Line In or Phono

[JTRS]

My mixer deck has a switch on each channel marked Line/Phono and on the back has 2x2 inputs for each channel, again marked Line and Channel.

Am I right in thinking that a Phono signal has already been pre-amped and is therefore louder/stronger than the Line signal?

If I plug in something like another CD player or a Karaoke player and the outputs are not marked to state whether it's a Line Out or a Phono out can I assume that if they are the standard colours (ie Red and White) and take an RCA plug that it is Phono and plug it in accordingly?

Finally, if there is ever a doubt about the signal output which is the safest option to plug it into on my mixer, should I use Line or Phono?

Any help or advice would really be appreciated

Thanks in advance

JTRS

[Jiggles]

Phono - Turntables
Line - CD players and such.

[Dynamic Entertainment]

Phono is only for turntables, everything else is line/cd as far as im aware.

[DeckstarDeluxe]

Line all the way

If you plug in a cd player into a phono then you'll get an awful loud sound coming through. This is because the output signal from a turntable is alot quieter than an cd player, ipod etc..

[Happy Jack]

JTRS, you pretty much have it. Make a note, though, that the red and white denote the left and right channel of a stereo send. It doesn't dictate whether it is 'line' or 'phono'.

As others have said, the cartridge (pickup) on your turntable headshell outputs a relatively weak electrical signal much like the same way a passive microphone - think SM58 - or an electric guitar.

Plug your turntable into the line input and your notice how quiet it is. Raising the master fader at this point not only amplifies this low level signal, but also the electronic / thermal noise that exists on every electrical circuit. You turn it up loud enough and you'll hear the hum / hiss!

You should aim for the highest possible signal to noise ratio for clean, undistorted audio and a better gain structure. Not so important on short, simple cable runs to and from a 2 channel mixer, but something to bear in mind if you use a bit of outboard / processing.

Plugging in line-level signals into the 'phono' is only going to damage the sensitive transistor circuitry that amplifies a low 'mic-level' signal into a 'line-level' one, and this is the 'awful (distorted) loud sound' deckstardeluxe is describing.

The Rane notes are an absolutely fantastic (free!) resource. Read up a little on gain structure, signal flow and dynamic range, as well as balanced / unbalanced connections. It helped me out!

http://www.rane.com/note135.html

:beer1: