Two ways of spacing mics for stereo recording.
I have recorded a demo CD of my acoustic folk duo. This project has been successful, so much so that a chamber trio I know want me to record them. My own CD was close‑mic'd and overdubbed. This will not be possible with classical chamber music. My question is how to get a 'Radio 3' rather than a 'Classic FM' sound with the equipment I have, or with as little investment as possible. My recorder is a Roland VS880 EX and my mic collection comprises two Rode NT1s, four Tandy/Realistic PZMs, three Beyerdynamic TGX 58s, and one TEAC MC210 back‑electret stereo mic. The room is live, with a wooden floor and big windows. The trio consists of flute, oboe and piano. The piano is an upright, very good sounding and well tuned, and I think this will be the biggest problem.
John Reed
Assistant Editor Mike Senior replies: Most classical sessions tend to mix down to stereo on location, doing a number of takes and compiling the best bits from these after recording. However, I'm not sure how effective this approach will be with your current gear line‑up. My main concern is that the crossfades used in the Roland VS880 aren't particularly tweakable, and this will limit your options when editing stereo classical material. From my own experience of the VS, you ought to be able still to do limited editing, and you'll get the best results using the 2mS crossfade time — I find the longer times tend to dip the overall level at the mid‑point of the fade, and this will probably be too instrusive in classical material, but try them all out and see. Also, it's worth making the general point that you ought to make sure you're in MAS (uncompressed 16‑bit) recording mode — classical musicians are likely to be pickier than most about sound quality.
As for miking up, I'd personally suggest not doing anything much in the way of close miking, if you're after a Radio 3 sound. I'd be tempted to use the Rode mics as my main stereo pair, and then use the Tandys as ambience mics, to be mixed in if required. The Beyerdynamic dynamic mics are probably best left out of this session, as they'll not really be open‑sounding enough for the purpose of classical recording.
Take time getting the sound as right as you can before you record any proper takes — you won't really want to be using the VS's processing or effects afterwards, if you can help it. If the sound is too dry, move the main pair of mics away from the musicians a little, or try fading in the ambience mics a little. If there are problems with the room in general being too live, you could try drawing the curtains over some of the windows. If the balance isn't right between the instruments, try changing the positioning of the players or the mics, and experiment with opening the lid of the piano. If the balance of the players isn't right in certain sections of the music, your only real remedy is to discuss this with the musicians and get them to retake that section. Once you've started doing takes, be careful not to change the miking setup, as you want to be able to edit different bits together and you'll therefore need them to match in tone as exactly as possible.
Stereo miking isn't really my forté, so I can't really recommend which of the available stereo miking techniques would be best (but see Hugh Robjohns' comments, next).
Technical Editor Hugh Robjohns adds: Where Mike mentions not altering the mic setup during recording, I would also add the same about the balance of the mics — any changes make it impossible to edit different takes together.
Regarding which stereo mic technique to choose, you could use the NT1s as either a spaced pair (try angling them outwards about 100 degrees to each other and spaced about 18cm apart), or as a coincident pair (90 degrees mutual angle with the capsules mounted one above the other for vertical coincidence). The latter should give better imaging, but the former often sounds more pleasing and natural to many musicians' ears.
I'd stick with the NT1s as the main pair and experiment with altering the positions of the mics relative to the musicians (or vice versa), as well as trying the musicians in different places in the room, and relative to each other. It takes time to do, but pays dividends in the final results. If the best position for the woodwind results in the piano losing some definition, you could try using the tiniest hint of the Tandy mics on the piano to bring back a little definition and focus.
You obviously have a room arranged already, but for others interested in doing the same kind of jobs, I find the key is locating a venue with a suitable acoustic, both in terms of reverb and in terms of quietness. A country church is often ideal, if you can sweet‑talk the vicar and offer a donation for the new roof fund!
