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Gear / Technical Help => Microphones & Setup => Topic started by: H₂O on May 06, 2008, 07:44:38 PM
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Just seeing if anyone here (i.e. D. Satz) would have an idea as to why the M222 has a +60v versus +120V on older AC701k mics such as the M221b?
Does the M222 use a slightly different version of the AC701? Does the M222 use a circuit to double the voltage to +120V internally?
Could the different versions of the M222 have different voltage requirements?
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The difference is that the M222 utilizes a transformerless design while the M221 had an output transformer. The polarization voltage used to be 120V and now it is 60v based on the different circuitry involved. the official stance is that there is no advantage to one vs the other(polarization voltage wise...when you start talking about TL vs transformer designs, there are many advantages to the former).
The AC701 is not the only tube(there is a list somewhere on one of the newsgroups, I forget which one, maybe rec.audio.tubes??) that can be used with the M222, and so yes, the heating voltages will vary.
addendum: and this is just FYI..there is an adapter somewhere that allows one to use the modern capsules with the old amplifiers.
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There were three types of M 221. The polarization voltage was 60 Volts in the earliest models (designated either as M 221 or M 221 A--though to my knowledge they aren't different), while in the "B" type it was generally 120.
Many years after production had stopped, the U.S. distributor asked Schoeps to assemble a few more M 221 B amplifiers from some of their remaining spare parts, and I've been told that these few amplifiers use 60 Volt polarization, but if so, I don't know why.
Despite the name, the M 222 wasn't intended to re-create the M 221; it's a distinctly different design, and as you've noticed it requires its own power supply and cable. Yes, it's transformerless, which is very nice for high-SPL recording, but most importantly it uses Colette-series capsules and accessories rather than those of the M 221 series. That accounts for the main difference in the sound quality since Schoeps revises their capsule designs from time to time; a capsule of one given type from 1960 or 1970 won't sound exactly like a capsule of the "same" model made in more recent years, even apart from issues of aging and stress during use. Also, you can use active cables, tubes or goosenecks (geeseneck?) with it, which is impossible with the M 221 series.
--best regards
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there was also the Schoeps 221F , the Schoeps 221BH(RF Rejection), and the Schoeps 221 made for telefunken. The F and BH had different connectors(F with the Sogie Plug for French Radio, BH with a larger diameter Tuchel connector)
http://www.mikrofonbau.de/m221_e.htm#sprungmarke431
There were three types of M 221. The polarization voltage was 60 Volts in the earliest models (designated either as M 221 or M 221 A--though to my knowledge they aren't different), while in the "B" type it was generally 120.
Many years after production had stopped, the U.S. distributor asked Schoeps to assemble a few more M 221 B amplifiers from some of their remaining spare parts, and I've been told that these few amplifiers use 60 Volt polarization, but if so, I don't know why.
Despite the name, the M 222 wasn't intended to re-create the M 221; it's a distinctly different design, and as you've noticed it requires its own power supply and cable. Yes, it's transformerless, which is very nice for high-SPL recording, but most importantly it uses Colette-series capsules and accessories rather than those of the M 221 series. That accounts for the main difference in the sound quality since Schoeps revises their capsule designs from time to time; a capsule of one given type from 1960 or 1970 won't sound exactly like a capsule of the "same" model made in more recent years, even apart from issues of aging and stress during use. Also, you can use active cables, tubes or goosenecks (geeseneck?) with it, which is impossible with the M 221 series.
--best regards
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+T - Thanks for all of your input
Would it be possible to power a M222 off a M221b PS that runs 120V if the voltage is lowered to 60V on the power supply?
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I kinda doubt it, but why don't you send an email message to mailbox@schoeps.de and ask Bernhard Vollmer about it directly? He's a good guy and he writes passable English (better than my German).
--best regards
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Yes, it would work in theory, but it isnt very safe, per Bernhard.
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Does anyone have any info on the 'newer' tubes being used in the m222, the first m222s had the telefunken ac701k tubes, heard they changed tubes recently on the m222s...