If only two mics... ?

[thor.zmt]

@thor.zmt proposes using two LDC with 2 independant capsules single diaphram (back to back) + 2 independant circuits + 2 signal outputs

Nope, I don't propose that at all.

I propose a single dual diaphragm capsule, witch each diaphragm driving a full "microphone" electronic and bias on the backplate. So we don't switch around patterns in the classic sense, we just get two sets of audio signals.

By adjusting relative phase, frequency response and levels of the two recorded outputs in the DAW and then summing, we can create any desired microphone directivity post facktum.

There should probably be a "generic Cardioid/8/O LDC" preset (set) for quick check during setup, but you postpone the final choice on directivity until later.

Past that, while backplate design in the capsule and Microphone head design impact the sound, most of these are non-linear frequency response aberations and or varying directivity with frequency.

One of my more interesting setups was a B&O Stereo Ribbon Mic in front of a modified Decca tree made on stands and large RCA variable pattern Tube condensors in the back.

Very little beats ribbons when it comes to transients and "air". But they are Figure 8 only, the ones I know. So often an absorbent baffle is needed behind them or it gets too wet.

Thor

 

[Emmathom]

Ok, I misunderstood, sorry...

 

[cfanzalone]

My experience with smaller (even bigger) ensembles and choirs for 2 mics: Matched pair of Earthworks QTC1 (also called QTC40's). Realistic, just like being there. You have to play with the spacing and distance, of course, to suit you and your room's needs. Better yet!: 3 mics ala "Decca Tree" (one to capture the 'middle' and allow many more options on the spaced pair) . Many famous recordings have been done with this array and I have had fantastic results. I have never been a fan of cardioid mics for these type performances...the low frequency dropoff vs. distance can be severe.
"Purists" have said that the Earthworks are "noisy", but I've found the realistic results FAR outweigh the little extra self-noise.
Look up DPA "Mic University...or something like that...to learn different 2-mic arrangements, as there are many.

 

[k brown]

Nope, I don't propose that at all.

I propose a single dual diaphragm capsule, witch each diaphragm driving a full "microphone" electronic and bias on the backplate. So we don't switch around patterns in the classic sense, we just get two sets of audio signals.

By adjusting relative phase, frequency response and levels of the two recorded outputs in the DAW and then summing, we can create any desired microphone directivity post facktum.

There should probably be a "generic Cardioid/8/O LDC" preset (set) for quick check during setup, but you postpone the final choice on directivity until later.

Past that, while backplate design in the capsule and Microphone head design impact the sound, most of these are non-linear frequency response aberations and or varying directivity with frequency.

One of my more interesting setups was a B&O Stereo Ribbon Mic in front of a modified Decca tree made on stands and large RCA variable pattern Tube condensors in the back.

Very little beats ribbons when it comes to transients and "air". But they are Figure 8 only, the ones I know. So often an absorbent baffle is needed behind them or it gets too wet.

Thor

I wouldn't describe that as a "modified Decca Tree"; there's nothing remotely 'Decca' about it - it's just a three mic array of you're own concoction. Just as a pair of hypercardioids a foot apart at 110 degrees wouldn't be ORTF either, just because it's a pair of mics at 110 degrees.

 

[thor.zmt]

I wouldn't describe that as a "modified Decca Tree"; there's nothing remotely 'Decca' about it

There is. The spacing is similar, the rear Mic's are normally Omnis and the crossed 8 front array can be mixed to mono, at which point you are at "Decca".

Based on the results, I might even suggest that it is a valid alternative, which delivers some sonic features an actual Decca Tree with M52's doesn't.

Thor

 

[k brown]

There is. The spacing is similar, the rear Mic's are normally Omnis and the crossed 8 front array can be mixed to mono, at which point you are at "Decca".

Based on the results, I might even suggest that it is a valid alternative, which delivers some sonic features an actual Decca Tree with M52's doesn't.

Thor

Sorry, but no, not close enough to qualify.

The Decca Tree as used by them beyond a few early experiments was fairly specific dimensions and designed specifically for use with the Neumann M 50. The only exception was a handful of early sessions done by only one of their engineers (Gordon Parry) at only one of their recording locations (Sofiensaal, Vienna) that used Neumann KM56s; after the last of those, all others were with M 50s.

