Does anybody knows which tube used in old
NEUMAN U47, or someone have idea to replaced with
some modern tube or Fet.
regards zeoN_Rider
NEUMAN U47, or someone have idea to replaced with
some modern tube or Fet.
regards zeoN_Rider
Those Neumann mics used a VF14 originally. They are expensive if you can find one. The better ones were the VF14M which were supposedly hand picked for lower microphonics. Its similar to the EF14 only with a different heater voltage.
Dave
Dave
Yeah, VF14 in triode mode. Good luck finding one of those! Other mics used an AC701 submini... good luck finding one of those too. They had one model, the U67, that used an EF86, which is the only of their tube choices that is still available.
I have seen people use different subs in the u47: 13CW4, EF814,EF14 etc. But they all sound a bit different.
I have seen people use different subs in the u47: 13CW4, EF814,EF14 etc. But they all sound a bit different.
Yes, but not without GREATLY de-valueing the microphone
I dare to speak Heresey! There is a bunch of tubes you could use but the mod is major; socket and tube and some way to shock mount it. The 6au6wa would work. Sony uses it in their condenser mics.It's been used as a cathode follower and as a grounded cathode with great results.
I dare to speak Heresey! There is a bunch of tubes you could use but the mod is major; socket and tube and some way to shock mount it. The 6au6wa would work. Sony uses it in their condenser mics.It's been used as a cathode follower and as a grounded cathode with great results.
people are catching onto the 6au6 as a good tube... very linear in triode mode. There are some new ribbon mics out there that use it as well. That Sony mic (the 800 IIRC) used a triode strapped 6au6 with a special cooling circuit , as well as running the tube with voltage-starved filaments.
A friend had a U47 back in circa 1970. At that time he purchased a "FET replacement kit" from Neumann to have on hand just in case the tube died. Don't know if he ever retrofitted it.
Hi All !
Forget "Tube" .
Lets make oldie with new hard .
For me tube is a steam engine forget , it is 21 s.
By the way Marry Cristmas !
Regards zeoN_Rider
Forget "Tube" .
Lets make oldie with new hard .
For me tube is a steam engine forget , it is 21 s.
By the way Marry Cristmas !
Regards zeoN_Rider
Re: Hi All !
BUT, with anything other than an out-dated and obsolete Tube in one of these mics, it will sound Different.....
These mics have a particular following. If its changed from a tube, it becomes severely de-valued and performs differently...
Just like putting the engine from a 2006 Jaguar into a 1966 Ferrari....
It may perform the same ON PAPER, but it just aint the same, and severely de-valued....
For a replacement, you could try one of the Russian Nuvistors.....The 6C51HB which is equal approx to a 7586, but the Russian tube is MUCH less Michrophonic, and has wire-ended leads whch could be an advantage, as no socket is needed, although its gain may be a little lower than the VF14....
zeonrider said:
BUT, with anything other than an out-dated and obsolete Tube in one of these mics, it will sound Different.....
These mics have a particular following. If its changed from a tube, it becomes severely de-valued and performs differently...
Just like putting the engine from a 2006 Jaguar into a 1966 Ferrari....
It may perform the same ON PAPER, but it just aint the same, and severely de-valued....
For a replacement, you could try one of the Russian Nuvistors.....The 6C51HB which is equal approx to a 7586, but the Russian tube is MUCH less Michrophonic, and has wire-ended leads whch could be an advantage, as no socket is needed, although its gain may be a little lower than the VF14....
I disagree that a "tube" is a steam engine
Yes,it's an antiquated device but your choice is limited. It would take a PhD audio engineer about 300 man hours to come up with a rather complicated 24 FET-transistor circuit and another year to perfect it and it still would not have the headroom and swing the same output voltage that one small vacumn tube can provide. And you would have to match transistors within a fine precision. This is why many recording artists insist on a electron tube condenser microphone and explains their dominance in recording studios. Barbara Streisand won't record wihout her AKG C12A. Johnny Mathis won't record without his Neumann M49. What ever you do don't bastardize this fine microphone. You would make it a Eunuch! You wouldn't put a Chrysler Hemi in a Ferrari. Ray Hughes
Yes,it's an antiquated device but your choice is limited. It would take a PhD audio engineer about 300 man hours to come up with a rather complicated 24 FET-transistor circuit and another year to perfect it and it still would not have the headroom and swing the same output voltage that one small vacumn tube can provide. And you would have to match transistors within a fine precision. This is why many recording artists insist on a electron tube condenser microphone and explains their dominance in recording studios. Barbara Streisand won't record wihout her AKG C12A. Johnny Mathis won't record without his Neumann M49. What ever you do don't bastardize this fine microphone. You would make it a Eunuch! You wouldn't put a Chrysler Hemi in a Ferrari. Ray Hughes
not to 'jack but the V10 OHV truck engine in the real Viper GTS (don't even mention that new crap) seems pretty badass to me 🙂
Alastair E: Be careful about substituting tubes for the VF14 in a Neumann mic. The VF14 uses a 40 volt filament. The replacement kit supplied by Gotham Audio 30+ years ago used a 13CW4 nuvistor with a different filament voltage dropping resistor in a plug in assembly. The 7586 WILL NOT WORK and you may instantly destroy a 7586 or other tube with a low voltage heater. The 6AU6 heater current is excessive for the Neumann NG supply. You should look at the 407A 9 pin miniature dual triode with the sections in parallel and the heater sections in series. The heater voltage with the sections in series is on the order of 40 volts which is compatable with the VF14 heater. The 407A was used in old telephone repeaters and other low noise applications and you should be successful building a tube replacement on a piece of bakelite or plexiglass with pins arranged to fit the VF14 socket. The "homebrew" plug in retrofit is necessary since mods made to the mic itself devalues it substantially.
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