Product review - PM40 PianoMic System
I have had the privilege of working with many professional pianists in both studio and live performance situations. I have found that to achieve the ideal grand piano sound it has been necessary to experiment with various microphones in a number of different placements. In the studio, where time isn't as limited, there is more opportunity to try different options to suit the track you're working on as opposed to a live situation where it is very hard to get a consistently great sound from an acoustic piano without incurring feedback and mic separation issues.
Earthworks have listened to engineers and developed this single purpose system to mic a piano for churches, performing arts centres, and recording studios.
Overview
The PianoMic System mounts inside the piano across the strings, behind the hammers. The microphones are supported by a telescopic bar that sits on both sides of the piano case resulting in no mic stands being on view, this also allows the lid to be shut if desired. The whole unit is very light-weight, weighing only 350g, but is very strong and versatile. The telescopic bar is adjustable at both ends allowing a bias to either the higher or lower keys, and when fully extended will reach 64" enabling it to fit all grand pianos.
The two high definition, omni-directional microphones are mounted on the bar with exible stems giving you an incredible amount of positioning from what appears to be a very specifically placed rig. The microphones themselves are a continuation of the Earthworks well-established High Definition mic range with an incredible frequency response of 9Hz-40kHz and a high SPL of 148db. The connections from the microphones are neatly laid inside the telescopic bar appearing at one end with a cable utilising a 5-pin XLR connection. Included with the mic rig, in its rather nice ight case, is a box containing low distortion electronics to split the 5-pin XLR into two standard XLR connections.
Operation
The rig comes out of the ight case almost ready to go. You simply extend the bar to fit the piano and position the mics three inches away from the hammers and three inches above the strings, as Earthworks suggests for a good starting point. The cable can be easily hidden behind the piano and the splitter box can either be mounted on a short mic stand next to the piano or strapped to the piano leg in a neat leather pouch. Connect your two XLR cables, apply phantom power, and off you go.
This layout has all been thought through very well, as it's very adaptable and more versatile than I had first imagined. Everything is all out of sight, which makes it ideal for filming and concert applications. It also permits you to close the lid or to have the lid on either half or quarter stick. By closing the lid it dramatically increases the separation from other instruments or any monitoring in a live situation, or when recording ensembles.
In Use
As you are probably wondering like I first did, when I saw the PM40 it was hard to believe you could get such a good result from miking a piano inside so close to the strings. Conventional miking techniques suggest a piano is best miked from outside. I have played with mics in and around the piano and usually find a ?nasty mush' in the mid range, but the PM40 even with the lid closed delivers excellent clarity. The quality of the sound coming across the PA was very impressive, but better still the sound of the mics in the studio environment was very controlled and clear without the use of any processing. I was also very impressed that the complete note range of the piano could be heard evenly. You may think that there would be a rise and fall in the attenuation of the notes as the pianist plays up to and away from the mics, but this was not the case.
The sound of the piano with the lid closed is a little more boxy as you would expect, but is still very acceptable and in some cases more desirable. We had the lid open whilst testing the Yamaha C6 grand piano at High Barn (www.high-barn.com) and I tried raising the mics as high as the stems would allow and noticed the natural reverberation of the room was audible. When the lid was closed and the mics were close to the hammers, the PM40 gave us a very clear bright rock-piano sound, which fitted comfortably in a mix for a rhythm and blues band performing at the venue.
The gain before feedback level of the PM40 is much higher than anything I have ever used on the stage. However, the mics have such a low frequency response to try and capture as much of the image as possible from the piano soundboard that it's the low frequencies that feed back first. I can't help but feel that by being able to change the frequency response and/or the polar patterns with various price options, the unit would be more sustainable in the live sound industry. To get the piano at the level we needed I had to compromise on the lower end of the EQ. However in my opinion, it did sound great in the studio and is better than anything else I've used for live recording.
Conclusion
This is something we've all been waiting for. Earthworks has done an incredible job and for those that are always needing to mic an acoustic grand piano, I believe this is the solution you need. The clarity and versatility of the PM40 is second to none and will surprise the most experienced of engineers. The only thing I would urge you to consider is the price.


