Need help... Decibel Levels

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Rockstar Vatican Assassin
Member Since: Mar 20, 2009

I'm sorta new to the home recording arena and have read so many articles from so many sources, I'm about sick of recording before I've even dived in. Here's the situation and what I'm trying to understand.

I'm recording through a Delta 1010 breakout box, which comes with a software based input console/mixer. In attempting to record really brutal death metal guitars (using SM57s), I'm finding the tracks muddy and the waveforms very "narrow." Now, I know I can cleanup the muddiness by using other mic'ing techniques as well as using condenser mics, but what I'm really after is "what decibel level to record at."

I usually try to obtain a decibel level of about -10 to -12 decibels, but the tracks are so thin after being recorded, I have to add a sh**-ton of software gain, which ultimately introduces noise.

Should gain/decibels be controlled by the software or the Amp? In other words, in order to obtain a -6 to -10 decibel perfect waveform (like you see in the header of this website), should I set the software gain to -20 and control the rest of the gain by bringing the Amp up.... or set the gain in the software to -10 and then bring down the amp's gain until -10 is obtained? The tracks I've recorded so far look like bricks standing up, side by side. There's no fluctuation in the waveform as though someone took a lawnmower and shaved the peaks and valleys. Yet... I'm nowhere close to clipping. Any ideas? And thanks for reading!!!

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I am not a crook's head
Member
Since: Mar 14, 2003

Mar 20, 2009 01:46 pm

What amp are you using? What are your gain and EQ settings like on your amp?

Usually I can bet money that beginners trying to record heavy guitars are using too much distortion. Distorted guitars are compressed by nature and therefore don't have much dynamic range. So they'll usually come out looking like what you're describing, a featureless brick of a waveform.

Source material volume shouldn't matter a whole lot. That's what preamps are for, to amplify the microphone's signal strength to line level. Peaking at -20dB on your interface's inputs shouldn't be a bad thing.

Your guitars probably sound thin due to too much distortion and mic placement. That's a pretty safe bet for people recording heavy guitars at first.

Rockstar Vatican Assassin
Member
Since: Mar 20, 2009

Mar 20, 2009 02:43 pm

Thanks for the reply...

I don't know the exact model numbers, but one amp is a Johnson half-stack with a lot of low end whilst the other is a Laney head on a Krank cabinet with more high end. The sound differences are like night and day, which is also a thorn in my side, sort of speak. When I pan R and L for the guitars, you have one ear filled with low end and the other filled with squealing high end. So now I'm having to EQ (in a sense) using mic placement rather than just sticking the SM57 right up against the grill on both. As far as EQ on the amps... I have no idea. But based on what info I've provided, you got a suggested starting point? Like.... take the mids and lows out of the Johnson and add more low on the Laney? Or maybe, just add more low end on the Laney? I suppose only screwing around will get me the answer I'm looking for. Pain in the nads!!! I'm just a drummer!!!

MASSIVE Mastering, LLC
Member
Since: Aug 05, 2008

Mar 21, 2009 01:02 am

Quote:
I usually try to obtain a decibel level of about -10 to -12 decibels, but the tracks are so thin after being recorded, I have to add a sh**-ton of software gain, which ultimately introduces noise.

-12 is actually a little hot for electric guitars... -18dBFS or so is probably where your interface is calibrated to. Although -12dBFS isn't "crazy" hot, but I'd still back down quite a bit.

Quote:
n other words, in order to obtain a -6 to -10 decibel perfect waveform (like you see in the header of this website),

The waveform on the title of this page (at least the one I'm looking at) is clipped.

In any case - (A) You shouldn't be "looking" at sound. You should be getting a decent level around or under 0dBVU (which would equate to around -18dBFS digitally, again, depending on where your converters are calibrated to line level) and go. (B) 12dB of gain digitally is nothing. And it doesn't add any noise. Digital has no inherent noise.

If the sounds aren't what you're looking for, look at the core sound. If they're "muddy" it's not your recording levels (unless you're too hot, which could have a tendency to make them muddy, but also strident in the top end due to overdriving the input chain).

I am not a crook's head
Member
Since: Mar 14, 2003

Mar 21, 2009 01:25 pm

Remember that you don't HAVE to pan the guitars really wide in the stereo field. Maybe panning them closer to center will help balance your mix.

