Tube LDC’s: How Important is the Tube/Valve?

[gmel555]

I’m in the final stages of deciding on a Pearlman LDC. Regardless of whether or not Pearlman is “the one”, I seem to face perhaps yet another decision point…. which tube/valve? It seems one can go down quite a tube rabbit hole. My own experience w tube LDCs is limited to what I’ve read and heard on demos, but experience w tubes in guitar amps tells me they can make a real diff. My impression is diff tubes in the same mic can move the “needle” towards (or away)from more warmth, make it more natural or more colored, etc. My post performance processing experience is somewhat limited so my goal is to make recordings that require only post recording tweaking. This leads me to believe the closer my mic’s output is to what I want to better (that’s probably not an unusual goal). With Pearlman there are options for NOS Tekefunken GF metal jacket tubes, which require diff wiring/sockets than other modern tubes, so a “go/no go” decision on GF has longer term considerations. I currently have options to go in either direction for about the same cost. So…..generally speaking how important should tube “considerations” be when selecting a microphone, either when buying or even when pulling a mic out of ur locker? (Assume any tube considered must meet an acceptable threshold of quality/suitability for a given mic)

[jim1960]

Bad tubes can introduce a lot of noise and you really don't want that. That said, you can get a bad tube in any batch, even among highly coveted tubes like the NOS Telefunken VF14, which can cost upwards of $3k for one that is tested and deemed microphonic by a reliable source, you will find duds that are just too noisy for microphone use.

But if you're buying the tube upgrade from Pearlman, I'm going to assume he has tested the tubes he's selling or at least will burn it in your microphone and test it that way. Dave Pearlman has a very good reputation and his customer service is also very good.

I have no idea what tube options you have or even which microphone you're considering, but a friend of mine recently purchased a used TM-1 that Dave Pearlman modified from his original design in two ways...
First, he installed a Neumann Capsule.
Second, the mic has a NOS Telefunken EF14 tube (a much more affordable option than the VF14). I've sung into that mic and it comes VERY close to my Flea 47. While the capsule is important, I don't think Dave makes bad capsules. I suspect most of the magic is coming from that EF14 tube.

If the TM-1 is the mic you're interested in, you can ask Dave about my friend's mic. It was in Dave's shop a month or two back. My buddy's name is Vincent Ricciardi. Dave will likely remember. But yeah, a NOS Telefunken EF14 would be my pick for a TM-1.

[gmel555]

Originally Posted by jim1960

.....I have no idea what tube options you have or even which microphone you're considering, but a friend of mine recently purchased a used TM-1 that Dave Pearlman modified from his original design in two ways...
First, he installed a Neumann Capsule.
Second, the mic has a NOS Telefunken EF14 tube (a much more affordable option than the VF14). I've sung into that mic and it comes VERY close to my Flea 47. While the capsule is important, I don't think Dave makes bad capsules. I suspect most of the magic is coming from that EF14 tube.......

Thx, Jim. I didn't give more detail originally as my post was already kinda long and I was asking more from a generic standpoint, as in: "Am I the only obsessive who spends more than 5 minutes thinking about which tube option I should get?" So WTS, I am considering either a TM-1 or TM-47. The TM-47 current standard tube is a 6SJ7 or 6AC7, with special orders possible for NOS Telefunken EF12 or EF14, at add'l cost. (I imagine I could order a TM-1 w an EF tube as well.) The EF's require different wiring and pin sockets, which renders them only suitable for future tube changeouts with similar EF tubes (unless modded back for std tubes). Your experience with an EF14 loaded TM-1 is VERY interesting/useful. I've heard demos of TM-1 (stock capsules), one had an EF14 and most others had the "std" tube. Both were quite good, but it was the EF14 loaded mic that REALLY knocked my socks off. You've answered my original question AND added a corroborating data point on the EF14

[DupleMeter]

In general the tube makes a big difference. 2nd only to the capsule.

The EF14 is a superb tube for a mic. I seriously considered a Pearlman, but ended up going with Signal Arts to get the vintage M7 capsule & that specific sound of the early u47/m49.

And, not to burst your bubble, but without a superb recording space, a top notch signal chain & experience/skill as an engineer, the likelihood of not needed post processing on a recording is unrealistic. You’re expecting a nice mic to make you Al Schmidt.

[gmel555]

Originally Posted by DupleMeter

In general the tube makes a big difference. 2nd only to the capsule.

The EF14 is a superb tube for a mic.

And, not to burst your bubble, but without a superb recording space, a top notch signal chain & experience/skill as an engineer, the likelihood of not needed post processing on a recording is unrealistic..

Thx for confirming comments above, that’s very helpul👍. and no worries, no bubble bursted; I didn’t say zero processing, but probably did overstate my meaning there.. (I’ve got a very good recording space as well and have gotten results I happy with for years, but have never had a tube mic before and hope I’ll be even “happier”

[DupleMeter]

Originally Posted by gmel555

Thx for confirming comments above, that’s very helpul👍. and no worries, no bubble bursted; I didn’t say zero processing, but probably did overstate my meaning there.. (I’ve got a very good recording space as well and have gotten results I happy with for years, but have never had a tube mic before and hope I’ll be even “happier”

Cool.

