hi - quoting something i read - Since it's a figure-8 pattern, the two sides are 180 degrees out of phase - would this be true of ribbom mics ?
i get that a condenser has back to back out of phase diaphragms
i get that a condenser has back to back out of phase diaphragms
thanks ive been looking at an RB 100 from thomman - not sure if the lobes are identical - i cant find the info on thomman
TheRB-100 lobes are not identical, but fairly closely matched:
https://images.thomann.de/pics/prod/107913_datasheet.pdf
https://images.thomann.de/pics/prod/107913_datasheet.pdf
Valve mic are not related to capsule directivity, as a valve mic can be condenser ( hence with possibility of a multi pattern capsule), or a ribbon ( some Royer use a valve headamp) or even a condenser ( if we search enough i'm sure we would find some...).
Let suppose it's a condenser mic you ard talking about, then yes they'll be close enough ( for rock and roll!).
There is difference between directivity given by different capsules technology and i tend to think the native directivity given by a technological choice is often the 'best' you can find ( omni with pure pressure capsule or fig of 8 with pressure gradient - ribbon) but in practice anything will work and give a kind of usefull rendering.
What are you trying to record ( source and style)?
I often use multi pattern condenser ldc mics for M/S, A/B or XY. They works. Sometime small condenser capsule sound better or ribbon... depend on source and what you wish as outcome.
What do you mean by 'back lobe cannot be heard'? If you refer to fig of 8 it's not true, it's integrated to what you hear. Blumlein couple give an real life example: what is behind the couple axis is heard but upside down! (Left on right nd right on left).
Let suppose it's a condenser mic you ard talking about, then yes they'll be close enough ( for rock and roll!).
There is difference between directivity given by different capsules technology and i tend to think the native directivity given by a technological choice is often the 'best' you can find ( omni with pure pressure capsule or fig of 8 with pressure gradient - ribbon) but in practice anything will work and give a kind of usefull rendering.
What are you trying to record ( source and style)?
I often use multi pattern condenser ldc mics for M/S, A/B or XY. They works. Sometime small condenser capsule sound better or ribbon... depend on source and what you wish as outcome.
What do you mean by 'back lobe cannot be heard'? If you refer to fig of 8 it's not true, it's integrated to what you hear. Blumlein couple give an real life example: what is behind the couple axis is heard but upside down! (Left on right nd right on left).
thanks - i already started another thread about my confusion - on a condenser fig 8 i have to reverse the phase on left channel - ive been told that the back lobe of a ribbon records out of phase info - is this wrong?
I think you are mixing what happen with the capsule's directivity pattern and M/S matricing which will lead to confusion....
About directivity pattern:
https://www.lewitt-audio.com/blog/polar-patterns
Bidirectional indeed record backside info out of phase with front side info but it record both at the same time. Issue happen when you use couple as there is some destructive interference happening ( which lead to 90° SRA ( Sound recording angle) for Blumlein couple in front AND back side as can be seen on the schematics in the next article...).
https://en.m.wikipedia.org/wiki/Blumlein_pair
About matricing:
https://www.soundonsound.com/techniques/introduction-mid-sides-recording
For MS we need M+S and M-S to dematrice to L/R so we need the side (S) signal in and out of phase on 2 of the three chanels needed on the console ( the third being the Mid/Mono/M). Hence the confusion imho... 😉
About directivity pattern:
https://www.lewitt-audio.com/blog/polar-patterns
Bidirectional indeed record backside info out of phase with front side info but it record both at the same time. Issue happen when you use couple as there is some destructive interference happening ( which lead to 90° SRA ( Sound recording angle) for Blumlein couple in front AND back side as can be seen on the schematics in the next article...).
https://en.m.wikipedia.org/wiki/Blumlein_pair
About matricing:
https://www.soundonsound.com/techniques/introduction-mid-sides-recording
For MS we need M+S and M-S to dematrice to L/R so we need the side (S) signal in and out of phase on 2 of the three chanels needed on the console ( the third being the Mid/Mono/M). Hence the confusion imho... 😉
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