Your 'GOTO' stereophonic mic. technique

James Kuhn · April 13th, 2012, 11:29 AM

Greg, Seth, Ty, & Gary...alright, that's enough! You guys are having way too much fun! Heh, heh!

Regards,

J.

Gary Nattrass · April 13th, 2012, 03:55 PM

I love the smell of tape oxide in the morning, to me it smells like victory!

anyway whatever happened to Q sound I though that was the saviour of stereo and surround mixing?

Greg Miller · April 14th, 2012, 05:15 AM

I was attending Penn State in the late '60s. There was some collaboration between the music department and the broadcasting people, which resulted in some very pleasing 4-channel R-R recordings. When done with four discrete tape channels, the sound was quite impressive. There were even a few "experimental" broadcasts, using the campus FM station for two channels, and a local FM station for the other two. (Both transmitters were in the same building, so by parking the R-R deck in the hallway, and running long audio cables to the two respective patch bays, it was possible to achieve this without any intervening telco lines which would have created phase problems.)

Quad never caught on in the consumer market, in part because there were at least three different systems: Sony/Columbia SQ matrix system (which did not work well), the RCA system using a high frequency subcarrier on the LP (which also did not work very well), and the Dynaco system using a simple additive/subtractive matrix (which also had poor separation, plus an unusual speaker placement: FrontLeft, FrontCenter, FrontRight, and RearCenter. The consumers, faced with three incompatible systems, none of which worked very well, wisely decided to steer clear of the whole mess. Quad was, back then, technologically impractical, and well before its time.

Christian Brown · April 15th, 2012, 01:22 PM

Quote:

Originally Posted by Paul R Johnson

To the audio recordist the concept of recording stereo from a distance with a shotgun type mic just doesn't cut it because the polar response is narrow at the top and cardioid at the bottom causing huge amounts of image shift as the music content changes frequency.

Yes, thank you for responding with what I was thinking! I frequently record music "at a distance" with omnis. Shotgun microphones are rare at recording sessions.

[Addendum: I was confirming Paul's assertion that music recordists may think differently about recording than a dialogue/FX recordist. Many mics have different patterns at different frequencies (even omnis), and rarely do you hear image shift because of it. However, shotguns don't sound as full as omnis at a distance and the off-axis coloration leads to a smearing of the sound. To learn more, visit: http://www.soundonsound.com/sos/aug1...nda-0811-1.htm.]

Quote:

Originally Posted by Paul R Johnson

I'm not certain the test was matched very well to the venue. From what I heard, I expected a much larger venue and instrument, but was surprised to find out it's real size. The recording seemed to have been planned to sound bigger than reality, and I feel this was a mistake.

Smaller spaces are often more reverberant than larger spaces because the reflections are early and dense. Small chapels with hard surfaces are sometimes sought for choral recordings for this reason. Bigger doesn't necessarily equal more reverb.

With regards to the "match" of test to venue -- I encourage you to try the same test in any venue. XY will sound smaller than reality. A vectorscope is not needed to confirm good sound. You don't even need to listen to the organ play in this case. It is clear the instant you hear the room tone.

Paul R Johnson · April 15th, 2012, 02:33 PM

I suppose it depends on your version of reality. I've done a few live radio events in a really BIG church and needed it to actually sound smaller to retain definition - but I still don't really find X/Y to be unrealistic. When I do M/S I usually mix it so it sounds as similar to how I'd have made X/Y sound. I Like A/B for some things but have trouble with the hole in the middle. I have major difficulty hearing the difference between X/Y and ORTF which a colleague simple dribbles over. For me, X/Y works for loudspeakers and is solid in headphones too. It's all to do with personal preferences really.

As for the vector scope, I tend to always have one on the go for mixing projects because it's often a good confirmation that something isn't quite right. You get used to typical displays, but it's when something just doesn't sit in the mix and you notice something with a big phase error, or loss of stereo image.I recorded a grand piano only a few weeks ago with an old fashioned more distant stereo mic and two close mics, recorded direct into cubase using 4 channels. Working with the two close mics it was only the vectorscope that made me suddenly realise I'd messed up the routing and had recorded just one mic to two channels. Something didn't sound quite right - and the vectorscope made it pretty obvious what had happened. The distant mic was no good for the close perspective I needed, so in the end, I panned the two identical tracks left and right and applied a reduction slope to both, with one reversed, so the lower notes were louder left and the higher notes right. Not stereo, but it actually worked!

Colin McDonald · April 17th, 2012, 04:39 PM

Quote:

Originally Posted by James Kuhn

... Images of your favorite set-up is a plus.

James, here's a few quick iPhone pictures of the inexpensive rigs I use. If I could afford it I would much rather use something like these
Spacebar Stereo Microphone Positioners
Stereo Bar Assembly » Rycote
but instead I spent about £15 at Maplin for a basic stereo bar and two goosenecks.
With these I can do a pretty quick ORTF setup using a card template and a slightly less quick X-Y rig. A bit fiddly, but certainly more affordable if like me you only record a few orchestras, choirs or ensembles every year.

I have to say the SM6 shockmount that comes with the Rode NT2A studio pack has a great unadvertised feature - the pop shield mounting has a standard 5/8" male thread on it so you can easily suspend another mic over it with a suitable spacer or gooseneck. It only takes a me couple of minutes now to set up for M-S.

