Recording the sax in stereo... sort of!

[Chris98]

Hello,

Just recently I got interested in stereo recording prompted by a little mic demo I found on the web. With stereo recording you ideally need two microphones that are identically matched. I don’t have two identical mics, in fact, I only have two mics and they are not what you’d describe as even coming close to being similar. Even the way the sound waves are turned into electrical signals operates on a completely different principle!

My set up:

But, being keen to play around and see if there’s any mileage in stereo recording the sax I decided to have a go and see how it sounded. There are several ways of setting up stereo mics and as this was my first time I decided to keep it simple and opted for the X-Y set up. I then recorded two claves being bashed together to ensure the phase was correct (making sure the wave forms moved up and down together) Also, as best I could, set the levels the same.

Rather than use my usual sax of choice, the tenor I decided to try to record my alto, I’ve hardly played it for months so it was time it got some use, and I’ve not yet managed to get what I feel is an okay recording of it.

Instead of giving you the full recording mixed with the backing track, I’ve staggered the mixing, so to start with you have just the alto (naked), then I bring in the reverb and finally I bring in the backing track.

The two mics are panned hard left and hard right, the dynamic mic is in your right ear and the studio condenser mic is in your left. I was standing about three feet away from the mics.

Chris98 – Jumpin’ Jam Alto (Build Up) 140.mp3

It’s difficult to know how much if anything the stereo recording of the sax adds compared to recording in mono like I have done thus far. And it’s probably not fair to judge the idea based on this recording as I’m using two completely different mics, but I think the stereo recording has perhaps more body to the sax sound and greater depth to the recording.

Anyway it was a bit of fun and I’d be interested to hear if anyone’s played around with stereo recording and has any advice or thoughts on what I’ve done.

Best wishes,

Chris

P.S. Pete I think I’m working this tune into the ground, do you have any more up your sleeve?

 

[kevgermany]

Liked that. Gonna have to bite the bullet and learn it one day.

Quite an imbalance between the mikes, but an interesting concept. Liked the left ear better.

 

[Chris98]

Liked that. Gonna have to bite the bullet and learn it one day.

Quite an imbalance between the mikes, but an interesting concept. Liked the left ear better.

Hi Kev,

I have the tune so well ingrained in my head from playing the tenor version that I was working hard to prevent my fingers falling to the note I'd be playing on the tenor and had to make sure I played the correct notes for the alto.

I'd love to have a go doing a stereo recording with two matched mics, but that will have to wait. It was just a bit of fun, but not really a good set up to evaluate the true potential of stereo recording. I just realised that the two mics had different polar patterns as well, I thought they were both cardioid but the dynamic mic is hyper cardioid and therefore much more directional. Listening to the recording now I think there is some mid range frequencies missing.

Thanks for listening to it,

Best wishes,

Chris

 

[Chris98]

Stereo again but a different technique...

Hello,

There is another stereo microphone technique that I’d heard about, but it sounded difficult and like you needed a hardware matrix of some kind to decode the audio, and in my mind that meant big money so I didn’t go there.

But I was wrong, this stereo micing technique sounds far more complicated than it actually is and doesn’t need any hardware if you have some basic sound recording software, and best of all it doesn’t need matched mics

It’s called the Mid-Side (MS) Stereo Microphone Technique!

So I quickly set up my mics, tweaked the levels and did a test recording of me noodling around on the tenor. If you are interested in hearing the results please click on the link (and please forgive the playing): Mid/Side Sax Test.mp3

A sort section of the noodling is repeated three times:

1st Time – (mono) just the dynamic mic pointing at the sax.
2nd Time – (stereo) the same as before except that this time the side mic has been added to create the stereo effect.
3rd Time - (stereo) the same as before with a touch of reverb added.

I’ve not put any EQ on the sax so what you are hearing is how the mic picked it up.

As well as not needing matched mics the other huge advantage of this technique is that you can choose how wide or narrow the stereo image you want during the mixing so it’s very flexible.

I’d be interested in hearing what you think of the stereo recording created by this technique, and thanks for listening.

Best wishes,

Chris

 

[Pete Thomas]

Chris, it doesn't sound to me very stereo, so hard to tell if the MS matrix is actually working.

I use MS stereo recording, and it's actually very important to either use a hardware/software dedicated MS matrix, or else do a DITY matrix, which means you take two parallel outputs from the figure 8 mic, and send to two channels, but put one of them out of phase.

 

[Chris98]

Chris, it doesn't sound to me very stereo, so hard to tell if the MS matrix is actually working.

I use MS stereo recording, and it's actually very important to either use a hardware/software dedicated MS matrix, or else do a DITY matrix, which means you take two parallel outputs from the figure 8 mic, and send to two channels, but put one of them out of phase.

Hi Pete,

Thanks for having a listen. I'm still finding my way a bit with this technique and perhaps the sax isn't the best instrument to try it on, to be fair I was playing straight on to the mic.

I'm doing a DIY matrix in Logic, duplicating the figure of 8 side audio and then phase inverting it, the original is panned hard left and the phase inverted one is panned hard right and I've joined the faders together.

Can I ask, how you do your MS processing?

I'm going to have another play and see how it goes but I might be better off spending my time learning to play the sax rather than mucking around with microphones .

All the best,

Chris

 

[Pete Thomas]

In logic it's easy.

You just insert a direction mixer plugin and choose "MS". No messing around with phase inversion (which won't work anyway unless your fig 8 mic has 2 physical inputs)

 

[Chris98]

Hi Pete,

I couldn't get Logic to invert the phase so I used a free meter plug-in ( Sonalksis ) that has a phase invert switch


I've not tried the 'direction mixer plugin' I'll have a hunt for it.

