A Mic below 50Hz? Why?

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Re: A Mic below 50Hz? Why?

Post by The Elf »

All I would say is to be sparing of what is allowed to go that low. I make it a point that only one signal gets to live in that lowest region, and I will even shave some of that to preserve headroom.
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Re: A Mic below 50Hz? Why?

Post by awjoe »

Hugh Robjohns wrote: Tue Aug 24, 2021 5:59 pm
ManFromGlass wrote: Tue Aug 24, 2021 5:36 pmWhy would I want an awesome mic for a room like that?

Why wouldn't you? If the mic isn't capable of capturing the most accurate (or most desirable) sound why bother at all?

But it's worth remembering that phase-shift mics -- meaning most conventional cardioids, hyper-cardioids and super-cardioid (including multipattern capacitor mics) -- rarely if ever have a bass response that extends much below 40Hz. The physics simply doesn't make it practical.

If you want to pick up stuff below that then you need to use an omni (which will typically stretch down to 20Hz or lower) or arguably a good quality ribbon fig-8.

I pull out my trusty R-121 and think: 'On the bass cab? Interesting.'
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Re: A Mic below 50Hz? Why?

Post by ManFromGlass »

I don’t know how many times I’ve read through everyone’s comments (thanks!) and what I am taking away is that even for a mono recording an Omni or ribbon should have better sounding low end as there would be no low end phasiness that comes from the roll off that cardioids have. Would it be correct to say the low end would be clearer?
Plus there would be no low end proximity effect from the Omni, just the natural low end of the instrument.
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Re: A Mic below 50Hz? Why?

Post by Tim Gillett »

It will capture the low bass only if the low bass is there to be captured. Many bass amps and pianos for instance do not go down as low as even a true 40 Hz so it can all be a bit pointless in the real world.
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Re: A Mic below 50Hz? Why?

Post by Hugh Robjohns »

As always, it all depends on the specific situation and the requirement, so it's worth being aware of the pros and cons and the factors that influence a decision... as has been discussed at length.

In some recording situations being able to capture audio from the lowest octave(s) is crucially important.

In others there may be nothing worth recording in that region of the audio spectrum at all. And furthermore, having a mic with an extended LF response can actually create problems by capturing unwanted non-audio content.

In any case, most directional mics are already rolling-off by 50Hz, and if you want/need to capture signals in the 10-50Hz area you're almost always going to have to use good quality omni-directional mics, with all their associated practical implications.
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Re: A Mic below 50Hz? Why?

Post by awjoe »

Yeah, all the usual caveats are understood - I simply like trying out something I haven't tried before in order to see how it works.
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Re: A Mic below 50Hz? Why?

Post by Trent in WA »

John Willett wrote: Wed Sep 22, 2021 6:39 pm
blinddrew wrote: Tue Aug 24, 2021 10:19 pm
ManFromGlass wrote: Tue Aug 24, 2021 8:38 pm As for what awesome mic means to me, I didn’t express myself correctly.
I mostly close-mic, recording 1 instrument at a time. The room does not add any desirable sound that I want to include in the mix. So I’ve ruled out an omni mic.

An omni isn't just about capturing the room though (or not as desired), as Hugh mentions above, it's about capturing the true character of the instrument. With guitar, for example, one of my preferred close mic'ing techniques is with a pair of SDC omnis, one around the 12/14 fret, one behind the bridge, both about 8" away. The proximity to the guitar means that I get a lot more instrument than room, the omni pattern means no proximity effect, and the natural response, I find, gives a more honest picture of the instrument, despite the close-mic'ing.
It's certainly worth trying if you have a less-than-good room and a pair of omnis around.

And the inverse-square law means that the closer you get the less room you get.

Omnis are great mics - I love them.

I know Hugh has already said most of what I would say (thanks Hugh) - but the loudspeakers in my living room go down to 30Hz and lower than that in the roll-off. :thumbup:

This discussion is one of the reasons why this is the best recording and mixing resource on the web. Last night on a, I tried close-micing my acoustic guitar at the 14th fret with my Lewitt 441 set on omni, and it was a revelation. Thank you all!
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Re: A Mic below 50Hz? Why?

Post by ef37a »

I don't have any omni mics (love a pair for son) but regarding Very Low Frequencies I have, for the last six month or so been listening to everything from my TV and computer through a pair of Mission 775s. These are imposing speakers driven from a 50Wpch Arcam amplifier. I have been very surprised at the amount of very low frequencies from various sources. I expect VLF on sci-fi proggs but quiz shows?

The one place I don't hear VLFs is radio 3 except on the rare occasion there is an organ recital and even some of those don't go THAT low.

I now use my Tannoy Reveal 5As and don't really miss the bottom octave, they are still pretty punchy. I am going to get a sub crossover unit and just run the Missions as subs for the craic on Star Treks!

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Re: A Mic below 50Hz? Why?

Post by Airfix »

Trent in WA wrote: Thu Sep 23, 2021 6:26 pm This discussion is one of the reasons why this is the best recording and mixing resource on the web. Last night on a, I tried close-micing my acoustic guitar at the 14th fret with my Lewitt 441 set on omni, and it was a revelation. Thank you all!

He's lovely - is he not? OK .. could be a girl. Who knows - like a mic below 50Hz - the air - the energy
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Re: A Mic below 50Hz? Why?

Post by awjoe »

Okay, I'm intrigued with the omni idea. I'll start with my AT 4050 in omni mode, but I'm wondering what dedicated omnis you might suggest. I'm going to try it on everything. In my case, everything is:

Ukulele
Acoustic guitar
Guitar amp
Bass Amp
Electric piano
Hand percussion
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Re: A Mic below 50Hz? Why?

Post by Airfix »

Close mic - right?
Omnis are bitches - OK you know that - everyone knows that - Do you want to record the room?
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Re: A Mic below 50Hz? Why?

Post by 3rdConstruction »

I had the impression that a multi pattern mic set to omni did not have the same characteristics as a true single diaphragm omni. Am I mistaken?
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