I have found this thread very interesting - thanks for starting it James!

Pics of ORTF (top row) and X-Y rigs (middle left) using a pair of Rode NT1As and M-S rig (middle right and bottom row) using a Rode NT2A for the side mic. The Maplin stereo bar and goosenecks are also shown.

James Kuhn · April 17th, 2012, 05:40 PM

Colin...thanks for the images! I enjoy seeing the inventive way people arrive at their mounting solutions. I have found an interesting 'Blumlein Array' mounting solution using my SHURE A27 and Grace SB-66. It holds my AKG c414 XLS pair and it gives me confidence the mics. are safe.

Up until my purchase of the Grace Bar, I've been using a SHURE A27, a surprisingly versatile design. Very nice piece of kit.

If I can figure out how, I'll attach a few images of my 'rig'.

Thank you for sharing.

J.

April 13th, 2012, 11:29 AM	#46
James Kuhn Major Player Join Date: Sep 2011 Location: Merritt Island, Florida Posts: 865	Re: Your 'GOTO' stereophonic mic. technique Greg, Seth, Ty, & Gary...alright, that's enough! You guys are having way too much fun! Heh, heh! Regards, J.

April 13th, 2012, 03:55 PM	#47
Gary Nattrass Trustee Join Date: Apr 2008 Location: Cornsay Durham UK Posts: 1,992	Re: Your 'GOTO' stereophonic mic. technique I love the smell of tape oxide in the morning, to me it smells like victory! anyway whatever happened to Q sound I though that was the saviour of stereo and surround mixing? __________________ Over 15 minutes in Broadcast Film and TV production: http://www.imdb.com/name/nm1044352/

April 14th, 2012, 05:15 AM	#48
Greg Miller Trustee Join Date: Jan 2011 Location: Pennsylvania Posts: 1,786	Re: Your 'GOTO' stereophonic mic. technique I was attending Penn State in the late '60s. There was some collaboration between the music department and the broadcasting people, which resulted in some very pleasing 4-channel R-R recordings. When done with four discrete tape channels, the sound was quite impressive. There were even a few "experimental" broadcasts, using the campus FM station for two channels, and a local FM station for the other two. (Both transmitters were in the same building, so by parking the R-R deck in the hallway, and running long audio cables to the two respective patch bays, it was possible to achieve this without any intervening telco lines which would have created phase problems.) Quad never caught on in the consumer market, in part because there were at least three different systems: Sony/Columbia SQ matrix system (which did not work well), the RCA system using a high frequency subcarrier on the LP (which also did not work very well), and the Dynaco system using a simple additive/subtractive matrix (which also had poor separation, plus an unusual speaker placement: FrontLeft, FrontCenter, FrontRight, and RearCenter. The consumers, faced with three incompatible systems, none of which worked very well, wisely decided to steer clear of the whole mess. Quad was, back then, technologically impractical, and well before its time.

April 15th, 2012, 02:33 PM	#50
Paul R Johnson Inner Circle Join Date: Nov 2005 Location: Lowestoft - UK Posts: 4,016	Re: Your 'GOTO' stereophonic mic. technique I suppose it depends on your version of reality. I've done a few live radio events in a really BIG church and needed it to actually sound smaller to retain definition - but I still don't really find X/Y to be unrealistic. When I do M/S I usually mix it so it sounds as similar to how I'd have made X/Y sound. I Like A/B for some things but have trouble with the hole in the middle. I have major difficulty hearing the difference between X/Y and ORTF which a colleague simple dribbles over. For me, X/Y works for loudspeakers and is solid in headphones too. It's all to do with personal preferences really. As for the vector scope, I tend to always have one on the go for mixing projects because it's often a good confirmation that something isn't quite right. You get used to typical displays, but it's when something just doesn't sit in the mix and you notice something with a big phase error, or loss of stereo image.I recorded a grand piano only a few weeks ago with an old fashioned more distant stereo mic and two close mics, recorded direct into cubase using 4 channels. Working with the two close mics it was only the vectorscope that made me suddenly realise I'd messed up the routing and had recorded just one mic to two channels. Something didn't sound quite right - and the vectorscope made it pretty obvious what had happened. The distant mic was no good for the close perspective I needed, so in the end, I panned the two identical tracks left and right and applied a reduction slope to both, with one reversed, so the lower notes were louder left and the higher notes right. Not stereo, but it actually worked!

April 17th, 2012, 05:40 PM	#52
James Kuhn Major Player Join Date: Sep 2011 Location: Merritt Island, Florida Posts: 865	Re: Your 'GOTO' stereophonic mic. technique Colin...thanks for the images! I enjoy seeing the inventive way people arrive at their mounting solutions. I have found an interesting 'Blumlein Array' mounting solution using my SHURE A27 and Grace SB-66. It holds my AKG c414 XLS pair and it gives me confidence the mics. are safe. Up until my purchase of the Grace Bar, I've been using a SHURE A27, a surprisingly versatile design. Very nice piece of kit. If I can figure out how, I'll attach a few images of my 'rig'. Thank you for sharing. J.