Shure Unidyne III 545 vs. SM57 ?

[Kazrog]

This topic has been covered before, but none of the old threads ever arrived at definitive answers. I've been doing some research lately on this subject, and have compiled the most complete set of info I can find, but I still am wondering what else is known on this subject. To give this my own test, I just scored a couple of vintage Unidyne III 545 mics for $40 out the door on eBay today, and I am eagerly awaiting them in the mail.

Here's what I've found in my research thus far:

1. Recording geeks have come up with all sorts of interesting sounding theories about the difference between the Unidyne III and the SM57, mostly attributing the sonic difference to Shure switching manufacturing from the USA to Mexico in 1985 (or 1975, depending on who your source is!) Obviously, with so much conjecture and rumor-mongering being passed off as "fact," it's been a frustrating (but intriguing) research project for me.
2. Several different models of the Unidyne III / 545 have come out, mainly to accommodate all of the myriad bizarre mic cable and mic mounting standards that predated modern XLR, some offering switched operation, some not, etc. They've been produced continuously from 1960 up through the current production model (Shure Unidyne 545 SD) available today. That's right - Shure still makes the Unidyne III 545, they never stopped as far as I know - and while it is related to the SM57 in many ways, it's clearly not the same mic.
3. If we look at the manuals for the 1960 version, and today's version, it's clear that very little (other than measurement methods, perhaps) has changed in terms of the frequency response graphs - but that both the 1960 and the 2009 versions of the Unidyne III bear the same considerable frequency reponse differences compared to its close relative, the SM57.

Here's a comparison of the current, 2009 frequency response graphs as found on Shure's website:

Shure SM57:


Shure Unidyne III 545 SD:


These frequency response graphs pictured above are current, 2009 data based on production models, and they show that the Unidyne III sounds particularly different in the high range - quite possibly giving it a nice boost in that area that many engineers find desirable and "mojo" worthy.

So is the difference between, say a 1960 Unidyne III and a 2009 SM57 really the result of different factories and manufacturing standards, or is the difference primarily because these mics are simply not the same model?

Only way to know for sure is to test a vintage Unidyne III against the current Unidyne IIIs. So my main question is: Has anyone done this?

Hopefully I will have the opportunity to do this at some point. I'm not sure exactly what vintage my recent eBay win is, since it was apparently part of a big haul out of an old radio station closet and the seller isn't a gear geek (hence I got a good price.) I'm hoping I got something at least made in the early 70s, but we'll see...

Anyone know anything else on this topic?

[chessparov]

Well I have the following Shure mics out of the Unidyne lineage.

548, 546, SM57 (made in USA circa 1980's), SM57 (recent-made in Mexico)

The SM57 USA has a smoother bottom and top end (also cleaner), than the other one ("dirtier" sounding)

So...

If you're comparing them to a LDC as a benchmark, most AE's IMHO would say the older one is "superior" sonically in terms of fidelity.

For my voice, however, as it is a "bluesy" sounding baritone either '57 would compare well to some uber$$ LDC vocal mic.

Of course, all 57's have fairly wide manufacturing tolerances, and each one will sound noticably different from one another IMHO.

I was surprised when discussing the SM57 with world class mic maker Wes Dooley,
how much respect he had for this microphone, INCLUDING the ones made down in Juarez, Mexico. As he kindly explained, even the 'ol RCA 77 ribbon mics had a relatively wide tolerance range also.

Hope this helps a bit, from a confirmed SM57/Unidyne III (or IV) lover.

Chris

P.S. The Shure 545 was used quite a bit on various Beach Boys lead vocals for Brian Wilson, he'd use it for the solo, then join the "gang" on a U47
in omni for the harmony vocals.

[Bob Olhsson]

A 57 is a selected 545 that's painted black.

[Kazrog]

Originally Posted by Bob Olhsson

A 57 is a selected 545 that's painted black.

Wow, well given your awesome portfolio, I will take that as the definitive answer. The main difference must be the "wide tolerance" that chessparov mentioned. Perhaps the difference between a 545 and a 57 is no more pronounced than two different 57s.

Thanks for the reply!

[kozsak]

I own 4 older (70's) Unidyne III 57's and 2 new Mexico 57's.

1. The Unidyne's all sound different from each other. One is sensitive to plosives. One is brighter, but not too bright. One is darker, but not too dark.

2. All 4 of the USA Unidyne's sound better than the new ones (IMO) By this I mean they have a more "pleasing" sound. Softer, smoother highs. warmer, fuller lows...

