Sound — 9
I'm using an Ibanez RG4 equipped with the DiMarzio Liquifire and CrunchLab and play mostly progressive/classical/metal/whatever you want to call it. I'm also using some Boss, and Visual Sound effects as well as an Ernie Ball VP. I wouldn't go as far as the other reviewers have in saying that this amp can give you some brutal distortion. Even though the distortion that I've gotten out of it is pretty badass it doesn't come close to the rectifier series, but it's not supposed to. From the lead channel I can get a very tight, defined rhythm sound that takes you right to the edge of good metal tone using a combination of the graphic EQ and various other features. A little bit more distortion and it would be perfect for metal but you can use a pedal and fix that immediately if the amp isn't heavy enough for you. It'll cover about everything you want though. The lead tone that I can get is absolutely phenomenal. It's retarded good! With my bridge pickup I can produce some searing solos and the Mark IV definitely makes my Liquifire shine. The tone is so smooth and beautiful. The only issue is that it doesn't seem to produce the amount of sustain that I would like. Legato lines are a little difficult, but, again, I think a distortion or boost pedal would solve this problem. The harmonics leave a lot to be desired. Both pinch harmonics and natural harmonics are difficult to produce with any pronounced feel at all. They just seem to get lost and dwindle or never jump out at all. The clean channel is great. You can crank the settings to get some crunch from rhythm1 but that's the beauty of rhythm2 channel. Once again, it's easy to make the bass and mids produce that "flub" sound so roll off of them until you find the definition you want (Petrucci's terminology). But once you get the EQ dialed in the results are wonderful. Overall the sound of this amp is AMAZING once you put in the time tweaking the settings.
Overall Impression — 10
For my style of music I knew that I had to have a Mesa. The lead channel alone is worth the price of this amp. I've been playing for 6+ years and have owned many solid state amps. I must admit that this is my first tube amp but I believe it was a great choice. If it were stolen I would cry because I don't have the money to buy another:( I love the cleans and lead channel on the amp. I wish it had more sustain and distortion but a cheap pedal can fix that in a heartbeat. I did play around on other tube amps before deciding on this one. None of them had that signature Mesa tone. The RECORD OUT feature is wonderful and sounds great. The power options are great. The reverb is great. This amp is just overall great. My next amp purchase will be the Mesa Mark V or possibly the Dual Rectifier. Who knows. It'll be awhile though:P in the meantime I'll enjoy the f--k out of my Mark IV.
Reliability & Durability — 9
My Mark IV I bought used. Already I've noticed that every now and then the volume and gain crackle and go out. I'm suspecting that a tube needs replacing. I'm not sure when the last time the previous owner changed the tubes was. Also, there's a problem with the master volume control on the Rhythm1 channel. Around five the volume seems to jump up to max with some wiggling of the knob. But as you continue to turn it up it drops back to the correct value such as 7 and 8 and on up to max at 10. None of these problems are major and they can be easily fixed with some maintenance and work from a shop. I'll change out the tubes sometime soon. Keep in mind that this amp is like 20 YEARS OLD! Tip: Never gig a tube amp without a backup :P
Features — 9
Straight from Mesa's site: 85 Watts, Simul-Class Power / 4x6L6, 5x12AX7, Fixed Bias for Consistent, Maintenance Free Performance, 3 Channels w/Independent Gain & Master Controls (Rhythm I, Rhythm II & Lead), Independent Treble & Presence Controls for Rhythm I & II (Bass & Mid combined), Fully Independent EQ for Lead Channel (Bass, Mid, Treble & Presence), Multi-Stage Cascading Gain Lead Channel (Lead Gain + Lead Drive), Lead Voicing Switch (Mid Gain/Harmonics), Pull Fat (Rhythm II & Lead Channel), Pull Bright (Rhythm I & Lead), Pull Shift Presence Controls (Rhythm II & Lead), Assignable 5 Band Graphic EQ, Assignable FX Loop, Slave Out w/Level Control, Spring Reverb, Output Level Control (over all channels), Full Power/Tweed Variac Switch, Simul-Class/Class A Switch, Pentode/Triode Switch, Record Out w/Level Control, Silent Record Mute Switch (Pull Output Level), Fan Cooled, External, Switching Input, 6 Button Footswitch (Rhythm I, Rhythm II, Lead, Lead+EQ, EQ (Graphic) & FX Loop), Slip Cover. Okay, onward to reviewing. My Mark IV is the compact combo version and was made in 1991! Old... I know. There are so many great features on this amp one could easily get lost tone tweaking for days, but there are some complaints that I have regarding the EQ. Why on earth is there such a large range? The mid and bass controls for the lead channel have way too lare of a sweep. Anything past 5 sounds horrible on either. You lose any sign of definition and it just ends up a sloppy mess. Also, the bass and mid controls for Rhythm 1&2 are combined which presents an obstacle: finding a setting that sounds good for both your clean and crunch channels. I'm glad the treble and presence controls are separate though. The RECORD OUT feature is wonderful. To record stereo you have to use some other effects. I am moving away to college soon and it helps to be able to use my amp without getting thrown out of an apartment. On another note, the pull/push knobs bother me. I haven't had any problems with them so far, but I'm just scared that I will break one off because they stick out pretty far. As far as features go there's not much more you could ask for. The Mark V did solve the problems I mentioned btw (pull push knobs and combined bass/mid on Ch.1&2 were switched to toggle switches and separate EQ for all channels).