Not to muddy the waters, but if I were going to get a single tube mic for acoustic guitar I'd probably look at a C12 or ELAM 251 before a U47. The 47 style mics can be too mid aggressive in a very unpleasant way on many acoustic guitars.

I would also check on the cost of replacement tubes for any mic you consider, as many of the classic tubes (VF14, Nuvistor, etc.) are prohibitively expensive these days (like 3X the cost of the mic). Part of the cost of ownership will be tube replacements over the years. Just be aware of what you're getting into.

[keith.rogers]

Really, just curious, but is tube life (in a microphone) really a concern?

Preamp tubes in this kind of use should last a long, long time. Even in guitar amps that aren't tossed in and out of vans and dropped you can find 60 year old 12ax7s humming along just fine.

Anyway, I'd probably not buy a tube mic that I couldn't return after a trial. And, if you like it, maybe buy a spare tube at that time. Tube factories are pretty rare these days, and located in places that may not exist or be accessible at any point in time. (A factor I thought about when I decided to get rid of the tube mic I had, even though I really liked it. The real pain point though was footprint of the dang thing with heavy stand, preamp box, cabling, eh - too much for my small space and worked against my keeping things set up mode of operation...)

[jim1960]

Originally Posted by DupleMeter

Not to muddy the waters, but if I were going to get a single tube mic for acoustic guitar I'd probably look at a C12 or ELAM 251 before a U47. The 47 style mics can be too mid aggressive in a very unpleasant way on many acoustic guitars.

I don't disagree with the pushed mids on 47-ish mics. But if vocals are also in the mix... well, the U47 isn't revered as the king without reason. There's nothing more important than the vocals in a song. So if my only tube mic is a 47-ish mic, I'll do the extra EQing needed to make the guitars work rather than go in a different direction and take away from the vocals.

Just to be clear, what I said there is from my perspective as someone on whom a 47 sounds better than anything else I've ever tried. Not every mic or mic type works universally well on everyone. Some of us go through a lot of trial and error in our search for what works best on us, but that's part of the fun and it's how we learn. For a long time, my vocal mic was an AKG Solidtube. At some point, someone offered to trade their Blue Kiwi for an Avalon M1 preamp I was selling, so the Kiwi became my main vocal mic for some years. I liked both of those mics but I still felt the vocals could sound better. Some people thought, given my voice, I should get a 47-ish mic. It took me a few years to decide on the mic and make the move, but I eventually landed on the Flea 47 and it was like BOOM! That's what I've been looking for the whole time. I added a couple of mics this year ...a Beesneez BU67 and a Telefunken AR51... which will also be on vocal duties sometimes but the 47 is my main vocal mic and I don't see that changing anytime.

Originally Posted by keith.rogers

Really, just curious, but is tube life (in a microphone) really a concern?

If I was buying a vintage U47 and had no idea how old the tube was, it might be. But if I had $30k+ to drop on a mic, dropping $3k on a tube might not bother me so much as being able to actually find a quality example of a NOS Telefunken VF14.

For my own tube mics, I'm doubtful I'll ever burn out a tube in my lifetime. And unless you're running a commercial studio where the mics are on hours at a time day after day after day, it's probably not something to be too concerned about. In gmel's case, a microphonic NOS Telefunken EF14 from a reputable seller who burns and tests tubes before selling to ensure their microphonic properties, a replacement would run around $300 today. We all have different budgets but for me that wouldn't sway me from ordering a mic with that tube.

[DupleMeter]

Originally Posted by jim1960

I don't disagree with the pushed mids on 47-ish mics. But if vocals are also in the mix... well, the U47 isn't revered as the king without reason. There's nothing more important than the vocals in a song. So if my only tube mic is a 47-ish mic, I'll do the extra EQing needed to make the guitars work rather than go in a different direction and take away from the vocals.

I get that, and the C12 has the exact same reputation for acoustic instruments, which is why I mentioned it.

As far as tubes go. There is no reliable way to predict when a tube will go bad, especially as most high end mics are coming with NOS tubes. They may last 10 years, they may last 10 weeks. You just don't know & should expect to need tubes at some point.

[jim1960]

Originally Posted by DupleMeter

I get that, and the C12 has the exact same reputation for acoustic instruments, which is why I mentioned it.

Just out of curiosity, do you know of a sub-$3k C12 clone that really does come close to the original? I haven't come across one yet so I don't know if it doesn't exist or if I've just missed it somehow.

[gmel555]

Originally Posted by DupleMeter

.....Not to muddy the waters, but if I were going to get a single tube mic for acoustic guitar I'd probably look at a C12 or ELAM 251 before a U47. The 47 style mics can be too mid aggressive in a very unpleasant way on many acoustic guitars.

I would also check on the cost of replacement tubes for any mic you consider....