3. Each of the Unidyne's has a different pickup pattern. One is "hyper cardioid" and only picks up directly in front of the capsule. This is great for micing amps, but not so great for vocals.

4. The Mexico 57's sound almost identical. They both have a "faux" ground connection. (ie: no soldered ground wire-just a nub that rubs against the body.) They sound ok, a little hollow, maybe sort of "edgy". They have almost identical output levels. FYI These mics were bought at different times, so were probably not the same "manufacturing batch".

My real-world, non-scientific summary: Both new and old 57's sound pretty darn good. But the USA Unidyne 57's that I have sound noticeably better.

[Stitch333]

From Jim Williams:
I noticed the sonic changes on these back in 1990. I called a shure engineer I knew for an explanation. He told me no changes were instituted, but original stampers and dies were sent down to Juarez. If you know about record pressing, stampers wear out and need to be changed regularly. As far as I know, old stampers and dies are still being used. This was the main source for the sonic changes in the mics.

[kozsak]

Originally Posted by Stitch333

He told me no changes were instituted, but original stampers and dies were sent down to Juarez.

Not true. Take an old one apart and look. Then take a new one apart and look. They be different animals...

[Stitch333]

Originally Posted by kozsak

Not true. Take an old one apart and look. Then take a new one apart and look. They be different animals...

I merely quoted. You can read for yourself: PSW Recording Forums: Budget? Budget? We Don't Got No Steekin' Budjet => Info and history of Shure's SM57 along with mods?

and I just had a unidyne open the other day to fix a problem.

[Brad McGowan]

I've noticed the new ones have the transformer potted much more heavily than the Unidyne in your pic. I wonder if that can be a reason for the sonic differences?

Brad

[Stitch333]

Originally Posted by Brad McGowan

I've noticed the new ones have the transformer potted much more heavily than the Unidyne in your pic. I wonder if that can be a reason for the sonic differences?

Brad

Its hard to tell anything about the transformer in mine as it is bathed in glue...otherwise, does it look similar to the new 57s? I don't have one here for comparison...

Cheers!

[chessparov]

BTW an excellent complement to the SM57 is the Electro-Voice EV 635a, another desert island mic.

Bob Ohlsson's posts were the first ones that alerted me to this as a prospective top notch vocal mic, along with the '57/545. (thanks!) The frequency response of the old/new SM57 fits my voice a bit better without EQ tweaking YMMV.

Chris

[Brad McGowan]

Originally Posted by Stitch333

Its hard to tell anything about the transformer in mine as it is bathed in glue...otherwise, does it look similar to the new 57s? I don't have one here for comparison...

Cheers!

That's what I'm saying: the new ones are bathed in glue! Potting is fancy engineer-speak for glue.

Brad

[khai]

Originally Posted by chessparov

BTW an excellent complement to the SM57 is the Electro-Voice EV 635a, another desert island mic.

Bob Ohlsson's posts were the first ones that alerted me to this as a prospective top notch vocal mic, along with the '57/545.

Aren't you refering to the EV RE15/16 instead ?

[chessparov]

khai, yes Bob Ohlsson also has a high regard for the RE15/16 (per his past posts), along with the 635a omni dynamic. BTW a good way to listen to all these is to check out "youtube" videos of various performers.

Chris

[Kazrog]

So I got the 545s today. Turns out they're the newer ones, made in Mexico, but they definitely sound different than my SM57 of the same period. The 545s have more smooth high end, softer lows, and more pronounced mids. They are also significantly lower output than the SM57.

I've opened them up and my SM57 transformer is bathed in glue, but the 545s look just like the vintage one pictured in this thread on the inside - the transformers are held in with just enough glue. Perhaps the excess glue in the SM57 is there for live durability purposes, "drummer proofing," etc., whereas the primary market for the 545 is spoken word, broadcast applications.

I can't say I think the 545s sound "better" then the SM57, just different. For guitar cabinet miking I can see where the 545s could result in smoother tone that will sit in a mix nicer, but I also feel that the SM57 might sound better on vocals. Blending the 545 and the 57 on a guitar cabinet results in very satisfying, massive tone, that neither mic on its own would accomplish. Just my initial impressions, and I'm really glad to have these mics, I know they will definitely find use on almost every session I do now!

I'll be pursuing a true vintage 545 soon and I'll see if the new Mexican 545s I have sound anything like the old USA ones.

