Do Mics Warm Up ?

[ido1957]

I've got a Rode NTK mic that I really like. It seems like the mic gets louder and thicker? brighter? sounding after about a half an hour of turning it on. (It has a power supply and a tube). It really does seem to take a while to warm up and I'm wondering if this is just my imagination or would this occur with a tube mic like this one? Anyone else seem to experience this phenomenon?
PS - My voice warms up a bit more after that much time so that could be a partial contributor.

 

[DonF]

Half an hour sounds about right to me. I don't think it's just your imagination.

Don

 

[MCI2424]

I've got a Rode NTK mic that I really like. It seems like the mic gets louder and thicker? brighter? sounding after about a half an hour of turning it on. (It has a power supply and a tube). It really does seem to take a while to warm up and I'm wondering if this is just my imagination or would this occur with a tube mic like this one? Anyone else seem to experience this phenomenon?
PS - My voice warms up a bit more after that much time so that could be a partial contributor.

YES. Tube mics take time to warm up.

 

[Robert D]

Yes, yes, yes. The cathode in a vacuum tube needs to be hot to emit electrons. Tubes actually have a heater filament to heat the cathode up. It takes a little while (about a half hour as stated above) for the cathode to come up to temperature. I have an NTK also, nice mic.

 

[RezN8]

Lava Lamp

Room temperature plays a part here too. One of the reasons many studios have a Lava Lamp.

Turn on the tube mic, tube amp, etc. at the same time you turn on the Lava Lamp. When the lava begins to flow your tubes should be about ready.

Cheers, Rez

 

[Robert D]

Yeah, but it's so hard to find a tech that can properly calibrate a lava lamp these days.

 

[omtayslick]

Yeah, but it's so hard to find a tech that can properly calibrate a lava lamp these days.

Maybe Harvey. He's old school.

 

[boingoman]

Tubes warm up pretty quick, it's the rest of the stuff that takes awhile to stabilize.

 

[Harvey Gerst]

Maybe Harvey. He's old school.

Hey, I had to walk to school and back everyday...

...in the snow...

...uphill...

...both ways!!!

 

[Robert D]

Tubes warm up pretty quick, it's the rest of the stuff that takes awhile to stabilize.

Then the half hour rule should apply equally to FET mics, and solid state preamps, which actually isn't a bad idea. Pretty much all electronic components have temperature co-efficiants, and all circuits have a transfer function that changes slightly, or not so slightly with temperature, depending on how thermal stability was taken into the design consideration and component selection.

It's true that the cathode will warm up enough to start emitting electrons pretty quickly, but thermionic effects can occur for quite a while. Until enough electrons have migrated off the cathode and into the cloud to reach equilibrium (I'm reaching way back here), then the tube isn't stable. Trying to use a tube too quickly can even damage the tube, an effect called cathode stripping.

 

[thajeremy]

Hey, I had to walk to school and back everyday...

...in the snow...

...uphill...

...both ways!!!

with no shoes???

Grandpa??? is that you???

 

[boingoman]

Then the half hour rule should apply equally to FET mics, and solid state preamps, which actually isn't a bad idea. Trying to use a tube too quickly can even damage the tube, an effect called cathode stripping.

I'm sure it has some effect. When I'm troubleshooting I definitely try to check out things as they warm up, some problems only show up when things are cold, some when they are hot, due to expansion and contraction of components and joints. Tubes and their support stuff throw of tons of heat, enough to have an effect on other components and the sound changes until the temperatures stabilize. As far as cathode stripping, it certainly happens, but even after a minute or so the cathode will be hot enough to be safely used.

 

[Robert D]

Tubes and their support stuff throw of tons of heat, enough to have an effect on other components and the sound changes until the temperatures stabilize. As far as cathode stripping, it certainly happens, but even after a minute or so the cathode will be hot enough to be safely used.

Good points. I just give everything about half an hout to warm up, tube or not.

 

[thajeremy]

Good points. I just give everything about half an hout to warm up, tube or not.

same here...I turn on my pre's a good half hour or so before my clients get here...not so much for dynamic mics...but for condensers....

 

[mrhotapples]

Don't all electrical components have a burn in time? Like, a certain amount of use before they operate at ideal parameters?

I personally leave my phantom powered mics on unless they're going away/not being used for anything soon, and I generally turn my interface on 10-20 minutes before use. I notice that my M177s always sound better this way, always. Especially on voices. Things are less strident. My Firepod's pres also seem to get a bit fatter in the lower mids.

My guitar amp stays on and out of standby after initial powering up for as long as possible before being used. It gets warm and there's a difference in sound after 20-40 minutes. I think in general, 30 minutes is a good way to go about it.

 

[Zaphod B]

Hey, I had to walk to school and back everyday...

...in the snow...

...uphill...

...both ways!!!

You must know my dad!

 

[chestwick91]

Tubes warm up pretty quick, it's the rest of the stuff that takes awhile to stabilize.

This guy actually said it best...tubes do warm up quick, the warmer the are the better, however it's the rest of the internal electronics you want to give a half hour
....same with amps when you record them or gig um

Also i always wanted the ntk, and you guys made me just buy it...lol

 

[ido1957]

This guy actually said it best...tubes do warm up quick, the warmer the are the better, however it's the rest of the internal electronics you want to give a half hour
....same with amps when you record them or gig um

Also i always wanted the ntk, and you guys made me just buy it...lol

Congratulations - I hope you like it as much as I do....