ShroomTech Microphone NC Controller

ShroomTech say the remote control can operate the robot from 100m away.

Ever dreamed of having a robotic studio assistant? Polish company ShroomTech have made that dream a reality...

As anyone who’s done even a little bit of recording with a microphone should know, moving the microphone in relation to the source you’re capturing can make a great deal of difference to the sound. The traditional method has always been to place your mic about the source — be that an instrument, singer, amp or whatever — then listen, then adjust the placement to taste. If you have someone to assist, this can be quite straightforward; you direct them in moving the mic whilst listening to the sound over your monitors in the control room. If you’re flying solo, though, it can quickly become tedious — you either have to keep walking between rooms making small adjustments (which can suck the life out of a session, and potentially lead you to make do with an OK sound instead of a great one), or to attempt to separate the sound you’re hearing over headphones from the sound in the room, which is always going to be a compromise.

As trying as all that may sound, getting the sound right at source in this way is an essential part of the recording craft, and one which will result in much less need for processing and frustration further down the line. Thus, I’ve always thought that some kind of mechanical tool that made mic placement less of a chore could be very useful for a modern studio — and as I almost never have the luxury of an assistant on the sessions I run at Half Ton Studio, I was very intrigued to see how a ‘mic robot’ would fit into my workflow.

Pole Positioner

ShroomTech are a Polish design and engineering company who offer both bespoke products and standard configurations of remotely operated ‘Microphone Controller’ to suit various needs and budgets. They’re all similar, being based on stepper motors and a series of belts that allow the mic to be moved along one or more axes. There’s also the option of a rotating microphone mount.

You can choose how sophisticated you want your robot to be depending on how many axes you want to be able to move your microphone in and over what distance. For the most basic two-axis model, for example, you can remotely move your mic from left to right and backward and forwards. For the three-axis model, you also have the ability to rotate the microphone’s mount by up to 360 degrees. There is also a four-axis model which allows you add to add up and down movement too — which should have you pretty much fully covered! But it’s worth noting that the more options you add, the bulkier your ‘robot’ becomes. I decided to test the three-axis version, as this is the lowest-priced model to feature all the different options (the up-down mechanism is the same as used for forward/backward and left/right movement).

The whole assembly is controlled remotely and wirelessly via a small hand-held box — in the case of the three-axis version this features a small joystick to control the movement on the two linear axes, and a single rotating pot to control the rotation of the mic mount. The main ‘robot’ is mains powered, and the box accepts both a PP3 9V battery (for wireless use) and USB, which might be useful if the controller becomes a fixture in your control room.

First Impressions

The main mechanical device is quite bulky, and you have to find a suitable mic stand to attach it to — and that requires a little contemplation! After a little trial and error, I found that by using the base of a short boom stand to hold the device, I was able to attach the boom arm to the top of the robot to hold the microphone. Using this boom arm to hold the mic seems essential to me, as without it you‘d constantly find yourself trying to get the robot up to the right height in relation to the source.

The remote control is small and compact — it fits in the palm of your hand — but, for the review model at least, the build quality felt like that of a prototype; a few bits of glue were still visible, the control pot could easily be pulled off, and so on. But while it would be nice to see a more polished finish, functionally it was fine. Once I had the robot on the stand, I was able to power it up and get my bearings in terms of controlling the movement of my chosen microphone.

Tried & Tested

By far the most obvious use for such a device, for me personally at any rate, would be when miking up a guitar cab, because even small movements in mic placement and orientation can make a big difference in tone. When I received the ShroomTech unit, I happened to be working on a session that involved quite a lot of re-amping of DI’d guitars that my client had recorded at home, so it seemed like the perfect opportunity to put the robot into action.

When you first plug the device in, you’ll have a lot of fun as you start to get a feel for how the mic placement can be controlled. Stepper motors aren’t what I’d call quiet; despite being visually quite smooth, there’s an inherent amount of motor noise which I’ll talk more about later. The 360-degree rotating pivot moves in slightly ‘jerky’ increments, but although this initially seems a bit crude it was actually quite effective in use. There are no markings to tell you which direction the control box will move the mic — presumably because there’s no ‘front’ to the robot — so it took a little trial and error to get the hang of which direction controlled which axis. (I was always rubbish at computer games, so others may find this less challenging!) I didn’t get a chance to test the full range of the wireless connection between remote and robot, but I certainly had no problem using the box in my control room, with the robot in the live room, throughout the review period. ShroomTech claim it can work up to a range of 100m, which would be plenty for pretty much any application I can conceive of for this device. There are other robots available which can be controlled via a smartphone over Wi-Fi. ShroomTech’s don’t allow that, but that’s not necessarily a bad thing: there’s a certain attraction in having a dedicated control that can be left permanently set up in your control room.

