Eq And Other Questions

[Donna]

Hey all~

I have various beginner questions in preparation to engineering again. It seems to me it may be becauese my equipment is so scaled down that I'm not understanding some things, but who knows.

From Page 3 of the Songstuff EQ article re: using EQ to rectify common problems:

Identifying a frequency

Firstly, be careful! Turn down the volume before you start so that the sound coming from your monitors is pretty quiet. If you don't you run the risk of damaging both your ears and your monitors. Set the Q to a very narrow bandwidth and set the boost to between + 6dB and +12dB. Using the EQ frequency control to sweep the frequency range in question. When you get to the correct frequency it will be obvious because of the jump in volume. Once you have identified the problem frequency change the boost to a cut of -6dB. Set the overall volume back to normal listening.

1. How does one judge the db's of the boost or cut? Does this mean the black/red UV meters?

2. Just to understand, is setting the Q comparable to manipulating one's own synthesizers sounds (ie making their own)? AFAIKI my unit has a fixed Q.

Thanks!

Edited October 1, 2006 by Donna

[Donna]

Question 3 on musical note frequencies:

Note - c0 Frequency (Hz) - 16.35

John, does the zero mean the lowest C note on the piano...the notes with zero's next to them'd be the lowest octave, ascending accordingly?

t/y

[Nick]

Question 3 on musical note frequencies:

John, does the zero mean the lowest C note on the piano...the notes with zero's next to them'd be the lowest octave, ascending accordingly?

t/y

It sure does - see note frequencies

Edited October 2, 2006 by Nick

[Nick]

From Page 3 of the Songstuff EQ article re: using EQ to rectify common problems:

1. How does one judge the db's of the boost or cut? Does this mean the black/red UV meters?

Not to be flippant, but with your ears! Once you can identify the frequency that needs cutting then experiment. If it still sounds too much cut it a bit more, if you overdo it boost it back up a bit.

2. Just to understand, is setting the Q comparable to manipulating one's own synthesizers sounds (ie making their own)? AFAIKI my unit has a fixed Q.

There is an explanation of Q here - in a nutshell it is a measure of how much frequency around the centre frequency you are looking to affect with the equalisation (Or that's how I understand it!). Broadly higher Q numbers cover narrower frequency ranges and lower numbers apply the change across a wider range of notes/frequencies. Not sure how that relates to what you asked about making synthesiser sounds

[Donna]

Hey Nick,

Thanks. That Q link is dense and I'll refer back to it.

What I meant was, it sounds like if one has the equipmnent, thtat they can set, alter or fix the Q...which the only thing come to mind comparable was manipulating synth pathch or however it's termed, to make one's own sounds, not having to rely on presets.

"Use your ears"...lol, isn't that a given? I'm trying to figure out the terminology/its application.

So does this mean, if there's nothing "on" the mixer to denote db's (as there is with eq, 2.8k, 8k, etc;) then knowing db's is like common knowledge, like knowing the dif between red-violet and violet? One doesn't nec. need a reference chart?

I wanted to know exactly how the db's are measured in order to try the "identifying a frequency" experiment verbatim as written. So I hear exactly what they're talking about (I'm sure there are differences dep. on equipment, what instrument used, all that). Which will help me figure out other terminology, at least in my head.

Edited October 2, 2006 by Donna

[Prometheus]

So does this mean, if there's nothing "on" the mixer to denote db's (as there is with eq, 2.8k, 8k, etc;) then knowing db's is like common knowledge, like knowing the dif between red-violet and violet? One doesn't nec. need a reference chart?

When you're starting out, a reference chart can be useful as a rough rule of thumb, but realisitically the only way is practice practice and more practice... The figures given below are pretty reasonable ball park figures to start experimenting with...

Muddy - Cut around 200-250Hz

Boxy - Cut around 450Hz

Harsh - Cut around 1-2 KHz

For punch on a bass, boost at 110Hz, for warmth boost at 60Hz and cut around 250Khz.

