My Crate V18-212

[bombtek]

I know it is not the most desirable amplifier to be had, but I kinda like it. It was dirt cheap for a tube amp and it is really really loud.

Of course there's gonna be some bad things about a product like this it is waaaay too dark when overdriven. Pedals sound absolutely fine through it, but I'd like to hear what this thing should sound like. there has got to be something inheritently wrong with how its wired for it to sound so damn muddy. I've been looking online for a long while now at mods that folks have been doing to their V18's and from what I gather according to the modders, this amp is a jewel once sorted out correctly.

There is a Soldano SLO mod that a lot of folks have been doing to theirs that apparently really opens up the headroom when used clean, and takes out the muddiness of the overdrive. It does not by any stretch of the imagination turn a $200 amplifier into a $3000+ amplifier, but the mod is modeled after the SLO circuit and is supposed to REALLY open this amp up.

What I am really looking for is when playing clean for the tubes to not break up so early. This thing needs more headroom for cleans. It seems that the mods might do this as well as brighten up the overdrive. I'm not really too concerned about the overdrive sound though as I attain any distortion I need through any one or combination of a shitload of pedals .

Do you folks that have experience in modding amps think it would be worth it to send mine out to someone, or do you think that someone like me with little to no experience with amplifier guts would be able to do this?

For my job (my username ), I have been trained to analyze, plan and attack complex electrical circuits to disarm IEDs, armed explosive ordnance, armed nuclear warheads and such things many of whichhave multitudes of very complex electronics, and I've built undefeatable training IEDs with hordes of complex circuits that were a damn nightmare for those trying to defeat them. But I've never tried to conquer a tube amp using someone elses schematics or diagrams. In short, I know more than enough to take it apart, but putting it back together CLEANLY is where I'm afraid that I might fail and screw up my one amplifier.

[atdguitars]

My first suggestion is to switch the 12ax7's to a 12AT or 12AU. They are much cleaner with less distortion. It's a cheap swap. Replace V1A with a 12AU7, V1B, 12 AT7. Leave the third 12AX7 in place. This will clean up your signal tremendously for a clearer cleaner output at higher volumes. If your budget allows replace the factory EL84's with a higher quality matched pair of power tubes. I use JJ's in the shop due to reliability and value.
The quality of the speakers could be suspect as well and would be my next step in getting better tone from the amp.

[bombtek]

My first suggestion is to switch the 12ax7's to a 12AT or 12AU. They are much cleaner with less distortion. It's a cheap swap. Replace V1A with a 12AU7, V1B, 12 AT7. Leave the third 12AX7 in place. This will clean up your signal tremendously for a clearer cleaner output at higher volumes. If your budget allows replace the factory EL84's with a higher quality matched pair of power tubes. I use JJ's in the shop due to reliability and value.
The quality of the speakers could be suspect as well and would be my next step in getting better tone from the amp.

Thanks for the tips, I'll look around and see where and how much for these tubes.

If you have heard of the SLO mod for this amp, do you think it is worth the effort and can a know-nothing like me do these types of mods.

[atdguitars]

JJ's aren't expensive. They normally retail for about $14.00 each.
For the power tubes a matched set should be no more than $40.00
The mods on a PC board can be tricky . It's hard to trace some components. If you can read a schematic, which I am sure you can with your training, and handle a soldering iron you can do these mods.

[Cygnus X1]

+1 to all of the above.
You won't get as much volume by toning down the mu on the preamp tubes-you'll give up some gain. But you will get more range of clean tone.

That amp isn't really designed to get much clean headroom but some small changes can make a difference.

From the description, that "holy grail" blues amp is the Marshall 18 Watt. I built a Matchless Spitfire based roughly on the same circuit.
The EL84's are VERY touchy so getting the right ones might just do everything you want without changing the preamp tubes.
And make sure you have a good quality PI (driver 12AT or AX7) tube in there.

I've seen and heard good comments on the JJ's.
I got crazy-lucky and chanced on some Holland Amperex NOS EL84's for the Spitfire. They sound much better than the Sovtek's I had in it originally. More headroom, chimey clean.

And if you are interested in using your skills to start modding/building, I recommend building a 5E3 Tweed Deluxe for yourself. Great way to learn basic amp circuitry and the 5E3 is an awesome sounding blues/rock amp.
I would stay away from the printed circuit boards to start, as atd mentioned. They are PITA to deal with and often no turning back if something goes wrong.
Turrets/eyelets/point to point are far more forgiving, and sound great if laid out correctly.

[MonteChristo]

I have the 1x12 V18. A speaker change will get rid of the mud and a lot of darkness. It is 100% doped. A change of preamp tubes will change it's voice as well. Just a higher grade 12ax7 will make a big difference. I have a 12au7 but haven't tried it yet. Sounds like a step forward.

[bombtek]

I have the 1x12 V18. A speaker change will get rid of the mud and a lot of darkness. It is 100% doped. A change of preamp tubes will change it's voice as well. Just a higher grade 12ax7 will make a big difference. I have a 12au7 but haven't tried it yet. Sounds like a step forward.

I think I am going to "undope" the speakers. I've read some pretty convincing reports of folks that used acetone (readily available to me at work), brushing it on with an acid brush, wiping them down with a towel and letting them dry for 24-48hrs. It supposedly makes them a pretty damn good speaker after the doping is removed.