And explain to your guitarists that what sounds good to your ears in a room usually isn't the same as what sounds good to a microphone up against the grille. See if you can convince them to use guitar tones that benefit the recording and not just what they're used to using on stage or in their bedrooms.

Czar of Midi
Administrator
Since: Apr 04, 2002

Mar 21, 2009 06:56 pm

Yep, all of the above is more then true. Especially the distortion level and amps volume level. Odds are really good that is the two main causes of the problem your having.

Mic placement is also crucial as well. With a 57 you really want to get it out near the edge of the speaker near its mounting ring and point it towards the center if using extreme distortion. That is even what I do for clean guitars as well. That will capture a bit more of the tone of the speaker without slamming the diaphragm of the mic, which in turn can cause the distortion to sound even more distorted.

I would suggest bringing the level of the distortion down as well as the level of the amp itself and then let you pre amp and inputs of the 1010 bring it up to a recordable level.

You can experiment with mic placement and level's a bit until you find what works best. But in all honestly, recording with less distortion and volume, then recording a second track or layer will give you a much better sound to work with in the end.

Rockstar Vatican Assassin
Member
Since: Mar 20, 2009

Mar 22, 2009 06:45 pm

I think what's confusing me is that the breakout box has 2 inputs that have adjustable gain and input Monitor-level sliders (digital). The other 6 inputs are just analog (not much adjusting). If I require phantom power, I have to change the inputs from "line" to "mic" and select "use phantom power." The Shure SM57 mics don't require phantom, but I've still kept the inputs with the "mic" setting and the phantom power turned off. Should I just keep the inputs as analog/Line In for recording guitars? Perhaps that's what I'm doing wrong!!!!

For the curious.. here's the most recent attempt (note the muddiness).

www.cynonyte.com/audio/Cy..._The_Sun_v2.mp3

Czar of Midi
Administrator
Since: Apr 04, 2002

Mar 22, 2009 08:41 pm

Well you still want to use the mic input set as mic input. But I can tell now from listening to the recording that the guitar on the right is slamming the 57 pretty hard. Also it isn't placed properly in front of the speaker and isn't catching a good tone. The amp might also be set with way too much bottom end on it. Even though in the room it may not sound like it, the mic is hearing it. and so am I listening to it now.

Also the advice given to you about panning them that hard is correct. That is really mucking things up badly with the guitar's panned hard left and right like that. If you brought them more toward the center and blended them together a little bit you might find a happy medium with the sounds from each track.

Rockstar Vatican Assassin
Member
Since: Mar 20, 2009

Mar 23, 2009 08:03 am

OK... I'll do some experimenting this weekend. The guitarist will be excited to know we're doing it over again!!!

Last question: As far as the mic placement is concerned. If I line up the mic on the speaker edge and angle it towards the center, is the mic angled towards or away from the other speaker in the cabinet? So, for example, on a 4 speaker cab (using my half-@$$ drawing below), which edge should I be mic'ing.

Speaker 1 Speaker 2
outside1 O inside1 -- inside2 O outside2
outside3 O inside3 -- inside4 O outside4
Speaker 3 Speaker 4

My gut is telling me "inside1" or "inside2;" it's higher off the floor and away from picking up the other speaker (respectively). Yes?

Czar of Midi
Administrator
Since: Apr 04, 2002

Mar 23, 2009 09:33 pm

It doesn't really matter. I generally set it near the outer rim near the cab edge and point it toward the center of the speaker I'm over. It can be a bit in from the edge of the speaker ring. But going from the inside as well will work.

Have a look here at how this set up is. They are pointing toward the center of the cone from the inside edge of the speaker on the 4 x 12 cab.

www.homerecordingconnecti...tory&id=140

By the way dB, that was the number one resutl from goggling the phrase Micing a guitar cab.

Rockstar Vatican Assassin
Member
Since: Mar 20, 2009

Mar 24, 2009 08:07 am

Noize2u...

I actually read this article in the past doing one of my various Google searches and reminds me of why I asked my question in the first place. According to this article:

Quote:
Once it is plugged in at both ends (Mic and Channel Strip), then turn on the Phantom Power, wait about 10 seconds for it to level out. Bring the channel fader up to Unity (0dB) and set all the EQ's flat. Start off with the gain all the way down. Get a friend, your sessionist or anyone else to play the guitar while you adjust the gain trim - make sure that the signal does not peak and averages around 0dB on the mixer (Note, we are only dealing with the MIXER here, not the recording medium yet!).

