Ribbon Mic Dissection Pictures

[Rob Flinn]

Stewart

My grampians are definately 50 ohms. Somewhere in this dump I call an office I have the user manual/sheet, if your interested I can spend hours sifting through all this rubbish & send you a copy.

 

[zebra50]

Hi Rob,
I'd love to see the data sheet, but don't spend hours on it - wait till it emerges. I sympathise - one of my colleagues says that my desk has 'strata'!
Stewart

...reslo pix soon....

 

[zebra50]

Reslo Pencil Ribbon Mic...

Picked this up for a tenner, including stand, about 15 years ago now. I was just getting into recording on a four track tascam 244, and thought this mic was a big disappointment because it was so quiet (I was a fool!)... I've seen them fetch over 120 quid on ebay recently. Don't pay that much!

..I really wanted a shure sm58, but that was well beyond budget at the time - I was maybe 16 or 17. Three horseshoe magnets round the back, and lots of the yellow foam again. This is much less figure-of-eight than many ribbon mics.

Plastic surround again (like the grampian), and a mesh to protect the ribbon.

One of my early re-ribboning attempts - big gaps between the magnets and ribbon.

:wink:

 

[soundguy]

man, I bet if you take that mesh out of there you could probably get a better HF response, no? Id go with a second layer of thin mesh on the grill before doing that....

dave

 

[Marik]

I am travelling and don't have a regular access to internet.
Thanks for sharing all these cool pics. I've never had chance to see EMI naked--very cool and very smart design. The triangular shape of pole pieces helps to maintain good efficiency and more uniform flux, while holes help for extended HF response. When I get back I will try to contribute with posting pics of some other mics.

[quote author="adrianh"]

Marik now it your time to shine...... c l o n e[/quote]


I don't think it is actually a good idea for many reasons:
1) It is amazing how much acoustical arrangement of the ribbon mics determines their sound. At the time, manufacturers were forced to use lower efficiency magnets, which were much bigger--it is not the best from acoustical stand point.
2) It is very hard to find magnets of the same size and shape as originals, otherwise the sound will be different.
3) If at the time RCA or other companies had modern Neodymium magnets, I am sure the mics would be completely different, and I believe with using these magnets it is possible to make a ribbon mic with better HF response, but still with good LF response and high output.

 

[Guest]

I just want to say thanks for the pictures and great information all of you provide. I love this stuff.

 

[zebra50]

Cheers! I like taking the photos.

I plan to put these pictures together into a webpage when I get time.

Larry - do you mind if use your pictures too for this?

 

[Rob Flinn]

Its interesting that many of you are enthusing about the EMI design.

In my opinion this mic looks much better than it sounds. The one I had which was in absulutely mint condition was quite dull to listen to, & most of the Reslo`s that I`ve used sounded much better. I think this was a consumer level mic & not really in the same class as some of the Marconi & HMV studio mics. Has anyone ever seen any Abbey Rd pictures that these mics feature in? I haven`t !

 

[SilverhammerNZ]

You're right Rob, that mic was never at Abbey Rd, I spoke once to someone that worked at Abbey Rd and was familiar with the EMI mic, he assured me it was only ever a domestic mic.

It suprised me that the mic has such detail as precise ribbon adjusting set screws and what seems to be a well thought out magnet design, that initially fooled me into thinking it must have been a pro mic.

I've since seen the spec, (see further back up this thread for link) and the mic only does 10k tops. I have re ribboned it several times to try and get the best from it but never succeeded.

I have the new Nady ribbon (chinese made I think), now that's not a bad ribbon mic at all, good tops (15k). large ribbon with modern magnet design.

Larry

 

[Marik]

[quote author="SilverhammerNZ"]
I have the new Nady ribbon (chinese made I think), now that's not a bad ribbon mic at all, good tops (15k). large ribbon with modern magnet design.

Larry[/quote]

Naked pics, pleeeease!

