Topic: Acoustic Recording Techniques

[Gutbucket]

Thanks for the feedback. I keep listening and sometimes the spread sounds natural to me; other times I think the image is a bit bunched towards the center. Still not sure if I want to do this again, but it worked better than I expected.

I think of myself as someone who's preference leans toward a wide, open portrayal.. as long as the center is sufficiently solid to support it, and doesn't stick out or otherwise sound "disembodied".  I'll try to give a listen with speakers rather than headphones.

[goodcooker]

The composer of the symphonic piece I'd planned to record the dress rehearsal of got back to me finally and the date is while I'll be in NOLA for Jazzfest (the same day I'm recording and live streaming for the Bayou Rendezvous) so that gig isn't going to happen. I thought I'd copy the details he gave me for the sake of discussion. Recording something this size and type is a new thing for me and I'd be interested in how others would approach it.

From the composer - "My performers are going to be set up as an orchestra, I can send you a layout of how the setup is and if we will need any changes for the day if you would like! I will be about the width of 57' and a length of about 25' back give or take. These are very very rough estimates but are close to what it will be. The arrangement will be strings downstage center to the podium, center stage is the woodwinds, then brass directly behind them, and then percussion with timpani up center stage. Piano and Harp will be on stage right behind the violin 1s.

Percussion is a large part of this concert and has some louder moments in the second half of the Symphony and within Stellarium.

To make things easier, I am okay with a single mic for each section (Violins, Viola, Cello/Bass, High Woodwinds, Low woodwinds, High Brass, Low Brass, Piano/Harp/Mallet Percussion, Untuned Percussion, Choral) or how ever you see fit!"

What would you do? Pairs of OM1 omnis, CM3 wide cards, MBHO hypers, ADK LD cards and a AKG C522 cardioid XY stereo mic available to use plus various dynamics. This was to be a dress rehearsal recording so anything goes as far as placement no worry of obstructing sightlines for the audience. Max inputs = 10. I have a Focusrite 18i20 with 8 inputs plus SPDIF that can be run simultaneously to my laptop in Reaper. Neve Portico 5012, W+ and T mod UA5 and Apogee Mini MP available for pres (8 channels total). Since I have to use 2 channels of the Focusrite pres (which are fine but flat and lifeless honestly) I'm not sure where they'd be in use.

[voltronic]

The composer of the symphonic piece I'd planned to record the dress rehearsal of got back to me finally and the date is while I'll be in NOLA for Jazzfest (the same day I'm recording and live streaming for the Bayou Rendezvous) so that gig isn't going to happen. I thought I'd copy the details he gave me for the sake of discussion. Recording something this size and type is a new thing for me and I'd be interested in how others would approach it.

From the composer - "My performers are going to be set up as an orchestra, I can send you a layout of how the setup is and if we will need any changes for the day if you would like! I will be about the width of 57' and a length of about 25' back give or take. These are very very rough estimates but are close to what it will be. The arrangement will be strings downstage center to the podium, center stage is the woodwinds, then brass directly behind them, and then percussion with timpani up center stage. Piano and Harp will be on stage right behind the violin 1s.

Percussion is a large part of this concert and has some louder moments in the second half of the Symphony and within Stellarium.

To make things easier, I am okay with a single mic for each section (Violins, Viola, Cello/Bass, High Woodwinds, Low woodwinds, High Brass, Low Brass, Piano/Harp/Mallet Percussion, Untuned Percussion, Choral) or how ever you see fit!"

What would you do? Pairs of OM1 omnis, CM3 wide cards, MBHO hypers, ADK LD cards and a AKG C522 cardioid XY stereo mic available to use plus various dynamics. This was to be a dress rehearsal recording so anything goes as far as placement no worry of obstructing sightlines for the audience. Max inputs = 10. I have a Focusrite 18i20 with 8 inputs plus SPDIF that can be run simultaneously to my laptop in Reaper. Neve Portico 5012, W+ and T mod UA5 and Apogee Mini MP available for pres (8 channels total). Since I have to use 2 channels of the Focusrite pres (which are fine but flat and lifeless honestly) I'm not sure where they'd be in use.

