Tube Microphones?

[Robin L]

HiYa kidz!

Couldn't help but notice a few pro audio types in this particular neck of the woods. I'm doing some volunteer work for a local elementary school. I run audio for a Zoom of our assemblies and have done some work recording and playing with this group. When I started recording, some thirty years or so ago, I started with some Schoeps tube small diaphragm condenser microphones, a big mistake. Noisy and unreliable. Later, used a tube Neumann dual large diaphragm condenser microphone, appropriate for MS recording. Didn't like that one either. My favorite small diaphragm condensers are the Klaus Heyne Neumann KM 84s, the closest to an open window into a room I experienced. Back then, it was all classical stuff, the kinds of things audiophiles like to point to as approaching the "absolute sound" though they aren't.

Anyway, a few weeks ago, I'm recording the school band. A friend/former member of the band brings a very recent large diaphragm omni condenser, tube powered. It had none of the issues of the vintage [and doubtless in need of upgrades] tube microphones I worked with before. I can't even tell you the name of the microphone [I'll ask Giles] but compared to the sandpapery upper-mids of our Shure SM 58s, the sound went down like caramel. Very smooth top, low noise, very sweet with female vocals. It's not like I'm rushing out to get me some new microphones [if you want to help, please send money to . . .] but I am intrigued with the effect and wonder if other recordists/engineers/hobbyists favor or disfavor tube microphones.

I don't have a dog in this, am genuinely curious what other recordists have experienced.

 

[DVDdoug]

I'm not a recording engineer but the main difference in "sound quality" between microphones is frequency response. and you can tweak that with EQ. (Of course there are different directional patterns and directional characteristics, noise characteristics, overload characteristics, and different "features" etc.)

I'm NOT a fan of 1950s technology... IMO you can do better with FETs (and other modern electronics) and with a FET mic you don't need a special, bulky, expensive, power supply or special cables & connectors

Recording engineers usually don't want a "flat' microphone. Large Diaphragm Condensers are used for most vocals and almost everything else and in a 'big" recording studio you have lots of mics to choose from for every situation.

There are a couple of software plug-ins that make one mic sound like another (microphone modeling). Antares has one where you type-in the model number of the mic you are using and the one you wish you were using. At least one other company sells their own "standard" mic with software and you tell it which one you wish you were using.

The pro world isn't as goofy as the audiophile world but there is still a lot of mythology... If Frank Sinatra had a hit or won a Grammy with a certain Neumann microphone, then everybody wanted to use it. And in those early days, of course there weren't as many good mics to choose from. Closer to "my day" the rumor got out that Michael Jackson used an SM7B and then everybody wanted to use it (and some people hate it).

 

[MakeMineVinyl]

Most of my tube microphone experience is with the Neumann U67; it was a very smooth microphone but like most all recording microphones had a hump in the 6-8kHz region to give presence to the sound that would be missing if a truly 'flat' microphone were used.

I still have a Bruel & Kjaer tube 1/2" instrumentation microphone which I use occasionally for measurements. I wouldn't ever try recording with it because it's noisy due to the small diaphragm.

The one thing I like about tube microphones, especially the U67 was that the outside always felt warm, which I'm sure warmed up the sound, at least in my mind.

 

[Blumlein 88]

I've used Rode NTK's a bit. They have only a tiny bit of the tube goodness. They are so quiet and flat in response I didn't find it worthwhile vs other good FET's. The disadvantage was having to worry with the extra box which supplied power to the tubes.

 

[Waxx]

They are used for the same reason that tube microphone preamps, tube equilizers and tube compressors/limiters are still used. They colour the sound in a particular way that fits the wanted sound of the engineer. They even make devices that emulate the tapemachine colouring of the sound today just to enchange the sound. The myth that the recording engineer and mixing engineer tries to capture only the performance in the studio may be a persistent one, but it's a myth, the sound is coloured in a lot of ways and the recording should sound good (whatever that is), not true to the source. With classic music that is less the case (they try to stay close to the real sound), but all other music is very coloured while recording and mixing it with tubes, transformers, colouring opamps and so on...

 

[DonH56]

The Shure 57/58 (same capsule, different cap/windscreen) like many vocal mics have a "presence boost" that peaks the upper midrange to help vocals "cut through the mix". Some mics (tube or not) have that, some don't, depends on the intended application. I personally tend to favor large condensers, tube or not, over smaller-diaphragm mics in general but that's as much personal bias as performance. In any event, as said by others, using EQ to flatten the midrange hump will get you a long way towards the "tube" sound you heard based upon my interpretation of your post.

As an aside, why omni? I tended to use the usual cardioid response (or maybe M-S pair, though usually just X-Y since it is easy with a mic crossbar on the stand and less to fiddle with at the board) when recording a band (or anything else) to help reject audience noise and such, unless the mic is hanging in the middle of the band.

On a purely personal note, I have used mostly AKG (C414, then later cheaper C3000/C4000/C1000 mics -- the C1000 is an end-fire condenser) and a few Shure mics (57/58 for rugged stage use, 81 for instruments) over the years (not doing recording now). I never really cared for the sound or price of the Neumanns. A friend had some Rodes that were very nice. I like AEA and Royer ribbons but would not put them on a stage without some thought (and maybe checking my insurance). I have not kept up; there are many inexpensive mics that perform well these days.

FWIWFM - Don

 

[Robin L]

The Shure 57/58 (same capsule, different cap/windscreen) like many vocal mics have a "presence boost" that peaks the upper midrange to help vocals "cut through the mix". Some mics (tube or not) have that, some don't, depends on the intended application. I personally tend to favor large condensers, tube or not, over smaller-diaphragm mics in general but that's as much personal bias as performance. In any event, as said by others, using EQ to flatten the midrange hump will get you a long way towards the "tube" sound you heard based upon my interpretation of your post.

Makes me wish the Alesis mixer I'm using had true parametric controls. On the other hand, that presence boost is pretty useful for coming across in a zoom assembly. We also have Sennheiser [835?], had cheap Behringer cardioid dynamic mikes. There's a small dynamic Sennheiser intended for guitar amps [just drape the front of the mic over the cab's speaker] for mic-ing hand percussion.

As an aside, why omni? I tended to use the usual cardioid response (or maybe M-S pair, though usually just X-Y since it is easy with a mic crossbar on the stand and less to fiddle with at the board) when recording a band (or anything else) to help reject audience noise and such, unless the mic is hanging in the middle of the band.

Giles brought the microphone, that's why. Would have preferred the cardioid option but didn't have it. The singer was close enough to the microphone to properly balance and "sit" in the mix. When I was getting paid for pro audio my default microphones were Neumann 140's and those freaky Octave small diaphragm condenser mics. Audience wasn't an issue with the omni, it was only used for recording.

On a purely personal note, I have used mostly AKG (C414, then later cheaper C3000/C4000/C1000 mics -- the C1000 is an end-fire condenser)

We've got an AKG C1000, what do you think of it? I haven't used it. I recall working with an old pair of AKG 414 microphones, didn't care for them. That might be on account of their age. Microphones do not age well. I also recall working with the AKG 451, found it to have a "steely" coloration, very useful for certain types of guitars but a little harsh for me otherwise.

and a few Shure mics (57/58 for rugged stage use, 81 for instruments) over the years (not doing recording now). I never really cared for the sound or price of the Neumanns. A friend had some Rodes that were very nice. I like AEA and Royer ribbons but would not put them on a stage without some thought (and maybe checking my insurance). I have not kept up; there are many inexpensive mics that perform well these days.

FWIWFM - Don

I did not like the sound of the Neumann 140/130 as much as the original KM 84/83. The Klaus Heyne modified KM 84 was probably the best SDC I used, but the Schoeps Collette series is nearly as fine, albeit with a touch of excessive brightness compared to the customized KM 84.

 

[Waxx]

When i was doing production work, i prefered the AKG C414EB, C12 and C28 and the Microtech Gefell (the old east german neumann branch) UM70 and MV692/M70 over the Neumann microphones in most cases. Especially Microtech Gefell is very underrated down here. But those need to be in good shape to do that. Gefell still makes those new and very close to the original designs (now called UMT70S and M29x series), but the actual AKG versions of those old classics are far from the same as the old ones.

But these days many good microphone brands are availeble, so paying a fortune for old Neumann microphones is a bit foolish. It's probally only marketing for the studio that makes them sell still.

 

[Robin L]

When i was doing production work, i prefered the AKG C414EB, C12 and C28 and the Microtech Gefell (the old east german neumann branch) UM70 and MV692/M70 over the Neumann microphones in most cases. Especially Microtech Gefell is very underrated down here. But those need to be in good shape to do that. Gefell still makes those new and very close to the original designs (now called UMT70S and M29x series), but the actual AKG versions of those old classics are far from the same as the old ones.

But these days many good microphone brands are availeble, so paying a fortune for old Neumann microphones is a bit foolish. It's probally only marketing for the studio that makes them sell still.

I remember finding out that Microtech Gefell was the East German branch of Neumann. I also recall a couple of recording engineers saying that Beyerdynamic large diaphragm microphones were based on Neumann designs, notably this microphone, the Beyerdynamic MC 840, which I was told is practically a U89 but a lot less expensive. I recall liking these a lot:

 

[AnalogSteph]

As an aside, why omni?

Yeah, this. I mean, it can work splendidly for an old-timey folk recording with performers grouped around the mic, but I'd expect the default for a band or choir recording to be a pair of cardioid small-diaphragm condensers in X-Y (SDCs because you're recording around 45° off-axis on average and not that many LDCs have the required evenness of dispersion to pull this off without too much coloration for reasons of aperture size of nothing else... the Shure KSM32 with its smaller-than-average 0.75" = 19 mm diaphragm comes to mind; most pencil condensers use 16 mm capsules, so it's not too far off).
Mind you, both have their own sets of problems. With pencil condensers you have to watch out for the bass response and noise level instead, and their small size means that electronics tend to be more basic and may be susceptible to intermodulation distortion (which can be exposed by a "jangling keys" test).

I recall working with an old pair of AKG 414 microphones, didn't care for them. That might be on account of their age. Microphones do not age well.

Why do you think so? The usual gold-sputtered diaphragms in condensers should be quite resilient, they just need the dust very gently cleaned off every once in a blue moon and should generally be kept dry. There's not overly much to go wrong with the electronics either, the odd dried-out electrolytic after a quarter century possibly excepted. Shouldn't be any worse than any other electronics. Dynamics are even harder to kill, it pretty much takes severe mishandling to ruin them entirely (applying bias voltage across the element due to miswiring, drowning them in salt water, ...). You might have a wire come off internally if they are banged around too much but that's generally fixable.

Quite a few different C414 variants were made over the years, some measure superbly flat like the C414EB, others like the C414B-XLII have substantially more of a "house sound". I don't remember which modern 414s I've heard but they seemed OK, not a major fan of the coloration on the C214 though. (I'm more of an AT2035 - NT1 - MK4 kinda guy.)

I also recall a couple of recording engineers saying that Beyerdynamic large diaphragm microphones were based on Neumann designs, notably this microphone, the Beyerdynamic MC 840, which I was told is practically a U89 but a lot less expensive.

Which, mind you, still was substantially north of 1000€. Arguably fair for a multipattern LDC "made in Germany" but hardly what you would call a bargain. It's another of those more universal types with a slightly smaller-than-average 22 mm diaphragm though, which is a plus. One might consider a Sennheiser MK8 a suitable modern counterpart (~800€ with shockmount), assuming you don't go high-tech with an Austrian Audio OC818 (~1000). Not like there's any shortage of good multipattern LDCs in this price range or anything.

 

[Robin L]

Yeah, this. I mean, it can work splendidly for an old-timey folk recording with performers grouped around the mic, but I'd expect the default for a band or choir recording to be a pair of cardioid small-diaphragm condensers in X-Y (SDCs because you're recording around 45° off-axis on average and not that many LDCs have the required evenness of dispersion to pull this off without too much coloration for reasons of aperture size of nothing else...

The recordings I made of the Lincoln Elementary School band were mic-ed for individual performers, the LDC tube mic on the lead vocalist, but naturally picking up sounds in the background, which resulted in a number of happy accidents. But there was a line-in into the mixer for guitar and bass. I preferred just the omni positioned carefully to capture both Miriam and her mandolin, which sounded better than attempting to cover the mandolin with a pickup or separate microphone.

the Shure KSM32 with its smaller-than-average 0.75" = 19 mm diaphragm comes to mind; most pencil condensers use 16 mm capsules, so it's not too far off).
Mind you, both have their own sets of problems. With pencil condensers you have to watch out for the bass response and noise level instead, and their small size means that electronics tend to be more basic and may be susceptible to intermodulation distortion (which can be exposed by a "jangling keys" test).

Good to know.

Why do you think so? The usual gold-sputtered diaphragms in condensers should be quite resilient, they just need the dust very gently cleaned off every once in a blue moon and should generally be kept dry. There's not overly much to go wrong with the electronics either, the odd dried-out electrolytic after a quarter century possibly excepted. Shouldn't be any worse than any other electronics. Dynamics are even harder to kill, it pretty much takes severe mishandling to ruin them entirely (applying bias voltage across the element due to miswiring, drowning them in salt water, ...). You might have a wire come off internally if they are banged around too much but that's generally fixable.

