I have a couple of synths, but when I run the signal from the line level outputs (even with max volume) I find that the signal never reaches 0 decibels, even with max output.

This means I often have to turn the gain on the mixer up.

But isn't the point of a line leve output to avoid this ? I'm confused

Depends on the head room. Non-pro equipment can have a larger buffer than pro-audio gear, causing the level to drop by 7dB for example.

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Hey Cheggy, can you or some one explain this "headroom" concept to me ?

Is this because it's cheaper to produce, useful in some way or just to protect the speakers ?

One of my synths is a v-synth. For 2K, I would have thought that would be close to pro audio equipment

I would emagine that the V-Synth would be pro but your mixer or soundcard might be consumer. I don't know enough about it to comment any further sorry.

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1 out of every 4 people in this country are mentally disturbed. Look at your 3 closest friends. If they seem okay, then you're the one.