I'll respond as if you are actually recording this, even though it seems it's no longer possible.

Focus your efforts on main pickup first. That should be getting you 90%+ of your final mix.

There are a few options that could work, depending on the acoustics of the space and the nature of the music being recorded:

1. OM1 main pair, directly behind and above conductor, 12-15 ft high. I usually start with a lateral spacing of 40 to 50 cm depending on the SRA I need to cover. APE spheres can be helpful in getting more reach, but be careful of introducing too much brightness. Vertical angle also has a big impact in this respect. In this situation I would angle slightly down aimed at the percussion section.

2. Faulkner 47/67 array of central CM3 with flanking OM1, width of inner and outer pairs as those numbers specify (in cm) and each pair with 90° opening angle. The two pairs are not usually at equal level in the final mix, but having them both their gives you a good amount of reach to the back of the ensemble. Same position as 1.

3. CM3 in NOS (or same 30 cm width width 110° opening angle) in same position as 1. OM1 as wide flanks, same height and distance from front of stage, spaced 1/2 to 2/3 the distance from center to outer boundary width of orchestra on either side.

//

For spot mics, I wouldn't consider the dynamics at all. Their lower sensitivity and reduced treble response will run contrary to adding fine detail even when low in the mix, which is what the spots are for.

Your MBHO hypers are closest to what the pros would probably reach for as spot mics (Schoeps MK 41 is a popular choice) but your ADK's could work nice as well. I have seen LDCs used as string and woodwind spots above the section and aimed almost straight down. Those could also work well as bass drum and tympani spots.

It's kind of hard to advise on the spot mics without having a close knowledge of the music and what the space sounds like. Like I said earlier, your main pickup should get you most of the way there unless you're in a problematic space or the composer/producer/whoever has unusual requirements for the recording.

[Gutbucket]

So much depends on the acoustics of the hall in which the performance will happen.  A great room makes it much easier to keep things simple.

I'd suggest keeping approaching it like you would an on-stage tape, just a lot bigger! Probably just a main and flanking pair.  Dealing with spot mics is going to be a pain and a hassle.  A good orchestra in a good room is self mixing.  Something like Volt's 3rd suggestion would be a good safe bet.

3. CM3 in NOS (or same 30 cm width width 110° opening angle) in same position as 1. OM1 as wide flanks, same height and distance from front of stage, spaced 1/2 to 2/3 the distance from center to outer boundary width of orchestra on either side.

If there is a choral ensemble, maybe mic that as well, but if arranged immediately behind the orchestra its probably not necessary.

If there is a soloist, use a directional spot on that.

Keep it relatively simple and manageable.

[checht]

Schubert B-flat Major Piano Sonata #21. D960-Plaza Performance Space-Berkeley, CA-December 5, 2023
Performer: Eric Zivian
Instrument: 1820s pianoforte

Recording notes:
1 pair of km41s ORTF, 10"" behind the hammers and 12" above.
Also a pair of MK22s A/B 12" split, aligned with the knee and about 20" out. Height was 4" above the opened lid, both pointed about 65º down and at the soundboard/strings.
A couple pics below illustrating.

It was amazing to stand close and at the knee during rehearsal, eyes closed, listening to the incredible image and sound stage. So different w/out the cross strings of a piano. Really informed my subsequent mixing.

Dropbox folder with aiffs:
https://www.dropbox.com/scl/fo/b64gh1rm394y1ajjzr0dt/h?rlkey=am1vkbr46pv4h80pfw4is8ri0&dl=0

[goodcooker]

Since I posted this he got back to me and suggested that we record his final rehearsal before the dress rehearsal last week of April before I go out of town. So it's back on.

