If only two mics... ?

[ricardo]

BTW, there are some caveats about using the Calrec Soundfield Mk4 in Stereo due to my not actually using it for stereo until I left Calrec.

The most damning is that the Stereo output is out of phase. Mea culpa, mea culpa, mea maxima culpa

 

[thor.zmt]

As I said earlier, I'm the last remaining High Priest of Tetrahedral Ambisonic mikes

Not really. A (chinese) customer wanted a livestreaming Mic that was different. I tried to get him sold on a first order Amisonic Mic, on the principle that Ambisonic is de-factor VR audio and this could be used for example in nature for an immersive Audio experience.

Extensive DSP build in to reliably make livescreamers sound ok, so compressor, autotune, reverb, sampled sound FX. Nice Brass 25mm Electret capsules. Wired USB or Wireless (aptX . I had intended a secondary software option for "recording" use. And a second version with polarisation and real condensor capsules.

Customer declined and instead got his brand screened on a BM800 and "livestreaming sound card". Last I looked the bundle was still for sale on Taobao for less than factory cost.

I got to try a Calrec Soundfield in the front of my "Triangular Microphone setup with dimensions similar to a Decca Tree and similar general intention, that is however nothing like a Decca Tree to appease certain people". I liked it, but I would probably have needed a lot more time to get the measure of it and get the best out of it. Alas, even 5th or 6th hand the price was insane for me.

If anyone wants to DIY one (worth a try), the new Chinese Brass 25mm Capsules are probably a good call for a first try. More details here:

Soundfield microphone by K Farrar · WW October 1979

My Fantasy Audio Christmas Present - SoundField Ambisonics Microphone

Make a 3D printed tetrahedron to hold the capsules.



Electronics are unchallenging.

It's probably one of the most interesting microphones to DIY and the answer to "what is the best single microphone to record classical music with".

Thor

 

[thor.zmt]

There are only 2 arrangements that accurately capture the sound of a good hall.

• Blumlein coincident Fig 8s @ 90 which also gives very good localisation of sources on speaker playback
• Omnis. Spaced omnis give good sound and usually have better LF than modern Fig 8s or cardioids except TetraMic. But localisation is non-existent.

Place a baffle behind the Blumlein array (to limit rear pickup) and place your spaced Omni's in a configuration that would be called by many a Decca Tree.

Except it is not actually by Decca, does not use the distinct flown "tree" structure, uses different microphones to the original Decca Tree and mustn't be called anything remotely like "Decca tree", lest the universe collapses and is replaced by something even more incomprehensible and challenging than what we have now. Some say that somebody already said that though.

Other coincident or semi-coincident configurations can be used in front.

The sound processing should be obvious. Front pair main stereo Array, Lowpass on the Omni's as "bass fill in" for the front array's rather castrated bass, extra level controls on a gently sloped down (x-curve) filtered Omni full bandwidth. Back in the 80's I had a pre/mixer combo box I made (as part of my Tonmeister "Meisterstueck") for this with Mic's being generally Microtech Gefell.

Seems this is kinda used quite frequently these days. I "invented" (I am sure a dozen guys will jump up and claim they did it before me - probably - not claiming priority, just independent work) this setup in the 80's in what was then communist East Germany. I can recommend it.

Thor

 

[k brown]

I was referring to using a Calrec Soundfield or TetraMic for STEREO. Agree with you mostly on surround though I live & hope

There's an interesting phenomena for those using a properly calibrated soundfield for the first time in a good hall. They always start off with their favourite mike arrangements quite near the performers

Then little by little, they move the mike back and twiddle the patterns and invariably end up with Fig 8s @ 90 placed where it sounds best to the Mk1 Human Head.

At this point, they generally say, this cannot be and start over again

This was John Atkinson's experience when he used it for the first time. He didn't believe me when I told him that was what would happen.

Doesn't surprise a bit; Blumlein is the only coincident technique I ever found listenable.

 

[Emmathom]

Not really. A (chinese) customer wanted a livestreaming Mic that was different. I tried to get him sold on a first order Amisonic Mic, on the principle that Ambisonic is de-factor VR audio and this could be used for example in nature for an immersive Audio experience.

Extensive DSP build in to reliably make livescreamers sound ok, so compressor, autotune, reverb, sampled sound FX. Nice Brass 25mm Electret capsules. Wired USB or Wireless (aptX . I had intended a secondary software option for "recording" use. And a second version with polarisation and real condensor capsules.