 

[SilverhammerNZ]

Thought that might happen! I'm a little nervous in case the Nady mafia come after me for disclosing industrial secrets.

Actually I have already taken an inside pic but it's hard to see detail because there is a screen each side of the big 2" ribbon and I don't want to open that up. What you can see is that the magnet is modern material, it's thin, plated and shaped in a sort of "U". Apart from that nothing revolutionary about it. They state the ribbon is 2micron.

Larry

 

[CJ]

Excuse my lameness, but those ribbons look like corogated cardboard. Are there ripples in the ribbon or am I on crack?
cj

 

[zebra50]

Well, CJ, you might be on crack for all I know :shock: but your eyes do not deceive you.

The ribbons are corrugated to give them lateral stiffness so they rock don't roll. Seems to be different ways to achieve this - sometimes they look, in section like a triangle wave, other times more like a square wave.

Am I making sense (or am I on crack too?)

 

[ikiru]

Just found this today:

http://answers.google.com/answers/threadview?id=362221
It is about a source for ribbon material....

 

[zebra50]

I have always used Advent research materials for my foil. But they are not cheap. However, a little foil goes a long way.

www.advent-rm.com

 

[SilverhammerNZ]

Yes that Google stuff has recently appeared. The originator paid $100 for the info and now it's all over the web. That's life I guess.

I have been testing some of this material, so far I haven't had a lot of success, some suppliers have 91% pure and others %99.9 (expensive like $125 a sheet.)

I actually don't know which source my material came from but it's the same two thicknesses 1.8 and 2 microns. I am getting it third hand.

Maybe my sample isn't pure enough, either way I can't get it to respond as good as the leaf I have been using. I know the leaf is thinner therefore more sensitive but we're talking a big difference. I'm continuing this exercise with different mics to see if I get a difference. Just tried a MC500 beyer with new material, not much luck.

And yet the ribbons in Royers and the new Nady look like similar material (bright and around 2 microns.) As I said earlier, I wonder about purity.

Zebra's post just popped up while I was writing this, how have you found this material??


Larry

 

[ikiru]

Larry, It seems the reason that none of these foils are successful is the lack of cold forging. I recall scott dorsey saying something to this effect, also I remember reading on your site that the bbc pounded the material they used. Is anyone here a gilder? anyone have a rolling mill??
here is a page about japanese leaf making methods:

http://www.kougei.or.jp/english/crafts/1503/d1503-5.html


-jay

 

[SilverhammerNZ]

Yes, possibly an important factor, I tried beating some of the new sample I have, sandwiched between lots of toilet paper. Can't say I made much difference to it, but I can also say I wasn't very scientific about it I just gave it a few whacks until I had taken the shine off it.

Annealing is another process which may help. Taking the "spring" out of the metal by heating it up then suddenly cooling. Hard to do as you usually end up frying the small thin ribbon. I used to lay it on the stove top. I recall I did get a difference this way, but I was using foil from a capacitor at the time. Haven't tried it recently, maybe I should.

Larry

 

[Guest]

I thought I would try to find a good candidate for ribbons among the various guilding leaf materials. I got several different aluminum leaf brands, copper leaf of various sorts and real gold leaf (double thick).

The double thick gold leaf turns to powder when I even look at it hard. I tried to cut the aluminum but I am in the midst of an arthritis episode and can not get my hands to manage it yet. My niece said she would cut it for me when she visits next (in a month or so).

I don't know if the copper leaf would be as good as aluminum for a ribbon but it is worth a try i guess. Any oppinions on this?

By the way, I finished the prototype of my ribbon mike except for the ribbon. Like a fish out of water, it sits on a shelf waiting for my next move. I havent taken any pictures because it seemed sort of useless to do until I know if it even works.

 

[CJ]

So do you guys put those bends in yourself, or does the material come like that?
And how do you fvigure out what tension to use?
I'm off the hubba rock, by the way.
Those jumbos were kiling me!
(East Palo Alto is about a block away)
:razz: