If only two mics... ?

[emrr]

The Oktava MK-012 hyper is their best capsule; very flat response, even off-axis. It's pattern is a bit odd, though; rather closer to cardioid, but not supercardioid either . . .

Ya know, NOW everyone is saying that, but for a solid 20 years it was the omni everyone thought was best, and I still think so today. I dumped the hypers as fast as I could. FWIW!

 

[k brown]

Ya know, NOW everyone is saying that, but for a solid 20 years it was the omni everyone thought was best, and I still think so today. I dumped the hypers as fast as I could. FWIW!

I don't know if they've changed or not, but I got mine as hand-culled matched pairs via the now-defunct Sound Room, about 20 years ago. A pair each of the omnis, cards and 'hypercards', and the hypers were the clear winner as far as flatness of response (the only one of the three which has no lift at the top; that lack of lift leads many to find it dull); and the hypers are far flatter at 180 degrees than the cards.

The flatness at the top makes them excellent for Classical spots.

The omnis are very nice as well, but can be a bit bloated and 'wooly' at the bottom.

 

[emrr]

I don't know if they've changed or not, but I got mine as hand-culled matched pairs via the now-defunct Sound Room, about 20 years ago. A pair each of the omnis, cards and 'hypercards', and the hypers were the clear winner as far as flatness of response (the only one of the three which has no lift at the top; that lack of lift leads many to find it dull); and the hypers are far flatter at 180 degrees than the cards.

The flatness at the top makes them excellent for Classical spots.

The omnis are very nice as well, but can be a bit bloated and 'wooly' at the bottom.

My hypers were from the first stuff brought into the US in 1996, I selected 'best' and 'matched' sets of capsules out of a lot of 30 mics. They were all thin and spikey sounding compared to cardioid and omni. The omni's I use the most by far. Both definitely need HPF or low shelf cut to deal with air movement or handling noise. I do have a newer set of omni capsules from about 2010, pretty much the same as the 1996 sets I have.

The omni's get used on piano on a live broadcast gig, preference of the producer over the MKH20's I used to bring; the particular piano needs some softer wool to his ears, I don't disagree.

I mainly just think it's interesting I'm reading multiple pref for the hyper recently and that was never the case in what I read previously.

 

[k brown]

My hypers were from the first stuff brought into the US in 1996, I selected 'best' and 'matched' sets of capsules out of a lot of 30 mics. They were all thin and spikey sounding compared to cardioid and omni. The omni's I use the most by far. Both definitely need HPF or low shelf cut to deal with air movement or handling noise. I do have a newer set of omni capsules from about 2010, pretty much the same as the 1996 sets I have.

The omni's get used on piano on a live broadcast gig, preference of the producer over the MKH20's I used to bring; the particular piano needs some softer wool to his ears, I don't disagree.

I mainly just think it's interesting I'm reading multiple pref for the hyper recently and that was never the case in what I read previously.

That's really interesting (and a bit alarming) - mine are the exact opposite; buttery smooth, obviously less low end than the omnis but the least 'spiky' of the three, and the least 'spiky' of any SDCs I have. In fact they are touch midrange-y. They're my preferred spots on violin concerti!

They sound pretty much exactly like these plots show, except for having a bit less bump near the top:

 

[k brown]

Here's a clip of a pair of the hypers over drums in the pit orch for a rehearsal of "Follies"; iso of just the Oktavas with none of the other mics mixed. Raw clip; no EQ or processing.



And a bit as mains on orchestra rehearsal, without the omni pair they were finally mixed with, and w/o the reverb that was added. Again with no EQ or processing.



Kind thoughts for the musicians - they were an all-volunteer community orchestra.

 

[ricardo]

Here's a clip of a pair of the hypers over drums in the pit orch for a rehearsal of "Follies"; iso of just the Oktavas with none of the other mics mixed. Raw clip; no EQ or processing.

And a bit as mains on orchestra rehearsal, without the omni pair they were finally mixed with, and w/o the reverb that was added. Again with no EQ or processing.

Thanks for this k brown.

emmathon, if you compare this with the Schoeps Vivaldi excerpt you sent me, you'll note that they have stuff beyond the speakers. Some of this is cos he is using hypercardioids.
You NEVER get this with XY cardioids and only 'some' with ORTF. In a good room, you can clearly hear the soundstage end at the speakers

Your Schoeps ORTF excerpt, though it has nice localisation, it's all 'central'.

