Strange Wave Form

[ClarkJaman]

Hey Guys!

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This is an acoustic guitar recorded line in with the built in pickup. Why do the transients point upwards but not really down? It's not using the whole space. What does this mean?

[hueseph]

Someone will answer you. Just be patient. I don't know the answer to this. It may be a phase thing. It may be a view setting in Cubase. I don't know. I'm sure someone here will though. Boswell or dvdhawk. Some of these guys are very knowledgeable. I wish I could count myself among them but they are leagues beyond my ability.

[ClarkJaman]

Don't worry, I am patient.

[Laurend]

Recording an acoustic guitar output on a line input isn't satisfying from a technical point of view. A high impedance input (DI) would provide much better results.
The wave form is pointless. "Is you're sound OK?" is the only serious question.

[ClarkJaman]

I can't remember for sure, but I think I was using a DI box. This isn't about the quality though. I was just recording a scratch/guide track while I was tracking drums with a client. I am just curious what this means. And no, the sound was terrible, lol.

[DrGonz]

Take the track as an independent track in some editor (soundforge, wavelab or whatever...) and apply DC offset correction. What does the wave form look like after you run DC offset correction?

[thatjeffguy]

Ditto DrGonz's suggestion... looks like a DC offset issue. Most DAWs provide a "correct DC offset" function for this.

Jeff

[ClarkJaman]

I don't think it's a DC offset issue, because the wavefoarm is still centred on the 0dB mark. It just extends further up than down. I tried removing DC offset on my DAW and it didn't make a difference. :/

[Laurend]

It seems that the positive part of signal is more amplified than the other.
Does your guitar needs two batteries to power its preamp? A weak amplification related to an almost empty battery may explain this poor sound.

[Boswell]

One answer to the original question is that waveforms can look like that - it's not your eyes that respond to the sound. I'm assuming that the recorded sound is OK, and that you are tracking this down out of interest and not trying to diagnose a sonic problem.

Is this recorded from a magnetic pickup on the guitar rather than an internal guitar mic or an acoustic pickup? A magnetic pickup is a velocity transducer and captures a representation of the speed at which the string is moving and not the position of the string. Guitar strings move rapidly on the first release after the pick hits and then, depending on the players hand action, can damp relatively quickly, unless they are open (unstopped).

The first check here is to see what happens to the waveform on an up-pick rather than a down-pick. If the higher peaks of the waveform are now in the negative half, then there is the simple answer. If the waveform still looks similar, then make sure you are going directly from the guitar pickup into a pre-amp DI input and not through a pedal or some other effect unit. If the waveform still looks the same with a clean chain from pickup to DI, check that you do not have any compression or other amplitude-altering effect set in your DAW.