I believe some of you guys like the Unydine mike for harp? Hopefully I'm not wasting your time with old news here but here is this bit of info from my favorite recording geek magazine Tape Op. Basically you can either get your SM57 or 58 modded, get the transformer and do it yourself or by one setup for you so you basically have a Unidyne. This from the review : "I've heard of SM57 transformer mods for years. Producer Stuart Sullivan [Tape Op #94] first clued me into it, saying that the old Unidyne models of the Shures had better transformers, but to keep prices down over the years, the company had compromised a bit on transformer quality. When I got that information from Sullivan, my mind thought, "Must find old SM57s," rather than bother to replace the transformers themselves."
Here's the link to the whole review, see maybe guitar players {me} aren't that bad after all.... : )
http://tapeop.com/reviews/gear/96/ami-t58-transformer-for-shure-sm57-sm58-mic-mods/
Last Edited by zellecaster on Jul 20, 2013 6:30 PM
The term "Unidyne" applies to many different Shure mics. Some were high impedance, some were low and some were dual impedance. Each of those had a different transformer. The early PE54's had a single impedance, high impedance transformer- they make GREAT harp mics. You COULD use that transformer with an SM57 to make it a high impedance mic.
The older transformers colored the sound more than the newer ones - probably because they were still hand wound while the newer ones are robotically wound.
The original SM57's had single impedance, low impedance transformers as they do today - but the transformers were not the same as the current ones. They are easily identified because they have a black ground wire going to the element - the current SM57's have only signal (green and yellow) wires going to the element. I like the way the old ones sound better for harp. But they're very rare and hard to find.
The dual impedance transformer used in the later PE54's and early 545's is indeed different than the current one with the same differences as described above.
I did this mod to my SM57; took out the transformer after boiling the barrel in water.
I plug the mic into a Radial Re-amp tranformer, and then the amp. It sounds more transparent, and does have more low end, although it is not punchy. More like lower harmonics.
But I love the simplicity and I love playing through iron. I'd recommend a big fat transformer to everyone.
@Greg maybe you can answer this - what is my output impedance now, with no mic tranny but using the big Radial re-amp? Just curious, thanks
Interesting. I REALLY like the pyle 57 copy. I might try this with one of them. If i mess it up they are very inexpensive, so no biggie. I also want to add a volume control and possibly a 1/4" connector. Is there enough room in the 57 to add this all internally? I don't really like those 1/4" plugs that hang out the end.
I want to do this to one of my DM13s also. Because they have a built in chord which is kindof a pain sometimes. Especially storage wise.
An external volume control that i could swap from mic to mic could be nice. But i would like to have a 57 and dm13 all tricked out. ---------- "Trust Those Who Seek The Truth. Doubt Those Who Say They Have Found It."
Last Edited by Killa_Hertz on Mar 26, 2016 7:27 AM
@Killa I was not aware of the Pyle copy, just found it on Amazon, for $13 how can you go wrong. I'm going to get one and try it out, why not. Love doing things on the cheap.
With the transformer removed, there is a lot of room in the barrel of the 57.
the ami transformer has been available for the last ten years, it is very highly regarded. it is low impedance. it may be possible to have one made that is high impedance.
sadly the man behind the mic. oliver archut passed away a few years a go. if you are a microphone geek, his story is fascinating. i'll see if i can dig up some of the info.
valley duke, if you have removed the old transformer, that is the hard part. you are a prime candidate to try out the ami transformer. just insist they make it high impendance.
ValleyDuke. .. YUUUUP. $13. They really are pretty good. I know a couple others on the forum have found them aswell. Lmk what you think. One caution, Dont use that cheap xlr - 1/4" cable that comes with it. After about 2 days of using it i lost the end in a pedal. Tragic.
I was talking of replacing the xfmr with a hiz. That way you need nothing new to plug into. I use a line xfmr now, but it would be nice to just be able to use 1/4" cable.
1847 .. there are no HI-Z Xfmrs that are available stock? Getting one made special must cost a good bit more. ---------- "Trust Those Who Seek The Truth. Doubt Those Who Say They Have Found It."
not sure they would charge any more for a high impedance transformer, heck at $85.00 dollars that is already an outrageous sum. i will call them tomorrow to check.
the bussiness end of a mic, is the capsule or element. at the end of the day you will have a mexican 57 with a very nice transformer.
it may better suit your needs to use the 85 dollars and make an offer on the crystal element mr. hart is selling. a crystal mic is the gold standard of harp mic's.
