Bass/Treble Roll Off On Mics

[Derrick]

So with all the info I'm reading about recording, tell me if my thinking/thought process reguarding recording is correct...

For mikes with a "bass roll off" switch, if you are recording, say... acoustic guitar, some readings have suggested rolling off the bass by using the switch on the mic to cut some of the excess bass. Wouldn't it be better practice to record with the mic in it's normal switch positions and just cut bass later on in mixing so that you have the ability to change things then offering more flexability in mixing and your overall sound? I mean, you can't change a track once you've recorded it with a mic's treble or bass rolled off right?

[scarygroover]

that's pretty much what I do. I mean I'd hate to roll off something I wasn't sure about.

[eeldip]

yea, but... for some sources you just KNOW you are gonna have to roll of the bass anyway.

lots of bass roll offs on mics for example, just cut off 80hz and below. do you need 80hz and below for vocals.... hard to imagine. same for acoustic guitar.

this is especially useful if you only have limited access to eqing either through limited channels of eq or limited processing on a DAW.

plus, some mics have rather nice cuts... my md441 for example with the old M to S dial makes it very easy to tailor a roll off for individual sources.

[scarygroover]

yeah I guess you are right there. I'll have to try that on vocals and acoustic guitars.

[Bear]

I use the bass roll off on Acoutics and Vocals too. I've found they fit in the mix better than when I EQ afterwards (I also don't have a great EQ at my disposal, which certainly affects things). Especially when the song has a lot of instruments going at once, which I do often. But if I'm recording a song with just guitars and vocals, I leave the roll-offs alone.

[percussion boy]

my md441 for example with the old M to S dial makes it very easy to tailor a roll off for individual sources.

Say more? I've just been leaving mine in "M" (no rolloff).

Re original question, the cutoff point varies a lot from one mic to another. I never use the cutoff on my AKG 3000B for vocals -- too drastic; paperwork says it cuts at 6db/octave all the way up to 500 Hz.

[Derrick]

Hmm... I have two mics with bass roll off: a Sure SM-7 and a EV RE-15 (both over 20 years old). How will I want to experiment using them... on vocals and guitar when other are involved? Any other situations? Man, I've learned on this and other boards over the past month that there sure is alot more to pro recording then just having a good ear, decent equipment, and an open mind! However, I figured as much which is exactly what brought me here in the first place. I've already improved my sounds/teqhniques so much. Thanks all.

[dwelle]

i have an old sm7 that sees a fair amount of action for vocals. didn't used to, but now i almost always use that mic rolled off for that application. i've been using the mid bump as well.

i've found the roll off on the 421 to be really handy as it has different positions...

[soundguy]

cardioid mics have this thing called proximity effect. As you get closer to the capsule (in close proximity even) you get this effect (imagine that) of a bass boost. This is why singers all close up on a mic can sound fatter than three feet back. This is also why a mic an millimeter away from a roaring guitar cab can sound like shit. SOOO, one school says you want that close speaker thing but you dont want the proximity effect so much, so we give you (class, in unison) the roll off filter on the mic. This IS different from cutting at the console or the EQ later on. For those of you blessed with transformers in your signal path, if you cut the garbage presented from the cardioids little proximity gift, it means that the input transformer doesnt have to deal with it and isnt limiting those frequencies so you can run your mic pre hotter giving you a little more color from the amplifier versus the color from the capsule (remember the effect I spoke of earlier) that can be so cool in certain situations. If you leave it unfiltered and just EQ it later, it means that the mic pre is working totally differently with the unfiltered info versus the filtered info and the same goes for any limiters that you might have in the chain behind the pre. If you have a favorite limiter that always adds a little bottom (I dont know, something really erratic and obscure like an 1176) it can do you good to filter at the mic and let the 1176 add the boom if you know you dont need the proxiomity effect on your side. Then again, if you have a differential pre that is weak on the big bottom category, but you are looking for that talking 'bout mudd flaps my girls got 'em kind of quality then the proximity effect can be your best friend. For those of you recording on the often reported warmth of tape (I want the statistic of all the people who think tape is "warm" that know how to calibrate a tape machine), if you are recording at 15 IPS, maybe you've got a head bump around 80 HZ and if you've got a 421 up the asss of a celestion g12h well maybe you have this massive proximity around 80 hz and if you are smart enough to check your sel sync while you are tracking thats like, WHOAH, lotta 80 hz that wasnt there on the input monitor. Oh yes, the REAL magic of tape that the hystrical masses never speak to. Well, in that case you are like ALL psyched that you can run in and adjust the filter on your mic and cut it, just remember to monitor your sel-sync for previously fantasized FATTY WARMTH WONDERLAND because now your input monitor my seema little thin. It really all depends on your situation, so instead of taking my worthless advice what you should really be doing is flipping the switches and turning the knobs and listening to see which combo of flips and turns provides you with the best signal path that is most beneficial to your recording style.

