How to Mic an Ancient Chinese Instrument

[MarcusH]

Hi

I'm helping to record a mate tomorrow and I'd really appreciate advice on mic positioning and other things.

My friend, John, plays an ancient Chinese plucked stringed instrument called the quin (pronounced chin). It's a kind of zither - but with silk strings. It's mainly a solo intrument, sometimes with voice. It can be played on the lap, but many including my friend use a table.

John records his music using a matched pair of C414 B-ULS. about one metre apart and about one metre away and 50cm higher. These are the left/right stereo channels. Here's a photo of the mic positioning:



The issue is that since the instrument is so quiet, John is using a lot of gain and getting a lot of hiss - and the instrument's volume is so low that it's competing with the background noise - even in John's sound proofed room. John doesn't want to move the mics and closer because he doesn't like the close-mic'd sound.

I do think we we should try and move the mics bit closer for more gain and a better signal to background noise ratio. I was also wondering about John's mic positioning - and thought I'd try the X-Y crossed-pair mic technique, using a stereo bracket that John has. The rationale for this is guesswork along the lines of:

1) that's what successful engineers do with guitars
2) It pre-empts phase problems
3) It locks the mic configuration so if we find a good position we can 'lock it off'.
4) it's easier to move the mics backwards and forwards for optimal equidistant positioning.
5) John is getting greatly differing levels between mics with his current set-up.

Mic wise, I was thinking of using the 414s in cardoid or hyper and using the 75Hz high pass filter (Is that the true corner frequency? Much further up and it will be detrimental to the sound of the instrument itself)

Any comments? Is there a downside to moving the mics closer? Do you get more clicks and finger noise?

Cheers

Marcus

[RegressiveRock]

Leaving aside the temptation to say that you ought to try an ancient Chinese mike!

Going closer will get you more playing sounds, but this is not necessarily a bad thing. It depends on what type of performance you are seeking to capture.

Reg

[Exalted Wombat]

It's difficult to get around the basic fact that micing further back will require more gain and pick up more room (both ambience and unwanted noise).

Perhaps it would be better to analyse what he doesn't like about the close-miced sound and see if it can be modified.

[artifus]

quiet mics, quiet pres*, but, most importantly imho, mic positioning (taking into consideration polar response) and acoustic dampening (regarding the acoustic environment you are recording in) - particularly in an unattractive acoustic space.

absorbent materials - blankets, quilts, acoustic tiles, etc, in conjunction with some reflective surfaces arranged around the sound source and mics, with some experimentation, should yield acceptable results.

*not a prob with modern gear, even 'pro-sumer'

[. . . Delete This User . . .]

what pattern is he using currently, omni might not be the best choice for the quieter source, and the array looks like he might have been trying spaced omnis.

and if he's not, are you SURE the mics are pointing the right way??? (i've seen experienced engineers make that mistake, having been using omni, and switching to cardioid without checking the mic's orientation... )

and it's difficult to tell how "on axis" the mic's are.... they look tilted a little, but possibly not enough to be making the best of the available sound...

best plan may be to identify how the thing radiates sound... and then look to position the mics accordingly ,

i've recorded a bunch of relatively quiet sources with the 414 (inc the ULS) , and really.... i've not had any major problem with sensitivity.... and noise....

moving too much closer will affect the sound , , try and work your way around it looking for a sweet spot for a single mic .....

then worry about multi mic options.

[MarcusH]

Thanks folks. Some really good thoughts.

I don't think the mics are pointing the wrong way (The logo and polar pattern is pointing towards the sound source; high pass filter setting on the back.)

Yes maybe the answer is to mic close and then insert the ambience after. I was thinking along those lines recently but then I made a mistake by using a UAD EMT 140 Plate plug-in. Which meant of course that it sounded exactly like a Bruce Lee film .

So I think a little stereo 'ambiance' delay is probably the way forward.

Regarding the polar pattern, I was thinking of either cardioid or hyper.

[artifus]

always worth checking out possible local recording venues - your local church, village hall, school, etc - often available for a few hours in exchange for a small donation towards upkeep.

[. . . Delete This User . . .]

the tone from the instrument will change as you move closer....

Imagine , if you will that you are standing with your nose pressed hard up against a very large brick wall. and you open just your right eye.

all you can see, is the brick right in front of you, and possibly not even all of that.....

if you take half a step back... all you can see is maybe a dozen bricks.... and you may notice some are slightly different shades to others....

take a further step back, and you can see a fair few bricks now , some are definitely different colours, and there seems to be some sort of pattern involved.

take two steps further back, and you can see that there is not only a pattern, but it's a letter... , and that there seem to be more either side of you.

take three steps further back, and you can just about make out a word.... O F F.

at this point you have 2 choices.

take another half step back and open your left eye....

or at take 2-3 more steps back and stick with one eye...

