Binaural recording and Acoustics......

[MrChrisos]

Hi all,

I just made my first binaural head, and I'm happily recording away and tweaking the setup as I go, with lots of inspiration on thanks to all the info people have brought to this forum on this.

One thing I've been trying to get right is the warmth of the instruments. I've noticed a lot of my signals are coming through more trebly than I'd like. I'm guessing this is a mixture of distance and tiny diaphragms, but it's something I'd like to improve upon as naturally as possible.

Then I came across that lovely vid just posted by Binaural Mark of the Ottmar Liebert recording - which sounded fantastic. Now I'm sure a lot of the quality is down to fritz, but I couldn't help noticing the smooth clay/plaster walls of the room.

I'm not yet recording in a treated room, but I was wondering what sort of treatment would best complement my tones, if I could use the space for more warmth, and the pros and cons of live treatment vs studio treatment in binaural recording.

Half questions, half opening up a discussion I suppose.... sorry for the long opening post.

[boojum]

The quality of the sound depends upon the space and the mics. You my have to fiddle with the sound in post. The Luna Negra selection may have been fiddled with in post, er, um, been mastered.

[Mark A. Jay]

Originally Posted by MrChrisos

Hi all,

I just made my first binaural head, and I'm happily recording away and tweaking the setup as I go, with lots of inspiration on thanks to all the info people have brought to this forum on this.

One thing I've been trying to get right is the warmth of the instruments. I've noticed a lot of my signals are coming through more trebly than I'd like. I'm guessing this is a mixture of distance and tiny diaphragms, but it's something I'd like to improve upon as naturally as possible.

Then I came across that lovely vid just posted by Binaural Mark (AKA Mark A. Jay) of the Ottmar Liebert recording - which sounded fantastic. Now I'm sure a lot of the quality is down to fritz, but I couldn't help noticing the smooth clay/plaster walls of the room.

I'm not yet recording in a treated room, but I was wondering what sort of treatment would best complement my tones, if I could use the space for more warmth, and the pros and cons of live treatment vs studio treatment in binaural recording.

Half questions, half opening up a discussion I suppose.... sorry for the long opening post.

First, let me admit that I edited your original reply to reflect my change in my user name; I used to post as "Binaural Mark" but now simply post using my name, Mark A. Jay. I hope this is not a breech of the rules or of ettiquette.

Secondly, your question has several layers to it, but one thing I would suggest is that you figure out the frequency response of the mannequin head they you constructed, and then from there, "correct" it to taste. Much of your issue may lie there. This is somewhat of a tricky thing though, because just like with a regular microphone, the frequency response will vary on source-to-microphone distance, angle of incidence etc. Alternately, you could simply EQ the signal until you got the timbre that you seek. If you want to know more about how best to do that, you might want to drop a line to me (off line) as it can be a lot to post.

Anyway, commercial mannequin head mics are generally equalized for free field or diffuse field conditions (and some allow this to be switched by the user), and some other equalizations are also in use on some extremely high-end mannequin heads (most notably, the I.D. (Independent of Direction) EQ developed and used by Head Acoustics).

So, if the frequency response of the mannequin head is not to your liking, I would start there. After that, I would start paying a lot of attention to the normal stuff, like room boundary conditions / treatments, source-to-mic distance(s) and so on. Frankly, the boundary conditions are really, really important as others have discussed in other threads.

If the room is very reflective, and particularly so if rectilinear, you run a very real risk of being in a sound field that is modally very dense, and these nodes / anti-nodes will make your microphone placement (whether a mannequin head or other(s)) highly dependent upon location - and it will also make repeatable recordings that much more difficult from session to session. One thing that can work to help alleviate room affects is a near-field measurement - the closer to the instrument the more the direct sound will be in the recording. However, this is not such a great approach for instruments that are not simple mono-pole sources. That is, pretty much every instrument is a family of distributed sources (spatially), depending upon which notes are sounded and to what degree (i.e. a function of attack etc). Long story short, in the end, you will have to treat the recording space in some fashion.

Also, don't think you have to relegate binaural to live recording only. Many people have used them successfully in-studio (especially as part of a mix whereby certain parts are to be given a very enveloping soundstage, usually most noticed when the listener is wearing headphones). Others (Farina et al) have used binaural mannequin microphones to generate binaural impulse responses (at very famous venues such as La Scala, etc) that can be used as plug-ins to allow one to generate a sort of virtual mannequin head during the mix. Of course, the binaural effect you get will be that of the venue in which the binaural impulse response was acquired, but still, it can be a very creative effect.

Anyway, I hope this helps. Also, if interested, I am starting a new thread about binaural - what works, what doesn't, success stories, failures, and so on. With luck, I'll start the new thread today.