The time for a new axe has come.

Brotherly love in action.

 

This is actually quite an involved discussion, as it depends a lot on the type of music you like to play, the sound you are trying to achieve, where you intend to play, who you will be playing with, how much you want to spend, what features you want, etc. Do you want a nice simple, single-channel, three-control amp that is clean with the volume down and overdrives as you turn it up, or a four-channel, three modes per channel midi-controlled monster with switchable power stages and supplies, reverb, multiple effects loops? Or, as is probably the case, do you want something in between? I could give you a better recommendation with that info, but I'll try to at least give you some ideas here.

First, tube vs. solid-state. I, personally, use tube amps, as I play with others, and solid-state amps just don't work in that environment, as the midrange frequencies tend to get lost in the mix. If you're playing by yourself, this may not matter to you, and the reliability and affordability of a solid-state amp may be just the ticket. Tube amps sound better to me, but this is subjective.

Second, speakers. The speaker cabinet will have the single largest impact on your sound of any component in the amp. You seem to want a half-stack, which is a good choice, as there are a lot of options out there. Speakers manufactured by different companies will sound wildly different, and the wood the cabinet is made of will influence the sound a lot -- pine cabinets have a nice, warm, woody sound, birch plywood has a sharper, more focused sound, particle board sounds muddy. What size speakers do you want? 12-inch speakers are the classic choice, but 10-inch speakers are often more focused in the midrange frequencies, which is where the guitar lives.

Next, how much output power do you need? The most important thing to bear in mind is the relationship between output power and apparent volume, which is subject to an inverse-square law, meaning that the volume doubles as the power squares. So, if you want an amp twice as loud as your friend's 50-watt amp, you need a 2,500-watt amp. Now, you don't want to buy an amp with the minimum power that you need, as you would need to run it wide-open all the time, so it's best to buy one with quite a bit more, so that you can run it at 30% of maximum volume or so. You probably don't need nearly as much power as you think, though (an aside, this works for computer power supplies too) -- as an example, if you're playing at bedroom volume, your amp is probably putting out about somewhat less than half a watt. At the other end of the spectrum, the guitarist's amp at a big stadium show is probably putting out 15-20 watts. Here are some rough numbers as far as the amount you might want for various applications:

• Playing at home by yourself: 5 watts.
• Playing with a group/band practice/small club performances: 15-20 watts.
• Medium size venue: 30 watts.
• Large venue/outdoor performance: 40-50 watts.

(These numbers are for tube amps -- multiply by 3X or 4X for solid-state, as tube amps exceed their rated output power when driven into distortion.)

Anything over 50 watts doesn't gain you much in terms of volume, but can be useful in some situations. For example, a 100-watt amp can give you pristine clean sounds at high volumes, which is useful for, say, country/rockabilly guitar.

Last, how long do you expect to use your amp? A quality amp will last decades if properly maintained. Of course, almost any amp made today will last for five or ten years if it isn't banged around too much, so if you're only planning on using it that long, you don't really have to worry about this part.

Now, what constitutes quality construction is an area in which the industry is rife with ignorance. Many will insist that the most reliable construction technique is to hand-solder all of the amp's components to terminal strips or eyelet boards, the way it was done before printed circuit boards were invented. This is time-intensive, error-prone, and expensive, and amps built like this don't tend to have a lot of consistency from one to the next. There tends to also be a lot of inductive coupling between circuits, which does alter the final sound. In my personal opinion, this technique is fine for classic reissue amps which are designed to achieve a classic 50's or 60's sound, as it's part of the sound, but that printed circuit boards are in general far superior, as they are much more reliable and consistent when done correctly. There are two areas in which there is an exception to this, though -- durability and ease of maintenance (every amp will need maintenance over a long enough timeline -- even if nothing ever goes wrong, the electrolytic capacitors in every amp dry out and need replacing after ten to twenty years, carbon-composition and carbon-film resistors drift in value, tube sockets need to be retensioned, etc.). In the area of durability, one can't mount switches, jacks, potentiometers, and tube sockets directly to a terminal strip the way they can be mounted on a circuit board, so components that stick out of the amp chassis are physically isolated from the internal components. So, if you trip on your patch cable and damage the jack, it can generally be easily replaced for a few dollars if it's attached to a terminal strip by a few inches of wire, where if it is mounted directly to a circuit board, the board will likely break, making the amp all but unrepairable (this happened to my brother's amp -- I got it working again, but it isn't the same). And, when it comes time to replace your dried-out electrolytics (as an aside, don't attempt this yourself unless you know what you're doing -- most amps contain capacitors that carry a lethal charge even when there's no power applied to the amp, actually, don't even open the chassis unless you know what you're doing), it can be a lot easier to unsolder the old ones from a terminal strip rather than a circuit board. Now, all that said, it's perfectly possible (and frequently done) to build a circuit board with none of these problems. A good, double-layered board with flying leads to external components is as durable and easy to maintain as anything. The problem is, it's cheaper to do it badly, so a lot of cheaper amps have poorly designed circuit boards, like:



