Skip to main content

So.. I'm recording some guitar and one side of the channel clips or the waveform periodically looks like a solid block, but when the volume is lowered or attenuated in any way, the pedal being used by the guitar totally loses it's 'mojo'. WTF?

Any ideas on how to cure clipping in a situation like this? I've tried several different things and nothing has helped yet..

Comments

Boswell Sun, 06/29/2014 - 11:22

Tell us a bit more - type of guitar, the pedal and pre-amp (or interface) used, and exactly how you have them connected, e.g. type of cable and which input you plug into.

What do you mean by "one side of the channel"? Also, when you talk about lowering the volume or attenuating, which control are you using for this?

Keri Sun, 06/29/2014 - 11:39

Boswell, post: 416518, member: 29034 wrote: Tell us a bit more - type of guitar, the pedal and pre-amp (or interface) used, and exactly how you have them connected, e.g. type of cable and which input you plug into.

What do you mean by "one side of the channel"? Also, when you talk about lowering the volume or attenuating, which control are you using for this?

How is the type of guitar or cable relevant? That makes no sense, since it doesn't even remotely pertain to my question..

Keri Sun, 06/29/2014 - 12:53

Here's my chain:

Guitar -> pedal -> amp -> DI -> mixer -> converters -> DAW

My converters do not clip, but the mixer does. If I try to lower the
volume on the pedal, amp, DI or mixer, the pedal loses it's 'mojo'.
The waveform on one side of the stereo channel being recorded into
the DAW is periodically clipped on one side (left), but again, if I try to
alter the volume or panning on it in any way, the pedal loses it's 'mojo'.

Keri Sun, 06/29/2014 - 17:06

Kurt Foster, post: 416527, member: 7836 wrote: i'm guessing the "mojo" you are referring to is coming from your monitors being driven into clipping. try micing the amp instead of using a di box.

Well, after I record something with the left side clipping, the 'mojo' from the pedal remains, so I know it's not from the monitors. It's just when I try to alter or attenuate the volume in any way. It seems there's a precise frequency involved. As for micing, there actually is a mic involved, but it's a separate part of the guitar mix. This DI'd part of the mix deals with the 'direct to DAW' end of it. I should also note that the periodic clipping doesn't sound awful, but I'd still like to get rid of it somehow. Oh yeah, I did think about compression too.. nah.

Keri Sun, 06/29/2014 - 18:12

Josh Conley, post: 416533, member: 47953 wrote: you are recording a mono signal into a stereo channel?
perhaps start looking there.
the rest of the mojo and attenuation bits are nonsense to me.

Interesting.. well that would be a dual pair going into left/right in on my mixer and then the outs are mains out to a left/right stereo pair on the converters. I didn't expect anyone to really get the "mojo" end of it. What I mean by that is - it's what the pedal is doing and if any volume levels or settings on anything else or the mixer is touched, the frequency is so precise, it lose that certain "mojo". So what I'm trying to do is stop the clipping on one side of the stereo pair without losing my grip on reality.

Josh Conley Sun, 06/29/2014 - 18:54

lets back up so we can gauge your experience level.
do you understand the difference between mono & stereo?
how about balanced and unbalanced cables?

lets start at inception.
guitar to DI via a cable with one black line on it or two?
DI to mixer, same question.
mixer to interface, same question.
boswell was attempting to ask you about cable selection before you dismissed him because, yes, its important!

how are you getting a two signal paths from one signal?
a guitar has one output jack, it is a mono instrument, just like a microphone.
where and when does this split happen?

pcrecord Mon, 06/30/2014 - 06:46

Keri, post: 416520, member: 36349 wrote: How is the type of guitar or cable relevant? That makes no sense, since it doesn't even remotely pertain to my question..

Types of cables may change a lot it you're not respecting every impendance of input/outputs in your signal chain.
Ex: if you use a 1/4in to XLR cable between your pedal board and the mixer. You are in fact sending a line level signal to a mic level input and can damage the mixer.
I'm not saying that's what you are doing, just that cabling a signal path needs a little knowledge to avoid problems.

