MXR M66 Classic Overdrive

- Output knob (aka volume)
- Tone knob
- Distortion knob
- Internal voicing switch
- LED
- External 9 volt power connection
- Internal 9 volt battery connection


UTILIZATION

It really does not get much simple than this. The Output knob is your volume, the distortion knob controls the amount of gain, and the tone knob control the equalization of the signal. Turning it up gets brighter tones, turning it down gets you darker tones.

SOUND QUALITY

This pedal basically sounds like juiced up Tube Screamer. I’ve found that with some amps it sounds phenomenal and on other amps it sounded dismal. All of the amps I have tried it on were tube amps. I'm not sure what causes the huge disparity in tonal quality other than the preamp design.

It has a fair amount of gain on tap. When mated with an amp the pedal likes the EQ knob is quite useful. When mated with an amp it doesn't like, it goes from bad to worse. Similar problems occur with the signal volume.

This is basically the same review as the Classic Overdrive. Why? Because, to me, they sound almost identical. The Classic Overdrive has a slightly more midrangy sound where as the Classic Distortion is slighty more scooped, has a little bit more bass, and is a little more compressed. It has a little bit more gain on tap, but nowhere near what someone would consider to be a lot of gain. There is a reason they call it a "Classic" distortion pedal.


OVERALL OPINION

MXR sold these pedals on a limited basis through Guitar Center only. Then Guitar Center ending up blowing them out at $30. It's a steal for $30 and worth the gamble to see if it will create magic with your amp. The prices on the aftermarket are starting to creep up. If you can find one cheap ($50 or under), it's probably worth checking out.

- Output knob (aka volume)
- Tone knob
- Gain knob
- Internal voicing switch
- LED
- External 9 volt power connection
- Internal 9 volt battery connection

UTILIZATION

It really does not get much simple than this. The Output knob is your volume, the gain knob controls the amount of gain, and the tone knob control the equalization of the signal. Turning it up gets brighter tones, turning it down gets you darker tones.

SOUND QUALITY

This pedal basically sounds like juiced up Tube Screamer. I have found that with some amps it sounds phenomenal and on other amps it sounded dismal. All of the amps I have tried it on were tube amps. I'm not sure what causes the huge disparity in tonal quality other than the preamp design.

It has a fair amount of gain on tap. When mated with an amp the pedal likes the EQ knob is quite useful. When mated with an amp it does not like, it goes from bad to worse. Similar problems occur with the signal volume.

There is a switch inside the pedal that changes the overall voicing of the pedal. Based on the clips I've heard, it's not a huge change but it requires you to take the entire thing apart (unscrew the knobs and pots) which I haven't gotten around to doing yet. A lot of people have been modding them with an external switch.


OVERALL OPINION

MXR sold these pedals on a limited basis through Guitar Center only. Then Guitar Center ending up blowing them out at $30. It's a steal for $30 and worth the gamble to see if it will create magic with your amp. The prices on the aftermarket are starting to creep up to around $100 and at that price; I don't think it’s that good of a deal. There are things around that price that will sound much better and probably do so more consistently.

The MXR Classic Overdrive is actually two pedals in one. There is an internal switch that when pushed one way the circuit is the exact same as the MXR GT-OD, and when pushed the other way it the circuit is the exact same as the MXR Wylde OD. Nobody is really sure why MXR made this pedal, but it seems to be a Guitarcenter exclusive model. I got it used for $20, and the retail price is normally $40. Still, a silly good deal for what it is.

The Classic Overdrive has three controls. "Output" "Tone" and "Gain", plus the switch on the inside that MXR doesn't tell you about. It uses hardwire bypass, which is NOT true-bypass, but it isn't bad, no tone-suckage as far as I can hear. Standard LED indicators, and it can be powered by either a 9 Volt battery or a power-supply.

UTILIZATION

Tweaking the three knobs to find your tone isn't hard at all. It has enough volume on tap as well so that you can use it as a boost if you wanted as well. The internal switch to switch it between the GT-OD and the Wylde-OD is mounted on the side of the circuit board that faces away from you when you open the back of the pedal up. I un-soldered the switch and moved it around to the front so I could change between the two without having to pull the PCB out. When I got it it didn't come with a manual, but hey, with only three knobs it doesn't take a rocket scientist to figure it out!

