Topic: Logical Upgrade from SP-CMC-4U

[vantheman]

Side note: I am a huge proponent of the Line Audio mics pillowman recommends, but I would caution against using them if your mics will ever be within a few feet of a wall or a ceiling such as shown in your picture. They are subcardioid (halfway between cardioid and omni) and pick up quite strongly from the sides. I found this out the hard way recording vocal tracks in my basement with a CM3 boomed overhead. There were all kinds of early reflections from my untreated ceiling in the recording. These mics also need to be spaced wider than cardioids for proper imaging, so your rig will take up a wider space.

My understanding of the CM4s is that they aren't true subcardioids. The product description calls them "slightly wide". I'm not presently equipped to go any wider than DIN/ORTF...

[aaronji]

Make sure to engage the pad on the Tascam if you are recording loud rock concerts!

[Gutbucket]

Congratulations! The upgrade path you've chosen by way of this thread is a good and logical one based on what and how you are recording.

My comments below are based on the following posts-

I’ll be set up in DIN/ORTF when I can get DFC, otherwise I’ll go XY at 110 degrees PAS.

My understanding of the CM4s is that they aren't true subcardioids. The product description calls them "slightly wide". I'm not presently equipped to go any wider than DIN/ORTF...

The most important part of the gear chain is the microphones, but the most important aspect of the entire recording endeavor is your recording location, and along with that the microphone configuration used, which dances hand-in-hand with recording location.  My suggestion is to put thought into those things, as small improvements here can produce significant improvements in the quality of the recordings with little to no additional monetary cost.

You may or may not be able to improve your recording locations.  Even though this is the most important variable of them all, it is often constrained by practicality, permission, venue, and social constraints.  But think creatively about it, because of all the variables over which we exercise some degree of control, this one has the most potential for making superior recordings.

In contrast, we have a significant control over microphone configuration, and can relatively easily adapt that to best suit the recording location.  For this reason I suggest a mic bar that allows you to adjust the spacing between the microphones as well as adjustment of the angle between them.  The solution might be two adjustable mic-bars: one wide, one narrow, or a handful of 3-printed ones that you can choose between, as those tend to be non-adjustable.

So then, what stereo microphone configuration to use for what location?  You will do well to try the Improved Point At Stacks technique, which automatically reconfigures a stereo microphone pair arrangement based on the geometry of the recording location, optimizing for both clean direct-sound pickup and good stereo imaging.  It's relatively simple to implement in practice- stake out the best recording location you can manage and point the mics at the PA stacks, measure the angle between the microphones, and consult a little table to determine the spacing to use between them.

The technique aims to get the clearest sound possible from the PA and stage, which can be especially helpful indoors and in rooms that are less than ideal, and will keep those somewhat wider-pickup pattern microphones focused on the sound of interest arriving from the front.  The essence of the technique is this: As the recording position is shifted farther away from the stage and PA, the angle between microphones becomes narrower, and as that angle becomes narrower the spacing between microphones should be made wider to compensate.  This is likely to require a wider mic-bar than you currently have for many scenarios, and when recording from a significant distance the spacing becomes rather large. 

Even if not following it's recommendations exactly, it remains a good general rule of thumb for improved recordings.

You can find more information on what, why, how to measure the angle, as well as the tables below in this thread: https://taperssection.com/index.php?topic=167549.msg2087409#msg2087409

Here is a simple example of the table:


And here's a more detailed one:

[vantheman]

Hey Gutbucket, thanks so much for that reply. I’ve seen your improved PAS technique but just now I sat down and finally took the time to understand it. I get it now.

I’d love to have the kind of mic bar you mentioned but I haven’t been able to find one - at least a sub $100 one. I guess I’d want one with rulers for distance and protractors for angle.

[pillowman]

If someone is intetessted into some Line Audio CM3 Samples I've recorded some concerts
Over the last weekend with

PCM-M10 > Denecke PS2>2x CM3s

Or

PCM-A10>Denecke PS2>2x CM3s

Just let me know,
Pillowman

[Gutbucket]

Hey Gutbucket, thanks so much for that reply. I’ve seen your improved PAS technique but just now I sat down and finally took the time to understand it. I get it now.