Wow ... $85 .... thats crazy. Ill figure something else out first. Idk rather just start with a high Z mic like the Akai DM13 n throw a VC and a 1/4" connector. It would be worth it for a nice bullet mic or something.
Its not worth $85 to not have to use a line matching xfmr and use 1/4" cable on my 57. Especially if i use the pyle.
Speaking of which, What if you took the guts out of a line matching xfmr and put them into a 57? Or something like that? There's gotta be a better way. Line matching xfmrs are only like $20.
I know nothing about mic modification so sorry if these are dumb questions. But im am electrician and i Also know my way around a soldering iron. So I can make something work. Are there any cheap mics that have hiz xfmrs that will work on the 57 that i could part out? Or something along these lines? ---------- "Trust Those Who Seek The Truth. Doubt Those Who Say They Have Found It."
I looked for the transformer in my pylepro when I got and found none. If it is absent then I could imagine that's one the ways they keep the costs down. But it's a concern as an accidental application of phantom power might ruin the element, without a transformer to block the DC voltage. I'm not going to try it.
I read of lots of 57 mods, including removing the transformer altogether. It must have the Shure designers tearing their hair out, as they've carefully designed in a particular frequency response. But I guess people love to tweak - and 'different' is often considered 'better'.
In the non-harp world, then surely 'better' would be a less colourful transformer to give a more faithful response. In the harp world I guess it's a different story, where colouring the sound could be a desirable thing.
Surely a niche business opportunity: hand wound audio transformers for harp players?
Personally, if I wanted a hi-Z SM57 with a volume control, I'd buy an Ultimate 57 where it's all been done for me. And you end up with a lighter mic. But I know other people like the DIY. On MBH I have seen some pics of nice examples of your DM13 with VC and 1/4" socket. I don't know how they fix the socket in. I suspect epoxy resin must be involved.
Last Edited by MindTheGap on Mar 28, 2016 3:34 AM
1847 .... Thats exactly what im looking for. Unfortunately they are no longer available. But i imagine this is the same transformer that's in the inline xfmr. Idk ill buy one n give it a shot.
@mtg. If i had the parts i could figure the rest out. As far as how to fix the socket in. There is a plate on the bottom already that may work if i bore it out a bit. If not ill figure it out.
Re ultimate57. Ofcourse i would LOVE an ultimate. But they are a bit pricey for me at the moment. Surely I'll eventually get a good mic. But as of right now cheaper mics will do the job. They sound pretty darn good, as you know.
Also volume control isn't a huge concern. I just wanted to tinker as you said. And if im in there i might as well add a few thinks.
I was also just interested to know a lil more about what's out there for customizing.
Re phantom power .. some diodes would fix your concerns with phantom frying your elements. Theoretically. ---------- "Trust Those Who Seek The Truth. Doubt Those Who Say They Have Found It."
Last Edited by Killa_Hertz on Mar 28, 2016 4:31 AM
Which Pyle did you find for 13 bucks on Amazon? Was it the PDMIC78? If so, it's a bit more expensive over here, but at just over 21 euros, it still sounds like a deal.
Yes i believe the pylepro PDMIC-78 is what i have. They sound great. Myself, MTG, ShakeyLyman, and a few others use them. They are great for the price.
I recommend you give one a try.
Knock off stuff is hit or miss. More often than not its miss. But this mic is a Hit for sure. ---------- "Trust Those Who Seek The Truth. Doubt Those Who Say They Have Found It."
Last Edited by Killa_Hertz on Mar 28, 2016 5:52 AM
Nice wendell. Didn't think it would be very hard. I assumed i could do just as you did, and use the hole for the cord to fit the jack.
Ive got quite a few dm13s. But one in perticular is VERY nice. Dirty, punchy, but a bit of chrispy highs. That's the one i want "fultimitized" (fake ultimate ized) I love these lil mics. Quite a few of the akai/aiwa models are unbeatable for the money. IMHO. ---------- "Trust Those Who Seek The Truth. Doubt Those Who Say They Have Found It."
Wendell - Ah ha. Very good. I looked around briefly for a socket that would fit, but didn't find a likely one. Now I can go and find one of that type. Thank you!
