sm81 vs sm57 ...how do they compare??

[N_O_VATER220]

im currently using a sm57 to record my acoustic, just for my personal home use. Im thinking of getting a sm81 but was wondering what i could expect the diffrence in sound to be because the sm81 is quite expensive for me anyway.

[Fran Guidry]

This is exactly the very first upgrade I did in my recording evolution. By far the most significant difference between these two mics is the sensitivity. The SM81 has much greater sensitivity.

SM81: Sensitivity (at 1,000 Hz)
Open Circuit Voltage: -45 dBV/Pascal (5.6 mV) (1 Pa = 94 dB SPL)

SM57: Sensitivity (at 1,000 Hz)
Open Circuit Voltage: -56 dBV/Pascal (1.6 mV) (1 Pa = 94 dB SPL)

This difference means that you have to turn your preamp up a _lot_ to match the SM57 to the SM81.

Outside of this there are differences in frequency response. The SM57 is tailored for PA use, so it has a presence peak of about 6 dB at 6 khz. The SM81 has (if the factory curve can be trusted) a very flat response. The response of the SM81 also extends to 20 khz, while the SM57 has a high frequency rolloff starting around 12 khz.

The SM81 low frequency response is also extended compared to the SM57. The 57 is expected to be used very close to the source, so the response is tailored to reduce proximity effect. This was the second most obvious difference to me when I did careful comparisons and both mics were placed about 18" from the guitar. The SM57 sounds a bit bass light in this arrangement.

Here are the two spec sheets with frequency response and polar pattern diagrams:

http://www.shure.com/idc/groups/publ..._specsheet.pdf

http://www.shure.com/idc/groups/publ..._specsheet.pdf

Fran

[Bob Womack]

Amen to Fran's post.

[Scott Whigham]

A cool site that I like to use is the Microphone Database at http://recordinghacks.com/microphones. You can easily view the frequency response of one mic relative to another. This doesn't give you the full picture but it helps with a basic understanding, I think.

Here's a comparison of the SM81 to the SM57:



You can quickly see that there are big differences between them.

HTH!

[moon]

The 57 loses a lot of transient information.

[donh]

Originally Posted by moon

The 57 loses a lot of transient information.

You, sir, are a master of understatement!!!!!!!! :-)

/what a diplomat!
//and a very kind fellow to boot!

[Ty Ford]

Of course it loses transients, it's a dynamic mic.

Think about the difference in mechanisms. A dynamic has a diaphragm attached to a coil of wire that moves in a magnetic field when hit by sound. The mass of the coil keeps the diaphragm from moving as much as a condenser.

A condenser has a diaphragm that is not attached to anything except the frame they rig it on. With nothing attached to it, it moves a lot more freely. So much so that designers have to figure out how to reduce it movement.

The SM81 deserves a place in mic history, but for me, it's sort of like the beyer m160. The idea of these mics is frequently better than the mics themselves. There are better mics these days.

Want to get a scarily accurate mic for a great sounding guitar? Try a Gefell M296 omni condenser. Here's a recoding with my D28s (apologies to Mr. Prine) A little thin on a lap top, but play it back on something else. One mic, on both voice and guitar, one pass. I think I had the mic about head high and pointed down to catch both my voice and the guitar. No EQ, no nothin.
http://db.tt/8SXdmOPG

Regards,

Ty Ford

[Bob1131]

Originally Posted by Ty Ford

...The SM81 deserves a place in mic history, but for me, it's sort of like the beyer m160. The idea of these mics is frequently better than the mics themselves. There are better mics these days.

No matter what the topic, there is always a "better" item attainable if you are able to spend the money.

SM57 = $100

SM81 = $350

M296 = $1,500

[j3ffr0]

If I was going to buy a SDC in the $300-$400 range for recording acoustic guitar today, I'd consider:

Shure KSM141 (Although I don't own one, I love the idea of being able to switch between cardioid and omni)
Shure KSM137 (cardioid version of the above)
Audio Technica AT4021/4022 (a relatively new mic that has received some good reviews)
Beyer MC930 (everyone who has these loves them)
Used AKG 460 or 451

All of these will do much better than the SM57 and at least as good as the SM81 if not better.

[flagstaffcharli]

Originally Posted by Bob1131

No matter what the topic, there is always a "better" item attainable if you are able to spend the money.

SM57 = $100

SM81 = $350

M296 = $1,500

Exactly.

You can save money forever for better gear. But all the time you're saving money is time you're not making recordings. I was just reading about the recording of Sgt. Pepper's. Having only four tracks didn't stop George Martin and the Beatles from doing what they wanted to do. There is quite a bit of tape hiss on the record from George Martin bouncing tracks around so he'd have available tracks for recording. A lot more hiss than on many of our home recordings. So what? It is arguably the most influential pop/rock record ever.

Certainly we all don't have Abbey Road and George Martin available to us, but I think it's important to decide to make recordings (if that's what you really want to do!) with what you have and what you can afford. We can all take a lesson from Sgt. Pepper's. The Beatles didn't wait for an 8-track machine to arrive. Jump in the game and make music. Having the best (expensive) gear doesn't guarantee good results, and having affordable gear or a less than ideal space doesn't mean you can't make wonderful music. You can make a great recording just singing & playing into one very basic mic if you have the material and performance skills. I believe that.

