.

[Searcher]

but bare with me....

Nuh-uh.  I've got in trouble for that before.

[HTH AMPS]

There is no reason to have all the preamp valves the same, then again there's no reason to randomly put loads of different makes in either.

The preamp valve that has the biggest impact on the basic tone you hear is the first preamp stage (most likely labelled as V1 in your manual - it will also be the preamp valve closest to the amp's input in most cases)

Get yourself a few different brands of ECC83/12AX7 and try them in the V1 position - you should hear a clear difference.  Once you hear the tonal slants each valve types have you can experiment with some of the other positions.

 :twisted:

[OD-Black_Fire]

Is it possible to "darken" your tone, or "tighten" it with a change of preamp tubes? I like my current amp, nice and evil, but it sounds more like a hotrodded Marshall, sort of like Engls but isn't as tight. Perhaps, with a change of tubes, I can make it a bit darker (more like a Duel Rectifier) and tighter?


I have not cranked my amp yet (B-52 AT-212 combo) and it's sorta set up like the Rectifiers, It could actually be darker and I'm just not cranking it enough XD.  Need a hotplate.

[HTH AMPS]

yes, it's possible to change the sound of your amp quite a bit depending on the preamp valves used and the circuit topology.  Try an ECC81 in the PI position, slightly less gain but also more bass and tighter tone - I like this in my homebrew high-gain amp.

 :twisted:

[Crazy Gra]

OD,

I heard those B52's are loud and pretty damn decent too. I think you're onto a good thing with the hotplate.

Anyhow, I have a BRIGHT Fender DRRI and I put some Mullard NOS preamp tubes in. Normally I wouldn't bother with a tube that costs mega $ but I got these for 15 lousy aussie $ each. They certainly smoothed the distortion and took some icepick tone away. I put JJ's (6V6 in my amp) in the power side but didn't notice much difference from the EH version. I'm gunna try EH's in the preamp side next (to avoid using the priceless Mullards).  

Position one on the preamp side seems to make the biggest difference as far as preamp tubes go.

So yes changing tubes will help change the tone (but I think it's generally accepted) not as much as changing the speakers............... oops that's a whole new can of worms.......

Have fun!

[Underground_Player]

I'm gunna try EH's in the preamp side next

I'd just like to say that I've tried a few different pre-amp valves, and EH 12AX7s were the only ones that particularly stood out for being bad! They were distinctly brittle and fizzy compared to the other brands. Of course I could have happened to get a bad couple and my Seymour Duncan's a very different amp to your Fender, and I know there's at least one person on this board somewhere that really likes them....could be horses for courses, but if I was you I'd look at other brands first.

not as much as changing the speakers

Totally agreed there  :)  Speaker changing is underrated guys!

[OD-Black_Fire]

My amp is a combo. It can't be easy to change the cab then. It's half open in the back, I could close it up totaly but I would loose some airflow. It would make it tighter.

I heard the material of the wood makes a difference too. I remember reading a thread about some cab model that had some rubbery stuff sandwiched between wood and it was known to have a very tight warm sound.


I downloaded a clip of a Ibanez Tube Screamer boosting a distortion channel and it tightened it up also.

[Crazy Gra]

I'm gunna try EH's in the preamp side next

I'd just like to say that I've tried a few different pre-amp valves, and EH 12AX7s were the only ones that particularly stood out for being bad! They were distinctly brittle and fizzy compared to the other brands.

Tried the EH12ax7 on the weekend and let's just say I pulled them out real quick. I put JJ' (ecc83s) in instead and they were a massive improvement over either Sovteks or  EH.

Eh12ax7 are a total waste of money for my Fender...........but I had to try ........ I got 'em cheap and now I know why!

With the B-52 it's not going to cost you much to try closing the back so I'd give it a go!