For extra sizzle on a mix, boost 10KHz slightly, for extra gloss, boost around 15KHz...

It's also a question of understanding the room that you record in of course. A room 3 meters long with parallel walls would create standing waves at 55Hz and 110Hz (where half a wavelength or a whole wavelength fit perfectly across the space) and then a series of harmonics at integer multiples of the fundamental frequencies 220Hz, 440Hz, 880Hz etc... This would tend to cause problems with the low midrange and bass frequencies that would have to be fixed by subtractive EQ... This is the area that inexperienced engineers tend to have problems, leaving too much midrange on their products. 90% of the problems that occur in a mix will be below 1000Hz (1KHz)

[Donna]

I knew you would show up, "Pal O' Mine".

Did you know there is a song by the title of "O Pal O' Mine, Where Are You?" or something similar. I bought the sheet music for it once at a garage sale.

OK, got it, check. Engineering sound is math! Thanks, Prometheus. I'll be making a chart soon, a visual one based on the EQ article, adding also whatever y'all have set out in this rec forum.

Um...so is db's the same as volume? (ie: cut/boost)

(*pushing her luck?*)

[Prometheus]

I knew you would show up, "Pal O' Mine".

Did you know there is a song by the title of "O Pal O' Mine, Where Are You?" or something similar. I bought the sheet music for it once at a garage sale.

OK, got it, check. Engineering sound is math! Thanks, Prometheus. I'll be making a chart soon, a visual one based on the EQ article, adding also whatever y'all have set out in this rec forum.

Um...so is db's the same as volume? (ie: cut/boost)

(*pushing her luck?*)

Hi Donna,

The dB scale is a measure of the difference in volume between two sounds where the difference in power is equal to 10 Log (power1 / power2), so a 60 decibel difference in Sound Pressure Level would make one sound a million times more powerful than the other...

What I forgot to mention, if you're looking at where the most basic room problems will occur, the velocity of sound is equal to it's wavelength (lambda) multiplied by it's frequency, so v=lambda by frequency... By using algebra to change the function of the equation, then frequency = velocity (at sea level 330 meters or 1000 feet per second) divided by lambda...

So, if your room is three meters wide, then 330 / 3 = 110 hertz... Since standing waves will occur also where half a wavlength fits across a space, there could also be problems at 55 hertz...

The way to solve these problems would be either to use a Helmholtz Rezonator to absorb excess low frequency, which you would need a joiner to build to spec for you, or you could try putting pads on the walls to try to eliminate the parallel surfaces. Even a matress or such like attached to the back wall can help here, like the one behind me in my avatar... I tend to accept that the room my studio is in will never be perfect and use EQ to mitigate the worst of the problems, because as you've probably noticed by now, you could easily get lost up your own arse for the rest of your life trying to create a perfect room...

Edited October 4, 2006 by Prometheus

[Donna]

Prometheus, how did you know I've been musing about the rec. room? I hadn't even mentioned that!

Coincidently I'd just read one of your articles here the past few days and saw the above formula therein.

Time to think again - thanks for all your help.

[Donna]

Any opinions/experince on something a guitarist/owner guitar shop said:

1) He never goes direct with acoustic guitar and prfers to use a "stereo" omnidirectional (I don't think that was the term, tho) mic *aimed at the soundhole, not the neck*. Said the sweet spot is by soundhole.

2) Also said the large body acoustics which sound great and can compete unplugged (as it were) in acoustic gigs such as folk thing even gospel (choir I'm sure he meant) end up reaping phase cancellation in recordings...that a smaller body'd instrument will cut thru in the mix.

Hey: I had a great time tonite visiting drum shop, repair shop and guitar store, played 4 acoustics, def. leaning away from the Cort, anybody ever hear of Canadian Seagull I think it's called?

The funnest parts besides trying stuff out is knowing enough to talk about recording with both repair and guitar store guys. That is due to this little forum! The drums I already know about, and have my eye on a GREAT set of high-hats which are more expensive than the seagul and martin axes I played!