Coincidentally, I just bought an SM81 (used, for very cheap) and a Beyer M160. To me, those are some pretty nice pieces of gear and they represent a significant investment. Maybe someday I'll be able to buy the Gefell or a Royer I've listened to Ty's recordings and they sound very, very good - the performance and material is there in addition to very high quality audio production. I don't doubt that he is recommending good gear. But the Gefell isn't even in the same neighborhood as the SM81 in terms of price, and the SM81 probably isn't a bad choice at all for recording an acoustic guitar. Most likely it'll be an improvement over the 57 depending on what you're trying to do.

[Mr Fixit eh]

[QUOTE=flagstaffcharli;2883818]

Exactly.

You can save money forever for better gear. But all the time you're saving money is time you're not making recordings. I was just reading about the recording of Sgt. Pepper's. Having only four tracks didn't stop George Martin and the Beatles from doing what they wanted to do. There is quite a bit of tape hiss on the record from George Martin bouncing tracks around so he'd have available tracks for recording. A lot more hiss than on many of our home recordings. So what? It is arguably the most influential pop/rock record ever.

You can make a great recording just singing & playing into one very basic mic if you have the material and performance skills. I believe that.

[QUOTE]

This is an encouraging comment to me where I'm at the beginning of my recording journey.

Steve

[donh]

Originally Posted by Bob1131

No matter what the topic, there is always a "better" item attainable if you are able to spend the money.

SM57 = $100

SM81 = $350

M296 = $1,500

Heil PR30 = $249 and it *smokes* the SM81 (I have never met the M296 so I have no opinion about it)

[Fran Guidry]

Originally Posted by donh

Heil PR30 = $249 and it *smokes* the SM81 (I have never met the M296 so I have no opinion about it)

Don, could you please whip up a pair of same performance level matched clips demonstrating this??

Fran

[Ty Ford]

Originally Posted by Bob1131

No matter what the topic, there is always a "better" item attainable if you are able to spend the money.

SM57 = $100

SM81 = $350

M296 = $1,500

Dear Bob,

You forgot the EV 635a and MXL MCA SP-1.

We are a wide community. I am constantly surprised by how much people will spend on things or how many guitars they own. I sometimes get the impression that, when I mention more expensive gear that there's this knee-jerk reaction by a few people here to the price point. "No! Don't do that!!! That's way too expensive!!!" Mostly without having any experience with the mic mentioned.

Keep aiming low and that's what you'll get. I hope you don't mind if I continue to inform people, some of whom are able to afford a more expensive mic (or whatever), that there are solutions that do sound better, even though they cost more. (Not that cost alone determines how good something will sound.)

While I do own a few pieces of really good gear and have learned how to use them, I don't own most of what I report about. These mics are sent to me to be reviewed for published articles and then returned to the mfgr.

The Sgt. Pepper anecdote comes up frequently, but please keep in mind that the professional 4-track the Beatles used (two I think actually) bear little resemblance to what we think of today. Those 4-tracks were state of the art at the time, and VERY EXPENSIVE. The mics, preamps, space and people involved were also exemplary. Not what you're going to find in anyone's home studio by a long shot.

You want to get into this cheap AND easy? Get the Sony M10 recorder I reviewed about a year ago. Light, stereo, long battery life, on board mics and external line input.

Regards,

Ty Ford

[Bob1131]

Originally Posted by Ty Ford

Dear Bob,

You forgot the EV 635a and MXL MCA SP-1.

We are a wide community. I am constantly surprised by how much people will spend on things or how many guitars they own. I sometimes get the impression that, when I mention more expensive gear that there's this knee-jerk reaction by a few people here to the price point. "No! Don't do that!!! That's way too expensive!!!" Mostly without having any experience with the mic mentioned.

Keep aiming low and that's what you'll get. I hope you don't mind if I continue to inform people, some of whom are able to afford a more expensive mic (or whatever), that there are solutions that do sound better, even though they cost more. (Not that cost alone determines how good something will sound.)

While I do own a few pieces of really good gear and have learned how to use them, I don't own most of what I report about. These mics are sent to me to be reviewed for published articles and then returned to the mfgr.

The Sgt. Pepper anecdote comes up frequently, but please keep in mind that the professional 4-track the Beatles used (two I think actually) bear little resemblance to what we think of today. Those 4-tracks were state of the art at the time, and VERY EXPENSIVE. The mics, preamps, space and people involved were also exemplary. Not what you're going to find in anyone's home studio by a long shot.

You want to get into this cheap AND easy? Get the Sony M10 recorder I reviewed about a year ago. Light, stereo, long battery life, on board mics and external line input.

Regards,

Ty Ford

Thanks for the snarky reply, Ty. I have no problem with expensive gear or recommending expensive gear. My point was that your recommendation was not appropriate to the thread topic. Read the OP again:

Originally Posted by N_O_VATER220

im currently using a sm57 to record my acoustic, just for my personal home use. Im thinking of getting a sm81 but was wondering what i could expect the diffrence in sound to be because the sm81 is quite expensive for me anyway.

If the OP regards the SM81 expensive, why on earth would you recommend something that is four times the cost?

I respect your expertise and generally find your comments helpful, Ty. In this instance, I don't think you were much help to the OP.