Comparing playback formats for backing tracks

(The original version of this article was first published on the Mp3 Backing Trax website circa 2006 – 2012)

Warning – choosing the wrong backing track format could seriously damage your performance!

Which format should you use to play backing tracks?
There has been much debate about which format is the best for the playback of backing tracks and I hope that in this article I can separate the fact from the fiction and dispel many of the myths you may have heard regarding different formats.

The first thing you should be aware of is that most musicians and singers tend to be creatures of habit. They don’t like change, especially to the way they work on stage, so if you ask any fellow singers or musicians what the best format is for playing backing tracks (eg mp3, CD, minidisc, or midi) don’t be surprised if you get a totally biased opinion from them – I’ll hazzard a guess that they’ll probably advise you to use the same format that they use!

This is not necessarily the best format format for you.

I know of one singer who still uses cassette tapes. Yes, they’re a nightmare to cue up and all hissy and horrible, but he’s been using them since the mid-seventies, he’s comfortable with them and refuses to change!

So, if you want an unbiased opinion on audio formats for backing tracks, read on…

Quality and ease of use onstage are the key
There are two criteria you should consider when choosing a backing track format. The quality of the backing track has to be good enough for your purposes. Next, the ease of use in which you can select songs and begin playback of them during a live performance is critical (especially when you will constantly be singing in environments where there’s flashing lights, a high-energy atmosphere and the adrenalin is flowing).

For both quality and ease of use reasons, we will totally dismiss cassette tapes – they are unsuitable for backing tracks. They are noisy, hissy, regularly go out of pitch and take valuable seconds (often minutes) to cue up to the next song. Even if you use a double-cassette or two cassette decks, you will still spend more time working the machines than working your audience – take our advice and forget you even ever heard the word cassette!

CD is the best quality – no if’s or but’s. CD is un-compressed audio so gives the best quality of all formats and it’s also the standard by which all other music formats are measured. But before you opt for CD, it has some serious drawbacks when you’re using it “live” so please read this full article before making any decisions!

Minidisc is compressed music at a quality ratio of 5:1. What this means is that the audio signal has been squeezed down to 20% of it’s original size. The advantage of this is that you can fit 15 – 20 songs on to one of those tiny little minidiscs which are a fraction of the size of a CD.

Minidisc is also an enclosed format so unlike CD, it won’t be prone to fingermarks and scratches etc which can cause skipping during playback.

Although the minidisc song you are hearing has been compressed, in tests most human ears cannot tell the difference between minidisc and full CD quality, even when using high quality sensitive ear-phones.

Midifiles are only as good quality as the musical instruments you are playing them on because they are not actual audio files – midi is only a stream of digital data which tells the instrument that it’s connected to what notes to play (a little like one of those old player-pianos which used rolls of paper with little holes punched in them and appeared to “play itself”).

Midi should only be used for backing track playback if you are an accomplished musician/sequencer and know how to manipulate these files properly, because if you don’t, midifiles can sound very cheap and nasty.

MP3 encoded at 320kb/s is a ratio of 4:1 so mp3 at a 320kb/s bit-rate) is better quality than minidisc.

Although it may seem strange, just about everywhere you look you will see that mp3 is generally encoded at a bit-rate of 128kb/s which is actually a ratio of 10:1. You’ll often see 128kb/s described as “CD quality” but technically that’s just not true (as CD is un-compressed – ie 1:1 ratio).

However there seems to be no doubt that the majority of the music listening world is happy to term mp3 encoded at 128kb/s “CD quality”. What this really boils down to is that most members of the general public can’t hear any discernable difference in quality between a CD and an mp3.

This makes sense too because mp3 works by discarding the frequencies that the human ear can’t hear. That’s how it manages to compress the music. It “throws away” stuff that is outwith the human audio range, working on the idea that your ear can’t hear these frequencies anyway,

The other advantage of this is that there should be no ultra-high frequencies that can blow your speakers horns or bass rumbles that can blow your bass bins – mp3 has taken these “dangerous” frequencies out of the audio spectrum… mp3 could help protect your PA system as well as giving you great quality.

Ease of use “Live” onstage
CD, minidisc and mp3 all give quality which is, without doubt, more than good enough for “live” performance. In a “live” onstage situation, we defy anyone, even with the most highly trained ear, to tell them apart, However, they are not all as easy to physically use onstage.

CD should be avoided at all costs. The fingermarks and scratches that can get on to CD’s will cause skipping and even just one little skip while you’re singing a song will throw you off completely. CD will make you look totally unprofessional as the audience wait for your next song while you wipe the next CD you’re about to load with a soft cloth (or maybe your shirt or blouse!).

It’s just not good enough and loading CD’s in to a CD player during a performance will make you look loke some amateur karaoke singer rather than a profesional entertainer. Not recommended!

Midi can be used quite effectively “live”. You have control over the individual instruments sound and if you have an expensive music keyboard or module with a SD card, usb, hard-disk, or zip drive, you don’t need to swap floppy discs half-way through a performance etc.

Remember though, the sound of a midifile will only be good if you have very expensive, high quality musical instruments to play it through and you have programmed the midifile to suit the sounds in those instruments.

While onstage, if you’re using a midifile, you will find yourself spending a lot of time on your mixing desk rather than concentrating on your audience as it’s a lot of work to balance all the bass, drums, brass, guitar etc etc for every instrument on every song (yes, I know these should already be pre-balanced but the fact is that different venues have different acoustics and you will always have to make adjustments everytime you perform).

Also, you really need to be musically proficient in programming, playing and sound engineering to get that all important “good sound” so they are not recommend for non-musician solo singers.

Minidisc is much easier to use onstage than midi and CD. It is an enclosed format which means that you don’t have to worry about scratches and fingermarks and each song can be named, instantly located and cued up to play in seconds.

It’s stereo so there are only two cables required to connect it to your PA system (left + right) so you can set up quickly.

The disadvantage of minidisc though is that they can only hold 15 – 20 songs so you have to turn your back on your audience from time to time to load up a different disc.

Also, you have to wait till one song is finished before you can cue up the next song. Although this probably doesn’t sound like a a major problem, believe me, sometimes that couple of seconds it takes to find the next song can be crucial in a live situation.

Up until a few years ago, minidisc was the most popular format for playing backing tracks but it has now been overtaken by mp3. That’s because mp3 has all the advantages of minidisc but none of the disadvantages (see next paragraph).

MP3, like minidisc, allows you to instantly access the songs stored on it so is ideal for onstage use. Many MP3 players can hold 10,000 or more songs (compare that to the paltry 20 songs a minidisc holds!) and you can navigate to any particular song on an mp3 player just as quickly as you can scroll through songs on a minidisc, sometimes quicker.

In addition to this, mp3 lets you create playlists (set-lists) etc – you can’t do that with minidisc without unprotecting the minidisc and “moving” the songs in to a different order.

Also, you need to “swap” minidiscs during a performance which can cause embarrassing silences during your set but with an mp3 player you can have thousands songs at your fingertips and, most importantly, you can cue up the next song while the present song is still playing…

I reckon, without doubt, that mp3 is the best format of all for playing backing tracks. It is streets ahead of any other format for playing backing tracks and has all the advantages of every other other format and in addition to this, addresses and solves all the issues and disadvantages of these other formats.

There are no moving parts in an mp3 file so it’s more reliable, it’s kinder to your speakers & amplifiers, it gives fantastic quality, it’s smaller, more manageable, and easier to use…need I go on further?!