BACK OFF is the message on the wall....

much the same happens with sound....

a rule of thumb, is to start with a mic about the same distance away from a source, as the source is along it's largest dimension....

and start looking for a sweet spot where you hear the best balance to tone from the instrument, coupled with the contribution of the room,.

this is only a rule of thumb, and there are always exceptions to rules, even of thumb.....

but it serves very well as a starting point

finding a sweet-ish spot, is then a good place to be thinking about coincident pairs... and rotate them around a little , looking for the best balance....

bear in mind , for sensibly sized instruments, that you do NOT WANT to be hard panning the pair... if realistic presentation is the desired outcome.... you want to pan them so the image "sounds" about the same size in the stereo field , as the actual instrument.... this usually means Micro-panning in the case of hand held solo instruments....

the point of using a stereo style array, is often not so much to produce a wide stereo image , but to capture all the tonal nuances, using mics pointing at different bits of the source....

the mistake most people make is to immediately start by panning things....

DON'T

look for the best tonal sound with both mics panned centrally....

then start adjusting the width to get the depth of realism in the sound stage.

[Bob Bickerton]

I'm guessing he's using a spaced omni technique, though you haven't mentioned what polar pattern he's using at present. Spaced omni is a technique I'd use in a very good acoustic and the pace doesn't exactly look like a Cathedral!

So yes, consider cardioid or hypercardioid.

John Willet has often posted diagrams of the frequency response of instruments and how they change depending on angle of incidence. I'm sure there's no diagram for a 'Quin' but the lesson there is that it's likely to vary considerably depending, not only how close you are, but also the angle you're listening from.

So the only approach really is to don a good set of headphones and thoroughly explore the instrument.

You then need to decide if you want to reproduce is in mono, accurate stereo (say using X/Y) or explore alternative stereo miking (as per how some people mic a a guitar with one mic over the lower bout and another over the fret board).

If the instrument is at a similar level to the ambient noise floor, then you'll need to move closer (but this may be helped by switching from omni, if they're in omni).

There are quieter mics than those old C414s around, but it should be workable.

Bob

[4TrackMadman]

I will try some combination of a guitar piezo sensor pickup, hopefully something that won't require modification of the instrument, like these stick on shown here:
http://uk.ask.com/wiki/Pickup_%28music_technology%29#Piezoelectric_pickups

and combine that with a condenser/s, mix and balance, shoot for getting attack from the piezo and getting ambience from the condenser/s .

There are also some specialist violin, cello, drums small condenser mics - might want to try these.

Like this one:
http://www.dv247.com/microphones/akg-c-411-l-acoustic-pick-up-miniature-microphone--3320

That instrument looks pretty much like a dulcimer btw

[MarcusH]

Well I've been recording at John's place and it went rather well!

Using the stereo bracket, I put the mics in an XY configuration (listening for the good spots in dual mono first). The close mics really helped increase the volume and reduce the hiss and background noise - but I suspect that using my Apogee Duet played a part too. John wasn't too troubled by the close mic sound.

Interestingly, John's instrument has the sound holes underneath - so the sound seems to be escaping from beneath and sort of bouncing off the wooden table. Thus far, my favourite mic position is sideways, half pointed at the instrument; half at the table.

(By the way, what headphones do you use for finding the sweet spot? My DT100s were too dull and My K701s let in too much ambient sound. Does one need another pair of closed cans for this?)

Anyway, I began to mistrust my judgement after a while. But it was only a technical session, so I took two minute samples from each of the positions I liked (and a couple I didn't) and John and I will review these in my studio, on my monitors, next week.

Thanks for your help everybody. Impressive advice - and a very interesting experience of 'real' recording, for someone who usually only makes R&B out of the box and only records solo singers.

Strange 'reverse coincidence', but John is leaving Mumbai in a couple of weeks and going to live in Singapore! I expect I'll be helping him remotely with post recording processing and I may be asking for your help again then.

Cheers

Marcus

[ROLO46]

Closed cans for recording,HD 25II's for me, also new Sonys ZX700's, v good value, and worth a try, though sweaty after velour Sennys
Open cans for post
The instrument is on a solid table, treat it as a piano, either pop style ,close spaced omnis or classical MS pair within the critical distance.
Sensible pre essential,that portable is not man enough, Duet Yes.