One of the beauties of Blumlein with Fig 8s in a good room is the soundstage (especially the ambience) extends beyond the speakers so the speakers disappear.

You might hear some of this 'better' with headphones but I won't pontificate on the difference between stereo on speakers and headphones.

Both sets of recordings, brown's and yours, lack some focus in the centre cos this is well off-axis. Hence the tendency to mix in some 'central' mikes ... and one of the advantages of MS as a two mike arrangement.

 

[Emmathom]

Hi Ricardo

emmathon, if you compare this with the Schoeps Vivaldi excerpt you sent me, you'll note that they have stuff beyond the speakers. Some of this is cos he is using hypercardioids.
You NEVER get this with XY cardioids and only 'some' with ORTF. In a good room, you can clearly hear the soundstage end at the speakers

So what is k brown setup in the second excerpt ? Hypers but which configuration ? ORTF ?

Your Schoeps ORTF excerpt, though it has nice localisation, it's all 'central'.

Well they were set as a regular ORTF 110° angle and ~17cm spacing...

One of the beauties of Blumlein with Fig 8s in a good room is the soundstage (especially the ambience) extends beyond the speakers so the speakers disappear.

So do you advice to use Blumlein when the room is adequat ? my SC1100 LDC in fig8 would be ok ?

You might hear some of this 'better' with headphones but I won't pontificate on the difference between stereo on speakers and headphones.

I've listened with headphones and the stereo is wide (a bit too much ?) and nice

Both sets of recordings, brown's and yours, lack some focus in the centre cos this is well off-axis. Hence the tendency to mix in some 'central' mikes ... and one of the advantages of MS as a two mike arrangement.

Again, do you prefer Blumlein or MS ? I'm a bit lost...

I have a gospel choir (40-60 singers) to record in a medium size church mid January. No musicians, voices only and I'm thinking which setup to use..." Omni SDC pair ? MS (LDC static mics) ? ORTF SDC cardio's ?

 

[k brown]

My purpose in posting the clips was to demonstrate why I was puzzled by @emrr description of the sound of the Oktava hypers he tried being almost the opposite of the ones I got; it wasn't to demonstrate any particular stereo config.

_____________

But, for reference, in the first "Follies" clip they were aimed straight ahead (parallel) at 13", a config I came up with by ear long ago for use in instances where I want to pick up a minimum of the room. In this case I used it to favor the drums in the balance, as when they are part of a full orchestra (as they often are in musical theater), they can get buried by the orchestra.

In the second orchestral clip they were about 10" apart at 90 degrees. They were the middle pair of a Faulkner dual-pair 'phased array', which is a pair of directional mics (any directional pattern can be used) on the same bar as a 26" spaced pair of omnis; both pairs angled 90 degrees. The spacing of the directional pair is selected to produce a stereo image that has the same width as the omni pair. They are mixed so that one of the pairs leads by 3-9dB, depending on the situation. The mix has properties that any single pair can't achieve. Omnis spaced 26" is something Faulkner began using many years ago (most often with M 50s) as an excellent compromise between a fairly accurate stereo image, and a nice sense of bloom and envelopment, especially for orchestra.

Keep in mind too, the distincly odd polar pattern of the Oktava 'hypers' (shown in post #164); they will not behave the same as textbook hypers. As Scott Dorsey has said, they behave more like cardioids than hypers. Since there are no null points, I'm not even sure the rear lobe is anti-phase! But the lack of null points is likely the reason it's off-axis response is so good.

______________

Personally, whenever I use the Faulkner dual-pair array, or the simple 26" AB omnis, I do pan them inward a touch to solidify the center a bit. I, like so many these days, do a great deal of my listening on heaphones, and with hard L/R panning, both these arrays sound a bit 'phasey'; Since the Interchannel Time Difference isn't affected by the panning-in, it still sounds big and spacious on loudspeakers.

 

[Emmathom]

Hi k brown

I read your post with attention... and made a drawing of the configuration you described to be sure I did understood well : a directional pair on the same line with an omni pair (see attached please).

