I’ve included 4 of the samples below, and I hope you find them useful – and possibly enlightening. Each tests a facet of the two most common monitoring problems in home studios: Uneven bass response, and poor stereo imaging.

Sine wave sweep

Contents: A sine wave sweeping from 40Hz to 300Hz.
Use this to test for: Bass response, sympathetic vibrations.

Unless you’re outdoors, or listening on headphones, you’ll notice the volume rising and falling as the audio plays. That’s normal, although the level doesn’t actually change. (Open the MP3 in your DAW to confirm this.) Rather, you’re exposing the acoustic response of your room.

Use this test as a rough gauge of how extreme the acoustic issues are in your space. (You can flatten the response somewhat, but acoustic treatment is a topic unto itself. For some more information, check the quick backgrounder on home studio acoustics.)

Additionally, the sweep can expose low-frequency dependent rattles, buzzes, or other sympathetic vibrations happening in the area around you. With this test, I once discovered the casing on an overhead light shook at exactly 140Hz, after puzzling with a mix for 15 minutes, unable to isolate the odd rattling sound.

Two octave walk-up

Contents: Consecutive semitones from G1 (46.2Hz) to F3 (174.6Hz)
Use this to test for: Bass response, specific problem notes.

Here, the tone ascends through a chromatic scale. Certain notes will jump out or disappear, for the same reasons as above. Remember these notes, as they’re important to the character of your mixing space. Specifically, when you know that, for example, the B at 61Hz drops in volume in your space, you can reconsider when you find yourself reaching for the fader every time the bass guitar plays B.

5-point pan check

Contents: 5 bursts of white noise at different pan positions.
Use this to test for: Coarse panning issues.

This file plays sound at the center, hard left, hard right, half left, and half right. If you don’t hear 5 separate panning locations, you’ve got stereo issues!

Most stereo imaging problems are caused by incorrect speaker configuration (i.e. the speaker aren’t equal distances from your ears,) and poor room acoustics.

Short-pan test

Contents: White noise at 3 different pan positions.
Use this to test for: Fine panning issues.

This file plays a sound at 50% left, then hard right, then 25% left. (The jump to the right distracts your ear so it can’t track the sound moving from 50% to 25%) The 3 sounds then repeat on the other side.

Most listeners can reliably distinguish 5 or 7 distinct pan positions. So if your stereo imaging is clear across 9 points, i.e. 25% increments, you’re in good shape (for mixing in a home studio, at any rate.)

On the other hand, if the difference from 50% to 25% isn’t clear in your monitors, or is more defined on one side, you might want to consider using headphones to verify your important panning decisions.

Note: Since these test don’t require high fidelity, MP3s should be fine for checking your setup. However, here are links for WAV versions of the test:

Sine Wave Sweep – 40Hz – 300Hz
Consecutive semitones from G1 (46.2Hz) to F3 (174.6Hz)
White noise at 5 pan positions
White noise at 3 pan positions

For more home recording tips,
Subscribe to the Hometracked feed, or receive email updates.

A recent CEA study adds that three quarters of adults online listen to music on their PC:

… penetration of the PC in US households (now estimated at 82%) has more and more consumers looking to their home computer instead of their TV, DVD player or CD player for a home audio experience. 86% of home PC audio users are satisfied with their computer-sourced audio experience.

This study and my informal survey above point to an important truth about mixing: If you know that most listeners consume your music in a specific format, you should ensure your mixes translate well to that format. When your mixes mostly end up as MP3s on iPods and PCs, it makes sense to check the results of your mixing decisions on those devices.

In fact, some argue you should specifically target the destination medium with your mix. For example, many professional engineers produce separate mixes for CD and radio, the latter constructed to hold up under the extreme compression, limiting, and phase rotation that radio stations pass their broadcasts through.

If nothing else, the modern listening habits outlined above suggest you should keep a pair of consumer PC speakers on hand, and periodically check your sound through them. You’ll have confidence that the growing number of listeners who hear your mixes through smaller speakers still enjoy an accurate version of your intentions for the mix.

You’re probably not going to fool anyone but it might be enough to imply the sound of an upright by having (or exaggerating) a few of its distinguishing traits. I think the decay is important. Uprights seem to have less sustain than electric bass. Try the Carol Kaye trick of putting some fabric near the end of the strings (near the bridge is best bet, but you could shove it between the strings and the fretboard at the nut) to dampen them.

Why do CDs use a sample rate of 44.1 KHz?

44.1 kHz came about because digital audio was encoded and then stored as video on video tape as white and black bits.

Since there are a number of video standards a sampling rate had to be chosen that would be divide up well on to video formats having different frame rates and scanned lines per frame.

And more, on the technical details:

Video recorders… were adapted to store audio samples by creating a pseudo-video waveform which would convey binary as black and white levels. The sampling rate of such a system is constrained to relate simply to the field rate and field structure of the television standard used, so that an integer number of samples can be stored on each usable TV line in the field.

What recording chain did John Mayer use on his album Continuum:

Vocals were Mic -> 1073s -> 1176 (or two chs with one into a Fairchild 670)
Neumann U47 (most), Neumann M269c & RCA 77 (“I’m Gonna Find Another You”)

How do you place your monitor speakers? Even if you’re mixing with computer speakers, there’s lots of useful advice here: