VCSL

[Samulis]

(04-17-2018, 03:24 PM)Michael Willis Wrote: I ordered another microphone, did some reading about NOS stereo recording technique, and made an attempt at sampling the clarinet. My room still doesn't have any proper sound treatment, so I stood behind the mics and looked down the "line of sight" on each of them, then hung up blankets where the cardoid pickup would be the strongest. I played the instrument about 0.8 meters away from the mics, and had the gain on both of them dialed in at about 60%.

https://www.dropbox.com/s/m8iz33kbo0uomg...7.wav?dl=0

Sam, will you give me some feedback on this? It would be very helpful to know if there are any adjustments I can make that would improve the sampling quality. It occurred to me that I know a lot of people who play different instruments, so I can possibly contribute quite a bit to VCSL if I can get satisfactory recordings.

First off, don't be afraid to record with more gain- ideally the loudest recorded sounds should be around -6 dB or so (so there's plenty of extra space for clipping). Too much lower and you risk introducing noise from the equipment when much gain is added.

I noticed that the two channels were not quite at equal volume. This is a very tricky job when recording with analog/manual gain knobs on the interface. The easiest way to balance two preamps is to have some sort of signal generator (e.g. an electric guitar/piano/etc) that you run into one preamp and play a tone, then take note of the specific volume on the monitoring software/DAW. Then, switch to the next preamp and add or remove gain until it matches the same volume. This should be done when recording with a microphone pair. Note that, especially with cheaper microphones and cheaper preamps, the tolerances and the exact placement of the knobs means less about the actual gain being applied- my Zoom H6 for example (with preamps marked 1-10) differs by almost as much as a number when properly calibrated like this.

I also noticed a drone-like sound in the background, likely a fridge or air conditioning unit. Luckily something like this is easy to remove with a Notch Filter tool (like a super-duper small-bandwidth EQ). Combined with a pass through the denoiser, this gives a very reasonable noise floor of about -80 dB (down from the mid-50's).

I'm not sure what you mean 'behind the mics'? You want to be close to the middle line between where the capsules are pointing.

Anyway, here's the processed version I did if you want to have a listen or a go at cutting them-
https://s3.amazonaws.com/SamulisRandom/s...cessed.rar

Best way to figure out the tone/room sound you want is to try playing the instrument at a few different positions/distances until you come across one you really like. It may be closer or farther than recommended. Also don't be afraid to try different setups, such as spaced pair or ORTF. It doesn't matter how you do it, so long as it sounds the best and has reasonably low noise.