Modifications
- Neumann Gefell CMV563 and UM57 (Electronics) |
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Neumann
Gefell CMV563 and UM57, conversion to Neumann U47 electronics |
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The
CMV563 and UM57 are fantastic microphones and can still be found at
sensible prices.
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The
CMV563 will normally be found with, at least, the M7
or M7s "Cardioid" capsule. Ideally it should have the M55k
"Omni", M8 or M8s "Fig' 8" and M9 or M9s "Small
Diaphragm Omni" capsules also. Whereas
the UM57
uses the M7 capsule as standard. The M7 capsule being that used by the
Famous Neumann U47 microphone.
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Both
the CMV563 and UM57 microphones lend
themselves to a very effective modification i.e. To convert the
electronics to that used in the legendary U47. The only component not
being changed, being the out-put matching transformer. This being due to
the lack of space within the microphone body.
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UM57
(Upper) and CMV563 with M7s capsule (Lower) |
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The
modification uses the "Missing Link" ML-1955 Low Noise Pentode,
as used in the RV-14m valve assembly. The later being a direct replacement
for the "Telefunken" VF14m.
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After
modification, the "Self Noise" is considerably less than that of
a "Standard" CMV563 or UM57.
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Both
the
"Modified" CMV563, with the M7 capsule fitted and the UM57, will
"Basically" sound like a U47. However, due to the fact that the
CMV563 / UM57 still uses
the original out-put matching transformer, the sound quality will be
"Somewhat" different to that of a U47 i.e. Very close, but not exactly
the same.
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Alas,
there is insufficient space to fit a genuine U47 type out-put matching
transformer inside the CMV563 or UM57 microphone assembly. However, the
final results are very impressive. See Customer
Feedback
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Inside
a CMV563, before and after modification |
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The
associated power supply, N61 or UN61, will also require a complete rebuild.
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Inside
the Neumann U47 and U48, a large wire-wound resistor
is used to drop the HT
voltage, to that suitable for the valve heater. This being one of the
reasons why a U47 or U48 runs so warm. Again, there is insufficient space in either the
CMV563 or UM57 to allow the fitting of such a resistor, therefore this
component is fitted within the associated power supply unit.
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Price, please contact
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Note
- The price quoted covers the cost of "Modifying" the electronics of
the microphone and PSU.
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If
the Capsule / Out-put Matching transformer / Tag Board / Lead (Including some types of
Connectors) are Non-Standard or
Faulty, then additional charges will be incurred.
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"Modified"
N61 power supply, with additional ventilation |
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Customer
Feedback
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".....
I really don’t know what to say. ..... The CMV563 that you
converted is breathtaking ....."
Dermot
Rooney
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"..... you did the
modification on my Neumann Geffell UM57 ..... how
thrilled I am with the results. We have only
recorded vocals with it as yet, but very wonderful
it sounds on this simple but vitally important
task. Sweet and silky high frequencies, solid
warmth and really delightful subtle compression
from the valve. I remember the mic' sounding good
before but now it sounds as if it has lost nothing
of its former magic but gained an expensive and
classy sounding quality."
Martin
Turner, Wishbone Ash
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