Hi Daniel, Thanks for writing. I wasn’t considering the L-R reversal a mic anomaly or issue with any of the Ambisonic software (Harpex, VVMic, etc.). I use Blumlein, ORTF, and mid-side mic techniques a lot in my commercial (music) recordings. Clearly, the lobes of the figure-8 polar patterns cross sides when using the Blumlein configuration. This is of little consequence when capturing an orchestra forward of the mikes or for capturing the natural ambience in a music hall. But when it comes to making “HRTF” or binaural recordings from the popular stereo miking techniques (apart from an acoustical test fixture such as KEMAR), I just wanted to demonstrate differences among the techniques with a simple demonstration. If accurate placement, or perceived sound-source location of sounds emanating from the rear plane is important to a person (or, in my case, hearing research), then an Ambisonic mic (or native miking) is well worth considering. Sounds originating from any direction can be reproduced fairly accurately without loss of directional cues. As you know, it is often desirable in live and studio sound to use uni-directional mics to reject unwanted (rearward) sounds, and virtual mics using B-format files can do this quite nicely, too. While it is known that the off-axis coloration for many “classic” cardiod mics lends to their characteristic sound, I observed that the characteristic sound for off-axis sources when using virtual mics may a bit different from what we’re used to hearing. When people ask which mic technique is best, it really depends on what one is trying to capture--I guess that was part of the message I hoped to convey to readers. I’m really enjoying experimenting with Ambisonics, as this is a new adventure for me. I like to share my experiences, and certainly hope others can benefit from them as well. Kind regards, Eric
________________________________ From: Daniel Courville <courville.dan...@uqam.ca> To: Eric Carmichel <e...@elcaudio.com>; Sursound <sursound@music.vt.edu> Sent: Friday, April 6, 2012 9:44 AM Subject: Re: [Sursound] ORTF, Blumlein, and HRTF files for download Le 12-04-05 14:28, Eric Carmichel a écrit : >With the Blumlein setting and listening under headphones, voices that >originated from the back left appear to come from the right. Similarly, >voices from the back right appear to the left. For sounds originating >from the front, everything is natural and isn't too different sounding >from the HRTF setting. But in a "surround" of sound (to include >naturally-occuring reverberation), sounds from the rear are "off" >(laterally crossed). (...) L-R errors aren't because the B-format files >were in the wrong order (W thru Z). I'm not sure if you're saying that you consider this left/right reversal an anomaly, but it's the expected behaviour when using a Blumlein setup: the rear lobe of the microphone pointing left in front is pointing right in the back. Conversely, the rear lobe of the microphone pointing right in front is pointing left in the back. - Daniel -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20120406/39e564f5/attachment.html> _______________________________________________ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