Now the mojo! As I understand, it may come from the fact that you are overdriving the preamp of your mixer. All preamps brake in distortion when you send a signal that is too hot or if you push the gain too hi. Some preamps have a nice and pleasing distortion and others sound like crap. Also, some preamps are made to be overdriven and others are not. For exemple, a UA LA-610 sound really good when you push it hard. If I have to use an amp simulator, I may plug the guitar in that preamp, make it distort just a bit and then send it to the computer to be processed.

So your mojo is probably coming from some part of your signal chain that is overdrived. if you lower the input the sound you like isn't there anymore. What can you do? Well, if it's the mixer as I think, those preamps are not very robust as other outboard preamps. You may in fact damage your mixer in the long run (without saying that you are killing all dynamics of your performance). You should find another way to get a good sound.

Kurt was right, if your sound is good in front of the amp, it is because the speaker is producing the sound a certain way. If you use a DI, you are bypassing the goodness of the speaker. (unless you are using a Line6 amp which have a Amp simulator prossessor in it) In any case, you are better off with a mic in front of the amp.

anonymous Mon, 06/30/2014 - 09:06

Okay, so, You're saying that you are plugging your guitar into a pedal you like, and, getting a tone you really like... but the problem is that you are clipping the pre/audio I/O input to your DAW, right?
And the track is showing you that you are clipping because of the waveform on your track...

If that's the case, you don't need to lower the input or output of the volume on the pedal, if that's the tone you dig... just turn down the input channel of your I/O into the DAW. It shouldn't effect the tone at all, because the attenuation is being done after the pedal.

It's basic gain structure.

Unless I'm missing something here...

Are you're saying that you like the sound of the I/O preamp clipping?...

Keri Mon, 06/30/2014 - 21:45

DonnyThompson, post: 416560, member: 46114 wrote:
If that's the case, you don't need to lower the input or output of the volume on the pedal, if that's the tone you dig... just turn down the input channel of your I/O into the DAW. It shouldn't effect the tone at all, because the attenuation is being done after the pedal.
It's basic gain structure. Unless I'm missing something here...

Hmmm.. that's actually something I haven't looked into, since the input level on my converters are always set at +4dBu going into my DAW and I'm always only just concerned with the -10dBv output level or I usually just ignore the +4dBu input level. Thing is though, I have two other mono tracks for hard Left/Right panning and those volumes will also be effected. I'll have to look into this one. That's something I've probably been overlooking for quite some time, so thanks for that ! (y) Much appreciated..

DonnyThompson, post: 416560, member: 46114 wrote:
Are you're saying that you like the sound of the I/O preamp clipping?...

Yep, I actually don't have a problem with clipping in this instance. I can't even really notice it, since it doesn't even sound distorted, at all. The irony of it is though, it seems to actually be the source of the "mojo" I'm referring to. As I was saying before, although my mixer is before the converters, the converters don't even clip, but the mixer does! Inside the DAW recording software, only one side of the stereo channel waveform can be seen as periodically clipping. Is that nuts.. or wtf !?

DonnyThompson, post: 416560, member: 46114 wrote: -

pcrecord Tue, 07/01/2014 - 05:23

First, dbu and dbv are not the same unit of measure. Here's a convertion table : http://www.sengpielaudio.com/calculator-db-volt.htm
You should avoid using miss match db levels and impedance. If your mixer is rated -10dbu, you should change the settings on the converters to fit.

A good gain structure results of no peak in the mixer and no peak in the converters.
In your DAW, each instrument should peak around -16db to -12db and the sum of the mix (in the master bus) shouldn't peak higher than -6db. Also, there's no problem to record at even lower levels, specially if you are at 24bit. This will ensure the best sound quality and dynamic preservation.
Recording hot signal was very important with tapes because of the noise ratio but with todays digital converters you can record way lower levels

So it means you can create the sound you want with your guitar amp but when the signal hits the mixer, you should lower the gain of the mixer so the line doesn't peak and match the db levels of your converter to make sure the DAW capture -16 to -12db peaks.