The only exception to the dimensions used (L/R at about 4' 6", and C about 2'3" forward) was the very occasional use of a smaller Tree, about 40" x 20" on chamber ensembles.

The only significant variations from session to session were in the mix level of the center mic, which was done by ear for each situation.

The Decca Tree can only produce it's expected sound by adhering to these dimensions and using three M 50s, or close equivilents in the form of diffuse field response omnis mounted in 40-50mm spheres (what DPA call Acoustic Pressure Equalizers). The particular frequency-dependent directionality of such microphones is required for the sound of the Tree to 'gel' properly and effectively.

Many other triangular arrangements of three microphone can sound perfectly fine, but anything other than what's described above is not a Decca Tree. Just as any old near-coincident pair of any old pattern of mics is not ORTF (or NOS, or DIN, etc.). If these terms don't have clear and commonly understood meanings, then they become useless.

 

[Barry Hufker]

Having used Shure KSM141s, I wouldn't use them for a main pair. I love the switchable capsules but check their frequency response to see if it's what you'd really want. I've liked them as spot mics…

 

[thor.zmt]

Sorry, but no, not close enough to qualify.

I wrote "MODIFIED DECCA TREE", making clear that while derives from the original work by Decca it is dissimilar and not identical. It acknowledges the origin of the concept, rather than claiming to be a the exact equal.

It was actually meant to solve some of drawbacks I perceive in many Decca recordings done this way and did exactly that. Note, the outcome was DIFFERENT I make no claims to better or worse, that is personal value judgement except stating a personal preference for my own person.

There is nothing so sacred it may not be challenged or improved. The holiest cows make the best smash-burgers.

The Decca Tree can only produce it's expected sound by adhering to these dimensions and using three M 50s

And if the arrangement is MODIFIED the result may be different to the Decca original in ways that may or may not preferable in the specific situation.

Many other triangular arrangements of three microphone can sound perfectly fine, but anything other than what's described above is not a Decca Tree.

But IT MAY BE a MODIFIED Decca Tree.

Just as any old near-coincident pair of any old pattern of mics is not ORTF (or NOS, or DIN, etc.).

Yet they may be modified FROM ORTF (or NOS, or DIN, etc.), for specific reasons.

Technically speaking, if we want to attract more "For Fox's sake buy me a Firking Beer" (Got the T-Shirt at the Fox and Firkin Pub in Lewisham when it still served Guinness with a Shamrock on top, for those who know the meaning), placing three M-50 on individual stands with the correct elevation and spacing is also NOT A DECCCA TREE, even if the recorded results are 100% identical.

This way madness doth lieth.

I'm not going on that particular snark hunt, not for king and country, even if king and country expect.

Ok, for king and country! Without Decca Trees and instead X-Mas shaped trees.

Happy holidays, goodwill to all mankind and all that jazz....



Thor

 

[cfanzalone]

Ahhh, yes....we all have our own opinions and experience...The Decca Tree is/was a concept in progress over time, actually starting out with M49's, with different baffle configurations, as the 3 mics and gradually moved to M50's as the spaced pair with a third (center) an M50. I have a litany of original information from Wilkerson s well as London Decca Engineering notes from 1960's opera recording sessions....
London Decca used occasional spot mics for certain instruments depending on the orchestra size and, typically, M49's as singer spot mics on stage.
Remember that London Decca Engineers were REAL engineers, not 'button pushers' like most of us...many board electrical and even mic electronic changes were made without telling!!!

The mics don't make the Decca Tree, it is a configuration that is time tested.

Yes, K Brown, I am familiar with the M50: (rented many of them) K50 nickel SD capsule mounted in a plexiglass sphere, which 'shapes' the sound more directional as the frequency rises. I have 50mm wave guides attached appropriately to my QTC1's which emulate this curve almost exactly....but certainly not a $25,000.00 M50 in excellent condition)...we do our best, eh??

...But I leave this conversation only to add that, yes, appropriate long ribbon mics in a Blumlein array with a center mic is also very nice.

