The 640 had a fairly short run of about 4 or 5 years and was slightly more expensive than your typical dynamic mic. This mic was no longer working so it made a great candidate for the lamp mod. This is a 1940's era Electro Voice 640 dynamic microphone.
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You are looking at a highly collectible 1940's era Electro Voice V-1 "Velocity" Ribbon microphone in working condition. A smaller ribbon mic made by E.V and certainly one of the most unique. This model was widely produced by Electro Voice during the 1940's but was discontinued with the 2nd generation E.V 423A model starting in the 1950's.
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Pic # 2 is from an old E.V catalog showing the 641 and 638 model and it's characteristics. This 638 has a high impedance setting with a very strong 100% signal. It's omni-directional as well picking up a little more background than a uni-directional mic.
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As you can see in the pictures provided this 915 mic is in very good original condition with typical lite wear. It's free of dents or corrosion. The white inner screen is decent but you can see there is a hole a small stain.
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This is the Electro Voice 926 model crystal microphone which closely resembles the E.V 623 model. I don't know the model # that Knight gave this microphone as there is very little info on them. It should be noted that this 926 like most of that era no longer works.
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A smaller ribbon mic made by E.V and certainly one of the most unique. The E.V label looks pretty damn nice too. The V-1 sits on it's original yoke / swivel and it works nicely allowing just the right amount of tension and desired angle.
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This microphone closely resembles the more common 630 model. I have only ever personally seen one other example of these 612 mics before. I believe they were only sold for a couple years as I have never seen them listed in any other E.V catalog except the one I have from 1946.
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Pic # 2 is from an old E.V catalog showing the 641 and 638 model and it's characteristics. This is why I'm including the on / off adapter. This 638 has a high impedance setting with a very strong 100% signal.
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