When to use condenser microphone's low cut switch

Personally I would leave the low cut off. You can always adjust it in Sonar afterwards.

For me the default is to have the filter engaged. Turning it off is the exception and needs some justification. it usually comes down to two factors: what's being miked and how far it is from the mic. 
 
If the miked instrument contains no useful low frequencies, then the decision is easy. Acoustic guitars, most brass instruments, strings, hand percussion, electric guitars, snares & overheads - none of these things benefit from capturing very low frequencies. All of them are going to HPF'd in the mix anyway.
 
If it's a human voice, the filter should always be on, IMO. There is never any need to pick up anything below 80 Hz. Those low frequencies are always going to be extraneous noises, pops and proximity-effect woofs. Sure, you can filter them out after the fact, but if you're recording through a compressor you'll definitely want to remove them at the source. They may also determine how much gain you can get from the mic pre, since a low-frequency pop can easily have twice the energy of the main vocal and cause unexpected clipping.
 
If a microphone had a fixed low-cut filter that I couldn't turn off, I'd be OK with that 95% of the time.
 

bitflipper
If it's a human voice, the filter should always be on, IMO. There is never any need to pick up anything below 80 Hz.

 
Unless you are recording Barry White.
 
Yeah, I tend to leave the filter on. You don't need the low end noise. I still tend to HP the tracks.

Case by case basis, depending upon the instrument - and room.  As stated above, most instruments and vocalists not named Barry don't produce anything below 80 Hz, although the switch may have some effect above that frequency.  Room noise, rumbles and bass build-up in the room can all require the switch.  Piano, no, usually.  Honkeytonk, maybe.

Thanks for the suggestions.
 

rumleymusic
How are you planning on recording the piano, what style of music?

It's a classical piano solo graduation performance - a baby grand in a moderately damped room (carpet and wall curtain) with about 100 seats. The room is relatively nice for music, except I'm worry about audience noise level. Last time when I did a recording, my camcorder picks up loud claps and cheers.
 
This time, I shall be using a Tascam DP 24 portable recorder with 2 condenser mics pointing inside the piano lid - recording it clean (merge the audio with the video later). I'm thinking of placing the mic closer for better stereo imaging and to reduce audience noise - not sure if it's good idea till I test it out. I might add a third mic to pick up the room ambient.
 
So, a solo piano performance seems to suggest recording it flat (no pad) ? I can still roll it later with Sonar.

I guess I didn't read the subject... I thought it was asking about pads...
 
:-)
 
... probably because I've been thinking about pads and mics.

LpMike75

bitflipper
 Sure, you can filter them out after the fact, but if you're recording through a compressor you'll definitely want to remove them at the source. They may also determine how much gain you can get from the mic pre, since a low-frequency pop can easily have twice the energy of the main vocal and cause unexpected clipping.

Exactly.

 
Thanks. I'm shall be doing a test recording on the classical piano earlier on that day. It's going to be recorded clean, no effect, directly into the Tascam DP 24 (and later mix with Sonar).
 
I'll check both setting and come up with a decision then. Since the Tascam can record up to 8 tracks at once, I might add a mic (mono) with the opposite setting for safety.. not sure if it's a good idea, but I think it won't hurt to experiment.