Hey! My AKG's (headphones) are in the AKG hospital, finally, woo-hoo, gimme some brewski's

What a nice thing to hear that the repair is doable and cost effective, but also that due to them being such an OLD model, the repair god there said they're much stronger and better made.

Now I have been without my AKG's since they went kaput about 6 babies ago. So it'll be like having brand new monitiors.

Edited October 10, 2006 by Donna

[Nick]

Any opinions/experince on something a guitarist/owner guitar shop said:

1) He never goes direct with acoustic guitar and prfers to use a "stereo" omnidirectional (I don't think that was the term, tho) mic *aimed at the soundhole, not the neck*. Said the sweet spot is by soundhole.

I'm sure Prometheus will know much better about this but for what it's worth...

I really don't like the sound of a direct output from an acoustic guitar and much prefer either one or two mics. Depending on how I'm playing the guitar (ie fingerpicking or strumming) I will probably stand a foot or more away and if it's two mics point one at about the twelfth fret and one about the bridge. If you point it at the soundhole you will tend to get too boomy a sound.

Alastair always used to plug his in and play it direct and I experimented with that early on but don't think it sounds much like an acoustic.

I think on stage that people will often do a combination of direct and also mic - I watched Richard Thompson playing an acoustic on a couple of YouTube videos last night and he was using that sort of set up and it sounded like an acoustic!

I think there are various configurations of mics like in an x shape, or over the shoulder on the basis it should then something like your ears hear it but I have got (given the limitations of the mics I use and the rest of the equipment) a sound that I can live with for what I want to do.

I hopefully will be putting up a song I have written in the next few days which just has an acoustic guitar backing so you will be able to see what you think!

2) Also said the large body acoustics which sound great and can compete unplugged (as it were) in acoustic gigs such as folk thing even gospel (choir I'm sure he meant) end up reaping phase cancellation in recordings...that a smaller body'd instrument will cut thru in the mix.

I think that is one of the reasons that they use a special guitar sometimes in recordings (especially country) where they double the guitar sound with a guitar that has the E A D tuned an octave high - never tried it but I believe it is a commonly used trick as it moves the bottom range away from conflicts with instruments/voices and aids clarity

Hey: I had a great time tonite visiting drum shop, repair shop and guitar store, played 4 acoustics, def. leaning away from the Cort, anybody ever hear of Canadian Seagull I think it's called?

There is a folk forum I use a lot at Mudcat and there are various discussions in the forum there about the merits of Seagull guitars. There is a guy called Clinton Hammond who plays a fair amount in Canada who swears by them.

Now I have been without my AKG's since they went kaput about 6 babies ago. So it'll be like having brand new monitiors.

Monitoring through headphones - you'll get told off

[Prometheus]

I agree with Nick, if you place a mic too close to the sound hole on an acoustic guitar the resulting recording will be boomy...

A general rule of thumb is that the further away you place the mic from the guitar, the more room reflections you'll record... In a room with a nice sound, this makes the recording more natural sounding and may be a desirable way to record, however, in a room with problems, close miking the guitar with a cardioid mic will eliminate some of the room ambience and create a dryer sound. An artificial reverb can then be used to create a room sound to order... Usually what is required is a compromise between dry close miking and more natural sounding ambient miking, and using two mikes, one close and cardioid, and one more distant and possibly omni can be a good way to achieve this, and using compressors or fader movements to change the balance between the two.

If you have a room where you feel your guitar sounds great, then use it. After all, why simulate a room artificially when you already have one?

[Nightwolf]

what they said

[Prometheus]

Monitoring through headphones - you'll get told off

I just noticed this... Yeah, monitoring through a set of cans, no matter how high quality, is a stupendously bad idea... The spatial feel is totally distorted through cans and perception of the spectral domain (i.e. the EQ of the mix) cannot be trusted...

