I've been recording my Martin dread with a single KM184 but have been thinking two-mic techniques to get a "bigger" picture of the guitar's sound. One option is to get another KM184 but it wouldn't be a "matched pair". Does that make much of a difference? Any thoughts regarding recording with 2 SDs vs. one SD and one LD? Thanks!
How critical is it that a pair of SD's be matched?
- Thread starter PDXSmitty
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CrowsofFritz
Flamingo!
There are no rules. I’ve miced a guitar with totally different mics and have gotten good results.
rob aylestone
Moderator
It matters if you are using a pair at a distance for X/Y or any of the other stereo techniques where differences in frequency response can cause the stereo imaging to shift, but as you are looking at double miking and then blending, it's fine to use very different mics - one that perhaps emphasises the finger noises, and then another than captures a more round sound from the body - best of both worlds. I've got a few mics I use for stereo recordings (orchestras, choirs, churches - that kind of thing, and I mixed up the matched pair years ago. I often think I found the two matched ones but to be honest, I'm not sure!
Hi. That isn't a big issue in reality, even using them in a stereo pair method (X_Y, ORTF etc.)
If you are using Logic Pro you can use "EQ Match " to create an exacting frequency match. Place them side by side face one monitor, play pink noise through that monitor, record both mics for about a minute. Playback one and use EQ Match to measure the frequency profile from it, save it as a reference profile, playback the other mic recording, insert EQ Match, load the save reference profile from the first mic recording, and "learn" the second mic while playing it back, turn off the learn, click match on the right sode and it will create a profile that matches it to the first mic.
You can save it and reload it at any time to match it to the other mic.
Mark them to keep track of which one is the reference amd which one is to be matched.
Check for EQ Match videos on youtube. There is certain to be a few.
Cheers,
Tom eh
rob aylestone
Moderator
That's neat - I'd not heard of that. I'll certainly read up on this - sounds very useful.
Also a great tool for finding out the true profile of all your rmics.
You can line them all up (if you have enough inputs), record the pink noise playing back through the monitor, include a measurement microphone recording, use the measurement mic as the reference for the rest of the mic's.
The right hand slide for the amount (%) of applied matching can also go negative just to view the true profile of the mic in question.
You can also smooth out the correction for an average.
Very handy and it is always followed by me saying "oh yea that does sound a little..."
It certainly a lot more useful than the frequency response graph they send with the mic.
You can line them all up (if you have enough inputs), record the pink noise playing back through the monitor, include a measurement microphone recording, use the measurement mic as the reference for the rest of the mic's.
The right hand slide for the amount (%) of applied matching can also go negative just to view the true profile of the mic in question.
You can also smooth out the correction for an average.
Very handy and it is always followed by me saying "oh yea that does sound a little..."
It certainly a lot more useful than the frequency response graph they send with the mic.
keith.rogers
Well-known member
Well, it's not "EQ", but *sensitivity* that can create the problem of image drift, depending on what you're recording and the distance, at least that's my take.
My example was a violin-viola duet. They have a fair amount of overlap in range, and if you're not close micing, but trying to primarily capture them separately with mics that do not have similar frequency and polar plots, the (sensitivity-"infected") bleed is in the track where you don't want it, possibly masking the instrument you do want, and EQ is not going to fix that. Imagine a bluegrass band playing in front of a single mic, and every time the fiddler plays on the A-string they take a step forward. (Admittedly, had I known about this ahead of time, I would have changed the mic placement!)
Relatively close or a single source (i.e., not widely spaced over a grand's strings) should be less of an issue, if any at all.
Really, like all mic choices, for me, it's what do I pick to make my life easier when it's time to mix. These days, I choose a pair of SDCs that are known to be alike. (Especially since I have sold my two "one each" SDCs, though I could, at least now, choose one SDC from each pair. But, I would not do that.)
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Well that is a deep dive for certain.
Two mics of the same model, 84's or 184's. That's was what the poster was asking about. I believe someone else may have mentioned different mics?
Same model equals same structure, body, cage, and screen. The element that can change and the manufacture claim to "match" as close as possible is the diaphragm.
I believe you will find the physical design effect will swamp the 3D plot polar sensitivity, not the diaphragm?
I encourage you to try Eq Matching to get to know mic's true response overall, and if you have two of the same model you can place them together in a room anywhere, record anything and do a phase reversal on one to see if you can null the playback (after EQ matching). Then try it with a "Matched Pair" from a manufacturer.
Then you will know for certain.