So be it for the rest of you to debate this to death.

Blessings

 

[cfanzalone]

Addendum, this is about 2 or 3 mics within financial parameters that serves one best for your given project. It's not about "who knows what"...

Take a chill pill, do your research, take every comment with a grain of salt and experiment until you're pleased....it does take experimentation.

Th, Th, Th, Th,..That's all folks! LOL

 

[k brown]

When did RCA ever make a vari-pattern condenser mic?

And what's an M52?

 

[terry setter]

Only one thing to add: have three mics. I often used a center fill/spot when doing concertos and it really helped. Also, one of your two might break, or get stolen, or any other heartbreaking thing that happens to microphones.

Have three!

 

[thor.zmt]

When did RCA ever make a vari-pattern condenser mic?

These were antiques, RCA was written on the Shell. Very likely not made by RCA.

I do not know where my friend acquired them. He collected Mic's and other gear. A lot was ex. BBC, we lived in London. As for my friends items, he collected them, I borrowed them and used them to record. The Mic's were big, tubed ran hot, big external PSU BOX, RCA Logo on all of the Bits. So we called them the "RCA" Mic's. They may have been any number of OEM actually. I'm not really THAT MUCH into mic porn.

A shedload of gear that "never existed" turned up there from the BBC and others. One time I bitterly complained to Sony's Head office in Japan about the fact that I could not get info from Sony UK about a professional portable Betamax recorder and Camera I was trying to fix and who constantly told me it didn't exist.

Sony JP send me a nice letter stating that it existed but was only for specific customers. They did however send along the service manual for the base model (Japan only), notes, in part hand written notes on the changes and I got the thing fixed and monetised. SONY were absolutely solid back than.

Mustava been 1994 or so, before I changed my side hustle while doing my second degree at the University of North London to something that paid a lot better. Starving students will do almost anything for a few Quid.

And what's an M52?

M50, my bad.

I wish my memory was as good and precise as yours. I'm sure you never make minor mistakes.

Me, I have dyslexia, brain fades and frequently misremember stuff, flip letters, mix up numbers. Appy Polly Logie.

There so many things called M something, I frequently get my lions crossed. I think the M50 somehow crossed Lions in my Head with M551 Sheridan and then added one and dropped five.

Maybe. It kinda get's noisy in there sometimes.

Greetings from the Thai Riviera, where we celebrate Constitution Day, with Sunshine and a balmy 31 Degrees under Palm's. This reminder of olde Blighty serves to make me appreciate just how great it is not be back in Blighty.



Thor

PS, I often use names the way most common people do (obligatory reference to a Pulp Pop Song), casual and in a descriptive way. So for example I call what 3M insists are generic hook and loop fasteners "Velcro", generic Paper tissues Kleenex or Tempo, brown sauce "HP's", a Mic with RCA written on It "RCA Mic" and so on. Pardon my liberties with the noble english language.

 

[k brown]

These were antiques, RCA was written on the Shell. Very likely not made by RCA.

I do not know where my friend acquired them. He collected Mic's and other gear. A lot was ex. BBC, we lived in London. As for my friends items, he collected them, I borrowed them and used them to record. The Mic's were big, tubed ran hot, big external PSU BOX, RCA Logo on all of the Bits. So we called them the "RCA" Mic's. They may have been any number of OEM actually. I'm not really THAT MUCH into mic porn.

A shedload of gear that "never existed" turned up there from the BBC and others. One time I bitterly complained to Sony's Head office in Japan about the fact that I could not get info from Sony UK about a professional portable Betamax recorder and Camera I was trying to fix and who constantly told me it didn't exist.

Sony JP send me a nice letter stating that it existed but was only for specific customers. They did however send along the service manual for the base model (Japan only), notes, in part hand written notes on the changes and I got the thing fixed and monetised. SONY were absolutely solid back than.

Mustava been 1994 or so, before I changed my side hustle while doing my second degree at the University of North London to something that paid a lot better. Starving students will do almost anything for a few Quid.



M50, my bad.

I wish my memory was as good and precise as yours. I'm sure you never make minor mistakes.