This article assumes you're working with a hardware mixer but, regardless, my software control center has the same setup (i.e.. a gain dial and faders). The way I'm reading this is that the guitar amp is booming loud and the faders are set to 0dB.... right? Then, adjust the gain UP to maintain a 0dB signal. This seems to imply that despite the amp being loud as all, you'll still need to adjust the mic gain to maintain 0dB.

I'm finding that the amps are plenty loud and forces me to drop the faders to like -40dB at the mixer. But the distortion at that volume is "cropping" the peaks and valleys on the waveform (which creates muddy sound, right?). So to create a natural curvy/clear sounding waveform, I'm pre-setting my faders to -10dB and having the guitar players turn down their amps until the input monitors are showing -10dBs, respectively. That, however, is creating a really narrow, almost volumeless recording (i.e.. the waveform is curvy, but the recorded sound needs to be play'd back at like +1.6 dB in the mix. And that is what brings me back to my original question. What piece of hardware dictates the recording's dB level?

If the amp is pushing +20dB while the faders are set at 0dB, do I drop the faders to -40dB to compensate? OR..... While the faders are set to 0dB, do I turn down the guitar amps until -18dBFS is being displayed by the input monitors?

Sorry for dragging this out.... I'm just really wanting to understand which practice is the "best" practice. I have a hunch, based on what folks have posted on this thread, that dropping the faders to -40dB is the correct action... but to cleanup the cropping of the waveforms, I need to EQ the amps at the "head" so there's less crunch/compression going to the mics (Tadpui's advice).

MASSIVE Mastering, LLC
Member
Since: Aug 05, 2008

Mar 24, 2009 11:13 am

That isn't assuming you have a hardware mixer - It *is* assuming you have a hardware preamp (which you do). You need to set the preamp level to get your signal strength - Anything done in software (attenuation in this case) is *post* conversion and far too late to help.

Okay - Re-read it. It does mention a mixer. But it doesn't matter - They're only dealing with a single preamp, same as you in this case.

If you've recorded too hot, you've already overdriven the preamp and in this case, it sounds like you've rather severely clipped the converter.

With the software (actually, with EVERYTHING) at unity, set your pre-gain (preamp level, head amp, whatever it's called on your preamp) to get a signal floating around -18dBFS or so (which will give you a signal around 0dBVU, which is where everything is made to run).

You shouldn't need any EQ at the head amp. If you do, tailor the core sound first - tweak the mic placement second - do anything you possibly can to avoid using EQ at the input. Using EQ at the digital level is going to be the same thing (too late - it's already digitized).



EDIT:


Oh geez, the D1010... If you're using the built-in preamps in the 1010, MAKE SURE that whatever you need to do to get them running at MIC LEVEL is done. I have no idea what that is in the case of the 1010 - But I understand that they're switchable between mic/line somewhere - A jumper perhaps...? You may need to pad the input 10 or 20dB on top of that if the preamps are too sensitive.

Or just get a decent external preamp and run with it.

Rockstar Vatican Assassin
Member
Since: Mar 20, 2009

Mar 24, 2009 01:15 pm

I think I'm not explaining my scenario correctly. Perhaps my usage of the word "volume" and EQ is a bit deceiving so I'll attempt to clarify.

I have a Shure SM57 mic placed on the grille of a VERY loud guitar cabinet. The TRS cable from the mic is going directly to a digital input in my breakout box (which has a preamp). My input monitor (1010 software) is showing nothing but red on the indicators during guitar playing. Obviously I have to reduce something to prevent clipping.

At this point.. I have two options. Tell the guitarist to turn his amp down (which affects the overall sound/crunch of the guitar output).... or drop the input faders in the software down to about -20dB to steer clear of the red zone?

And the problem. Choosing to drop the faders down to -20dB, I have recorded a sound bit that looks like a "flatline" in Acid Pro 6. The drums / bass /vocals all have very high peaks and valleys (dynamic) but the guitar track looks like a waveform that was cut by a lawnmower on both ends. It looks like a giant stretched solid rectangle with no fluctuations (requires mega zoom on the track to see the peaks). At the same time, the track is muddy (which could be related to mic'ing as discussed already).

