ORTF with Shure A27M Vertical Alignment

[violinbf]

I just started recording with 2 SDCs and a Shure A27m stereo mount and had some questions about it's design. It is possible in XY to have the Capsules mounted vertically aligned. However the only way I can get the mics in position for ORTF is for the mic's to be vertically seperated by about 65mm. There is a photo in the A27m user's guide of this setup with two SM81s.

http://www.shure.com/ProAudio/Produc...us_pro_a27m_ug


I am wondering if this setup is not optimal because the capsules are not on the same vertical plane. Does anyone have any experience? My shockmounts make it impossible to get the capsules any closer together unless I was to use a more traditional stereo "t-bar" like the Sabra Som st-4.

Is there any negative impact to this setup? Should I buy another t-bar?

[Corran]

I once did an ORTF arrangement like that, with a large vertical displacement. Came out okay, I didn't notice any obvious phase issues or whatever. But it was only once and not a critical recording so I didn't listen as critically as I might have otherwise.

I will say that the PDF does have a nice quick-reference for various stereo micing techniques. Even has NOS which I hardly see specifics on. Though the X-Y seems funky (135 degrees??).

The Sabra-Som ST-4 has been a very good system though, so I would definitely recommend it.

[boojum]

I have the Sabra and the Shure bars. The Shure is the more rugged. I can also place two mics quite close to each other. There are three options for vertical spacing and the closest works fine for me with SDC's.

I do no think that XY has to be 90 degrees. It can be varied.

[edwinhurwitz]

I've enjoyed the A27M, but it's hard to get aligned easily for some arrangements, since both barrels spin when it's loose. I just got a Grace Spacebar, which I think will be easier.

Edwin

[boojum]

I use the A54's (?) the donut mic holders with the A27 so I can move them in an arc pretty easily without fiddling with the bars. I also use the Williams "origami" solution to angles and distances. Check it out. ;o)

[BLP]

Originally Posted by violinbf

I just started recording with 2 SDCs and a Shure A27m stereo mount and had some questions about it's design. It is possible in XY to have the Capsules mounted vertically aligned. However the only way I can get the mics in position for ORTF is for the mic's to be vertically seperated by about 85mm. There is a photo in the A27m user's guide of this setup with two SM81s.

I might be confused, but it seems that, if you flip the black cylinder section you should be able to obtain a minimal 31mm vertical spacing using the A27. I'm not sure exactly which mics you're using, but that closest stud setting should work with most SDCs...

[violinbf]

Thanks to all for the replies.

I am using the MXL 603 stereo set which comes with some large and unwieldy shock mounts. I inherited the a27m and am trying to decide if I should cough up the extra 40 bucks for another T mount.

Take a look...I think this is as good as i can get with this setup.

does anyone see any problems with this? I am recording classical violin and chamber music.

[Corran]

Well don't discount the fact that, if you get the ST-4 you can do AB stereo as well if you get the omni caps for the 603. I love the 603 with omnis for cheap classical recording purposes.

[hughesmr]

Originally Posted by BLP

I might be confused, but it seems that, if you flip the black cylinder section you should be able to obtain a minimal 31mm vertical spacing using the A27. I'm not sure exactly which mics you're using, but that closest stud setting should work with most SDCs...

You are right. I had a pr of KM184s and an A27 several years back and this was my ORTF solution. I was using the usual Neumann clamps, no shockmounts.

[violinbf]

Yeah I am pretty impressed with the quality for so little $$.
I paid $120 for a brand new set including shipping the bar and cables...it works. I am using the E-MU tracker pre (paid about $100 new) and it makes for a very convenient mobile 100% bus powered solution.

I will probably spring for the ST-4 and the omni's too when I get bored with this sound.


I can't flip the spacer because my shock mounts won't allow it. I could ditch the mounts and use clips to get the capsules closer but it is nice to have the isolation. I am not sure which is the lesser of evils.

[Corran]

Personally I hardly bother with shockmounts, in a classical recital. Just doesn't seem to make a difference.

I bought a pair of omni caps for $40 on ebay. They really haven't come off. I never liked the sound of the cardioid caps on the 603 myself, at least not for main-pair work. I think I also got my ST-4 off of ebay for a little cheaper than you can find it at online retailers. I also bought several lengths of aluminum bars to retrofit the ST-4 with a wider length bar - use it on almost every gig.

Edit: corrected the price my omni caps were. I don't know what I was thinking at the time I wrote that.

[jnorman]

agree with corran - forget the shockmounts, use regular mic clips, flip the black cylinder to obtain the closer vertical spacing. a small amount of vertical displacement will have no effect for normal use of ORTF. even the most expensive and sophisticated ORTF mounts by DPA, schoeps, AEA and Grace all rely on a small amount of vertical displacement.