Quite a few different C414 variants were made over the years, some measure superbly flat like the C414EB, others like the C414B-XLII have substantially more of a "house sound". I don't remember which modern 414s I've heard but they seemed OK, not a major fan of the coloration on the C214 though. (I'm more of an AT2035 - NT1 - MK4 kinda guy.)

I think the microphones I borrowed from KPFA were really beaten up. That includes the Neumann tube stereo microphone. I suspect a good representation of these microphones might change my impression, though I never have been a fan of the AKG house sound.

Which, mind you, still was substantially north of 1000€. Arguably fair for a multipattern LDC "made in Germany" but hardly what you would call a bargain. It's another of those more universal types with a slightly smaller-than-average 22 mm diaphragm though, which is a plus. One might consider a Sennheiser MK8 a suitable modern counterpart (~800€ with shockmount), assuming you don't go high-tech with an Austrian Audio OC818 (~1000). Not like there's any shortage of good multipattern LDCs in this price range or anything.

I borrowed a good example of that multipattern LDC from a recordist who was extraordinarily helpful, Peter Nothnagle. This was thirty years ago. Back then the Beyerdynamic was considerably cheaper than the Neumann counterparts. I realize that Neumann now has similar microphones for similar prices.

What would you say are stand-out condenser microphones, large or small diaphragm, in the $100-$300 range? I keep clicking on the Sweetwater ads, finding a lot of interesting microphones in that price category. I would prefer microphones that don't require an outboard power supply box for practical reasons.

 

[Ricardus]

I've used Rode NTK's a bit. They have only a tiny bit of the tube goodness. They are so quiet and flat in response I didn't find it worthwhile vs other good FET's. The disadvantage was having to worry with the extra box which supplied power to the tubes.

I got an NTK for free, and the tube was going microphonic, so I replaced it, but when I had it open, I noticed the PCBs for the NTK were the same as for the variable pattern K2 (they literally say K2 right on them). They just used a 1-sided capsule in the NTK for cardioid. So I bought a Peluso two-sided C12 capsule and wired both sides.

Same with the PSU. It was ready to accept a pattern changing pot right out of the box. So for very little investment I got a K2.

 

[Ricardus]

I have a friend with a studio (mostly all analog) and he collects vintage gear and has one of just about every classic tube mic there is. When they're working, they definitely sound good. Classically you see so many photos of great singers singing into cool tube mics (U47s, ELAM 251s) that it's almost a rule that you have to use them for the lead vocal track.

That said, there are so many good solid state mics, if you've got a good quality one, no one is going to know you didn't use the tube mic.

I own a pair of Shure KSM44s, and I would put them up against any mic there is, and it would compare nicely in subjective listening tests. In fact if you're thinking of buying a U87, save your money and buy 2 KSM44s.

 

[DonH56]

Makes me wish the Alesis mixer I'm using had true parametric controls. On the other hand, that presence boost is pretty useful for coming across in a zoom assembly. We also have Sennheiser [835?], had cheap Behringer cardioid dynamic mikes. There's a small dynamic Sennheiser intended for guitar amps [just drape the front of the mic over the cab's speaker] for mic-ing hand percussion.

Yah, if you need to bring out the vocals, that is exactly why they have the boost, and it is perfect for that job. On instruments it tends to make them too "bright" IMO.

Giles brought the microphone, that's why. Would have preferred the cardioid option but didn't have it. The singer was close enough to the microphone to properly balance and "sit" in the mix. When I was getting paid for pro audio my default microphones were Neumann 140's and those freaky Octave small diaphragm condenser mics. Audience wasn't an issue with the omni, it was only used for recording.

Understood, I was curious if there was a reason he brought the omni vs. a different mic.

We've got an AKG C1000, what do you think of it? I haven't used it. I recall working with an old pair of AKG 414 microphones, didn't care for them. That might be on account of their age. Microphones do not age well. I also recall working with the AKG 451, found it to have a "steely" coloration, very useful for certain types of guitars but a little harsh for me otherwise.

It's a decent medium-diaphragm end-fire mic. It doesn't have the sensitivity of the large condensers but is a lot better than typical dynamics, and has a better noise floor than the small-diaphragm types (plus adds some directionality which I tend to appreciate). Like any end-fire you have to watch out for the proximity effect and such. I tended to use it as a "solo" mic with a pair of larger condensers for the overall group. At times I hung an omni a ways back from the group, someplace around the first to third audience row depending on the venue, to pick up some of the "ambience" of the venue. I found a subtle mixing of a bit of that omni would give the recording more sense of "space". There are other, easier, arguably better ways to do that, natch, but I got a fair number of positive comments by including a little more of the clapping and occasional outburst from the audience as well as a mix that sounded more "full". YMMV.

Re. the AKG C414: There are a lot of varieties ("flavors") with the response tailored for different applications so you might like one and hate another. But recording engineers tend to pick mics for the sound the group and they want and it is very much an individual thing. You probably have a lot more experience with different mics than I, and certainly more recent, as after my early "pro" days I was limited to what I could afford as a what would now be called a "semi-pro" recording engineer. The engineers I worked with in the studios usually had a large array of different mics to choose from.

 

[dfuller]

"sound quality" between microphones is frequency response.

Yes, but it's more complicated than that because the polar pattern behavior changes the response - mics with the same capsule(s) in omni don't have the same response as in cardioid or figure 8 etc etc.

90% of the sound of any mic is the capsule and all its characteristics. A FET 47 sounds very much like a tube 47.

re: tube mics, I have to be honest - most of them I do not care for. I do however tend to prefer a coupling transformer rather than a transformerless design for condensers, it gives some character.

 

[Robin L]

Yes, but it's more complicated than that because the polar pattern behavior changes the response - mics with the same capsule(s) in omni don't have the same response as in cardioid or figure 8 etc etc.

90% of the sound of any mic is the capsule and all its characteristics. A FET 47 sounds very much like a tube 47.

re: tube mics, I have to be honest - most of them I do not care for. I do however tend to prefer a coupling transformer rather than a transformerless design for condensers, it gives some character.

Thanks, that's good to know.

I have noticed a sound character in transformer coupled tube gear that seems to have an effect that I can't get with EQ, like a variable degree of focus that is at its best mid-band.

I've been looking at the Warm Audio Offerings---replicas [or at least attempted replicas] of vintage microphone designs. I wonder if any of you might have some experience with their KM84 replica and the WA 251:

Warm Audio WA-84

Many engineers believe that Neumann's classic KM84 has never been bettered. Have Warm Audio produced an affordable alternative?

www.soundonsound.com

Warm Audio WA-251 Large-diaphragm Tube Condenser Microphone Reviews | Sweetwater

Read Sweetwater customer reviews for Warm Audio WA-251 Large-diaphragm Tube Condenser Microphone. Rated 5.0 / 5 by 47 customers!

www.sweetwater.com

 

[Blumlein 88]

I have a couple WA84s. They do have some of that sound signature of transformers in a good way. I've not used them a lot yet. Best I can tell without having a KM84 on hand, they sound much like them only they have a stronger bottom end. The quoted FR indicates more low end as well.

I've not gotten to do any recording in recent months. I'm wanting to really use these. Currently I think they are my favorite microphones.

There is a review in Sound on Sound of them. I know they are pushing products, but their description matches what I hear from them.

 

[MakeMineVinyl]

I have a couple WA84s. They do have some of that sound signature of transformers in a good way. I've not used them a lot yet. Best I can tell without having a KM84 on hand, they sound much like them only they have a stronger bottom end. The quoted FR indicates more low end as well.

I've not gotten to do any recording in recent months. I'm wanting to really use these. Currently I think they are my favorite microphones.

The KM84 was the darling mic which was used very heavily when I was at Sound City. Myself, I always liked the MD421, especially on drums.

 

[Robin L]

I have a couple WA84s. They do have some of that sound signature of transformers in a good way. I've not used them a lot yet. Best I can tell without having a KM84 on hand, they sound much like them only they have a stronger bottom end. The quoted FR indicates more low end as well.

I've not gotten to do any recording in recent months. I'm wanting to really use these. Currently I think they are my favorite microphones.

Thanks, that is very useful information. I figured I blew it when I decided that the KM 140 would be better. I had a pair of the omni KM 130s as well, the 130s being "better" than the 140s overall, and the 140s not as sweet as the KM 84s I've used. However, using the 140s might have saved my skin a few time, on account of better isolation from funky AC.

 

[Robin L]

The KM84 was the darling mic which was used very heavily when I was at Sound City. Myself, I always liked the MD421, especially on drums.

What the h--l were you doing there?


Sennheiser MD 421? Why did you like it?