I very much like the approaches that both you guys suggest - relying on the main pair above and behind the conductors head. I'd go with the Faulkner 47/67 plan and hope that it does the job even with the orchestra at 57' wide. Having two pairs to choose from or mix together is what appeals to me the most. Having the other mics set up and recording can't hurt. If the soup needs a little spice it's available and automation in mixing has gotten super easy. Want the strings or percussion to swell? Move the fader.

I'd likely go with 8 total locating two spot mics somewhere in the strings/woodwinds and the other two near percussion since he says that percussion is a large part of the piece. I guess we'll see after he sends me the stage plot and I find out which hall he's rehearsing in.

Kinda glad now that I bought those ethercon snakes when I did and that I ended up with two of them instead of one.

[voltronic]

Schubert B-flat Major Piano Sonata #21. D960-Plaza Performance Space-Berkeley, CA-December 5, 2023
Performer: Eric Zivian
Instrument: 1820s pianoforte

Recording notes:
1 pair of km41s ORTF, 10"" behind the hammers and 12" above.
Also a pair of MK22s A/B 12" split, aligned with the knee and about 20" out. Height was 4" above the opened lid, both pointed about 65º down and at the soundboard/strings.
A couple pics below illustrating.

It was amazing to stand close and at the knee during rehearsal, eyes closed, listening to the incredible image and sound stage. So different w/out the cross strings of a piano. Really informed my subsequent mixing.

Dropbox folder with aiffs:
https://www.dropbox.com/scl/fo/b64gh1rm394y1ajjzr0dt/h?rlkey=am1vkbr46pv4h80pfw4is8ri0&dl=0

Thanks for posting this again. I'm listening closely.

I usually don't like close-miked perspective for classical piano, but this is something totally different. I think what you've done in capturing this fortepiano is really excellent. Without being there in person I can't fully judge, but to my ears it sounds like I am there, listening to this instrument in this room. Bravo!

Did you time-align your two pairs? The reason I ask is I'm not sure if I'm hearing some slight phasiness / comb filtering, or if that's the characteristic inharmonicity of this instrument. Are you able to share a couple samples of just the MK22 pair alone?

[checht]

Great questions! I did time align the 2 pairs; wasn't a lot of difference but enough to make the edit.

I'll post mk22 track later tonight. The instrument was close to a wall to accommodate the audience. We will play with positioning during rehearsal next time.

Glad I didn't blow it. I worked with what I had with me at the end of a rock tour and benefitted from research  and good fortune.

[Gutbucket]

It was amazing to stand close and at the knee during rehearsal, eyes closed, listening to the incredible image and sound stage. So different w/out the cross strings of a piano. Really informed my subsequent mixing.

That's interesting to read as I've wondered about it myself but have never had the chance to really listen like that. 

[Organfreak]

So much depends on the acoustics of the hall in which the performance will happen.  A great room makes it much easier to keep things simple.

I'd suggest keeping approaching it like you would an on-stage tape, just a lot bigger! Probably just a main and flanking pair.  Dealing with spot mics is going to be a pain and a hassle.  A good orchestra in a good room is self mixing.  Something like Volt's 3rd suggestion would be a good safe bet.

3. CM3 in NOS (or same 30 cm width width 110° opening angle) in same position as 1. OM1 as wide flanks, same height and distance from front of stage, spaced 1/2 to 2/3 the distance from center to outer boundary width of orchestra on either side.

If there is a choral ensemble, maybe mic that as well, but if arranged immediately behind the orchestra its probably not necessary.

If there is a soloist, use a directional spot on that.

Keep it relatively simple and manageable.

This third suggestion is the same as works best for me for organ recordings. KM143 in NOS position; DPA 4090 as flanks (pointing left and right at the maximum possible practical distance of 150 cm).
It allows flexibility to move from one pair to the other with everything in beween.

