Shure SM82

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I have a near perfect SM82, one small nic on the barrel. I've had it for years and never used it. What is anyone using for phantom with a line level output?

If I can't powered I may just sell it.
 
Any mic preamp with a pad should be able to handle it. Since the SM82 has a built-in limiter, the pad might not be necessary.

I do know that mic has a cult following, so it should be pretty easy to sell.
 
OK I looked at the TC specs and I stand corrected. However, that is a weird preamp:

tc specs said:
Max. Input Level (balanced), Pad 0/20/40/60: 0: -40 dBu, 20: -18 dBu, 40: 2 dBu, 60: 22 dBu
Sensitivity @ 12 dB headroom (balanced): 0: -82 dBu to -52 dBu, 20: -52 dBu to -30 dBu, 40: -30 dBu to 10 dBu, 60: -10 dBu to 10 dBu
Dynamic Range, RS = 200 ohm (unweighted): 0: > 56 dB, 20: > 88 dB, 40: >98 dB, 60: > 100 dB
Click to expand...

thus recording a vocal with typical condenser mic would require 20dB of pad and maybe 40dB. That is a very hot preamp, or maybe they just labeled the gain pot "pad" :)

Seriously, the unit is supposed to have selectable gain from +40dB to +70dB, so at +40dB and a 40dB pad, that's 0dB gain.

Does it work with the pad at 60dB? It should, since the SM82 can't exceed about 9dBu.
 
MS Hilarious- you are dead wrong!!!! A pad won't even touch it. Get a phantom power supply. Send the XLR out to a TS 1/4" line in, unbalanced. No problem. Or you send it to a preamp with variable input impedence, about 30-50 ohms. Whatever you do, *don't* plug it into any kind of mic input and turn on phantom power! With every gain control at minimum, I fried half of an Avalon AD2022 and blew the cones out of a pair of Sennheiser HD280 Pro's, which I was wearing at the time. More advice on SM82- If there's still a mercury battery in that puppy, remove it and dispose of it in an environmentally friendly fashion. Next- don't hit it so hard that the limiter kicks in. It's nasty and obvious. In other words. it's not a mic for high SPL's. It's a great acoustic guitar, mandolin, and banjo mic. It is excellent on voiceovers, and a pain in the ass to sing into. It sounds great, but the proximity field is very abrupt, so the singer really can't move. At all.
Don't give up on the mic. It rocks! Just get a phantom power supply and send the fignal to a line in.-Richie
 
Thanks Richard-

Yes the problem with MS Hilarious' idea is that the TC input, in Mic mode, is a mic level input that you are trying to put a line level into. You can set the same input to Line Level but it turns off the phantom in that mode.

I will try the external phantom PS and give that a try.
 
Richard Monroe said:
MS Hilarious- you are dead wrong!!!! A pad won't even touch it.
Click to expand...

Well I already said that I stood corrected, but perhaps you could point out the nature of my error. If a mic input can be set to +0dB, or less with a pad in front of that, how is this a problem? Line level is generally max +22dBu or so, and the specs on the SM82 indicate that it is max +15dBu output (looking back at the specs I see I missed a few dB). So where is the difficulty? Maybe I am odd in that all my pres can be padded to provide net negative gain, but I don't think so.

Honestly, sometimes when I read about people needing pads on LDCs for vocals I think I am in a parallel universe where different laws of physics apply. I've never needed a pad on a mic, ever (I record acoustic instruments, and avoid excessively loud drummers). To the contrary, I never seem to have enough gain. This seems to be similar in that I can't reconcile specs to other peoples' experiences, but they always seem to match mine.

Maybe I'll pick up one of these just to experiment.
 
mshilarious said:
Honestly, sometimes when I read about people needing pads on LDCs for vocals I think I am in a parallel universe where different laws of physics apply. I've never needed a pad on a mic, ever (I record acoustic instruments, and avoid excessively loud drummers). To the contrary, I never seem to have enough gain. This seems to be similar in that I can't reconcile specs to other peoples' experiences, but they always seem to match mine.
Click to expand...
I'm right there with you on that one. I've even recorded very loud amps and stupidly loud drummers with all kinds of dynamics and SDC's and LDC's, and have never once had to turn on a pad for anything anywhere.
 
Yo MS! I agree with you about pads, I almost never use them, unless I'm close mic'ing a cab with a condenser. But back to the SM82. Understand that I don't claim to be an engineer. I live in the real world, where that mic blew up a $2500 preamp with the gain set at 0, with 32db of headroom! I don't get how you can account for a *massive* impedence mismatch by using a pad. Now let's say I plugged my Shure 55C into a low-Z mic input. It's looking for 100,000 ohms. The mic input on my Avalon is about 2,000 ohms, give or take. Just turn on the pad, and you think I'm good to go with no matching transformer? A line level output into a mic level input doesn't work in the real world, with or without a pad. And the impedence mismatch cannot, according to the little I think I know, be expressed in decibels.
I'd be very interested in reading the technical explanation of all this, and a little bit of it, I might actually understand. What I can tell you, based on actual trial and (bigtime) error, is that the SM82 cannot be plugged into a low-z mic input and used safely. I can't claim I've tried it into a high-z input, which is closer to line level. I'm not really interested in blowing up any more equipment.-Richie
 
Richard Monroe said:
Yo MS! I agree with you about pads, I almost never use them, unless I'm close mic'ing a cab with a condenser. But back to the SM82. Understand that I don't claim to be an engineer. I live in the real world, where that mic blew up a $2500 preamp with the gain set at 0, with 32db of headroom! I don't get how you can account for a *massive* impedence mismatch by using a pad. Now let's say I plugged my Shure 55C into a low-Z mic input. It's looking for 100,000 ohms. The mic input on my Avalon is about 2,000 ohms, give or take. Just turn on the pad, and you think I'm good to go with no matching transformer? A line level output into a mic level input doesn't work in the real world, with or without a pad. And the impedence mismatch cannot, according to the little I think I know, be expressed in decibels.
I'd be very interested in reading the technical explanation of all this, and a little bit of it, I might actually understand. What I can tell you, based on actual trial and (bigtime) error, is that the SM82 cannot be plugged into a low-z mic input and used safely. I can't claim I've tried it into a high-z input, which is closer to line level. I'm not really interested in blowing up any more equipment.-Richie
Click to expand...

I thought of that. I suppose the excess current could toast a component or two, but I would hope a mic pre designer would anticipate the possibility, advised or not, that a user might plug a line-level signal into it. I don't know what the impedance of a pad is, of course it would depend on the pad, but I'd guess a few K ohms.

In any event there are plenty of pres where the mic and line inputs are the same connector, and there's a pad to account for the difference. I'd think the SM82 would work in that instance. I agree I won't stick it on a pre where that was not the design.

Back to the TC unit, the specs state it has a switchable -20/-40/-60 dB pad. Is the -60dB available on the mic input?
 
There is only -20 and -40 pad on the TC Gold Channel that I can find.

I did get it working with an external phantom power supply. The mic has a little bit of hiss to it, but I am used to Neumans and 414s.
 
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