Yes I agree, they are very good, and light in the hand too.
kHz Re phantom power, I've just been reading up and it appears that the way it's applied means the coil doesn't see the voltage, unless there's a cable fault. I'm not got to press the button, however, to verify this.
Last Edited by MindTheGap on Mar 28, 2016 10:14 AM
Yes, I wish you could just buy an IMT in a box like that. The standard format of the big 1/4" jack is unwieldy and damage prone. Do they come pre-bent? The whole point of the Lo-Z balanced signal is to minimise the length of the unbalanced signal path to minimise noise, so I guess that's why they sell make them in that form.
Maybe another idea for the LW people. The I-Mojo-T?
I know I should just build one, but I couldn't find a transformer in the UK and all the parts add up and I should be practising not soldering.
Hopefully (like Wendell's DM13 revelation!) someone will now tell me you CAN buy them, and here's the link. Please go ahead.
Last Edited by MindTheGap on Mar 29, 2016 4:30 AM
I like the Lone Wolf idea - how about 2 different I-Mojo-T boxes with different kinds of transformers for different tones/amps. Maybe one for tubes, and one for solid state.
the guy in the video is bob heil, he invented the talk box for guitar. joe walsh... rocky mountain way... peter frampton ...do you feel like we do. i have been searching for the transformer he mentions in the video, an xt-1 with no luck. it seems it was like $45.00 dollars if you can find one. but would fit inside the mic.
just got a responce.... Bob, We do still offer the XT-1 transformer at $18 plus shipping. If you would like to place an order please call our service department at 618-257-3000 or if you have a local Heil dealer they may have them on hand.
Excellent. Now I have the XT-1 name I found it in the UK. It's called the HEIL XT-1 on these sites.
But then thinking about it, I should have realised that a passive DI box in reverse should do what I want - i.e. an outboard IMT in a 'pedal' format. Like this one. It even has a handy circuit diagram on the top. d'Oh.
I wonder how well the Heil XT-1 compairs to the one Greg sells, tone wise. Dr Heil's xformer has a wide freq. range and is high quality. Maybe we need a transformer that is not so clean. Hmm, sounds interesting. Good work Bob...BN
ok lets see if i have this right. the 57 has a low impedance transformer , by adding an inline matching transformer you are in" effect" creating dual impendence. this would create a very small loss of signal. not a big deal, that is what i use on my 57, i found one at radio shack. very simple solution. it works great.
the heil transformer if i am not mistaken will fit inside of the mic. so removing the factory one and replacing it should allow a slightly wider freq. response, which is a good thing.
At eighteen dollars i would not hesitate to install the heil xt, however i almost never use the 57 i have it for back up. if i need a stick mic. i am more likely to use my 633 as it is already high impedance, i just plug a guitar cord into it and i am good to go.
The XT-1 in the remote box, which would be located at the amp would give you the best of both worlds. The mic and cable would be low impedance which gives less signal loss and improved high end over long cables. Then the box converts your mic output to high impedance which matches your amp input requirements. This is the same setup as the RS imp xformer but using a higher quality xformer, plus a short cord from the box to amp is less damaging to the amp jack. I like it...BN
Last Edited by Barley Nectar on Apr 02, 2016 8:19 AM
A third option, which to date nobody I know has tried, is to build an external transformer box using a Sowter, Lundahl or other. This would bring the mic back into spec, but with a transformer of a much higher quality. Maybe build a switching box with more than one tranny in it and... hmmm. So there it is, my favorite sort of thing: simple, cheap, and very little to buy or do. And you get a really good mic out of it.
Got my Pyle PDMIC 78 - this thing is fun. It's raspier than the 57, and I swear it has more bottom end. Here it is with my new budget set-up: Pyle mic, solid state Marshall with 6" speaker, and purple XLR cable - who says you can't have a little color in your life?
Great song - is it a solid state amp? The re-amp box helps get a good sound from solid state. Of course, I'm going for that Billy Branch sound - more clean than dirty.
Not a bad mic for around $10 huh? I like it better than the real 57 myself. As you said it seems to have more bottom and rasp. I suppose it depends what you're sound of choice is, but for me ... i love it.
And im always close to the amp. So i think imma try that heil xfmr mod. W/ VC and 1/4" ----------
@Killa I'm sold - I'm gonna stick with it. Obviously, the little amp in my video has no low end, but it's a fun rig to mess around with. But, I'm looking foward to trying the Pyle with a 8" or 10" amp.
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