Let’s talk about the room - Part I

When we think about improving our recorded sound, we usually think about upgrades in gear; we lust for new microphones, interfaces, guitars, etc. We don't want to buy new things; we absolutely need them. Sometimes, we even postpone recording altogether until we have the budget for purchasing said gear.

The harsh truth that we sometimes don't want to admit is that spending more money on gear will not fix fundamental issues. Getting a good sound in the room before we hit record is essential, as essentially, this is the sound that our microphones hear and our interfaces capture. Fix it in the mix does not apply with classical guitar recordings wherein room and performer are equally exposed.

Having used all sorts of gear in all possible situations, I rank all the elements of the recording chain in this order: guitarist, guitar, room, microphones, engineer, playback system, post-production skills, preamps, converters, cables. Leaving everything else aside, in this article, I examine a few ways to get the best out of a typical residential room without spending any money.

Disclaimer - room treatment can be approached from a more technical standpoint which I plan to discuss here in the future. Contrarily to what the vendors of acoustic panels will say, household items can be used as a pragmatic alternative, even more so considering the singular commitment of a classical guitar recording space.

First. The sitting position.

Sometimes out of being lazy or just practical, we set up everything as is and keep the room as we would normally use it, especially if we don't have a dedicated music room. Considering the degree that the room affects the recorded sound, searching for a suitable sitting position should not be overlooked.

Before all else, when I enter a new space for a session, I try to figure out the best sounding position in the room. This habit applies both for on-location to home recordings and even concerts to some degree. I'm not getting into detail about on-location recordings and big spaces now, as this goes beyond the purpose of this text.

I have assembled a few guidelines to help you search for the perfect sitting position in your room but keep in mind that every room has unique sound properties.

First of all, you want to avoid sitting close to the walls and most definitely steer clear of the corners; the build-up of low frequencies and the early reflections will cloud the direct sound of the guitar. Also, the centre of the room is far from an ideal sitting position, especially in a room with parallel walls.

In an ordinary rectangular room, if possible, you'd want to sit alongside the long walls about three-fourths to two-thirds of the length of the room. In addition, I find that sitting a bit off-centre and facing the front wall at a slight angle towards the longest distance produces the best results; this modest break of symmetry helps.

Nonetheless, you need to experiment with your space as every room is different. Perhaps asking someone else to play your guitar in a couple of different positions and try to listen is not a bad idea. If this is not possible, pay attention to the sound while you play; singing can also assist you in identifying the room modes. Moreover, you'll need to record yourself in various spots and listen critically; recording the same piece can make comparisons less ambiguous.

What you are looking for is the most balanced sound; play all notes of your guitar in sequence as well as your favourite piece, and if it gets boomy or any frequency stands out a lot, try a few different angles or move a little. If the room is untreated, which probably is, the result will not be outstanding, but in any case, it is worth finding the position where standing waves are not encouraged, then acoustic treatment can be employed.

Second. Other uses for your books.

Speaking of acoustic treatment, this goes without saying, at least to some extent. But, as our rooms usually serve (at least) a dual purpose, a playing/recording space along with a listening/production room, some compromises have to be made. Critical listening requires a controlled environment, while what makes a good room for recording acoustic instruments can be partially subjective.

I have recorded in all sorts of situations, from big halls with a vast reverberation to heavily treated studios with no ambience at all as well as everything in between, thus I have concluded that I genuinely don't enjoy playing in an acoustically dead room. Even if the captured sound in such a controlled room is somewhat easier to handle, the performance and feel of the music always take a big hit. Clever microphone placement and good post-production skills can make almost any room sound acceptable, contrary there is nothing we can do to improve an uninspiring performance.

Thankfully, the classical guitar is not the loudest instrument around, with a lot of its energy residing is in the mids and highs, so it is not impossible to minimize the small room sound signature. Whilst is more convenient to record at home, on-location recording is never out of the question; I could always visit one of the exceptional sounding halls in Berlin or elsewhere when absolute sound is required. It is also refreshing to work on other rooms.

Wherein large rooms we have to deal with diffuse sound fields, which pose their challenges anyway, small rooms suffer from early reflections and resonances associated with standing waves. Dealing with the low frequencies below 300Hz is rather troublesome as wavelengths are large and spread omnidirectionally, while higher frequencies behave more like rays.

The key here is to use a combination of diffusion and absorption strategically. Since broadband diffusers and absorbers can get expensive fast and need to be quite thick to have any effect at the low-mid and low frequencies, there is a free alternative you can use effectively: books.

Books placed on shelves create an uneven surface, forming some sort of diffuser from which sound waves are reflected in different directions. Moreover, paper absorbs some of the sound energy, so a bookshelf works in addition as an absorber.

Gather your books and build a bookshelf on the front-facing wall (in the typical control room, the front wall is considered the one where the monitors are placed, here I use the term to indicate the wall you face when you play your guitar). Use different book sizes and thicknesses, and experiment on the relative depths; this bookshelf will absorb and scatter the sound in the room while maintaining some liveliness.

Admittingly, a bookshelf won't do much to the lower frequencies, and its properties will be somewhat random. However, you probably have plenty of books in your household already, and a bookshelf is more eye-pleasing. Plus, they are nice to read from time to time.

Third. The floor.

Since the guitar hangs in closer proximity to the floor than any other reflective surface around you, bouncing frequencies would cloud the direct sound. Also, the somewhat low ceilings and small dimensions of residential rooms dictate for closer and lower microphone positioning that say a concert hall, thus heightening the problem.

To tame the room ambience to a certain degree, place a rug between your guitar and the microphones. Avoid covering the whole room with a carpet, but rather use a small to medium-sized one.

Experiment with a few different sizes and thicknesses until you find what works in your space. Your goal is to allow the microphones to capture a cleaner sound while maintaining the room ambience. The absorption will only be effective at the high frequencies. I use a woollen rug of medium thickness that extends from just under my seating position to a bit further than the position of the microphone stand.

Closing

With the advancement in technology over the last twenty years, quality recording equipment has become pretty affordable consequently capturing compelling recordings at home is no longer impossible. However, we should not forget that the microphones capture the sound of our guitars in our rooms. So, be intentional and learn trust your ears.