you do have STYLE, dont you?

(cant teach that in recording school, altho I heard you can learn it online)

dave

[frank]

very well put, never thought about it...guess I get to switch flickin' and knob turnin'!

thanks

[cgarges]

Excellent as usual, Dave.

Here's another scenario:

You know you're not going to use much below 80Hz in the mix on your lead vocal. You track through an 1176 (or 160, or LA2A or whatever) and the vocalist gives you a nice, big plosive on a great take of a long, difficult phrase that you can't really punch. The compressor kicks in BIG TIME because of all the 30, 40, 50 etc. Hz information it's getting. What do you get? Massive, unatural gain reduction on the plosive at all frequencies, making it even more apparent. This effect can be reduced if the information that may not really be all that useful is reduced up front.

Not an absolute, but a consideration.

Chris Garges
Charlotte, NC

[soundguy]

you guys must have missed the news report which exposed me for the shill that I am.

I have to confess, Im not really a recording engineer, if it wasnt for my pet monkey to explain all this shit to me I really wouldnt be able to pull this act off.

Back to reality, chris's point is much more practical than any ideas I have about transformer vs. amplifier efficiency and to that I would add, if you are recording vocals with distortion again, echoing chris's idea, you might not really HEAR what 40hz is doing with your vocal track until you go and run it into a fuzz box then all you get is rumble rumble that is just fucking everything up MONDO especially if a limiter is AFTER the fuzzbox. Another good time to filter the mic, it keeps the distortion on the VOCAL and not all the body under it which can be cool on its own (I like a lot of bottom on guys with low voices) but is really working against you with lots of distortion. Much of the breath noise that gets accentuated with a fuzzbox goes away with a hpf before the amp.

dave

[cgarges]

Back to reality, chris's point is much more practical than any ideas I have about transformer vs. amplifier efficiency and to that I would add, if you are recording vocals with distortion again, echoing chris's idea, you might not really HEAR what 40hz is doing with your vocal track until you go and run it into a fuzz box then all you get is rumble rumble that is just fucking everything up MONDO especially if a limiter is AFTER the fuzzbox. Another good time to filter the mic, it keeps the distortion on the VOCAL and not all the body under it which can be cool on its own (I like a lot of bottom on guys with low voices) but is really working against you with lots of distortion. Much of the breath noise that gets accentuated with a fuzzbox goes away with a hpf before the amp.

Dave,

Be sure and thank your monkey for further illustrating my point.

Chris

[soundguy]

man, if some of the folks on the board think Im an asshole they have like NO IDEA how pissed my monkey is for stealing his fire. If that furry thing could type, Id be well fucked. But until then, charade continues.

cue evil laugh and spooky music.

dave

[Derrick]

Wow. This gives me lots to try as I like tubes, transformers, and distortion, as well as ramming mics up the ying-yang of old celestions operating at near thermal melt down. The concept that frequencys not really heard anyway are effecting other devices so you should play with cutting them and see how these other devices react is really something that will be useful for me to experiment with! These are just the kind of tools I aquire on these boards. Like I said... wow!