Me, I have dyslexia, brain fades and frequently misremember stuff, flip letters, mix up numbers. Appy Polly Logie.

There so many things called M something, I frequently get my lions crossed. I think the M50 somehow crossed Lions in my Head with M551 Sheridan and then added one and dropped five.

Maybe. It kinda get's noisy in there sometimes.

Greetings from the Thai Riviera, where we celebrate Constitution Day, with Sunshine and a balmy 31 Degrees under Palm's. This reminder of olde Blighty serves to make me appreciate just how great it is not be back in Blighty.



Thor

PS, I often use names the way most common people do (obligatory reference to a Pulp Pop Song), casual and in a descriptive way. So for example I call what 3M insists are generic hook and loop fasteners "Velcro", generic Paper tissues Kleenex or Tempo, brown sauce "HP's", a Mic with RCA written on It "RCA Mic" and so on. Pardon my liberties with the noble english language.

Yes, #31 was churlish and unnecessary.

 

[ruffrecords]

In the mid 1970s I attended a Decca recording of Faure's Requiem performed by Kings College choir in Cambridge. We were in a modest back room of the church. They used four mics. A basic Decca tree and a spot mic for the soloist. Mics were fed to a Neve Kelso. Direct outs went to a 4 track Studer and a live mix to stereo went to a 2 track Studer. The recording is still available if anyone wants to hear a genuine Decca tree.

Cheers

Ian

 

[Emmathom]

In the mid 1970s I attended a Decca recording of Faure's Requiem performed by Kings College choir in Cambridge. We were in a modest back room of the church. They used four mics. A basic Decca tree and a spot mic for the soloist. Mics were fed to a Neve Kelso. Direct outs went to a 4 track Studer and a live mix to stereo went to a 2 track Studer. The recording is still available if anyone wants to hear a genuine Decca tree.

Cheers

Ian

Hi Ian, of course I'd be pleased to ear that work ! Thank you for sharing a link

 

[k brown]

In the mid 1970s I attended a Decca recording of Faure's Requiem performed by Kings College choir in Cambridge. We were in a modest back room of the church. They used four mics. A basic Decca tree and a spot mic for the soloist. Mics were fed to a Neve Kelso. Direct outs went to a 4 track Studer and a live mix to stereo went to a 2 track Studer. The recording is still available if anyone wants to hear a genuine Decca tree.

Cheers

Ian

The Ravel Sheherezade with Crespin is another 'Tree and little (or nothing?) else', that's absolutely spooky in it's spacial presentation. Engineered by James Lock, who's said it was one of the highlights of his career.
Only the Ravel and Berlioz selections - the rest were other sessions done elsewhere by someone else; quite different sound.
https://www.amazon.com/Berlioz-Nuits-Sheherazade-Debussy-Poulenc/dp/B00000JXZ4

 

[cfanzalone]

Beautiful masterful recording!...Yep, Very well put: "Tree and little (or nothing) else"...I bothers me so much to see modern mic setups for orchestras with at least one mic over each section, essentially 'close-micing' everything! That's not the way the listener hears it! ...and you're begging for phase and noise problems. Oh, I forgot to say earlier that Decca had many 'divisions', each utilizing the 'tree' but with different mics, yes KM56's, different spacing, etc, etc, that's why I specifically reference 'London Decca'. I also re-iterate that experimentation needs to be exercised...each mic array has the same as a med "Benefits vs. Risks"...LOL but true and for those that panic with the terminology and practice (Coincidence stereo, Spaced stereo, etc) it's really not that difficult!! Use your ears, as there is no 'perfect' array...Actually, I find it fun to experiment!

 

[k brown]

Many misconceptions regarding the Decca Tree were put to rest by the publication of this book, co-authored by one of Decca's engineers, John Dunkerley:

https://www.amazon.com/Classical-Re...21&sprefix=classical+recording,aps,247&sr=8-1

 

[jeremynothman]

Well, I don't think that anyone can give you advice as to what to keep if you have money problems or want to get rid of geat, but I think it's impractical to try only have two microphones for all situations.
Realistically, two cardioids and two omni SDCs are a much better choice for classical music, and if you're also keeping your two your two LDCs, then you're prepared for more situations.