my first TUBE AMP! Valves

[zsimmen]

I am new to the tube amp. I bought my first tube amp with money I saved up cutting grass all summer a few months ago and I've fallen in love! Now I'm on the search for MY tone. I'm young and I don't know much about it. I've spent the last 7 days researching and trying to figure valves out. But I figured I'd rather join a community to get suggestions from people with experience (my dad suggested this to me). So this is what I have in mind but don't know what exactly to do.

My Amp-

V32 Palomino (St. Louis Music;US made) Crate
- Upgraded Celestion Greenback Speaker
- JJ EL84 Power Tubes
- Stock 12AX7 preamp tubes

Guitars

Hagstrom Viking Semihollow body
PRS SE Custom

Effects

Vox Tonelab LE

What I THINK I want to do:

Buy new preamp tubes (either 12AT7 OR 12AY7 OR 12AU7's I'm still confused on what those will do and how dramatically I'll be affected and what exactly will be affected) to bring the gain down (The amp is so loud that for my applications I'm typically on 1)

Make the tone warm but with a crisp clean sound. The humbuckers may make it too muddy?

What preamp valves do you suggest for what positions? V1V2V3? and why so I can learn? I am on a limited budget obviously or I'd love to just buy a bunch of tubes and go to town.. by limited I have like $100. I want to do it right and get something that is gonna be great the first time. Any help would be awesome!

attached is the amp manual

[10thTx]

Welcome to the forum. I hope your experience with tube amps is a great one!

I typically will use either a 5751 (gain factor 70) or a 12AY7 (gain factor 45) in the preamp.

The reason for that is because I think they sound more "musical" than something like a 12AT7 or 12AU7. I would tend to use 12AT7's in the phase invertor or reverb position but not in a preamp.

There is a chart on gain factors here: http://www.thetubestore.com/Resources/G ... ain-Factor

Over time, you learn how to read schematics & there is a schematic for your amp here:
http://www.el34world.com/charts/Schemat ... lomino.pdf

A reasonable starting place for modifying your amp is to change preamp tubes and replace the amp speaker (if you're not liking the speaker you have now).

with respect, 10thtx

[martin manning]

If you want to try rolling some tubes on a budget, I'd suggest getting a new JJ 12AX7, and 5751, an EH 12AX7, and an EH 12AY7. Substituting in a 5751 or 12AY7 will lower the gain of two stages (there are two triodes in each glass envelope), and you will get a cleaner tone. Different tubes of the same type will sound somewhat different, particularly in the first position, so substituting a different 12AX7 will have some effect. These new production tubes can be had for around $15 each. If the power tubes are worn that will affect the tone as well, but more importantly a power tube failure can cause significant damage to other parts.

Something you may have noticed is that this amp runs hot. The power tubes are biased hot at idle, and their cathode resistor is located directly under the mid control, which causes it to get hot to the touch. Down the road you might consider some mods to cure those issues.

[Littlewyan]

If you're after a decrease in volume then changing to a lower gain pre amp valve will hardly make any difference. The only way you could lower the volume really is by using an attenuator or installing a Master Volume, which in this amp I'm not too sure about.

Are you sure this amp cannot get the tone you are after? You will probably find that once you can crank the volume the tone will change and may be what you're looking for. Also really have a play with the EQ, you'll be amazed at what tones you can achieve by doing this. As you're on a budget and want to get it right it'd be a good idea to take the amp to a place where you can crank it up, play through it for as long as you can so you can then decide if its the right amp for you.

[zsimmen]

Awesome info so far. I suppose I meant lowering the gain so that I can have more tonal capabilities at lower volumes. Does that make sense? I'm not entirely just after lower volume, just more gain possibilities at lower volumes. I don't typically use a lot of gain.