[checht]

It was amazing to stand close and at the knee during rehearsal, eyes closed, listening to the incredible image and sound stage. So different w/out the cross strings of a piano. Really informed my subsequent mixing.

That's interesting to read as I've wondered about it myself but have never had the chance to really listen like that.

In initial playback, I noted that the high/low frequencies were reversed on the 2 stereo tracks. The 41s near the hammers had low freqs on the left, as you'd expect. The 22s were the reverse, with the short high freq strings sounding distinctly from the left, and longer low freqs coming from the right. Somewhat disbelievingly, I swapped the 22 channels, and the sound stage appeared. Still not certain about that choice, but sure sounded incoherent the other way...

[Gutbucket]

This third suggestion is the same as works best for me for organ recordings. KM143 in NOS position; DPA 4090 as flanks (pointing left and right at the maximum possible practical distance of 150 cm).
It allows flexibility to move from one pair to the other with everything in beween.

^ Thinking similarly.. More thoughts on why I gravitate to #3.. more specifically to the wide flaking omni pair aspect of it-

I very much like the approaches that both you guys suggest - relying on the main pair above and behind the conductors head. I'd go with the Faulkner 47/67 plan and hope that it does the job even with the orchestra at 57' wide. Having two pairs to choose from or mix together is what appeals to me the most. Having the other mics set up and recording can't hurt. If the soup needs a little spice it's available and automation in mixing has gotten super easy. Want the strings or percussion to swell? Move the fader.

Regardless of what you choose to use as the main pair or array in the center just behind the conductor, consider including a wide-spaced flanking pair farther out to either side of the main pair. Wide-spaced meaning like 10-12' or so out from the center to either side.  If going with the Faulkner array and using your OM1's in that, maybe use the ADKs in omni for the wide-flanking pair if they are the switchable TLs. 

Here's the reasoning- The addition of the wide-spaced flanking pair of omnis to whatever the center main pair happens to be will serve to hedge the bet in a couple ways. First, it's a relatively traditional setup for orchestra recording with a long history of working well and flexibly.  Secondly, the wide flanking arrangement will sort of serve in a way similar to spot mics in regard to covering/balancing the breadth of the orchestra, but in a way that is more of an extension of the main array rather than in the manner of individual, isolated spot mics. Its more likely make things more easily managed during recording and in the mix without the typical problems of spot mics, and will preserve more natural stereo and depth cues.

The Faulkner array is not a widely spaced on its own and is really more of a single semi-near-spaced array that uses four channels.  It can work very nicely but does not have that same "distributed across the front of the orchestra" aspect to it and is not so much a traditional recording method. Without having used it in this specific situation previously I'd be more comfortable combining it with the wide flanking omnis to increase the odds of everything being covered and working well.

I think it will not only be easier to manage an extended main array type setup than a less-wide main array plus spot mics, I also think its likely to sound better. One advantage of the main array + flanking pair is that the mics are positioned on essentially the same L/R plane, so it's already time-aligned, and it tends to preserve depth cues.  I really like hearing the depth cues of the woodwinds being somewhat farther upstage than the string sections and the percussion behind that.  Its what sounds real to me and is one of the things I listen for from the audience and in my own recordings.  Spot mics tend to flatten the depth cues, which tend to be the first thing to go.  It takes a lot of work to get the clarity from the spot but avoid that flattening effect.  Also, the wider-spacing of the flanking pair will produce a nice big decorrelated reverberant room sound- making a good hall sound big and dimensional. 

If the room isn't great, spot mics might be necessary.  You're then in a way reinforcing and recreating things artificially because the room isn't up to it.  But if the room is good it will be a lot easier and potentially sound better to rely on a well distributed and flexible main array across the front.  There are good reasons for complicating things, but especially as a first orchestral open-recording effort, I'd try an keep things simple without spots except for where they are really be needed.   