Notice the jack and control pots mounted directly to the board. By way of comparison, here's a very well-designed and built circuit board in another amp:



And, here's an example of pre-printed-circuit-board point-to-point construction on a terminal strip or turret board, to give you an idea of what I'm referring to:



This got a little long, and probably a little thick, so let me know if you have any questions, and I hope it helps!

 

Avenged Sevenfold and Metallica use Mesa Triple Rectifiers currently, though Metallica has used various Mesa Mark series amps in the past, and a Rat distortion stompbox into a Marshall Super Lead on their really early stuff. Megadeth, Iron Maiden, and Slayer use various Marshalls, as near as I can tell.

Now, both Mesa and Marshall amps are (like most amps) based in large part on old Fender designs, which were themselves based on sample circuits from old RCA tube manuals. The chief difference is in the power stages -- Mesa amps are designed around Sylvania-type 6L6 tubes, while Marshalls are designed around the EL34 valves commonly available in Britain. The 6L6 has a sound that emphasizes the bass and treble frequencies, where the EL34 tends to be hotter in the upper mids. Both companies use Celestion speakers in their cabinets, though Mesa builds theirs somewhat larger, which emphasizes the bass frequencies. Both companies construct their tube amps very well (though Mesa's build quality is a little better, in my opinion) so I wouldn't worry about quality here.

If I had to pick one amp out of the offerings of both companies, I think I'd pick one of the Mesa Rectifier series (I hear great things about the Rect-O-Verb), as they have the ability to use either 6L6 or EL34 tubes in the power stage (and an extra set of power tubes isn't particularly expensive), so you can get the massive scooped-midrange metal sound and something very close to the Marshall sound as well. If your guitar doesn't have active electronics (I couldn't tell based on the pics at the start of the thread) you may want to get a cheap overdrive stompbox with one of these amps to tighten up the sound a bit for metal playing (Ibanez Tube Screamers are great, but a Roland/Boss Super Overdrive or Digitech Bad Monkey will get you there as well).

A few words on the Rectifier series: All tube amps have a rectifier -- it's just an AC -> DC converter, tubes run off of high-voltage DC, and the wall provides AC, so it's necessary. Until the early to mid-1960's, amps used diode tubes as rectifiers, because solid-state diodes that fit the application weren't yet available. Tube rectifiers are much less efficient than solid-state, which when used in the amp's power supply, results in a mellow, compressed, tone, as the power supply takes a few fractions of a second to provide amplification power when you pick a guitar string. Mesa provides both, in a switchable configuration, so that one can get mellow vintage tones and tight modern tones without needing to buy two amps. If you're only interested in modern metal tones, I'd recommend sticking with the Single Rectifier amps, unless you want the extra channel or higher wattage available on the Duals or Triples.

All that said, this is just a recommendation of something to try. Find a dealer in your area and try out a few different amps. Bring your guitar along, so you can get a feel for how the amps react to it (I've never met a dealer who minds if you do this). While you're at it, try out some other Mesa amps, and some Marshalls (you might like a Marshall JCM 2000). Guitar Center might be a good place to start -- many of them carry both brands. I own a Mesa F-50 amp, which is a derivative of the Mark series amps frequently used by Metallica. I don't know if Northern NY is convenient for you, but if it is, you're welcome to come by and put the amp through its paces for an afternoon if you like.