[Tom Powers]

Hello,

So I’ve begun an experiment and wanted to poll the collective to get your thoughts.

The scenario is twofold:

In the first case, if you had a guitar track panned to the left and blended and a binaural track of the guitar taken from the listening position where the amp was on the left, and you phase aligned the signals, could you blend that in for a greater panning experience?  Realizing that binaural effects in a stereo field lose effectiveness, the original panning track would take care of that, but when the listener went to headphones, the binaural “presence” would come to life.

Thoughts?

Scenario 2 (Given that scenario 1 actually works)

If you didn’t have that binaural track of the guitar…could you make one by recording a playback of the guitar track in the room with it panned heavily to the left (and maybe even EQ’d and doubled/delayed for precedence effect) and then blend this new binaural track back in…similar to reamping?

All insight is appreciated

Thanks

TP

[Bob Katz]

How was the binaural track made? “Blending” in binaural with a multi-miked stereo mix is an art that I would like to learn myself. It’s not just “blending”… there’s a lot of necessary manipulation to make it sound convincing. I have a wonderful binaural recording I made with a dummy head in a jazz club… .but of course the balance is a bit awry… the piano is too far away and the vocal is pretty much lost. I have the full set of close mikes available to me, provided by the club owner, but have not yet had the time to investigate the tools needed to”mix in” the close mikes with specialized manipulation to end up with a convincing binaural picture. Not simple. Not simple at all.

I know that Flux SPAT can output a mix into various formats, including binaural. I also own “Virtuoso”, which can take a stereo or immersive mix originally intended for loudspeaker reproduction, and produce a convincing picture of loudspeakers or perhaps even performers in space — to be played in binaural on headphones!  That tool works very well for its intended purpose….  PERHAPS it would allow me to take the close stereo piano mikes and move them to virtual positions  to integrate with the soundstage that the main binaural microphone picked up.

[Tom Powers]

I think that’s really the crux of the issue is how the BA (binaural) track was made.

 

In my first thought, during the individual instrument tracking, if we had the cabinet mics on a guitar and had the BA head in a listening position where the guitar was on the left… then the signals are more straightforward and related.

Now if I didn’t have that…would it be possible to MAKE a BA signal by playing back the guitar track, panned to the left, and use the BA mics to record the playback from a listening position where the guitar sound is on the left…sort of like reamping a track.

My goal , as crazy as it sounds, is to try to bury BA signals in the stereo mix (say for guitars, and vocals, and maybe drum overheads) that when played on headphones “comes alive” but otherwise, like most BA in stereo …the effect isn’t really noticeable.

I’ve done some preliminary trial and error and had surprisingly good results, but I’m NOT doing this with a room mic BA capture, like the Jazz club Bob mentions, but instead individual BA parts of specific instruments.

There’s a fine line between innovation and a total mess and I’m hoping I don’t look behind me and see that line 🙂

What pitfalls should I be looking for here other than phasing issues which are obvious

All insight is appreciated

TP

 

[Bob Katz]

If you re-amp to get the binaural image, then you are of course introducing the coloration of that speaker. But since guitar amp coloration is the goal, reamping could be a valid solution.

As for me, I’d like to try some binaural transformation plugins. Virtuoso can simulate loudspeaker locations in space from stereo  (or immersive) mixes, including those made from panning close mikes to positions. Maybe it can do a good job with the integration of a binaural mike with spots. Feed the spots into virtuoso and mix that with the existing binaural mike. It’ll probably be a mess at first, delays and all have to be aligned as well. Have to put your ears on and work until it sounds convincing!!!!!

[Tom Powers]

Using the binaural “reamping” technique described above, I’ve been getting some very interesting results (as long as the signals are phase aligned with the original track).

The binaural tracks are very bright, and in recent research, I’ve found this graph from head-acoustics and DPA.  It looks like an “inverse” htrf filter used for binaural playback.

While I can see how this would take care of the extraordinary brightness in playback, will it detract from the binaural effect on headphone playback? I’ve only found this today and am away from the studio.

[Bob Katz]

Tom, you’re on the bleeding edge of practice and way ahead of me. Can’t help you there. But I want to say that Andrew Mayo and a colleague are giving a major talk on how to mix in Binaural. Here’s his notification. I’ll also add it to the news and events forum here. Could be well worth attending (for both of us!)

 

What is binaural audio and what can it be used for?
It is one of the most popular forms of immersive audio, consisting of an apparently traditional stereo mix (because it has two channels, L and R) but the content has been spatialised in 360 degrees via phase manipulation software. It works very well in headphones because each ear receives different information and therefore our brain can build a perfectly believable 3D sound image, much in the same way that 3D lenses work in the movie theatre.
The big advantage of binaural audio is that it can be easily transported without losing its properties. It can be uploaded to any streaming platform (Spotify will take it, for example) and it can be transferred via WhatsApp or any other social network because the file can handle data compression very well up to a reasonable 320 Kbps AAC or MP3 without losing the spatial feeling.
On Saturday, May 27th, from noon through 4 pm, Martin Muscatello and I will give a hands-on seminar on binaural mixing, showing lots of real examples and explaining in detail how we produced them. We will start a mixing session from scratch so you can see the entire process. The seminar will be in English and 100% online, so you can attend from anywhere.
To get more information and costs, please write an email to Julia (our studio coordinator): [email protected]
Thanks!!!

[Tom Powers]

Well Bob, here’s what I’ve found.

If you apply that EQ graph above to a binaural recording, you can play it through loudspeakers and it sounds like a regular track, but as I feared, you lose the binaural effect when on headphones.

What I’ve found so far is that if you have a stereo mix and you’ve delayed, EQ’d, and panned  duplicate tracks with precedence effect in mind, then when you add the binaural “reamp” track that I explained above, that the stereo mix gets real bright and brittle. When you listen on headphones, it sounds great.

So I experimented….dealing with 2 guitar parts, one on the left and one on the right (and the binaural re-amped tracks of them)

First I took the regular stereo mix guitar tracks out and left the binaural tracks in the mix. Result:  The headphones sounded great, but the stereo mix was thin and brittle

I verified that if I put the EQ setting on the Binaural re-amp tracks, that the headphone effect pretty much dies off but the stereo mix was fine.

So then I tried to balance the binaural tracks (without the EQ setting) with the stereo tracks and blend them, and that sort of worked? The Binaural effect wasn’t as prominent, but it was there….just not to the effect I wanted, and the stereo loudspeaker listening was good because the brightness was removed.

So … the last, and most promising result, was based on this premise:

The binaural reamped tracks , when blended with the stereo tracks were all being sent to the same guitar bus ( one for each guitar). As previously stated, the stereo track was too bright but the headphones sounded great.

I then decided that if I left the binaural tracks alone, and used the above EQ settings on the Stereo tracks…the end result is a good sounding stereo mix on the speakers (because the mid-high frequencies were cut on 2 of the 4 guitar tracks going to the guitar bus)…but to my surprise, the binaural effect was still very prominent in the headphones and “leftover” frequencies after the EQ settings on the stereo tracks, really didn’t bother the headphone mix.

More to come as I and to try a few other things…like what does it sound like if I record the Binaural “reamped” tracks lower than ear level, and then blend that it…will it sound like the guitar is physically higher ?  What would it sound like if I made one reamp track below the speakers and one above and blend them into the stereo tracks…will I get a “wall of sound?”

Of course, much of this experimentation results in trash, but some of this is actually working out…so more to come.

I’ll definitely check out the process by Andrew Mayo…thanks!