SOUND QUALITY

I run a Peavey Ultra all tube 60 watt amp pushing a 5150 Straight cab with V30's and G12T-75's, and my main Genre is thrash metal with some drop-tuned stuff thrown in. I can't say I use this pedal very much in my normal playing, but when I play for church it comes in handy.

I set the Peavey's three channels for Clean, Light DistRhythm, and Heavy DistLead. I then set the MXR up as a medium gain overdrive, lighter than the Rhythm channel, but still enough gain to provide a little crunch. Does the MXR sound as good as one of my amp's OD channels? Well, it doesn't sound as natural, but it still sounds good, and fits very well for what we play.

Oh yeah, the tonal difference between the GT-OD and Wylde OD settings is that the Wylde OD has more bass, and that's about it. They are very similar sounding, but the Wylde setting tends to work a little better for boosting an amp IMO.

OVERALL OPINION

Overall, this is a great pedal. It's built well and sounds good, and it is priced crazy cheap. Would I buy it again? Heck yeah. Even paying the retail price of $40 it is still a crazy good deal. I like that I can use it to bridge the gap between my clean and first OD channel, and that I have two different settings depending on how much bass I want. I would prefer that it had true-bypass, but the bypass on it now isn't bad by any means, so that's not a huge deal. I highly recommend that you try out the MXR Classic OD, especially if you are looking at getting either the MXR GT-OD or Wylde OD.

This pedal is MXR's budget version of their popular Custom Shop GT-OD overdrive pedal, and is made overseas and rehoused in a slightly different color green box with a little "tramp stamp" design on the sides of the footswitch. It was sold as a limited run exclusively at Guitar Center stores, along with the M-86 Classic Distortion which I reviewed earlier.

It sounds very similar to the GT-OD, but the pedal itself weighs much less and is made with lower grade components. It still feels solid and well built. Actually, it feels too solid! Well, the switch does anyway. I literally have to force most of my weight into the switch for it to press down and click, and I weigh between 180 and 190 lbs! I contacted MXR about this and they said they would swap out the footswitch if it was a big deal to me. I haven't done it yet, but that goes to show how great MXR customer service is! Most companies wouldn't even bother with such a cheap pedal, and especially not on their dime!

UTILIZATION

The Classic OD is very easy to operate. Three familiar control knobs make it simple. Twist and play!

SOUND QUALITY

The tone of the Classic Overdrive is definitely based on the Tubescreamer design. It sounds like a variation of the 808 platform to me, as it's much warmer, with more "bark" than the TS9s (which I really do not care for) It has a slightly chewy character to the gain.

In fact, I actually prefer this cheap pedal to the Ibanez TS9. It feels better to play and the tone is warmer and not flat or thin like the TS9.

There is a pretty good amount of gain on tap for a TS type pedal, almost as much as the Classic Distortion as a matter of fact.
As a boost, this unit fares pretty well, but no matter the gain setting, it always injects its "dirty" low end into the amp's sound and response. I find most MXR pedals to have this dirty, messy quality, although in this pedal it's minimal.

I prefer this pedal as a stand-alone overdrive box through a very clean amp, rather than boosting a dirty amp. It easily holds its own and rivals other overdrives and TS clones costing two to three times as much!

My only complaint is that the tone knob isn't fully usable throughout its entire range. In fact I really only find the sound usable with the tone control around Noon. Less than that, it becomes muddy and muffled, and set higher than noon, it becomes a bit unnatural and overly bright.

That's no big deal though, because it does sound great in at least one setting, and if all I can get from a $30 pedal is one great overdrive sound, that's still a win as far as I'm concerned!


OVERALL OPINION

At $30 this pedal is a steal. At twice that I would still buy it. I did get rid of my Ibanez TS9 after buying this one, so that should tell you something. Go for it, and buy the Classic Distortion too while you're at it!