Cheers,
Tom eh
keith.rogers
Well-known member
Well, I did skip over the part about it being two of the same mics ...
...
Farview
Well-known member
The answer to the question is "it depends"
If you are stereo micing an acoustic guitar and you want the most accurate representation of what it sounds like in the room, matching will be better.
If you are mixing the body and the fretboard to capture the two different sounds, then combining them, it's not as important. (Even if you pan the mics to make it "stereo")
I would only worry about matching if I am distance micing a space, trying to get an accurate picture of what is going on.
I don't worry about it if I am close micing something. If it is a big instrument, like a piano, I will use the same model mic, but not worry if it is matched.
This is a rule of thumb that I made up myself, ymmv.
If you are stereo micing an acoustic guitar and you want the most accurate representation of what it sounds like in the room, matching will be better.
If you are mixing the body and the fretboard to capture the two different sounds, then combining them, it's not as important. (Even if you pan the mics to make it "stereo")
I would only worry about matching if I am distance micing a space, trying to get an accurate picture of what is going on.
I don't worry about it if I am close micing something. If it is a big instrument, like a piano, I will use the same model mic, but not worry if it is matched.
This is a rule of thumb that I made up myself, ymmv.
mjbphotos
Moderator
I've tried any number of 2-mic methods with different mics - LDCs, SDCs, dynamics, and I usually fall back on using 2 LDCs, one at the 12th fret, the other at the lower bout, both about 6" out. When the guitar is the solo instrument in (part of) the mix, I will pan one mic left 15-20%, the other right 15-20%. I may shift both over to one side a bit if other instruments get added to the mix (like piano), so one could be at 30L the other centered. And if there are other guitars in the mix, I will usually decrease the width even more, one could be 30L, the other 20L
(BTW, I do not like hardpanning, so YMMV).
(BTW, I do not like hardpanning, so YMMV).
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HI Keith. I started a new post that has Match EQ used on two mics that are the same model but made at different times and not factory matched, just my random pick of two (I have six of them).Well, I did skip over the part about it being two of the same mics ...
I played a sample track through one monitor and recorded it on both of the mics.
I put up samples of the original track used, matching one mic to the original track and a sample matching one mic to the other.
Cheers,
Tom
Hi Rob,
I started a new post that has Match EQ used on two mics that are the same model but made at different times and not factory matched, just my random pick of two (I have six of them).
I played a sample track through one monitor and recorded it on both of the mics.
I put up samples of the original track used, matching one mic to the original track and a sample matching one mic to the other.
Cheers,
Tom
You can find the best match Rob by putting two mics as close together as possible and flipping the phase of one whilst recording a distant, .2mtr say sound.
Dave.
keith.rogers
Well-known member
Why 2m? Doesn't that add a lot more room into the capture, which, however close the mics are, will potentially color (colour
) the result?I don't know how "factor matching" works but the one pair I have that are supposedly matched came with frequency plots that are so close to identical I had to question if it was a mistake. Admittedly, the factory plots are 1/3 octave smoothed, but I guess while that's a lot of smoothing, visually, it also correlates to how much difference the human ear can detect.
I would wonder if phase/polarity switching, which is not smoothed at all, would cause us to think things are poorly matched, when we would not really hear much difference in actual recording. Or, would the human ear limitation work on that in the same way?
When you flip the phase on one they should null (no sound) if they are matched in intensity at each frequency. It's used all of the time to match gain levels on interfaces before starting to record. I do it on stereo pairs before recording and to check that drum mics are in phase.
In reality it works best at lower frequencies (there is a huge reduction) while higher frequencies by their nature will not effect the mic's as closely.
Also I believe ECC83 said .2 meters which would take the room out of it?
In reality it works best at lower frequencies (there is a huge reduction) while higher frequencies by their nature will not effect the mic's as closely.
Also I believe ECC83 said .2 meters which would take the room out of it?
Here is what CAD says their M179 looks like in Cardioid mode and what I measured it at compared to a measurement mic with pink noise as the source.
I smoothed mine so it is comparable. The peak around 3500 hz looks similar but where they indicate another at around 6500, I have a slight dip??
Some other manufactures plots match much closer to what I measure, but all manufactures are smoothed a lot.
I smoothed mine so it is comparable. The peak around 3500 hz looks similar but where they indicate another at around 6500, I have a slight dip??
Some other manufactures plots match much closer to what I measure, but all manufactures are smoothed a lot.
Two ish mtrs so that the mics are immersed in a diffused sound field and slight dimensional or directional differences will not matter.
Dave.