I don't understand what you mean by:

No messing around with phase inversion (which won't work anyway unless your fig 8 mic has 2 physical inputs)

My fig 8 mic has only one O/P.

I've just done another recording which went horribly, horribly wrong, I think I need to learn to play the sax before I do any more recording! Oh well.

The reason for pursuing stereo recording is that I feel when I use a single mic I loose something of the character of the sax that I can hear when I'm playing it. I am hoping that the wider pick up and stereo imaging might retain some of that character.

Thanks for your help,

Chris

 

[Pete Thomas]

That's right, a mic has one output. But what a MS matrix does it it splits that one signal into two, and inverts the phase of one side, so it is sort of out of phase with itself.

An MS matrix will do this (either in hardware or software)

What I was trying to explain above, is that what i used to do was to take two parallel output from the one fig 8 (side) mic. I did this by splitting each wire of the cable into 2 so there are basically two XLR plugs for one mic. Then each plug goes into a separate channel, and one has the phase inverted.

 

[Chris98]

What I was trying to explain above, is that what i used to do was to take two parallel output from the on fig 8 (side) mic. I did this by splitting each wire of the cable into 2 so there are basically two XLR plugs for one mic. Then each plug goes into a separate channel, and one has the phase inverted.

That makes sense, just swap the hot and cold wires round on the second XLR and you've got your phase inverted, then go straight into the desk.

 

[Pete Thomas]

That's right.

What I did was connect the XLR on the end of the lead, then take another cable off of the back, and connect 2 and 3 the other way round.

But I then got a great little preamp/mixer from Mike Skeet.


And I then used that as the preamps were better than my desk, and it was very easy to use. But now that there is such an easy matrix for MS in Logic I don't need it, so probably going on ebay soon.

 

[Chris98]

Mike Skeet sounds like an interesting person, I see he's into Binaural recording as well. I can remember when I was a kid my dad put a pair of headphones over my ears and told me to close my eyes. He then played a Stax dummy head recording and heard this person walk across the room and whisper in my ear, I had goosebumps it was so realistic, I'm sure I felt her breath!

Shame about your nice bit of hardware now being made redundant, but I guess that's the way things go.

All the best,

Chris

 

[Pete Thomas]

One thing I would add.

There's only any real point in recording the saxophone in stereo if either:

The mic is very close - so you actually get a wide enough image. Too far away and the sound comes from a very narrow source anyway so might as well be mono

or

There is lots of natural room ambience, as this will be the main stereo content of the signal, not the saxophone itself (as above)

This only makes sense if the room ambience is nice and you don't ever want to lose it (e.g. to replace with another reverb).

Having said that, your recording (and playing) sounds nice miked like that, which is the important thing IMO.


Talking of binaural recording, another bit of kit I may have to let go of is my "AKG "Harry The Head" stereo pair of microphones in a head:

 

[Chris98]

One thing I would add.

There's only any real point in recording the saxophone in stereo if either:

The mic is very close - so you actually get a wide enough image. Too far away and the sound comes from a very narrow source anyway so might as well be mono

or

There is lots of natural room ambience, as this will be the main stereo content of the signal, not the saxophone itself (as above)

This only makes sense if the room ambience is nice and you don't ever want to lose it (e.g. to replace with another reverb).

Hi Pete,

Thanks for your comments on two different reasons for using a stereo mic set up, I think I got too caught up in playing around to seeing if it worked to think through if it was appropriate, and if so what it was I want to achieve. You've given me a few things to consider.

The acoustics in the room I play and record in are fairly dead, so trying to picking up the natural room ambiance with the stereo set up isn't really worth it and having a dryer recording means more possibles with reverb in the mixing (I still finding my way around Space Designer!).

The dynamic mic I used for the mid mic has a super cardioid pickup pattern, which if memory serves me right sits in between cardioid and hyper cardioid, therefore being quite directional. I was standing between 3 and 4 feet away from the mic set up, but I will have a go next time playing a little closer to see if that accentuates any stereo spread. I'm thinking if anything the low notes will picked up more in the left hand channel and the higher notes in the right.

Talking of binaural recording, another bit of kit I may have to let go of is my "AKG "Harry The Head" stereo pair of microphones in a head:

I like the look of 'Harry The Head' and you've got to hold onto him even if purely for nostalgia. Have you done much recording with him? I'm guessing binaural recording requires a different recording philosophy where you don't layer tracks but capture a performance in on go with just the head?

Best wishes,

Chris

 

[Sweet Dreamer]

Nice clean recording. Great sax playing too.

 

[Saxlicker]

Having said that, your recording (and playing) sounds nice miked like that,

I thought so to.
Welldone

 

[Chris98]

Hello Sweet Dreamer and Saxlicker,

Thank you for your kind comments on my playing and recording.

I carried on playing around with stereo recording of the sax and moved the microphones in closer as Pete suggested. It was an interesting experiment and seemed to capture more of the sax sound that I thought I was hearing, but it proved quite hard to combine this with the backing track in the mix. I’m guessing it’s because the two acoustic spaces didn’t match.

I’m coming to the conclusion that my ears can grow accustomed to how things sound and I loose the ability to discriminate between good and bad, and keep clearly in my mind what I’m trying to capture. For example, the first sound bite was recorded in stereo, it sounded okay at the time but a few days later I listened again and hated the recording, so much so I had to re-record. This time I put up just single microphone reasonably close! You live and learn and without playing around I’d never learn anything!

Sax Recording: Stereo
Sax Recording: Mono

I think it might pursue the stereo recording if I was recording just the sax and say an acoustic guitar but when trying to mix my playing in with a backing track I’ll stick to just a single microphone.

Best wishes,

Chris