No problem....I'm not one to post "what should I buy" threads, but always welcome recommendations for things to check-out. The Pearlman or other tube-LDC is primarily for vocals, though I'll check it out for guitar as well. I have other mics (Gefell M930, AEA N22, transformerless SM57, AND currently trading in one set of SDC's for something else (TBD) primarily for recording acoustic guitar...I have guitars from parlor to dread so I usually spend some time matching the guitar to the song and then the mic.

Re tubes, YES...if I go with something vintage like an EFxx, I'd buy & put aside at least one extra, tested replacement. I can swing an extra EF 11/12/14 or two. If never needed, they'll likely appreciate faster than money in the bank anyway. LOL

Originally Posted by jim1960

But if vocals are also in the mix... well, the U47 isn't revered as the king without reason. There's nothing more important than the vocals in a song. So if my only tube mic is a 47-ish mic, I'll do the extra EQing needed to make the guitars work rather than go in a different direction and take away from the vocals.
.....but the 47 is my main vocal mic and I don't see that changing anytime.

YES and this new mic is mainly for vocs....as a vocalist first and guitarist second the vocs are my first concern. At this stage I'm looking for that "one"** vocal mic I can love. (I'm now doing songs for my grandkids, so it's kinda now or never).

**: "THE ONE" sounds like I'm talking guitars now, for which I actually don't believe in "the one"...LOL

[DupleMeter]

Originally Posted by jim1960

Just out of curiosity, do you know of a sub-$3k C12 clone that really does come close to the original? I haven't come across one yet so I don't know if it doesn't exist or if I've just missed it somehow.

Shannon Rhoades was building the best C12 clone, but he’s not currently producing them. If you look around you can find them used. They’re around $1500.

We have one at the studio, it’s a wonderful mic. I go between that & the Signal Art U47. Both beautiful mics in their own right, but very different.

[DupleMeter]

Originally Posted by gmel555

No problem....I'm not one to post "what should I buy" threads, but always welcome recommendations for things to check-out. The Pearlman or other tube-LDC is primarily for vocals, though I'll check it out for guitar as well. I have other mics (Gefell M930, AEA N22, transformerless SM57, AND currently trading in one set of SDC's for something else (TBD) primarily for recording acoustic guitar...I have guitars from parlor to dread so I usually spend some time matching the guitar to the song and then the mic.

Re tubes, YES...if I go with something vintage like an EFxx, I'd buy & put aside at least one extra, tested replacement. I can swing an extra EF 11/12/14 or two. If never needed, they'll likely appreciate faster than money in the bank anyway. LOL


YES and this new mic is mainly for vocs....as a vocalist first and guitarist second the vocs are my first concern. At this stage I'm looking for that "one"** vocal mic I can love. (I'm now doing songs for my grandkids, so it's kinda now or never).

**: "THE ONE" sounds like I'm talking guitars now, for which I actually don't believe in "the one"...LOL

For vocals, yeah a U47 or M49 would be my first choice. If those are too aggressive for the voice, then I’d try a U67 or a ribbon (I really like the AEA R84 on some vocals).

[KevWind]

Originally Posted by gmel555

No problem....I'm not one to post "what should I buy" threads, but always welcome recommendations for things to check-out. The Pearlman or other tube-LDC is primarily for vocals, though I'll check it out for guitar as well. I have other mics (Gefell M930, AEA N22, transformerless SM57, AND currently trading in one set of SDC's for something else (TBD) primarily for recording acoustic guitar...I have guitars from parlor to dread so I usually spend some time matching the guitar to the song and then the mic.

Re tubes, YES...if I go with something vintage like an EFxx, I'd buy & put aside at least one extra, tested replacement. I can swing an extra EF 11/12/14 or two. If never needed, they'll likely appreciate faster than money in the bank anyway. LOL


YES and this new mic is mainly for vocs....as a vocalist first and guitarist second the vocs are my first concern. At this stage I'm looking for that "one"** vocal mic I can love. (I'm now doing songs for my grandkids, so it's kinda now or never).

**: "THE ONE" sounds like I'm talking guitars now, for which I actually don't believe in "the one"...LOL

If I were looking for a 47 type I would seriously consider ADK Z Mod 47 on sale At FRONT END AUDIO
https://www.frontendaudio.com/adk-z-...be-microphone/

I ended up choosing the ADK Z MOD 251 over the 67 Unfortunately the 47 was not available at the time . The 251 which has just a bit more top end and air on it BUT I do have to EQ out some occasional sibilance on my vocals
I honestly would probably be just as happy with the 47 and I am guessing there would less sibilance to EQ

Here is a sample of my 251 on my vocal (Also it came with an additional backup Mullard tube )

[jim1960]

If anyone needs a solid source for microphone tubes, Christian Whitmore (Pro Audio Tubes) has a stellar reputation. He personally tests every tube he sells. He won't be the cheapest seller but the guy knows tubes like few others. He doesn't have a website or a social media presence but if you google his name you'll find people praising him in various audio forums.

Here's a link to one person's reaction after dealing with Christian the first time.

He can be reached via his AOL email address (yeah, that's still around)...
[email protected]