I’d love to have the kind of mic bar you mentioned but I haven’t been able to find one - at least a sub $100 one. I guess I’d want one with rulers for distance and protractors for angle.

I don't find that necessary. I estimate the angle of the PA and stage by squinting at my balled fist held at arms length - which covers right around 10° of  arc - adding up how many fists it takes to span the apparent space between the PA speakers as viewed from the recording position, then pull out a cheapo tiny dollar store tape measure.   If you practice a few times by measuring some known angle with the fist method, you'll find you can get pretty close.

Attached are the result of a web search for "mic bar" I just made which returns a bunch of relatively inexpensive articulating bars which provide adjustable spacing.  With some of these you slide the microphone attachment points along the bar, with others the attachment point slide in slots, but with the simplest ones you simply angle the two arms out toward either side to go wider, more forward (or back) to shift closer, and in some cases angle them inward for close spacing.  One advantage of that type of bar is that there is less bar extending out wider than the microphones.  One disadvantage is that type of bar typically doesn't go as wide as some of the "slide mounts along a fixed bar" types.  The ones with the slots that are not very wide overall don't provide enough width adjustability to be useful for this IMO. 

Consider the first or last in the list below - the folding ones with four mic-mounting points - not because of the extra attachment points at the hinges, but because the outer attachment points are able to span a much greater range of widths, from near-coincident with them angled inward to relatively wide with them angled outward in-line with each other.

[aaronji]

I’d love to have the kind of mic bar you mentioned but I haven’t been able to find one - at least a sub $100 one. I guess I’d want one with rulers for distance and protractors for angle.

Maybe try one of the basic AB bars. Marked every centimeter and 5 centimeters and well made. The price listed is over $100, but nowhere near as expensive as something like a SpaceBar. Those prices probably also include VAT, which, if you're not in the EU, you won't have to pay. Robert is a nice guy, so you might contact him and see what he says.

I have been using one for about 4 or 5 years now and I am quite pleased with it. Angle markings would be nice, but I can live without them.

[vantheman]

I don't find that necessary. I estimate the angle of the PA and stage by squinting at my balled fist held at arms length - which covers right around 10° of  arc - adding up how many fists it takes to span the apparent space between the PA speakers as viewed from the recording position, then pull out a cheapo tiny dollar store tape measure.   If you practice a few times by measuring some known angle with the fist method, you'll find you can get pretty close.

Got it. I tested out your balled fist method last night. I finally understand it. So for the angle of the mics, you are literally pointing the right mic at the right stack and pointing the left mic at the left stack? With this it makes perfect sense why almost any mic bar would work (though I'll go for a long one). I can't wait to try this out.

[vantheman]

I’d love to have the kind of mic bar you mentioned but I haven’t been able to find one - at least a sub $100 one. I guess I’d want one with rulers for distance and protractors for angle.

Maybe try one of the basic AB bars. Marked every centimeter and 5 centimeters and well made. The price listed is over $100, but nowhere near as expensive as something like a SpaceBar. Those prices probably also include VAT, which, if you're not in the EU, you won't have to pay. Robert is a nice guy, so you might contact him and see what he says.

I have been using one for about 4 or 5 years now and I am quite pleased with it. Angle markings would be nice, but I can live without them.

I have passable-to-decent 3D design skills. This seems like the kind of problem that could be solved inexpensively with a 3D printer. Perhaps we can chat privately about the features that something like this could have. I'd be happy to to share the design with you all.

[Gutbucket]

Got it. I tested out your balled fist method last night. I finally understand it. So for the angle of the mics, you are literally pointing the right mic at the right stack and pointing the left mic at the left stack? With this it makes perfect sense why almost any mic bar would work (though I'll go for a long one). I can't wait to try this out.

