Question about valves

Lux84

New member
I am buying some preamp valves and i don't know what is the difference about balanced and non balanced valves.. which ones should i get for V1,V2 and V3 positions? i noticed the balanced valves are more expensive, is there any particular reason for that?
 
Re: Question about valves

No need for balancing.
Some people say that it is good to have the phase inverter balanced, but seeing as the components in the amp are often 5% out, the gain is moot.
Ive been playing tube amps since the 80s and never bought a balanced tube.

The reason for people wanting balanced tubes might be something to do with the fact that generally you want "matched pairs" for your power tubes (ie. both your power tubes are rated the same). Preamp tubes like a 12ax7 are actually a dual amplifier, so i guess some people think that having both halves matched might make a difference. It really doesnt, especially as in most preamp tubes, both halves of the tube are doing different jobs rather than working in a push/pull configuration like a pair of power tubes.

Don't lose any sleep over it. If you really want to spend the extra cash, try experimenting with different brands.
 
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Re: Question about valves

Thanks, man ! i didn't know where to ask so i putted the question here. i'll be putting some Tung Sols and JJ preamp tubes in my Randall Diavlo RD 45.
 
Re: Question about valves

Balanced valves ("balanced triodes", etc) only really matter in the audiophile world.
 
Re: Question about valves

So, you recommend unbalanced valves?

There is no such thing (there is such a thing as "matched", however - but that is in relation to a pair/quad powertubes' current draw).

What they mean is "unbalanced triodes" and specifically preamp tubes like the 12AX7.

The 12AX7 (and similar) are actually 2 triodes in one bottle.

One side may not be 100% equal to the other side.

Pointless paying extra $$$ for "balanced triodes" in a tube guitar amp.

In the tube stereo/power amp/audiophile world, that's a whole different ball of wax. This is where the real corquesniffing happens.
 
Re: Question about valves

If you are replacing the power tubes, replace the phase inverter; I would use a balanced 12AX7 in this socket. Don't worry about using balanced preamp tubes in the other sockets.

Bill
 
Re: Question about valves

So i ordered unbalanced tubes, two 12AX7's, i will try them in V1 and V2 positions. i ordered one Tung Sol 12AX7 for V1 and one JJ ECC83S for V2. for now i am just gonna try them in those two positions and leave V3 and PI with stock Rubys. the amp got 4 preamp 12AX7 Chinese Rubys, and 2 6L6 Chinese Rubys. i have a feel that the lead channel of the amp should sound louder and that is the main cause i am trying new tubes.. V3 is for cleans, but cleans sounds loud enough for me so i am gonna leave the stock tube here. V1 and V2 are for lead channel of the amp so i am gonna replace the tubes here, to see if the lead channel will become louder ;)
 
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Re: Question about valves

What amp is that? I doubt very highly that any amp has both V1 and V2 solely dedicated to the lead channel. Does your amp not have a tone stack? cathode follower? Changing the tubes wont really effect the volume of the lead channel.

Does the amp not have separate channel masters?
 
Re: Question about valves

For a smooth sounding and quiet tube, try a 5751. For PI you can't beat the performance of a 12 AT7.
 
Re: Question about valves

What do you mean by that, Edgecrusher ?

From the informations i got on the rig talk forum the V1 and V2 are for OD, and V3 is for cleans.. the thread was going on about the Randall Diavlo RD 45 amp. that's the amp i got. the main problem is, that the clean channel sounds louder than lead channel to me. so i wanted to replace the V1 and V2 tubes. i already pulled the V3 tube out, and clean channel than shutted off, so the V3 is definately for the clean channel.
 
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Re: Question about valves

You wont get more volume out of the gain channel by swapping tubes. You might get more clipping but not more actual volume. In fact the very nature of clipping is that when clipping it wont go any louder. To make it so you can adjust the volume of a gain channel must be dont elsewhere in the amp not with the tubes.
 
Re: Question about valves

I thought the drop of the volume might be the issue with a weak tube. i don't really know if the amp is working properly so i might be better off drive the amp to technican just to check things out. the thing is.. my other amp JCM 800 2204 is much louder than Diavlo at the same master volume levels. i know it's a different amp but anyway.. i think i want to check the things out to be sure i am having a good working amps in band situations.
 
Re: Question about valves

Yeah you cant compare the output just by the numbers on the knob alone. Many things at work will make them different. IF there is actually an issue with a 12ax7 then maybe a new one will make your OD channel louder. But 12 ax7's dont die like power tubes do.
 
Re: Question about valves

Tried Tung Sol in V1 and JJ 83 in V2. i am not impressed. sound is somehow fuller but that's not what i want. i will get back the chinese Ruby in V2. maybe try another Tung Sol in V2 later. at the first feel i cannot say, i probably must crank the amp a few more times to hear some difference.
 
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