Both at 90° with cardio's spaced by 10" (~26cm) and omnis by 26" (~66cm). I suppose the coupling bar to be at ~10 feet above sources... I supposed too that you advice to use Oktava hypers for their special (and unique ?) behavior in this pattern. I won't be able to use them as I sold my pair a couple of months ago, not satisfied by their sound (in cardio). Btw do you often use them in omni ?

I also did a simulation of the two pairs in the "Faulkner's tool website" (https://sengpielaudio.com/Visualization-Faulkner-E.htm) and it seems that they cover quite the same area and that the positioning of the sources in the reproduced stereo field is quite the same (just a little more spaced with the omni pair).

 

[k brown]

Hi k brown

I read your post with attention... and made a drawing of the configuration you described to be sure I did understood well : a directional pair on the same line with an omni pair (see attached please).

Both at 90° with cardio's spaced by 10" (~26cm) and omnis by 26" (~66cm). I suppose the coupling bar to be at ~10 feet above sources... I supposed too that you advice to use Oktava hypers for their special (and unique ?) behavior in this pattern. I won't be able to use them as I sold my pair a couple of months ago, not satisfied by their sound (in cardio). Btw do you often use them in omni ?

I also did a simulation of the two pairs in the "Faulkner's tool website" (https://sengpielaudio.com/Visualization-Faulkner-E.htm) and it seems that they cover quite the same area and that the positioning of the sources in the reproduced stereo field is quite the same (just a little more spaced with the omni pair).

Yes, that's correct; but only for the Oktava hypers. With less directional mics, the inner pair need to be further apart; Faulkner most often uses the Schoeps CCM21 subcardioids, so they're about 18.5" apart.

The only reason I usually use the Okatva hypers in that 4-mic array is not so much because of their odd paatern, but because of their good off-axis response. Tony Faulkner uses his Shoeps subcardioids most often in this array for the same reason - he doesn't like the off-axis response of typical cardioids.

I use all three capsules of the Okatavs fairly often (I assume that's what you meant by "use them in omni").

When I check the Sengpiel for using the Oktava hypers, I set the pattern to supercardioid even though they're not supercardioid, since they are more directional than cardioid, but not as directional as true hypers, so I figure that's the closest.

 

[ricardo]

First I gotta say the last time I did serious recording was in the last Millenium so take what I say with a pinch of salt. In the end, as various people have said, you have to listen for yourself and if it sounds good, it IS good.

I'll try to explain some of what is going on a bit later to help you achieve what you want.

So what is k brown setup in the second excerpt ? Hypers but which configuration ? ORTF ?

Brown's first arrangement with hypers (or cardioids pointing straight forward is another of Tony Faulkners inventions.

So do you advice to use Blumlein when the room is adequat ? my SC1100 LDC in fig8 would be ok ?

Blumlein Fig-8 is my favourite if the venue is good. But the Fig-8s must be good. I've used Calrec Mk4 Soundfield, TetraMic, AKG C414, the Schoeps CM8 (I think) and also STC 4038 ribbons.

Download some of Aaron Heller's recordings from Ambisonia.com. The standalone VVMic is still available and you can use it to see what 'perfect' Fig-8s, cardioids etc sound like when coincident. The Mk4 Soundfield has 'flat' response in ALL directions including up & down; and TetraMic is not far behind.

I've listened with headphones and the stereo is wide (a bit too much ?) and nice

Like you and k brown, most of the time, I could only use headphones on location. IIRC, there was only I site I used regularly where I could set up decent monitoring speakers. I used to record the same sort of stuff as you guys too

For good stereo on speakers, the headphone sound would have to sound 'a bit too wide'.

Again, do you prefer Blumlein or MS ? I'm a bit lost...

I'm recommending MS cos good Fig-8s are rare and $$$ I've not used the AKG SDC but Paul Hodges on ambisonia.com has and he has recordings using the AKG SDC, C414 and his TetraMic too.

I have a gospel choir (40-60 singers) to record in a medium size church mid January. No musicians, voices only and I'm thinking which setup to use..." Omni SDC pair ? MS (LDC static mics) ? ORTF SDC cardio's ?

