MichaelW
Well-known member
- Build Rating
I was a little ambivalent about building this pedal after my experience with building the ROG "Umble" which I find rather underwhelming and don't think sounds anything like a Dumble.
This is their take on an MIAB or more accurately a PIAB, or even more accurate an SLPIAB hahaha.
Boy, was I wrong about being ambivalent....this might be the best Plexi in a box pedal I've ever heard!
Just about every MIAB pedal I've built so far, while sounding good, have a couple things in common, too much bass and too much gain.
My favorite so far has been the Golden Falk, as you can dial a lot of that bass out by adjusting the Treble Gain and Bass Gain channel ratio. But it's still got way too much gain to be considered a Plexi in a box. (Even though its got a JTM/SLP/JCM toggle.
The ROG Thor is a true Plexi in a box. It's not a super high gain pedal but does an amazing job capturing a cranked Plexi. It's voiced very well that you really don't miss the lack of dedicated tone controls. There are two toggles, a "high cap" toggle that simulates the high cap on a Plexi that kicks in as you turn the treble control down on the amp, and it's also got a Bass toggle that simulates running through a 4x12 cab.
If you're a Marshall pedal fan, this a highly recommended build. Here's the write up on the design notes for this circuit from the ROG dudes.
I biased Q1 and Q2 according to this article (6.4v and 4.5v respectively) and it sounds perfect!
In my demo I did some comparisons with an actual cranked plexi amp (well not a true plexi but a Marshall Origin 20) and honestly, I'm a bit torn between whether pedal or the amp sounds more like a real SLP.
About the amp:
I picked this up recently but didn't post about it because I wasn't sure if I was going to keep it. Still not sure actually heh. But I got it for a steal and should be able to flip it pretty easy and be whole. The Origin series of amps seem to be pretty polarizing in the Marshall world. Seems like folks either love it or hate it.
It's part of Marshall's budget line of "vintage style" amps built overseas (in Vietnam I think). Aside from the usual snobbery for anything not hand wired in the UK, it's a unique circuit and take on getting the Plexi sound, which is what it's designed to do. It has some modern amenities like a master volume and an efx loop.
One of the more common complaints is that it's a bit bright and harsh. If you try to approach it like a real plexi it does indeed sound a bit harsh. But there are some easy configuration hacks to compensate for that. I've found that the master vol is kinda useless in the traditional sense. So the way I run it, is to pretty much dime the master and control the level via the preamp gain control. Also, in lieu of a Treble Gain and Bass Gain, the amp is internally jumpered and uses a TILT control that allows you to blend the two channels to taste. I find this extremely intuitive and love it. The last little hack is to not use the treble control at all.
I have it turned all the way CCW and use the output transformer "Presence" control and the tilt control to dial in how much treble I want. Then I can add a bit of treble control but it never gets above around 9 o'clock. I find I can get pretty darn close to the cranked plexi sound.
The closest thing as far as a "real" plexi it could be compared to would the Marshal Studio series SV20H, which is made in the UK and is a miniaturized 20 watt SLP. Listening to both, I think the SV20H is the better amp, but it's not $900 better. I'd say the Origin 20H sounds about 95% of the SV20H and for ~$600 is a great value.
The only downside I've had so far is that it's a pretty noisy amp. (demonstrated in the demo). But I'm not sure if it's inherent to the amp or the way I have my amps set up, I may need to try isolating it from the power circuit my other amps are on.
Anyway, in the demo, I'm running the pedal through the clean setting on my VHT D-Fifty as I typically do. Then I added a section at the end with my Origin 20 for comparison so you can hear pedal vs amp. They're not identical sounding but both are convincingly plexi.
I went with a gold 125B because the board while narrow enough to fit in a 1590B is a bit on the long side.
I also used Marshall knobs to complete the look.
Super easy build, low parts count.
This is their take on an MIAB or more accurately a PIAB, or even more accurate an SLPIAB hahaha.
Boy, was I wrong about being ambivalent....this might be the best Plexi in a box pedal I've ever heard!
Just about every MIAB pedal I've built so far, while sounding good, have a couple things in common, too much bass and too much gain.
My favorite so far has been the Golden Falk, as you can dial a lot of that bass out by adjusting the Treble Gain and Bass Gain channel ratio. But it's still got way too much gain to be considered a Plexi in a box. (Even though its got a JTM/SLP/JCM toggle.
The ROG Thor is a true Plexi in a box. It's not a super high gain pedal but does an amazing job capturing a cranked Plexi. It's voiced very well that you really don't miss the lack of dedicated tone controls. There are two toggles, a "high cap" toggle that simulates the high cap on a Plexi that kicks in as you turn the treble control down on the amp, and it's also got a Bass toggle that simulates running through a 4x12 cab.
If you're a Marshall pedal fan, this a highly recommended build. Here's the write up on the design notes for this circuit from the ROG dudes.
I biased Q1 and Q2 according to this article (6.4v and 4.5v respectively) and it sounds perfect!
In my demo I did some comparisons with an actual cranked plexi amp (well not a true plexi but a Marshall Origin 20) and honestly, I'm a bit torn between whether pedal or the amp sounds more like a real SLP.
About the amp:
I picked this up recently but didn't post about it because I wasn't sure if I was going to keep it. Still not sure actually heh. But I got it for a steal and should be able to flip it pretty easy and be whole. The Origin series of amps seem to be pretty polarizing in the Marshall world. Seems like folks either love it or hate it.
It's part of Marshall's budget line of "vintage style" amps built overseas (in Vietnam I think). Aside from the usual snobbery for anything not hand wired in the UK, it's a unique circuit and take on getting the Plexi sound, which is what it's designed to do. It has some modern amenities like a master volume and an efx loop.
One of the more common complaints is that it's a bit bright and harsh. If you try to approach it like a real plexi it does indeed sound a bit harsh. But there are some easy configuration hacks to compensate for that. I've found that the master vol is kinda useless in the traditional sense. So the way I run it, is to pretty much dime the master and control the level via the preamp gain control. Also, in lieu of a Treble Gain and Bass Gain, the amp is internally jumpered and uses a TILT control that allows you to blend the two channels to taste. I find this extremely intuitive and love it. The last little hack is to not use the treble control at all.
I have it turned all the way CCW and use the output transformer "Presence" control and the tilt control to dial in how much treble I want. Then I can add a bit of treble control but it never gets above around 9 o'clock. I find I can get pretty darn close to the cranked plexi sound.
The closest thing as far as a "real" plexi it could be compared to would the Marshal Studio series SV20H, which is made in the UK and is a miniaturized 20 watt SLP. Listening to both, I think the SV20H is the better amp, but it's not $900 better. I'd say the Origin 20H sounds about 95% of the SV20H and for ~$600 is a great value.
The only downside I've had so far is that it's a pretty noisy amp. (demonstrated in the demo). But I'm not sure if it's inherent to the amp or the way I have my amps set up, I may need to try isolating it from the power circuit my other amps are on.
Anyway, in the demo, I'm running the pedal through the clean setting on my VHT D-Fifty as I typically do. Then I added a section at the end with my Origin 20 for comparison so you can hear pedal vs amp. They're not identical sounding but both are convincingly plexi.
I went with a gold 125B because the board while narrow enough to fit in a 1590B is a bit on the long side.
I also used Marshall knobs to complete the look.
Super easy build, low parts count.
