Lack of a transformer is only part of the equation and difference, as I understand it. The SM7b has a larger capsule, and the sm57 is moving coil, which I think differentiates the two as well.

I've owned two 57s for nearly 20 years now and a SM7b for about nine years. When I first got the SM7 I did numerous comparisons between it and my 57s and 58. There's really no comparison IME.

As for gain, the Fethead is a good option. I have a Cloud Lifter and love the combination. The SM7b is a great mic for reasons already cited.

The SM7b is a moving coil mic, too.

the sm7b is not larger either. im leaving now thank you.

Sure is. As well as DreamCastel and dozens and dozens of other handles. I think he's been at least twelve handles just this year.

Larger diaphragms produce more output -- not less.

Try the Great River MP1NV, its a really great option with the SM-7B, IMO

I do want one of these, especially for tracking single things at home! I have a Pacifica and 4-710d currently. I also want a UA 6176 though.. and a bunch of other stuff!

Actually SM7B has same size capsule as 57/58. The difference is the humbucking coil and the slightly differently opened plactic grill infront of the capsule, that is actually a hight frequency resonator. Take it off and you will loose lot of presence.

SM57 mod (transformerless) gives you a similar sound for 1/3 the price. Ok, you are missing the inductor low & high cut filters but more or less the same sound. The output transformer in 57/58 is actually magnetically damping the membrane so therefore the sound is mid heavy = good for snare ang electric guitar. Without the transformer more scooped and smooth like SM7.

I recommend doing the transformerless mod to Beta mics. I have done to my beta56. Before they sounded (on toms) like someone beating an empty pizza box, now the best fat like you would want toms to sound. Because they have neodynium drivers the volume drop is not so huge compared to transformerless SM57 (same output level as SM7).

BTW the Beta52 is different, it does not have a transformer but a 400Hz passive notch filter. I have installed a bypass switch in mine.

Main reason is that the cage keeps your mouth about 3 inches away from the capsule. Take your 57 and talk at 3 inches distance, see how much output it gives compared to being right on it. From the Shure website...

When selecting a preamp for the SM7 for voice-over work, make certain the preamp has a minimum 60 dB of gain. Here's why:

a) With an acoustic input of 84dBSPL - typical speech level at 3 inches, the output level of the SM7 is -69dBV.

I never really noticed. I plug mine into my API A2D (which is basically a 312) and crank it. Sounds great that way.

I agree with Kennybro…. set the 58 3" away, add the same foam and its not much difference in gain.

The sensitivity spec is a small difference between the two mics you list. 1.85 vs 1.12 approx... its all relevant I guess? I think of mics from 1.00 mv/pa to 28mv/pa in total across all types, so dynamics at 1.2 to 1.85mv/pa seems a small difference.


I did the 57 and 7b comparison as many have and didn't hear a drastic difference. But the SM7 has much more for the extra $$ as in the body, the foam, the cage, the designed housing with filtering...I wish I had never sold mine. Back then they were $299 new and now they are $399 new.

We all hear things differently. To me SM7B is way smoother, more lows and highs than 58/57 that are basically the same mic with different screen. SM7 Needs way more gain. But agree with the price. SM7 is WAY over priced. There are many as good dynamic mics with less money. Like Sennheiser e9** series. Many good vocal mics there.

The cost is mostly in the body of the mic and the switching options. It's a robust, professional rig designed for commercial radio use where an interrupted signal from a mic means dead air. And the caged distance keeps proximity in control to some degree. In light of all that, I don't think it's overpriced, except for the stand screw attachment. A PITA. It would be so easy for Shure to rework it with the same basic design, and have a really nice screw/stand attachment.

But that body and the extra electronics certainly affect the sound of the mic. I agree that they sound different than a 57. Nothing wrong with good old 57, but the 7 is different. More polished sounding right out of the box. The sound going into the mic bounces around that cage and resonates in the body in nice ways somehow. I think Shure did a ton of R&D, but they also got a bit lucky with this one. There's a reason it's been a radio announcer classic for decades.

The answer to the OP's original question lies in the spec sheets.

The sensitivity of the SM7 is -59 dBv at 1Khz
The sensitivity of the SM57 is -54 dBv at 1Khz.

The higher the negative number the lower sensitivity. -59 vs -54 means the SM58's output is 5dB higher then the SM7 at 1Khz.
The SM58 rolls off below 50hz and above 15K so the SM7 will have higher outputs at extremely high and low frequencies. In your mid vocal ranges the SM58 should be noticeably louder.

As to why? There are the physical materials and electronic differences which are going to make a difference.
One of the bigger ones is going to be the transformer. Just like guitar pickups, when you add more winds you get more output but you loose frequency response as the Q or the coil gets narrower. The SM7 has a very broad frequency response and in order to get that extra 5K up top they undoubtedly needed to use a lower transformer ratio compared to the SM58. The transformer output impedance is about the same at 150 ohms, but the primary coil and the dynamic coil impedance is likely lower. The dynamic coil size, type, strengths just like pickups may be quite different too.

Keep this in mind too. Try comparing a Hi Fi speakers SPL to a guitar speaker. A Hi Fi speaker may only be in the 80's or low 90's whereas a guitar speaker is typically in the upper 90's up to 110 or so. Again, the more efficient, hotter sensitivity produces a louder signal but it comes at a cost of a narrower frequency response. Guitars are mostly midrange instruments so they can get buy sounding OK even with nothing above 6K or below 150 hz

A lot right but still... No "lower transformer ratio". Just the coil.

"What are the differences between the SM7B and SM5B?
Both are cardioid dynamic microphones intended for broadcast voice applications. Both are transformerless."

Shure SM7B | RecordingHacks.com

You know what differences are , right?

Are you kidding me?

The other one is transformerless dynamic reproduction version (B) of SM7 and the other is a boy band from Walthamstow.

SM57 on Steroids: The Shure SM7(B) Story | Shure Blog

It's all here, Unidyne III element etc...