Ever wonder what influence a shell has on the tone and volume output of a mic element? Well, I recently had a chance to find out. In a little barter deal, I was making a couple of mics for a fellow forum member (AW), and for one of them I was rehousing a dynamic element from a Panasonic DM21A into a vintage Turner +2 shell. I happened to have more than one DM21A, so I could make a video comparing the tone of the stock DM21A stick mic to the one I rehoused in the Turner shell. The video is below:
I want to point out that Zhin made a good point in the YouTube comments for this video. The shell shape also affects ones ability to get a good cup, and this may account for some of the tonal difference. Never-the-less, I think you will all agree that there is a HUGE difference in volume and tone between the two shells.
Also, I just want to make it clear that my point with this video is not to say that the element doesn't matter. It does. All else being equal, a better element will sound better. It's common sense. Also, a dynamic element is going to sound different than crystal or ceramic, no matter what you do. Again, common sense. Rather, my point is that there are also other factors that influence tone and volume in a mic, and I just wanted to point out that these other factors make at least as much of a difference to the characteristics of a mic as does the element. To put it more metaphorically, there is at least as much mojo in the shell as there is in the element, and there is probably more mojo in the person who makes the mic than anything else. I'm talking knowledge and experience here, which is why you are guaranteed to get a great sounding mic when you buy from a respected technician like our own Greg or rharley.
The DM21A is not a well known "harp mic", but is rather a mid-level vocal mic, costing probably $30 new. I made this mic using the techniques I show in my "DIY Bullet" mic video ( http://www.youtube.com/watch?v=n0WYuWPRKlw ), which shows how to make a "bullet" mic using parts you can find at any hardware store and a decent dynamic element from a middle-of-the-range vocal mic. Give it a try if you want, but you probably shouldn't go cutting up your $100 sm57. In fact, those mics have more going on inside them than a middle-level dynamic mic, so you'd really need to know what you were doing if you were going to re-house them (this is why we have people like Greg who does what he does with these mics). Stick to a $30-40 mic for this project.
Also, AW himself was kind enough to make a video of him playing this mic in comparison to some others. He doesn't do YouTube, so I'm linking his video from my dropbox account: http://dl.dropbox.com/u/7325374/Comparing_3_mics.flv. The first mic he's playing is a mic I made for him using a modern Kobitone ceramic element housed in a spice bottle. The second is an ultimate57, made by our own Greg Huemann. The final mic is the Turner that I made for him with the DM21A element inside. He plays them all through his Vox Mini3. In the first part, he plays using the "Tweed 4x10" amp model with a little delay and a little reverb. In this set, he was getting a little feedback on the SM57, so he had to turn it down for that mic a little. In the second half, he plays each of the three mics at full volume and without any effects or modeling. I think each mic gives a unique tonal flavor, and AW does a really good job of demonstrating that for us. Thanks AW! ---------- == I S A A C ==
isaacullah,..very good job on the demo an the mics ya built,..Shure CM /CR's are not the only elements for good harp mics,..I built a Lil' AKAI for Bluemoose that I believe he'll take to the grave,.. You don't need to spend 300-400 bucks to get a good harp mic as you prove in this video.
Isaac - Can you confirm these 2 elements sound identical when in the SAME (i.e. original) shell? Often there are differences between elements of the same exact model.
Not only does the shape of the shell influence cuppability, ( In your video I can see that the stock mic has a spherical ball screen - those are almost impossible to get a tight cup with) it also determines where the element is placed relative to the front of the mic - and that makes a difference too.
