This sketch shows one way the various facilities needed in a small studio can be dovetailed into a conventional square block of space
Figure 1: a possible layout plan for a typical small recording studio
A sound mixing console may have 128 or more channels, each consisting of a long column of volume, tone and other controls dedicated to controlling a single sound source
Figure 2: a little over half of a large commercial console (mixing desk) at (and photo courtesy of) Metropolis Studios, London. The studio room on the other side of the glass is shown in the article heading photo. The author did not, sadly, design Metropolis Studios...
For Blumlein stereo recording, two cardioid (directional) microphones usually are used at about a 90 degree inclusive angle. Originally 'figure-of-eight' characteristic mikes were used. Ambisonics uses three 'figure-of eight' mikes in a tetrahedral orientation
Figure 3: here we show the basics of true (Blumlein) stereo recording, and its extension to three dimensions as Ambisonics
The power of the sound sent to each side is cut by half with the pan control in the centre position - as it moves from there, one side gets more level and the other side less
Figure 4: all that we can do on a typical mixing desk is use the pan-pot to set volumes and give a false impression of panoramic position using the Haas effect. Here is part of a typical (measured) quality pan-pot characteristic
A floor plate is mounted on the existing floor with something to absorb vibrations placed (optimistically) between the two surfaces
Figure 5: a floating floor, supported on the existing floor but (we hope) isolated from it. Usually our hopes are confounded...
Here the old floor is untouched. A new floor is placed above it but separated from it, with sound absorbent in the space between
Figure 6: an isolated and floating floor. Here a complete new floor is built, with the original left in place. Then, a floating floor is put on top of the new supports. This works, usually...
The (ideal) sound absorption doubles (at any frequency) as the mass in the diaphragm (floor, wall or ceiling) doubles.
Figure 7: a graph of Sound Reduction Index (SRI) as a function of surface mass. More massive equals more sound loss (and cost!)
The Noise Rating curves require less absorption at lower frequencies than at higher ones. This (very approximately) matches the frequency sensitivity of the human ear, which falls off towards the low end
Figure 8: standard Noise Rating curves. These allow a shorthand way of stating how much noise reduction is needed - you can just specify 'to NR 10' and that says it all. In theory!
The noise levels measured within typical quiet homes are not that different from the standard noise curves above
Figure 9: the Noise Spectrum of average and quiet homes, drawn to the same scale as Figure 8. If you compare this with the NR curves above in Figure 8, then you'll see that you just might be lucky enough to get away without too much work...
The window has three panes of glass, each a different thickness and at different angles, so that they do not act as mirrors for light or parallel reflecting surfaces for sound. The gaps have sound absorbent around the edges
Figure 10: one way of building a studio window. The third pane of glass adds little in practice, but it doesn't add that much to the (already high) cost, so why not...?
A transformer connects two circuits by a magnetic field, so no electrical connection is needed. In this way the 'hum loop' can be broken and all the equipment connected to ground for safety reasons
Figure 11: how to use isolating audio transformers to keep the hum and noise level down and the musicians (and desk engineer) alive. Assuming, of course that that is regarded as important...[that is a JOKE, right? ...I think %-]