The speaker is already upgraded to a Celestion Greenback and I think the speaker sounds great. I am able to crank the amp to reach some awesome sounds, however at those gain levels I'm going to go to jail for giving my neighbors and parents an ear bleed and concussions from bouncing their brains around in their skulls. Which led me to begin this quest. Also I've heard that a preamp change can liven up the tone as I'm looking for crisp cleans with a warm and inviting mid range tone. This just gives me all the mid range cream with not a lot of crisp highs. When I try to brighten up the tone using the treble, it souds almost cheap and tacky to me.

Do you have any suggestions as far as brands go? Additionally which positions are reverb and phase invertors? Would that be on the schematic? I am having a hard time reading that one.

[Littlewyan]

Which Amp channel are you using by the way? I'm guessing the overdrive channel? If so then just out of interest do you find you get much nicer crisp high end out of the clean channel?

[zsimmen]

So from what I gather the phase inverter would be position 3.

I use both channels littlewyan.

[Littlewyan]

Ah I edited my post too late!

Do you get better high end out of the clean channel?

[zsimmen]

I would say no. I get better high ends out of the overdrive I think.. I use clean probably twice as much as overdrive channel.

[Littlewyan]

Interesting. Looking at the schematic it should be the Clean Channel but hay ho, what you see on paper doesn't mean a lot when it comes to sound! Easiest thing to do at this point then is just try different valves, as the others explained different valves have different characteristics. Can't help you there though as I've only used 12AX7s. Guys little help?

[pops]

I like 12AY7's and use them in most all amps. Slide and harp players like them a lot as they warm up the sound. I would not use a 12AX7 personally, but that is a personal choice. A 12AU7 makes a good phase inverter so you can lower power some what, but still have a lot as it sounds like you have way more than you need. You can also take the bypass caps off the preamp tubes and have a flatter response and much less gain for each stage you remove the cap. Do one at a time an play it to see what you like. They can all be removed if you like that and seeing as you like clean that may be something you would like to try. Have fun and be careful.

[10thTx]

Given your response regarding lower gain and somewhat cleaner tone, I'd recommend a 12AY7 in the 1st preamp position.

Then you can use a 12AT7 in the LTPI position which usually is the last 12A_7 tube closest to the power tubes. However, I don't know exactly how your amp is laid out on a PCB board?

Your reverb unfortunately is solid state.

Regarding a lesser volume, the 12AY7 and 12AT7 will not decrease the volume that much. It may be possible to install a master volume?

IF you can learn how to work on amps SAFELY or have an amp tech:

Another possible option might be to remove two of the power tubes and install rebias the amp with a 130ohm/10w resistor. At around 16-18 watts (using two EL84's), you will still have plenty of loudness on hand. To be honest that is what I would personally do as well as install a master volume or a PPIMV (post phase invertor master volume) also calle a Lar-Mar PPIMV.

Another option would be to look at Dana Hall's VVR. Look up Hall Amplification. And here is a thread with LOTS of info about VVR's.

http://www.el34world.com/Forum/index.php?topic=6899.0

Research and read extensively on the internet before thinking about installing master volumes and/or VVR's and such.

With respect, 10thtx

[M Fowler]

I mostly use new tubes because I have too many amps but since this is your first or only tube amp maybe you, your dad, or friends have some new old stock (NOS) tubes that you could try. Old or NOS tubes really bring out the tone.

I frequently will use 5751, 12AY7 and 12AU7 to lower gain or to smooth out amps. 12AT7 in the phase inverter (PI) position is a good way to go.

Have fun.

Mark

[JazzGuitarGimp]

You say turning the treble up sounds cheap. So you might try this: set the treble back down to where it no longer sounds cheap, then turn the bass and mids down to brighten the sound. Use the volume to make up the difference. This also has the added advantage of lowering the gain a bit, which is one of your goals.

Also, remember that your guitar has volume and tone controls, and they do not have to always be all the way up. Play with these, especially the volume control to tame some of the excess gain. There's nothing wrong with setting the guitar's volume control to the halfway point (or even lower). And, the payoff here is that when you want to get "up on top of the band" to take a solo, you just turn your guitar volume up.

Good luck!

[zsimmen]

Good points