[Krank]

Just a harmless little bump as I'm curious about this too.

[Cameron Johnson]

I once had a Unidyne III 545SD as a kid... back in my early days of learning how to mic of a drum kit (around the same time I got into drums). I used it to mic my snare... needless to say, I loud, clumsy, aggressive metal drummer and took the windscreen AND the diaphram clean off. I was not impressed. I REALLY miss that mic.

I want more

[firby]

Originally Posted by Kazrog

So I got the 545s today. Turns out they're the newer ones, made in Mexico, but they definitely sound different than my SM57 of the same period. The 545s have more smooth high end, softer lows, and more pronounced mids. They are also significantly lower output than the SM57.

I've opened them up and my SM57 transformer is bathed in glue, but the 545s look just like the vintage one pictured in this thread on the inside - the transformers are held in with just enough glue. Perhaps the excess glue in the SM57 is there for live durability purposes, "drummer proofing," etc., whereas the primary market for the 545 is spoken word, broadcast applications.

I can't say I think the 545s sound "better" then the SM57, just different. For guitar cabinet miking I can see where the 545s could result in smoother tone that will sit in a mix nicer, but I also feel that the SM57 might sound better on vocals. Blending the 545 and the 57 on a guitar cabinet results in very satisfying, massive tone, that neither mic on its own would accomplish. Just my initial impressions, and I'm really glad to have these mics, I know they will definitely find use on almost every session I do now!

I'll be pursuing a true vintage 545 soon and I'll see if the new Mexican 545s I have sound anything like the old USA ones.

Why ?? At the end of the day, there are only so many toms that need to be mic'ed up. I say that you are turning into THAT GUY with 38 SM57s that went overboard. They all sound pretty much like an SM57.

Try collecting some ribbons, or large diaphram dynamics, perhaps some boundary microphones or electret condensors or full on groovey tube condensors.

My 2 cents.

Regards.

[Jim Easton]

Unidyne III 545 is an amazing mic for harp and vocals. Seen Paul Butterfield use this mic on many gigs.

His most famous live version of Every Thing Going To Be Alright...
YouTube - The Paul Butterfield Blues Band - Everything Going To Be Alright


His equipment list:
Paul Butterfield - Wikipedia, the free encyclopedia

Had the pleasure of seeing him at the original Woodstock in 69...

~

[Jim Easton]

Originally Posted by Stitch333

From Jim Williams:
I noticed the sonic changes on these back in 1990. I called a shure engineer I knew for an explanation. He told me no changes were instituted, but original stampers and dies were sent down to Juarez. If you know about record pressing, stampers wear out and need to be changed regularly. As far as I know, old stampers and dies are still being used. This was the main source for the sonic changes in the mics.

Jim I noticed that the newer edition sm57's had a little brighter top end but seasoned nicely with use and sounds like my older 57's.. Just a thought that this could be so with the 545.. a little "break in" time needed.

Man James, you have one serious studio.. World Class-!!

[RobbieNuke]

Nobody has mentioned the part of the mic that holds the cartridge. It's a black plastic on the 545's (and relatives) and metal on 57's. This would have more of effect on sound than variences in tolerance (comparing domestic to domestic, import to import). Also, probably near impossible to factor in the environmental/handling extremes that mics go through (except those whose life has been in a studio.).

[mikeyman]

i had ca nice 545sd that i trashed...
but another similar mic is the 58

[audiotech]

I have a really nice Shure 545 that I was experimenting with recently on a snare drum. Although it sounded OK, I much prefer an Audix I5 or an SM57. I have absolutely no idea how that 545 (complete with switch lock)got into my collection. Another Shure worth mentioning is the 548. Some how I got my hands on one of those also. If I'm not mistaken, I believe I saw that the 548 was predecessor to the early 57's.

Dennis

[Warfunkel]

Originally Posted by audiotech

I have a really nice Shure 545 that I was experimenting with recently on a snare drum. Although it sounded OK, I much prefer an Audix I5 or an SM57. I have absolutely no idea how that 545 (complete with switch lock)got into my collection. Another Shure worth mentioning is the 548. Some how I got my hands on one of those also. If I'm not mistaken, I believe I saw that the 548 was predecessor to the early 57's.

Dennis

The 548 was a Unidyne IV mic. The Unidyne III, which is used in the 57, was used in many mics during the 60's. I believe the 545 and 545S were the first Unidyne III mics. There was also a 565 which was the predecessor to the 58.