Now I know I could "Normalize" the track during mixing to make it appear as thick as the other tracks plus boost the volume, but this introduces noise. I could also use a compressor with a bit of "gain" which will certainly do the trick. Alternatively I could also use simple volume/gain plugins to give the track an overall boost.

But my question is.... during recording:

Should I have turned down the guitarist's amp and kept my faders (software) at 0dB so that I get a nice thick waveform? My software's digi gain spans between -60dB to +15dB (0.5dB per step) on input channels 1/2.

Or should I have dropped the faders to -20dB and kept the guitar amp as loud as necessary to sound killer knowing that the post-recorded waveform is going to look irregular compared to all the other instruments?

Or.. should I have done a bit of both? Where should I concentrate the majority of "volume" related issues. At the Guitar Amp itself.... or at the Input Faders? I suppose with enough practice, I'm eventually going to find my answer!!!! =)

Thanks, everyone, for the input so far.....


I am not a crook's head
Member
Since: Mar 14, 2003

Mar 24, 2009 01:32 pm

I think that your waveform looks like a flatline because you're still clipping your preamp before the signal even gets converted into digital and hits your Delta's control panel.

A few things you can try without altering the volume of the amp:
- turn down the preamp, if that's possible on the 1010
- use a pad inline with your mic to take it down -10dB or so
- find a different preamp and feed it into a line input on your 1010. this at least allows you to have a gain knob to use for the preamp itself. If you have a mixer or a stand-alone preamp, use that.

I find that my SM57 records pretty hot as well. I used it on a snare drum and even at the lowest preamp gain setting, it would clip on every hard snare hit. We just backed the mic off the snare a bit, but that's not an ideal solution.

I think that a less sensitive mic, a less sensitive preamp, using an inline pad, adjusting mic position or adjusting the amp's volume are your only choices. Adjustments to the volume knob are free :)

But I know what you mean that your guitarist has to have the volume at a certain spot to get the tone he's after. Sounds like he needs to use a power attenuator and save everybody's ears (If he uses a tube amp. If he uses a solid-state amp, then turn it down!).

Czar of Midi
Administrator
Since: Apr 04, 2002

Mar 24, 2009 06:05 pm

I think we just covered this in another thread as well but here goes.

If you are recording distorted guitars, turn the amp and the distortion down!

I know the article makes it sound as though the amp is cranked to 11. But that was not the intended statement.

To get a clear track that will have a life to it you need to record the guitar's turned down a bit. What might sound good live or right in the room, does not sound good to the mic itself. And will not sound the same on the track.

Rockstar Vatican Assassin
Member
Since: Mar 20, 2009

Mar 25, 2009 08:23 am

Alrighty.... I know I'm beating a dead horse here, but figured a few pictures would tell the tale of my woes!!! What I'm trying to display is the huge contrast between two guitar amps recorded the exact same way: Same spot in the room; same dB levels (-10dB); same mic placement (center against grille). Crazy!!

This first image displays the differences between the two recorded guitar tracks. As you'll see, one guitar (green track) is shaved, narrow, and sounds way too high pitched while the other track (blue) is a more dynamic/fuller track, but garbled and muddy (though not clipping).


http://www.rhythmandbrews.net/images/cynonyte/waveform-differences_1.jpg



This second image is closer look at the green track (Laney Head, KranK cabinet).


http://www.rhythmandbrews.net/images/cynonyte/waveform-zoomout_1.jpg



And the third image is a zoom of the blue track (Johnson Half stack). Note the flattened peaks on the waveform. Something definitely wrong!!!


http://www.rhythmandbrews.net/images/cynonyte/waveform-zoomin_1.jpg



The Fader w/ Digi Gain console. While this pic shows it being pre-set to about -5dB, I usually have it set to -10dB during recording. The article mentioned above seems to indicate I should have this @ 0dB during recording.


http://www.rhythmandbrews.net/images/cynonyte/1010Fader.jpg





Administrator
Since: Apr 03, 2002

Mar 25, 2009 08:24 am

don't put the [img] things around them, just the URL...

Rockstar Vatican Assassin
Member
Since: Mar 20, 2009

Mar 25, 2009 08:28 am

Noted!!!

I am not a crook's head
Member
Since: Mar 14, 2003

Mar 25, 2009 08:51 am

Like we've mentioned a few times now, I still think you're clipping your preamp.

> > > Need help... Decibel Levels

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