If the mojo you like isn't there after these settings, add effects in your daw to get it back. (EQ, Compressor etc..)

kmetal Tue, 07/01/2014 - 10:01

If your not clipping at the conversion stage, I don't really see what the problem is, if it sounds good. You don't really in general want to be clipping in your daw meters, cuz that usually sounds unpleasant, and you'll want some headroom like PC described for mixng time when you you eq or compress or whatever.

Other than that, who really cares what's clipping if it sounds good, that's rock and roll. Gain staging is extremely important, but it's not a hard and fast rule, especially when talking about dag nasty sounds of a distorted electric guitar. When your talking pristine, and full rich, and reducing noise as much as possible, that's when it comes into play in a much more technical sense.

Dunno what mixer and interface your using, but if your clipping your interface input w the gain knob all the way down, try engaging a the pad. Again all that matters in general is the daw has plenty of room, to cleanly capture a nasty signal. If your seeing squared off waveforms, taking up the whole width of the track lane/region, your likely hitting 0dbfs, or the clipping point of a converter. If you aren't seeing the red in the DAW but still seeing squaring, that's just the result of analog stuff clipping, which is what your liking the sound of.

Bottom line, if your liking the sound, don't mess w the pedals or mixer, it's a simple task of setting the gain properly on the interface so it doesn't do the nasty digital distortion thing. And if you are clipping digitally, and that's part of what you like, and can't get it from plug-inslike the decapitator from sound toys, or other harmonic distortion plugins, or you just like it. There's no problem at all. But my gut is telling me your just a little unfamiliar w setting the level on your interface. Hope this helps.

RemyRAD Sat, 07/05/2014 - 10:04

Most anything that has a rated +4 output, typically has Headroom, to +18 DB output to, +24, +28, even, +30. Which when you plug any of that into inputs designed for consumer level devices at -10, I don't care if it's db M, U, V, those inputs are going to be swamped, saturated, overloaded, by professional output devices. So maybe you're just missing the overload input Mojo, when you back the signal down? We get similar manipulation of our audio, doing the same with those classic pieces by API & Neve.

Unfortunately, if you try to record that, that way, you'll get useless dreck. It won't have any Mojo. It won't have anywhere to go when it's a brick. So we want to record that Mojo sound rather than just obtaining that Mojo sound. But to do that effectively, gain staging has to be done exactly right, the wrong way. Or exactly wrong, the right way. Otherwise you don't get what you want.

The key here is to figure out what Mojo you like? How to contain that Mojo. How to pass that Mojo on to the next stage. And capture that Mojo. This might require external passive volume controls or fixed pads. Which will be necessary for the gain stage matching. Because we only want to overload what we want to overload and not what we don't want to overload. I know this explanation can be a bit overwhelming on the overload. Nevertheless, you want to overload not overlord.

Obviously as a few others have mentioned, your understanding is a bit, what we would call, limited. Which has nothing to do with dynamic range processing.

Now... when you record a guitar, you've got options. As indicated, you're using a microphone on an amplifier. That's good. More than one different type? That's good. Both laid down on separate tracks. That's good. Also a DI. Going to a separate input and to a separate track. That's good.

So why does anything need to go into your mixer? Because you want to overload something but pass out, normal operating levels. But if you're getting your Mojo from the wrong gain stage? You're going to have to figure out a workaround. Or help us to help you? Trying to put things in the technical terminology that you don't understand, only confuses us. You're not impressing us with what you don't understand by using terminology you know nothing about. There are no audio specifications that indicate percentile of Mojo. Or how you are supposed to shoot and kill it for dinner? When you say Mojo it just makes me think of all that I missed doing yesterday during the July 4 celebration. My last chance to celebrate it on the Mall, in Washington DC, until I move away forever, Tuesday. And I used to work that for nearly 20 years. Now just a fleeting memory I can't get back. Maybe the same with your Mojo? Then ya thus have to make good recordings instead. So sorry...

Mojo doesn't just happen. Though sometimes it does.
Mx. Remy Ann David