Yep.  Pointing the mics right at the PA is the easiest part, and it is that arrangement which maximizes direct-sound pickup in comparison to pickup of reverberant sound and reflections, providing as much clarity as possible from that particular recording location.  In practice it often makes sense to point at the outside edge or just outside of either PA stack if the angle is relatively narrow, making the most of whatever intensity difference there is between the two.  You'll develop a preference for what you find works best in the places you record, and remember- directional mics aren't directional in the same way as laser beams - its more a general trend of sensitivity falling off for sound arriving from directions other than on-axis to each microphone.  Adjusting the spacing based around whatever you determine to be the appropriate angle is the "dialing everything in" optimization part of the process.

Even if you don't have a bar that allows you to set the optimal spacing, or choose to run some other configuration for whatever reason, it's still helpful and informative to go through the routine of measuring the apparent angle between stacks and figuring out what the optimal PAS spacing would be for the microphone pickup pattern you are using, because by doing that you'll develop a gut-feel for the optimal angle/spacing relationship using that pattern.  In that way, you'll also develop a feel for how alternate setup arrangements might sound in comparison.

[voltronic]

Folks, I think we are sorted. My compact open rig consists of: 2 Line Audio CM4s and 1 Tascam DR-100MKiii. Thanks so much for all your help, I think this rig will serve me quite well. Hope to take it for a spin later in September, pending arrival of the CM4s.

Excellent. You won't need to upgrade that for a LONG time. Check out Team Line Audio (link in my signature) for an idea of what they can do. Here are some things I have recorded with the CM3 (CM4 is almost identical).

Just watch out for those close wall / ceiling early reflections.

[voltronic]

Side note: I am a huge proponent of the Line Audio mics pillowman recommends, but I would caution against using them if your mics will ever be within a few feet of a wall or a ceiling such as shown in your picture. They are subcardioid (halfway between cardioid and omni) and pick up quite strongly from the sides. I found this out the hard way recording vocal tracks in my basement with a CM3 boomed overhead. There were all kinds of early reflections from my untreated ceiling in the recording. These mics also need to be spaced wider than cardioids for proper imaging, so your rig will take up a wider space.

My understanding of the CM4s is that they aren't true subcardioids. The product description calls them "slightly wide". I'm not presently equipped to go any wider than DIN/ORTF...

Comparing the polar responses, yes the CM4 does appear to be more toward cardioid than the CM3.

The proof is in the listening, though. Follow posts from Hendricks on this thread to hear proper listening comparisons between the two.

[vantheman]

Comparing the polar responses, yes the CM4 does appear to be more toward cardioid than the CM3.

The proof is in the listening, though. Follow posts from Hendricks on this thread to hear proper listening comparisons between the two.

Would you avoid using these in DIN or ORTF? Thanks for the links too, I’ll listen to those when I get on my laptop later.

[wforwumbo]

Just want to pipe in seconding everything that Gutbucket says. Most important things to making a “better” recording are location, and deploying the microphones you have correctly based on experience and intuition. Better microphones can increase the floor and ceiling of recordings you make, but the wrong mics in the wrong configuration in the wrong spot will produce a recording near the floor of your capacity.

I’d suggest trying your mics in ORTF/DIN to see if you like the recordings made in those formats. They become data points, and you can decide then if you prefer that, or another layout. I don’t enjoy the sound of cardioids or subcards in ORTF when taping live amplified rock music, but that’s my ears and that doesn’t mean it’s wrong. Additionally, if I’m recording an orchestra from over the conductor’s head then ORTF can sound sublime. All this to say, location and deploying the gear in a way that satisfies you is what will make a better recording; learn to identify what it is that you don’t enjoy about your recordings, ask questions and theorize, and continue to adjust your rig and methods over time until you’re happy.

For what it’s worth, I am about halfway between the traditional methods (ORTF/DIN/etc) and PAS theory. I generally prefer my Schoeps in 25-35 cm in varying angles as well as coincident mid-side, and what I use when and where is dependent on where I am as well as what I’m recording. I think the PAS stereo zoom curves are a good starting point, but I prefer using my ears to guide things to generally be more reliant on time difference cues and less on level cues.

“The point of a journey, is not to arrive.” ~Neil Peart