I would most definitely give any aspiring sound mixer the soviet to buy a set of monitors, even if they are pretty cheap ones... A pair of second hand Alesis Point Seven's like the ones I have, or something similar, shouldn't cost much more than a hundred dollars, and they are the most important mixing tool of all...

If you can't hear a mix accurately, you can't balance it accurately, and monitor speakers and microphones are the two things that cannot be re-created virtually on a computer...

[Donna]

Hey Nick - thanks for all the info and link.

I was surprised to hear this guy say the soundhole. The method you use of two mics and placement sounds familiar, I'd read that on Songstuff resource and had been experimenting but never micing "to" the soundhole since. Interesting you prefer not going direct and R. Thompson's onstage set up.

Well I'll keep body size and all in mind as the guitar search continues.

[Guest voclizr]

Lady D;

Re your EQ thing: If you're using your little cassette portastudio you're really not going to be able to get too fancy with equalization. I could be wrong, but the model you have probably doesn't even have a midrange at all, let alone a sweepable one. If you invested in an external stand alone EQ module, that's different, but on those little cassette jobs, EQ is just over glorified bass & treble controls. My Fostex didn't even have numbers on it! Now, if you went out and bought a stand alone module to patch through, that's a much different story, but still, it's good to learn these things. You never know when you might get the opportunity to use the knowledge,

Re use of headphones: You have to use them in certain situations, such as micing a guitar or cutting a vocal track, because depending where your monitors are, you might get feedback with an open mic close to monitors. If you're going direct on guitar it's OK, though.

I studied audio engineering in the 70s and the instructor said to ALWAYS mix through speakers, NOT HEADPHONES. Just yesterday I found out how true that advise is. I don't have field monitors so when I record I use headphones. I still don't have a stereo yet so I use them to play back (through the computer). On the 2090 (Zoom equipment) forum, the guys were telling me that on my new song, "Still In Love" the ride cymbal was a bit too hot in the mix, though it doesn't sound too hot in the headphones. Yesterday I took a CD of it down to my parents who have a fairly decent stereo and found out that the Zoom guys are right. The ride is a bit too loud. It's too late to do anything about it now because Bill did his tenor solo over an MP3 and as such, I can't break the tracks down anymore and I don't want to impose on Bill to do yet another take on the horn (he probably couldn't recapture it again anyway) so I'll just have to live with it! So use cans (when you have to to record), but NEVER mix with them! BTW, Songstuff people, I'm still waiting on your feedback on this song (see Demo Reviews). 'Nuff said!

I have AKGs too. 600 ohm K 240 Monitors. Very expensive, BUT WORTH IT! I've had them for quite awhile.

They're a favorite of the some of the pro studios.

Just my $.02.

John B.

[Guest voclizr]

"BTW, Songstuff people, I'm still waiting on your feedback on this song (see Demo Reviews). 'Nuff said! " Quote John Bowen.

Sorry Donna! I don't want to hijack your thread, but I should clarify the above. Waiting for reviews on the Omegaman mix! The other was reviewed! Now I'll get off my hi horse and let Donna HAVE HER THREAD BACK!

Thanks Donna, for being so gracious!

John B.

[Donna]

JB, fortunately my portastudio has a pretty good mixer, w/ sweepable eq, two tiers, one for htz and one for "k" (up to 8 k). It's a tascam 246. But it's worth thinking about a separate mixer.

JB just curious about the ride cymbal...had you listened to the mix on a deck(s) with speakers before you made it a master mix?

I guess that'd be sort of a monitors-once-removed, huh? That's where I'm at for the time being and looking forward to enlightenment in the future.

At any rate, the AKG's won't spill the sound which is a big problem with the tune I'm working on. It'll just be really nice to record with BOTH sides of the good headphones working.

[Guest voclizr]

Donna;

Sorry about that. I guess the Tascams were better than I thought they were, although I always knew they were better than the Fostex's.

Regarding your question about the ride cymbals: Negative. Headphones all the way.

John B.

[Donna]