You have to choose and listen for yourself. With a choir, precise localisation isn't important so spaced omnis is good. If I had my Soundfield Mk4 prototype or TetraMic, I would use that. MS would be good too. You've probably realised I'm not a fan of ORTF.

---

For stuff outside the speakers, you need sorta out of phase stuff.

Blumlein Fig-8s give you this for the hall sound while retaining good localisation. There is a seamless transition which helps make the speakers disappear.

Spaced omnis give you loads of out of phase but muck up localisation at the same time.

Coincident XY cardioids don't give you any OOP stuff and always sound mono-ish to me.

ORTF doesn't give you OOP stuff at LF but the spacing gives you OOP stuff at HF. But the 'main' localisation cues are at LF so mono-ish but with some nice 'air' at HF. I'll claim it was invented for mono compatibility

I apologise to yus pedants for my Heretical description of these Sacred mike arrangements.

 

[Emmathom]

to @k brown

I can't remember if you participated in my "mic blind test" I posted a couple months ago. There were 2 LDC and 2 SDC involved. t.bone SC1100 mod / DIY 6AK5 / WA84 cardio pair / Oktava cardio pair. The Oktava got the worst comments and arrived in 4th position by most listeners... BUT my pair was old (bought used in 1990) and "lived" about 10 years in a very humid african country without any care so they were probably a bit tuned off (not to say a bit damaged).

I still have 2 bodies with 2 original circuits (where I changed all components but kept the original ones with inscriptions in russian) and 2 circuits from Robert Russell from Russell Technologies : maybe one of these days I'll get a hyper capsules pair (to begin with) and give them a new chance... But no more capsules for now, so can't make tests.

Regards

 

[k brown]

to @k brown

I can't remember if you participated in my "mic blind test" I posted a couple months ago. There were 2 LDC and 2 SDC involved. t.bone SC1100 mod / DIY 6AK5 / WA84 cardio pair / Oktava cardio pair. The Oktava got the worst comments and arrived in 4th position by most listeners... BUT my pair was old (bought used in 1990) and "lived" about 10 years in a very humid african country without any care so they were probably a bit tuned off (not to say a bit damaged).

I still have 2 bodies with 2 original circuits (where I changed all components but kept the original ones with inscriptions in russian) and 2 circuits from Robert Russell from Russell Technologies : maybe one of these days I'll get a hyper capsules pair (to begin with) and give them a new chance... But no more capsules for now, so can't make tests.

Regards

I bought my Okavas and extra capsules from a place no longer in business called 'The Sound Room' around 2004. They claimed to do extensive culling of the mics and capsules and sent the rejects on to other retailers, principally Guitar Center before GC started importing them directly. So there could very well be something to their claims because mine sound quite nice.

I've posted about it here before, but I long ago replaced the circuits in my MK-012s with an adaptation the Nelson Pass' 'B1 Buffer', and use rechargeable betteries to supply the polarization voltage (this is more practical with the MK-012 because Dave Royer discovered years ago that the capsules don't like anything above 45v). I have another pair that I put submini vacuum tube circuits in, but after I found that the B1 bodies sounded just as good, I don't use them anymore.

So my Oktava bodies are no longer stock, but I've heard from people I trust that the early problems with the stock '012 electronics were addressed several years ago.

 

[k brown]

First I gotta say the last time I did serious recording was in the last Millenium so take what I say with a pinch of salt. In the end, as various people have said, you have to listen for yourself and if it sounds good, it IS good.

I'll try to explain some of what is going on a bit later to help you achieve what you want.

Brown's first arrangement with hypers (or cardioids pointing straight forward is another of Tony Faulkners inventions.

Blumlein Fig-8 is my favourite if the venue is good. But the Fig-8s must be good. I've used Calrec Mk4 Soundfield, TetraMic, AKG C414, the Schoeps CM8 (I think) and also STC 4038 ribbons.

Download some of Aaron Heller's recordings from Ambisonia.com. The standalone VVMic is still available and you can use it to see what 'perfect' Fig-8s, cardioids etc sound like when coincident. The Mk4 Soundfield has 'flat' response in ALL directions including up & down; and TetraMic is not far behind.

Like you and k brown, most of the time, I could only use headphones on location. IIRC, there was only I site I used regularly where I could set up decent monitoring speakers. I used to record the same sort of stuff as you guys too

For good stereo on speakers, the headphone sound would have to sound 'a bit too wide'.

