How to connect your equipment

From Audacity Manual

Jump to: navigation, search

Connecting your equipment

In general, you need to run an appropriate cable from an output on the external device (for example a tape deck, or an amplifier or receiver connected to a turntable) to the line-in port (not the mic-in port) of the computer. You should not connect a standard turntable directly to a computer - see below for advice on connecting a standalone turntable below. A typical cable you might use is an RCA cable to stereo 3.5mm mini-jack.

Users with high-grade equipment may prefer to use the source device's "aux out", "tape out", "line-out" or "record" output (if so equipped), since those bypass an unnecessary stage of possibly low-quality amplification, and standardize the signal at a fixed (non-adjustable) level of approximately 1 - 1.5 volts, resulting in a higher quality recording.

If you choose this approach, you will need a cable that has dual RCA red/white plugs at one end (for connecting to the "aux out", "tape out" or "record" jack of the device) and a stereo 1/8 inch (3.5 mm) plug at the other end (for connecting to your computer's line-in port).

If your device does not have RCA outputs, the headphone jack is a good output to choose, since it will allow you to adjust the output level of the source device. Typically you will need to use a cable with a 1/8 inch (3.5 mm) stereo jack at one end (for connecting to the device's headphone socket), and an identical 1/8 inch stereo jack on the other end (for connecting to the line-in socket on your computer). If the device you are recording from has a 1/4 inch (6.3 mm) headphone jack, you will need to get a 1/4 to 1/8 inch adapter. Such an adapter is often included free with most new headphones, or can be purchased separately at any good electronics store.

Here is a typical cable you might use for equipment with RCA outputs (an RCA cable to stereo mini-jack):

Photo of an RCA cable to stereo mini-jack

The RCA end might connect to the output jacks in the back of your cassette player:

RCA cable plugged into the back of a cassette tape player.

The stereo-mini end should be connected to your computer's stereo line-in jack, usually found on the back of desktop machines. The line-in is normally colored blue, but check your computer manual.

Computer showing the blue input port for stereo recording

You should not generally connect to the microphone (red) port of the computer.

  • It will excessively amplify the stronger line-level signals produced by a tape deck or receiver/amplifier. This could lead to damage to the port or to your sound device.
  • A microphone port is typically mono. If the port is mono then, even if you connect a stereo input to it and set Audacity to record in stereo, you will only record "dual mono" which has the same content in left and right.

The are only a few exceptions where you should connect to a computer microphone input:

  • On some personal recorders, connecting from a low power minijack intended for connection to the microphone input of a recorder;
  • On some Macs, or some Windows laptops or desktops, connecting to a "switchable" port which can be toggled to line-level stereo. Check your computer manual to see if there is a switch on the computer itself or in the sound card control panel. On a few laptops the line-level source is called "mix" or "stereo mix", but on most machines "stereo mix" will only record computer playback.
  • On recent Windows laptops, notebooks or netbooks, there may be a "compliant" single port which will tolerate line level input and may provide stereo input. Even if stereo, the quality may not be as high as that of a dedicated line-in port.

Always try line-level input first, and only use a microphone input if you cannot otherwise get adequate recording volume. You can buy modestly priced, decent quality USB interfaces with line level stereo input if needs be.

If there is no way to record at line-level, add a line-in by adding a sound card or interface that connects to the computer via USB. Examples of recommendable devices:

Connecting a tape deck

If you wish to record from an audio cassette, or a reel-to-reel tape deck, you can connect that deck directly to your computer without the need for any external amplifier or receiver. Simply connect the deck's "line-out" RCA jacks to your computer's "line in" jack, using a cable described above. You can also connect to the headphones out jack of an integrated cassette deck or to that of an amplifier connected to the tape deck. If you do this (or if the "line-out" volume of your deck is adjustable), it is best to set that level quite close to its maximum, and adjust the recording level using Audacity's input volume slider (see below). This helps keep the inherent tape noise to a minimum in the signal sent to Audacity. If the cassette you are playing has been encoded with Dolby ® as denoted by the Dolby Double-D symbol, then you must enable Dolby playback on your tape deck, or the recording of the tape will sound over-bright.

Before transferring your cassette, you may want to clean and align your tape heads and also clean the transport mechanism (capstan and pinch roller). See the wiki page on Recording from Cassette for more details.

Connecting a standalone turntable

If you have a standalone turntable, you must not connect it directly to your computer. Instead, you must connect it to an amplifier or receiver with a "phono" or turntable input, or to a phono pre-amplifier - and then record from the amplifier's "line out" or "tape out" jacks. This is for two reasons: (1) the audio signals produced by a phono cartridge are too weak to record directly, and (2) most records manufactured from the 1950s onwards were produced with a standard type of equalization called "RIAA", which emphasizes high frequencies and de-emphasizes (reduces) low frequencies. If left uncorrected, this will result in a recording that sounds very "tinny". All amplifiers containing a "phono" stage will both boost the signal to line-level so it's suitable for input into a tape deck or a computer, and will reverse the RIAA equalization so that the records sound "normal" again. If you have an integrated "stack system" or "entertainment center" into which you plug your speakers, your record deck is already connected to a suitable amplifier.

If you have a standalone turntable but no amplifier or pre-amp, you may want to consider the Behringer UFO202 or the ART USBPhonoPlus. These devices contain a built-in phono pre-amp and connect to your computer through a USB port. They can also be used to connect line level devices such as a cassette deck.
Warning icon Advanced technique: it is possible to directly connect a standalone turntable to the line input of a high quality sound card, if you are prepared to perform the amplification and RIAA equalization yourself in Audacity. Effect > Equalization has a suitable RIAA preset.

Discs pre-dating RIAA equalization such as 78 RPMs sound too dull if recorded through a standard amplifier using RIAA playback equalization. A solution is to record without RIAA playback equalization, either by connecting the turntable directly to a sound card with a "high-gain" input, or by using a "flat" amplifier that applies only signal gain. The recorded waveform can then be re-equalized using an appropriate pre-RIAA or 78 RPM playback EQ curve. Suitable curves may be downloaded from the Wiki.

Connecting a USB turntable or USB cassette deck

A USB turntable is a relatively new kind of turntable which is designed to connect directly to your computer's USB port. The concerns noted in the 'standalone turntable' section above do not apply here, as the necessary pre-amplification and RIAA equalization are already built into the USB turntable. There are also USB cassette decks available which are similarly designed to connect directly to your computer's USB port. There are some special playback and recording device settings you need to observe when using USB devices - see Recording with USB turntables or USB cassette decks

Connecting a MiniDisc player

Some users find that the line-level output of MiniDisc players is too strong for recording on a computer and causes distortion, since its level is not adjustable. If you are encountering this problem, try connecting your cable to the player's headphone jack instead. Since the strength of the headphone signal is easily adjustable, you can then reduce the signal level sent to the PC. On most players, this means using the same shared line out/headphones out socket/jack, but choosing the headphones out option in the player's "Sound Out" Preferences menu.

If you have sound card which has digital outputs, connect from digital out of the MiniDisc player to the S/PDIF input of the sound card.

Links

>  Forward to: How to set up Audacity

|< Tutorial - Copying tapes, LPs or MiniDiscs to CD

Views
Useful External Links