Any chance you might be able to attend a rehearsal before the recording date?  That way you can hear some of the work, determine if anything might really need a spot, listen to how the room sounds, and how the sections interact in terms of depth and clarity.

[goodcooker]

I'm recording a rehearsal instead of the debut performance due to contractual arrangements with the concert hall. Going in blind since this is a debut performance of the piece.

I agree that relying on the main array is the way to go. It's how I record most musical performances but the composer has said "I'm okay with a singe spot mic on each section" meaning his expectation is a dozen mics or more. I think the happy medium is 4 mics as main array and 4 spots.

The spots don't have to be mixed in all the time. A little automation can fix the hiccups of imaging when the spots are located 20 feet in front of the main array. Blend a little in when it's needed for immediacy during a passage then fade it back out.

Thanks for everyone's input here it's given me a lot to think about.

[voltronic]

Gutbucket - My experience with the Faulkner 47/67 array is that it does very well in preserving the 'depth cues' you cite, because it was designed as a phased array. Tony Faulkner's term is "forward gain" for how the four aligned mics work together for this effect.

You may have noticed I also suggested the very wide flanks as you did, and you're right that's a much more traditional arrangement. I wanted to also share that the great Onno Scholze would often do this with 4 omnis - a central pair very close (<40 cm) and the wide flanks as you describe. That's definitely non-traditional, as a near-coincident cardioid pair is the typical thing to use in the middle.

I agree with you about the spot mics potentially flattening the image, which is why I only recommend using them if really necessary, and as low a level as possible. Typically when I use spot mics, it's for a choir behind an orchestra as well be the case in a concert in doing in a few weeks.

[Gutbucket]

I don't doubt the Faulkner array does depth well, and it will l probably work fine for this.  I just don't really see it being specifically advantageous for this particular situation if doing so were to require giving up a wider-spaced flaking omni pair.  I sort of see the phased array thing as being a way of achieving some additional forward "reach" without using overly directional patterns (your noting that TF refer's to it producing "forward gain" rings true with my understanding of it).  However, with the freedom to place the main array directly behind and above the conductor, I don't suspect additional forward reach / forward gain is going to be necessary.  But again, a lot depends on the sound of the hall.

I think that Onno S arrangement of a relatively narrow spaced omni center pair placed just above and behind the conductor plus flanking wide omnis may be relatively common these days.  At least two different classical venues I frequent here use that as their main array most of the time.

Mostly I think using less directional mics with spacing across the front will make relying primarily on the main mics more forgiving and increase the chances of the main array providing everything needed.

I agree that relying on the main array is the way to go. It's how I record most musical performances but the composer has said "I'm okay with a singe spot mic on each section" meaning his expectation is a dozen mics or more. I think the happy medium is 4 mics as main array and 4 spots.

Yeah, a lot of that might be expectation based on how he's seen it done in the past.  In addition to the four omni main array I mentioned in us at those classical venues I frequent, a couple of them additionally spot mic almost everything.  Partly that's because they can and it gives them options, in once case because it provides a learning opportunity (a University), in another because is a very "wired" venue that records everything, streams/casts many events and uses the spots in combination with close up robotic camera shots to make relevant auditory zooms that complement the video closeups.

But sure go ahead and do some spot mic'ing too, as long as that doesn't require sacrificing attention to the main array in any way.  I just sort of feel it will be a rather futzy and unnecessary distraction, and you will have plenty else to pay attention to doing this for the first time.  Satisfying the expectations of the composer is of course advantageous for different reasons, even if it's not particularly helpful for the recording.  Part of the composer's job is arranging for the mix of sound as performed by the orchestra, and part of that is the physical arrangement of the instrument sections, which some composers switch around specifically with a specific sound balance in mind. Part of the conductor's job is working the live mix of the orchestra in practice and performance to achieve the composer's vision, and produce a properly balanced sound to the audience.  If those things are all working correctly in the hall, the main mics will do the job without the need for spots!