I'm willing to be swayed but I am still of the opinion that different shells make very little difference compared to other factors such as difference between elements. Shells make no difference for most crystal elements as they are not vented to the rear. Dynamic elements are, however - including CM and CR - and the size of the chamber behind them, as well as the degree to which that space is sealed, DOES have a small effect on tone. This is even true for modern elements like the SM57, which is why many players believe the Ultimate 57 (which has slightly more rear chamber area) sounds better than a stock SM57. ) ---------- /Greg
Isaac: your sm57 element in the turner shell sounds good. I have a couple of sm58's, and thought about taking one of them apart to see whats up, and possibly put it into a 520dx shell. what size VC did you use, normally I don't use a VC in my mic's, but these elements sound pretty bright and thought maybe some control might be good.? I'm really interested in what it might sound like, hopfuly a little dirtier than in the long housing.
@stones: having tooled around with several vocal mic elements in bullet housings, I'm with Greg on this one and I doubt if it will make a big difference, except in terms of cupping and proximity of the element to your harp. I have seen Ron Sunshine demonstrating elements for sale on ebay with no shell, and even they don't sound markedly different.
If you're like me, you'll probably want to have a go for yourself to see anyway, and having spent the time and effort on it you'll probably be more inclined to notice an improvement than not! Whatever, it will be easier to hold and more stylish. Have fun. ---------- Lucky Lester
Last Edited by on May 17, 2011 1:48 AM
Thats kind of what I thought, but like you said it's fun to mess around with this stuff. Isaac's demo was good but honestly not alot of difference between the two, other than the VC on the turner. I've got a collection of CM's and CR's that I've accumulated over the years, and like Greg said the differences between like elements is hugh. I've had CR's that sounded like crap and the few that doo work good I've kept in my secret stash. I just like to fool around always changing things up and around just to see. I like these kind of threads and do think Isaac did a good job of demo'ing his mic's.
@Greg: Yeah, I A/B tested all the mics in my spare parts box in preparation for making AW's mic, and I could not hear any difference between any of the DM21A's I had. In the end, I just "picked one", so I'm pretty sure that all the tonal differences between the two stem from the re-housing. Now, I'm sure that your point about cupping (also made by Zhin) has A LOT to do with the final tone. In hindsight, I probably should have also played both mics UNCUPPED on this vid too, but it's too late now. There was definitely still a tonal difference uncupped, but it was way more noticeable when cupping, so that probably has a big influence. In the end, I think that there are four things making the difference. 1) the basic tonal response (frequency response) of the mic is changed by removing the back part of the small dynamic element capsule and exposing the back of the element to the bigger chamber of the bullet shell. 2) proper gasketing aids in that process, and also allows the element to be overdriven more, providing higher signal peaks and also changing the tone. 3) moving the element closer to the grill allows you to play right up in front of it, allowing you to overdrive it more, and get more volume and change the tone. and 4) the bullet shell is way more cup-able than the ball of the stick mic in that you can get a really tight seal.
I wish I had some audio analysis equipment, as it would have been really cool to be able to measure the change in frequency response, output level, and wave-form, before and after (and cupped and uncupped).
@stones: I just wanted to clarify that this mic does NOT have an SM57 element in it. It has an element from a Panasonic DM21A. I can't tell you whether or not rehousing an SM57 is going to make any difference to the tone/volume you get out of it as I've never worked with an SM57 element before. I do know that there is more going on with the SM57 element than with these middle-of-the-range dynamic mics, and that the SM57 element is longer and more complex-looking. I imagine that the SM57 is "over engineered", and so won't be AS affected by shell changes as these other elements.
@didjcripey: Glad to see that the spirit of tinkering is still strong on this forum! Yeah, I strongly advocate for folks to try this out for themselves. As they used to say on the old kids show "reading rainbow": "But don't take MY word for it..." :) ---------- == I S A A C ==
sadly, there is always mixed emotions, when I pass on a good harp mic to someone. They are all different. And I want em all for myself! But seriously folks, like Isaaculla says, " you can get good tone by..thinking a little about microphones, frequencies, and tonal response" ..sounds like you have Gear Acquisition Syndrome. Thanks again.
---------- Why is it that we all just can't get along?<
Last Edited by on May 18, 2011 10:42 PM
