I remember my first experience with guitar amp and cab simulation software was Line-6 Amp Farm on a now ancient Pro Tools HD-TDM system. And to say it was “un-rewarding” to play is an understatement. However, in the 20-some-odd years that have passed since, software amp modelling and impulse responses have come a very long way, and the new MLC Subzero 100 from Bogren Digital is pretty much the pinnacle of what is possible right here, right now in mid-2023 when it comes to tone and feel for modern guitar tones. Let's take a look around and see and hear what’s what…

Like most guitar sim style products MLC Subzero 100 can either function as a stand-alone application or as I’m running it, as a plugin inside your DAW. Bogren Digital have departed from their usual approach of “one-knob” style plugins to give us a very fully featured electric guitar playback and recording platform. I think it’s safe to say MLC is tailored to the more high gain players, but there is plenty in there for us 70s and 80s rock fans too.

Pre-Amp Pedals

The MLC user interface is divided up into 5 main sections accessed from the icons along the top.

Firstly, we have 2 drive pedals, which are placed before the virtual amp. The MLC Vanilla Sky is a TubeScreamer style drive and the Fascination Street OVD-1 offers tones from a good solid overdrive to something with a lot more gain.

The Amp Head

The second tab accesses the main amp head controls. Starting far left we have the power or bypass switch, the setting for the amps built-in gate, which is very handy when you have the amp set to high gain. We then have power amp presence and depth controls and a low/hi Feed switch selection which controls the amp feedback. In the centre of the amp head we have the primary input gain and volume controls. This is where the balance between gain and volume really pays off. If you want it dirty, turn the gain up and the volume down. If you want it cleaner, turn the gain down and the volume up to balance the signal going into the EQ stages.

The EQ is a straightforward Bass, Middle and Treble cut and boost affair with an added M45 switch, which reduces the gain to emulate a British (read Marshall) style circuit.

The Bright switch with its 3 options (type 1, 2 or off) adds a nice top end shine to the tone, which is especially lovely on cleaner tones.

Moving to the right we have the power amp section with power amp valve (or tube) selector switch. 6L6 will give a darker tone when compared to the brighter EL34 setting. The Master volume is as you would expect controls the main output level into the next stage of the amp sim.

Finally, far right we have the channel selector. Channel 1 can be anything from crystal clean all the way to a reasonable drive tone. Channel 2 is a kind of crunchy drive tone, thing 80’s JCM 800 up to a nice rock lead tone and channel 3 is a full beans US style high gain amp.

All three channels use the same control layout however, each channel has its own settings. So no need to worry, if you like lots of mid in your drive tones but like it dialled back from your cleans MLC has you sorted.

IRDX

The third tab is where MLC Subzero really picks up the metaphorical Amp Sim ball and runs off with it into the next virtual AI-driven ballpark. So much of the guitar tone comes from the combination of the speaker cabinet, the microphones you use to mic the cab and the position you put them in, and yet so many guitar amp sim applications get it so wrong (in my humble opinion). Bogren Digital, however have created IRDX or Impulse Response Dynamix.

Up until now, the IR or Impulse Response was the standard way to “capture” the tone of a speaker cab. You could then load this IR into software or hardware devices and use the sound of your virtual cab for your guitar playback. The only problem is that these IR’s can sound a bit lifeless. IRDX uses machine learning to allow IRs to react dynamically adding subtle speaker movement, compression and distortion to make the cab much more guitar-friendly. And while Subzero 100 ships with both a Vintage and Modern style virtual cabinet, you can also load your own IRs and apply the IRDX technology to them, making all your current IRs, which you may have bought and paid hard-earned cash for, sound amazing. You can load 2 speakers or IRs at a time, and then you can mic them with 1 of 5 virtual mics per speaker. You can then, with a combination of drag and drop, sliders and dials move the mics to create your desired tone.

IRDX is not just a set-it-and-forget thing either. If you find that it is not to your liking, you can dial it back using the large pot at the bottom on the window or turn it off. But hey, don’t do that, it sounds and feels amazing to play through.

Studio EQ

The fourth tab gives us a studio-quality 10 band graphic EQ with +/- 12dB of gain. Unlike the amp EQ this is a global EQ. So if you need to roll out some low-end for a mix across the board, this is where to do it.

Stereo Effects

The final tab is where we find our post amp and cab time based effects. Max Delay is a very nice stereo delay with easy to dial in guitar-friendly controls. WetVerb is a very flexible stereo reverb offering everything from nice tight reflections to massive hall-type verbs. While there is no reverb type control (Plate, Hall, Chamber etc) we do get both size and pre-delay control to help us dial in the required space.

It’s All About Tone

Any plugin or app can have the greatest feature set in the known universe, but if it doesn’t cut it when it comes to sound, who is going to bother? Well, I am very pleased to say that the team at Bogren Digital have nailed MLC Subzero when it comes to tone, playability and feel.

MLC feels like playing through a really nice valve/tube amp. For me, this amp sim is aimed at the high-gain player. You can dial in some really sweet clean on the edge of breakup style tones, but where MLC really sings is the super high gain lead and rhythm tones.

I love the phrase “keep it simple stupid” and I love the idea of one-knob plugins, but sometimes you do need to be able to dig in deep into a tone and tweak and MLC gives you just enough tweekability to make a difference. All the buttons, knobs and switches do the thing you expect them to you, and to my ears at least, all the options sound good.

Take a listen to the audio tracks below and watch and listen to the video to hear some of the tones that I pulled out of MLC Subzero 100.

What’s Missing?

The beauty of plugins and software is that additions and new features are only an update away and while I don’t want a full multi-effects processor of effects and pedals, a compressor on the front end to add some sustain and a Chorus or some kind of modulation effect on the stereo end of things would pretty much make Subzero my go-to software amp sim.

It's A Heavy Load!

Modern-day computers, even laptops have immense processing power on tap whenever we need it. Worries about hardware buffer size are all but a thing of the past, however, MLC Subzero is quite a thirsty plugin when you are using a lot of them (for this track I had six instances running at once). This did not affect the performance of the machine in record or playback but I did notice the Pro Tools performance monitors darting about a bit. On playback, even with the buffer set to 32 samples and six instances of MLC Subzero running my 2021 M1 Mac Book Pro handled the session perfectly well never hitting about 45% CPU usage. However, if you do find your PC or Mac running out of steam you can switch off Ultra Quality mode, which is a little slider in the bottom right corner of the GUI. This reduces the load on your machine by between 5 and 10% with no real audible effect on the playback quality. So, if you are stacking guitars in a mix, this might be your ‘get out of jail free’ card.

Standalone or DAW Plugin?

From inside the DAW you also get access to a large-scale LED-style tuner (every guitar sim should have a tuner) but in the standalone version of MLC you also get a metronome, which is a very handy practice tool but an essential when paired with the built in recorder. This is great for catching those moments of musical genius that always strike when your DAW is playing the game.

Conclusion

MLC Subzero 100 from Bogren Digital is a very, very good modern day amp sim with all the features, functionality and tonal quality you need to record and produce amazing guitar parts. Is it every amp, effect or processor imaginable? Well no, but do I need that in my life? Also no. If you, like me like your guitar parts loud and dirty, you have an up-to-date PC or Mac and you want to make music, either with or without a DAW then you really should check it out at the link below. You will be very glad you did. Now, as a Marshall magazine advert from the 90’s read, “Reach out and hurt somebody.”