If anyone wants to DIY one (worth a try), the new Chinese Brass 25mm Capsules are probably a good call for a first try. More details here:

Soundfield microphone by K Farrar · WW October 1979

My Fantasy Audio Christmas Present - SoundField Ambisonics Microphone

Make a 3D printed tetrahedron to hold the capsules.

View attachment 141809

Electronics are unchallenging.

It's probably one of the most interesting microphones to DIY and the answer to "what is the best single microphone to record classical music with".

Thor

Interesting...
No phantom needed (electret) / RJ45 CAT8 cable for 4 outputs ?
So you got 4 separate outputs = is it possible to mix them in a stereo way and how ?
And what does each of them (4 mics) record ? left, right, front & rear ?
Please tell us more about this setup... (I guess it needs a special interface between the mic and an external pre...)

 

[MicMaven]

For sure, but probably the CEO and definitely the head of the guitar amp division should have a ready answer.
Maybe James's friend was just making small talk and didn't care enough to actually bring it up to the CEO

Sure they did! And it was NOT just small talk. The guy is so dag blamed cock sure he knows everything because, after all HE is on the BOARD, don't-cha ya know - shoot, you cannot tell him anything. He told me the guys in the factory tried to explain it, but he wrote them off as dumb factory workers. I cannot account for that degree of arrogance.

So, you guys might understand WHY I WORKED ALONE most of my career, instead of grubbing for a big corporate entity. I tend to speak my mind ... James

 

[Emmathom]

Hi

By starting this topic "If only two mics...?" I did not mean to have only one pair of mics, but to use (if possible) only one pair at a time...
Concerning my own setup and knowing that I record almost only acoustic ensembles in rather large places, I will limit my equipment to one SDC omni pair (LA Omni1) + one SDC cardio pair (DIY Schoeps-like) + one fixed ORTF (Superlux S502 v1 with @MicUlli PCB) + one LDC cardio-omni-fig8 pair with Ari K47flat (t.bone SC1100 modified).

I have a sE2300 (3 pattern) to resell but can't get a buyer for weeks so I'm thinking about keeping it but with capsule replacement (because the sE capsules are their weak point while their electronics are fine - they announce 9dB self-noise - which I doubt). I have also a DIY 6AK5 LDC cardio pair that I like on strings (cello, double bass) and harpiscord.

About different 2 mics setup's and regarding your comments I noticed that :

- Blumein can be set if the room is not too vast (because of fig8 rear lobes capturing reverb) > 2 SC1100 in fig8
- ORTF is great for sound spacing & precision (but not well suited for mono listening > but I don't care about those who listen in mono) > S502
- AB is great for the sound, the feeling of the acoustic, the "truh" of the sound (but not precise to locate instruments in space) > LA Omni1 pair
- XY for small ensemble & close palyers (like a duo violin + cello for example) > "Schoeps-like" cardio pair
- a 3 mics arrangement, strictly Decca or inspired by > 2 SC1100 @ rear + sE2300 tweaked @ front (or LA Omni1 pair @ rear + one LDC in front)

In another hand, these gear (3 SDC pairs + 1 LDC multi pair + 1 tube LDC cardio pair + 1 LDC multi) allows me to make lots of close micking configurations when needed

 

[Emmathom]

The sound processing should be obvious. Front pair main stereo Array, Lowpass on the Omni's as "bass fill in" for the front array's rather castrated bass, extra level controls on a gently sloped down (x-curve) filtered Omni full bandwidth. Back in the 80's I had a pre/mixer combo box I made (as part of my Tonmeister "Meisterstueck") for this with Mic's being generally Microtech Gefell.

I did some days ago a recording of a sextet with a friend who brought a Schoeps cardio pair. We set his mics in ORTF at front and my LA Omni1 at sides and we recorded 4 tracks only.
Back to monitoring, well the fact is that the Schoeps don't lack bass at all and there was no point in adding some of the omni's, filtered or not.
The 2 stereo tracks are very different soudning (of course), both very interesting but not able to be melted in any way. The Schoeps have been kept on the LA (also because they have been set too spaced from each other I must confess).

And yes, we noticed that even if the omni's sound great (really), the placement of the musicians is not precise compare to the Schoeps in ORTF where you can say where is the cello, where is the solo violin, etc