Topic: Running an A/B mic comparison

[alpine85]

I'm thinking about doing a little A/B comp tomorrow night at the Kimock show.  (stock 460s vs JW 460s, both with CK1 caps)

It seems like the standard practice is running the 2 sets vertically, with one pair 6 inches or so on top of the other pair. 

For me, it would be a helluva lot easier to run them horizontally, separated by a foot or 2  on the  manfrotto triple mic bar, rather than having to join 2 superclamps and clamp the 2nd pair underneath.

Sound-wise, would there be any advantage to one method over the other? 

It seems to me there would be more of a blockage effect running vertically (one would be partially screened from above, while the other would be partially screened from below, while the effect would be less significant the other way (having one partially blocked to the L, the other partially blocked to the R).

Thoughts?

[F.O.Bean]

I know everyones ears are different, but I absolutely HATE A/B configs It has zero stereo effect and no sound staging, at least IMO Try DINa/DIN instead

[Gutbucket]

Question is about doing an 'A to B' comparison between pair A and pair B, not about the 'A-B' spaced mic configuration.

I like one of two approches, both of which eliminate spacing variables- simply run one pair at a time and swap mics at set-break without changing mic position/angles -or- gaff tape the mics together one over the other in the same mounts so that the left mics are as coincident as possible and so are the right mics.  [shrug]

[SmokinJoe]

As long as you are picking up pretty much the same thing, being left/right a little is fine.  If you were stage lip with guitars on right, drums on left, then the mics wouldn't be picking up the same thing, one would have more guitar, the other more drums, which makes it hard to compare them.  If you are 30' from stage doing a PA recording being side by side should result in the mics seeing the same basic information.

[alpine85]

Question is about doing an 'A to B' comparison between pair A and pair B, not about the 'A-B' spaced mic configuration.

Correct.  Guess I should have been more clear and said "A vs. B" or "mic shootout" or something. 

I like one of two approches, both of which eliminate spacing variables- simply run one pair at a time and swap mics at set-break without changing mic position/angles -or- gaff tape the mics together one over the other in the same mounts so that the left mics are as coincident as possible and so are the right mics.  [shrug]

Thanks Gut... good ideas.  The only downside to the set-break one is that a direct comparison of the same passage of music wouldn't be possible.  I like to take a 15-30 second clip and listen to one right after the other, or cut and paste the 2 sources, switching every 15 seconds or so between the 2.  I remember reading somewhere (probably here on TS) that our brain can only retain "audio memory" for like 3 seconds or something.

Taping the mics is an interesting approach, and would definitely eliminate the spacing issues.  I wonder, though...  wouldn't blocking the vents in the caps affect the sound? 

[alpine85]

As long as you are picking up pretty much the same thing, being left/right a little is fine.  If you were stage lip with guitars on right, drums on left, then the mics wouldn't be picking up the same thing, one would have more guitar, the other more drums, which makes it hard to compare them.  If you are 30' from stage doing a PA recording being side by side should result in the mics seeing the same basic information.

I ended up being only about 16 ft. from the stage, so I put the 2 pairs one in front of the other (by about 16 inches or so).   I was thinking along the same lines as you - that going left/right I would pick up different stuff from the stage (plus there was a bar to the left, so that side may have picked up more chatter).   I also figured (maybe incorrectly) that at that distance I'd be better off going front-to-back as opposed to vertically.   As it turned out,  one pair may have picked up slightly more stage and the other slightly more PA, but I think the inherent sound of the mics still comes through OK.

[alpine85]

Here's the comp:

http://taperssection.com/index.php?topic=156089.0

[Gutbucket]

Thanks Gut... good ideas.  The only downside to the set-break one is that a direct comparison of the same passage of music wouldn't be possible.  I like to take a 15-30 second clip and listen to one right after the other, or cut and paste the 2 sources, switching every 15 seconds or so between the 2.  I remember reading somewhere (probably here on TS) that our brain can only retain "audio memory" for like 3 seconds or something.

Yeah, the drawback of that approch I think is more due to differences in the band's playing (2nd set is usually better, isn't it?) possible PA adjustments and other differences between sets like more or less people in the room.  The audio memory thing is a different issue, some would argue that some critical listening choices are better made with longer term listening anyway rather than quick A-B switching.. argument being that quick switching highlights certain differences, but those differences may not be particularly relavant to real-world normal listening preferences, and those differences may be better sensed by listening to longer samples.  I think there is merit in both quick A-B swiching and longer sample listening approaches.

Taping the mics is an interesting approach, and would definitely eliminate the spacing issues.  I wonder, though...  wouldn't blocking the vents in the caps affect the sound? 

Shouldn't block the vents significantly for normal tubular-bodied capsules.  That's how many M/S setups are arranged.  I would orient the mics so that one is directly above the other so they are symetrical for sounds arriving in the horizontal plane and one doesn't shadow the other.