I'm recommending MS cos good Fig-8s are rare and $$$ I've not used the AKG SDC but Paul Hodges on ambisonia.com has and he has recordings using the AKG SDC, C414 and his TetraMic too.

You have to choose and listen for yourself. With a choir, precise localisation isn't important so spaced omnis is good. If I had my Soundfield Mk4 prototype or TetraMic, I would use that. MS would be good too. You've probably realised I'm not a fan of ORTF.

---

For stuff outside the speakers, you need sorta out of phase stuff.

Blumlein Fig-8s give you this for the hall sound while retaining good localisation. There is a seamless transition which helps make the speakers disappear.

Spaced omnis give you loads of out of phase but muck up localisation at the same time.

Coincident XY cardioids don't give you any OOP stuff and always sound mono-ish to me.

ORTF doesn't give you OOP stuff at LF but the spacing gives you OOP stuff at HF. But the 'main' localisation cues are at LF so mono-ish but with some nice 'air' at HF. I'll claim it was invented for mono compatibility

I apologise to yus pedants for my Heretical description of these Sacred mike arrangements.

The imaging you get from AB omnis depends entirely on how far they are spaced, plus if, and how they are panned-in. Onno Scholtze shortly before he died was all ga ga about spacings as small as 10-12"; even on orchestra, but it's way too narrow a sound for my taste.

AB spacing any larger than about two feet is where the image get too diffuse, too wide, and a hole starts to open up in the middle. But a little panning-in restores the center perfectly. I've used 3' AB with about 80-82% pan-in with great results - no hole at all.

Lest you fear that doing so would be a mess of combing, a version of the Decca Tree system that Kenneth Wilkinson, John Dunkerley and others in later days of the label, replaced the center triangle with a simple 3' AB pair that was panned-in 50%! With this setup, the level of the outriggers was a bit higher than with the trio of mains. Most of Dunkerley's Montreal recordings were done this way; I never heard a reviewer complain of comb filtering. I believe some of those Dutoit/Montreal releases won engineering Grammys. Also, the Classic Film Scores series on RCA conducted by Charles Gerhardt, engineered by Kenneth Wilkinson used this '4-mic Decca Tree'.

 

[Emmathom]

I've posted about it here before, but I long ago replaced the circuits in my MK-012s with an adaptation the Nelson Pass' 'B1 Buffer', and use rechargeable betteries to supply the polarization voltage. I have another pair that I put submini vacuum tube circuits in, but after I found that the B1 bodies sounded just as good, I don't use them anymore.

I have to look after your old post here on groupdiy... I found N. Pass B1 paper (https://www.passdiy.com/project/preamplifiers/b1-buffer-preamp) and as always his approach is original and worthy. Does it mean that you adapted his preamp to a mic head pre ? Curious to see your schem.
I used to use his "cascade jfet" for my mic pre (external) outputs. A J113 pair by channel set almost as it is showed in Pass' paper. Fed with 15v (see pict of the whole first circuit). Well it worked fine but Thor made me change this for a mosfet output (which is fine too and delivers more current, symetric impedance, etc...)

So my Oktava bodies are no longer stock, but I've heard from people I trust that the early problems with the stock '012 electronics were addressed several years ago.

Yes the quality of the old PCB's was not great

 

[Emmathom]

The imaging you get from AB omnis depends entirely on how far they are spaced. Onno Scholtze shortly before he died was all ga ga about spacings as small as 10-12"; even on orchestra, but it's way too narrow a sound for my taste.

AB spacing any larger than about two feet is where the image get too diffuse, too wide, and a hole starts to open up in the middle. But a little panning-in restores the center perfectly. I've used 3' AB with about 80-82% pan-in with great results - no hole at all.

Lest you fear that doing so would be a mess of combing, a version of the Decca Tree system that Kenneth Wilkinson, John Dunkerley and others in later days of the label replaced the center triangle with a simple 3' AB pair that was panned-in 50%! With this setup, the level of the outriggers was a bit higher than with the trio of mains. Most of Dunkerley's Montreal recordings were done this way; I never heard a reviewer complain of comb filtering. I believe some of those Dutoit/Montreal releases won engineering Grammys.

