Sigh. I had been waiting for this moment a long time, having wasted much
of my teen and college years recording on $8 plastic mics held up with bent
coat hangers. I then lapsed into remembrances of all mics past I used
on guitar, from the radio shack $17 electrets, the $30 stereo condenser,
the $50 PZM and finally not long ago, the $125 Octava M012. But today
was the day, I have finally graduated into the league of the respectables
with a brand new SM81.
The first moment of perception in the first strum tells all. I
know that, so I slowly grab the pick, gently slide the guitar on my lap
to make sure the first sound it reproduces is not a clumsy clunk of a guitar
hitting the stand. I tap lightly on the guitar to set the preamp.
Then put the cans on.
Pause. (I know you are wonder how it sounds, I'll get to that...)
For those of you who don't know mics, The SM81 falls into the small condenser
category. Among condenser mics, these are sometimes loosely called
"instrument" mics as opposed to "vocal" (large condenser) mics. The
mic is ideal for acoustic guitars, acoustic piano, cymbals. I think it would
do well on acoustic bass, cellos, violins, mallets and hand drums.
I would not hesitate to try it on other things. It's really not a
vocal mic, but with a sock (windscreen ) over it it might get by in a pinch.
Shure says the mic is flat and has 20hz to 20kHz response. I don't
doubt that it goers low. Heh, I am ready to play the first strum and
go "What is that subsonic rumble!" Take off the cans and sure enough,
the AC just turned on and is blowing air in the room. Not to worry.
The SM81 has a 3-position low frequency filter (off, rolloff of 6db an octave
@ 100Hz and 18db an octave below 80Hz. These are quite gentle on the
sound and help you keep the good part of the bass response. There is also
a -10 pad for time when you need to record really loud things. You
won't need that for acoustic guitar, but its nice to have.
Newb: "So, How did it Sound, Tweak?!!"
Patience, my friend, patience. You know, that reminds me.
Why should one get a mic like the the SM81 when you already have a perfectly
useable SM57? Its really a matter of ear here. If you have your
SM57 working well on acoustic guitar and can't hear the difference, why
bother? Is the difference that great? Shure writes this
at their site:
Sound is a very personal thing. Only you can decide if you think
that one microphone is worth the extra expense when compared to another
microphone. Whether you will hear any difference between the microphones
will be dependent on the quality of the rest of the system as well as
how good your ears are.
Newb: "So is there a BIG difference?..TWEAK!".
OK, I hear you, but first, do you know when the SM81 was introduced?
Can you guess?
"Oh come on now Tweak stop frickin' toying with me!" Sigh.
Nope again. Way off. The SM81 was introduced in 1978 as "the
first truly reliable studio quality microphone." Amazing that it is still
the Mic of Choice for acoustic guitar and many other things. Go check
out the bluegrass forums and read the ever fierce mic debates at rec.audio.pro.
And it makes total sense. The acoustic guitar was very big in 79,
80, 81. In fact that's around when you start hearing the classic SM81
"So ARE you going to tell us about the SOUND?"
Yes. Right now. If you have an ear for recordings, you will recognize
the sound of the SM81. It's been on tons of records. When I
hit the first strum on this old classical guitar, I immediately shouted
"Yes!". The strings are clearly articulated, and the bass regions
come through with definition. In fact if you get too close to the
soundhole there is too much bass. With some mics its a problem getting
such bass out of them, not here. You can control it easily by
moving the mic so it's in front of the fret board and slightly angling it
towards the picking hand, away from the sound hole. Slightly turning
the mic away from the hole is like having your hand on a bass control knob.
It's an altogether wonderful sound capturing subtle nuance when playing
lightly and capturing the pick ripping through the strings when playing
hard. Try to EQ it. It's hard to find a better setting than
"So did you test it against anything?
You bet I did. One of first experiments was to try stereo miking
with an SM81 close in and a Neumann TLM 103 back about a foot. I really
liked that sound a lot as it gave good depth, but there was some minor phasing
going on so I know i have to experiment more with that. Then
i tried the typical X-Y approach with my Octava M012 at 90 degrees.
(see pic). The result was good, but not as rich as the previous experiment.
When I soloed the Octava then soloed the SM81 I could figure out why.
The Octava was much more a mid-rangy sound, not as deep, lush, or articulate
as the SM81. By the way, Shure does not sell matched pairs of SM81s
but they say on their site that the customer can be assured that the quality
of the sm81 is such that two mics bought at separate times will match well.
Guess we'll have to take their word on that for now. Interestingly,
at least to me, is that this mic sound excellent in mono. I liked
the mono recordings better than stereo. (of course, in a mix you may
need to eq for the sake of making room for other instruments). Oh
yeah, acoustic guitar through the SM81 blows the doors off an SM57.
It's a dramtic difference having the crystalline high frequencies come through.
Even with near-dead strings the sm81 will sound good.
So by my take the sm81 is a mic that sounds best without EQ and without
stereo processing. That should tell you something. I am very
pleased with the purchase, and i have no problem bestowing the Tweak's Pick
award for this product.
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FMR's Really Nice Preamp
TLM 103 by Neumann
Prices of Mic Preamps
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