I used a single Shure SM57 mic and positioned the robot so that the mic was pointing straight towards the middle of the speaker cone and almost right up to the grille. With some guitar signal now being played via the speaker in question, I was able to begin experimenting with mic placement from the comfort of my control room. I initially had to discipline myself a bit — there’s definitely a ‘boy with his new toy’ factor in your first session with the robot — but soon found it intuitive, and it worked well for this track. The song in question had quite a few layers of electric guitars that needed re-amping, and I felt that it was important to have some variation in tone between the multiple takes. If the guitar felt a little bright, rather than reach for EQ or run around to the live room, I was able to move the mic an inch or two away from the middle of the speaker cone. If things felt a little harsh, I could rotate the mic so that it was a little off axis, and I could create a little difference between double tracks by moving the mic slightly backward instead of reaching for EQ or an alternative mic. It was all very immediate.

Staying with guitar recording, another obvious use for me was trying to use the robot to improve the phase coherence between two microphones. I tried this on two different occasions, and on the session where I could also visually see the mic through the control-room window I was able to dial in a really effective paring of a close and a more distant mic on a guitar cab. I tried a similar technique on another session when the cab was in a room without a window, though, and I found it hard to get it to work without being able to see the movement of the mic. This is something you might get used to, I suppose, but it is food for thought. That said, if you have recording rooms you can’t see from your mix position, it’s very cheap and easy to set up a simple camera system these days!

I was also keen to try the system with a kick-drum mic during a multitrack drum recording session. This is one of the situations where I often find myself doing a lot of walking between the live and control rooms, tweaking mic placement. And while there’s an argument that you should grab whatever exercise you can get if you work in a studio, I figured there was potential to improve my productivity and results here! While the robot should, in theory, have worked well in this role, I encountered a couple of hurdles: the first was that the robot, being physically quite large, took up most of the real estate immediately outside of the kick drum. This wasn’t a huge problem, but it did mean I had to work around it a bit; if I had another mic outside the drum, for example, it would make positioning this tricky. The other issue was that I could clearly hear the mechanical noise from the stepper motors through the drum mics when I was auditioning placement. This meant that I had to move the mic and then stop and listen rather than auditioning it in real time — it’s not that it was impossible, and the robot did help me find a good spot, but it just wasn’t as satisfying to use as it was on my guitar recording sessions. I had a similar experience when I used it for an acoustic guitar, but again, while it was perhaps less immediately satisfying as when used on electric guitar, I arrived at a good sound and it certainly saved me a couple of trips between rooms.

I, Robot?

When I was recording guitars cabinets, I found the mic controller to be a genuinely useful tool. I found myself using less EQ at both the tracking and mixing stages, and for the session with multiple guitar takes it really felt as though it helped me work faster and more efficiently. Just using it for a brief period has reinforced my understanding of how different areas of a speaker cone can shape the tone of a guitar recording. So if a lot of your recording duties are based around recording electric guitars, or if you like to do a lot of reamping, then I think this device could have much more than a novelty value. Other applications where I think it could be useful include certain drums, bass guitar cabs, or any instrument where the mic doesn’t practically need to be above, say, waist height. You’d need a very sturdy mic stand to allow that — though of course such stands do exist...

The review model worked perfectly throughout the review period, but ultimately, in terms of my workflow, the concept wasn’t a game changer for me. I have to change the setup in my recording room almost daily, and it’s used by various engineers and clients, and that made storage a bit of an issue — it became a bit of a pain to find somewhere to put the quite bulky setup, and I wouldn’t really want to keep taking it on and off the mic stand. That said, I would still recommend giving one a try, particularly if you have a more static recording setup, or if you do a lot of re-amping in particular. As a last thought, I should mention that it does have a certain wow factor — my clients were always very impressed when they saw it in action!