I must work again on my Vivaldi last recording to check if that "extrem spacing" between omnis (~7 feet) can be arrange by panning them inside, like 70% to 60% but I fear 7 feet was way to much...

 

[k brown]

I must work again on my Vivaldi last recording to check if that "extrem spacing" between omnis (~7 feet) can be arrange by panning them inside, like 70% to 60% but I fear 7 feet was way to much...

Yes, way too much, but you might be surprised by experimenting with panning them in anyway; it can be very touchy - not enough and there's still a big hole, just a bit too much and bam! there's that ugly lump of mono in the middle.

 

[k brown]

I have to look after your old post here on groupdiy... I found N. Pass B1 paper (https://www.passdiy.com/project/preamplifiers/b1-buffer-preamp) and as always his approach is original and worthy. Does it mean that you adapted his preamp to a mic head pre ? Curious to see your schem.
I used to use his "cascade jfet" for my mic pre (external) outputs. A J113 pair by channel set almost as it is showed in Pass' paper. Fed with 15v (see pict of the whole first circuit). Well it worked fine but Thor made me change this for a mosfet output (which is fine too and delivers more current, symetric impedance, etc...)

Yes the quality of the old PCB's was not great

As you can see I didn't change much; mostly just left out the 'HiFi preamp' parts on the left of the B1 schem, increased the resistor to the FET gate to 1 gig.

Shown is how I use it with the Primo EM23, but for the Oktava it's the same except for the required parts for the capsule polarization. For that I use a pack of 5 rechargeable 9v batteries and tap off the 27v for the B1 power. The LiPo batteries I use are 7.4v, so the totals are actually 22.2v and 37v.

The output circuit on the right is adapted from the AT8533 power module (in a remote box) without it's FET biasing resistor, and using the supplied transformer just as a way to tap off the phantom power.

 

[Emmathom]

As you can see I didn't change much; mostly just left out the 'HiFi preamp' parts on the left of the B1 schem and increased the resistor to the FET gate to 1 gig.

Shown is how I use it with the Primo EM23, but for the Oktava it's the same except for the required parts for the capsule polarization. For that I use a pack of 5 rechargeable 9v batteries and tap off the 27v for the B1 power. The LiPo batteries I use are 7.4v, so the totals are actually 22.2v and 37v.

Could you provide your Okatva schem ? Maybe I would be tempted to warm the iron... I guess you deal with the +48v, don't you ? No battery... The capsule polar. can be done with +48v too as the original MK-012 (without DC/DC board)

The output circuit on the right is adapted from the AT8533 power module (in a remote box) without it's FET biasing resistor, and using the supplied transformer just as a way to tap off the phantom power.

Here is the Russell "Schoktava" schem. I don't know (I'm not enough experienced with electronics) if it's good, great, or just so-so. I've build up 2 boards but never tested them... I could be tempted to get 2 hyper caspules (brand new from their online german shop)

 

[k brown]

Could you provide your Okatva schem ? Maybe I would be tempted to warm the iron... I guess you deal with the +48v, don't you ? No battery... The capsule polar. can be done with +48v too as the original MK-012 (without DC/DC board)

Here is the Russell "Schoktava" schem. I don't know (I'm not enough experienced with electronics) if it's good, great, or just so-so. I've build up 2 boards but never tested them... I could be tempted to get 2 hyper caspules (brand new from their online german shop)

The actual build is with only the B1 parts in the shortened MK-012 body, with 15' captive mini quad cable.

The battery pack and output cicuits are in a separate enclosure. The rectangle marked ES945 is the circuit board from an Audio Technica ES945 boundary mic, which is simply an SMD version of the AT8533 power module (with the FET-biasing resistor removed; they were designed for the 2SK660 FET used in many, many AT mics.).

The captive cables of the mics are terminated with 5-pin male DIN connectors, with panel-mount female DINs on the 2-ch power module. One pin for 22v to the FETs, one for polarization from the trafo tap, one for audio, one for ground. The load on the trafo tap pulls the 48 phantom volts down to about 37v.

NOTE: I just noticed a mistake in the schematic; the ground is shown connected to the PMs audio input instead of it's own pin.