Microphone ribbon material
I am looking for a source of high quality pure aluminum foil or leaf that is in the
thickness range of 1.8 to 2.5 microns. This is used in a ribbon
microphone element. The material comes in sheets and is not the
aluminum leaf sold by art supply stores. The aluminum thickness must
be precise. I am willing to pay $100 for
the name of a good source. |
Request for Question Clarification by
umiat-ga
on
16 Jun 2004 19:05 PDT
Can you give us any idea what brand of microphone you are using the
ribbon in? It may make the research for a supplier a bit easier. Have
you bought such ribbon before from a store that went out of business,
or is the first time you are looking for a source to replace it?
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Clarification of Question by
dave100-ga
on
16 Jun 2004 19:17 PDT
I have not purchased this material before although I have spoken with
Alcoa and they do not have it. Some microphones that use ribbon
materials of this kind appear to include AEA/Forensic audio(US) Royer
Labs (US), Coles (UK) and Nady(US?). I have been told that one
manufacturer supplies this material in sheets approximately 10" x 10".
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Request for Question Clarification by
umiat-ga
on
16 Jun 2004 19:48 PDT
dave,
Please take a look at this article:
http://www.lkmusic.co.nz/ribbonfix.htm
If you click on the link for the online supplier, it brings you to an
art supply store, which you have said you don't want. There is no
micron thickness listed on the site, so I would have to call them.
Another supplier mentioned in the article above is Houston Arts, and
you can see their leafing here:
http://www.houstonart.com/metalleaf.asp. Again, there are no thicknesses listed.
Do any of these look remotely similar to what you are seeking? And
when you say you need the thickness in the "range of 1.8 to 2.5
microns" does that mean any thickness between that range is
acceptable?
Also, this is likely going to entail several long-distance phone
calls so your question price should take that into account.
(Researcher's only get 75% of the price of the question, so numerous
long-distance calls may be out of line)
Anyway, look at the two sources and see if the leaf "looks" like what
you require, aside from not knowing the thickness at this point.
umiat
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Request for Question Clarification by
umiat-ga
on
16 Jun 2004 22:45 PDT
If Royer Labs uses these kinds of ribbons, would you consider simply
buying the replacement ribbon from them?
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Clarification of Question by
dave100-ga
on
17 Jun 2004 08:19 PDT
I did look at lkmusic.co.nz and we have discussed supply of this
material before with the site owner, but we have no answer to the
question. The art store materials mentioned on the site do not have
the quality or consistency we need and that is assumed ot be used by
other critical applications such as microphones. Houston Art is the
art supply store manufacturer as you correctly state. The thickness
range given is a range of acceptable thicknesses as long as the
thickness is known and consistent - unfortunately not the case with
the Houston Art materials. We are looking for the materials that are
used for the ribbons in ribbon microphones, but we are not repairing
these mics. We had been informed that the material is shown on a
microphone site in the 10" X 10" sheets - this suggests to us that
such a supply is available, from somewhere. Our application would
require many fairly large pieces at least 2" long which is longer than
their replacement ribbons to my knowledge. I ended up in the same
place you have after a few minutes using search terms foil, ribbon,
microphone, leaf, micron. What is the appropriate payment? I selected
$100 for this anser, I see that the suggested range is up to $200
which would be ok if we can nail the source. Dave100
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Request for Question Clarification by
smudgy-ga
on
17 Jun 2004 09:27 PDT
Hi dave100,
Could you give me some idea of what the permissible tolerances on the
leaf would be? I'd like to get a sense of level of purity and
variation in thickness in particular. If, say, I were able to find
2-micron aluminum leaf, by how much could the thickness vary to still
suit your needs? .1 micron? Less? Any information of this sort would
be helpful.
Thanks,
smudgy.
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Clarification of Question by
dave100-ga
on
17 Jun 2004 09:56 PDT
Smudgy
I think that the instruments we have available can only resolve down
to about 0.1 micron or so, which means that an actual two sided
tolerance, for practical purposes, would be about 0.3 micron. I am
not sure what the state of the art allows. Certain scientific foils in
small disks that that are like pellicles are listed in various places
- these are extremely precise, pinhole free, but also very expensive
and probably not the sheet form we need. They are used for high vacuum
applications and produced, I think, by sputtering aluminum. We do not
particularly care about porosity or minute pinholes. "Pure" aluminum
is 99% or better for practical purposes. If there happens to be foils
in an alloy such as Duralumin, which has a higher tensile strength, in
the dimensions we need, that might be a practical substitute material.
Dave100
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Request for Question Clarification by
smudgy-ga
on
17 Jun 2004 10:30 PDT
Hi dave100,
I have found the following item, though I will search for others to
see if I can find you a variety of suppliers. Please let me know,
though, if this will suit your needs, so that I know if I'm on the
right track:
Aluminum foil, 2.0 micron thickness, available in 50mm x 50mm and
100mm x 100mm sizes, 99.1% purity, not guaranteed pinhole free.
There are other foils in micron thicknesses available from the same
supplier, but this is the only one so far that falls within your
parameters.
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Clarification of Question by
dave100-ga
on
17 Jun 2004 12:10 PDT
smudgy
The 100mm square 2 micron material may indeed be suitable for our
application. You appear to be on the right track and this is
encouraging. Dave100
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