The No.1 Website for Pro Audio
Plexiglas around microphones? Please explain!
Old 16th January 2020
  #1
Lives for gear
 
DirkP's Avatar
Plexiglas around microphones? Please explain!

This weekend I watched a concert from 2008 at the german channel Alpha - most of the times fantastic audio in surround.
I was confused by those glasses around the mics of the horn-section. What purpose do they serve? Is this common?

I have a screenshot attached. Here is the entire video:



As the amateur I am, I thought it is about as worse as it gets if you put a source in front of a microphone while the source is directed towards glass or similar materials directly or not to far behind the mic?
Attached Thumbnails
Plexiglas around microphones? Please explain!-screenshot-2020-01-16-16.32.23.jpg  
Old 16th January 2020
  #2
that's a cheap way to have acoustic-foldback so that the player can hear her/himself
Old 16th January 2020
  #3
Lives for gear
 
hbphotoav's Avatar
 

That type "shield" is generally used to redirect (reflect) sound back and away from "frontline" mics (usually vocals). I usually see them in front of crash and ride cymbals in drum kits. They don't absorb any energy... they just redirect it toward the backline, which, as Avillata mentioned, may provide some acoustic benefit to the player. As small as the one in the photo is, I'd doubt it was having much effect.
Old 17th January 2020
  #4
Lives for gear
Often hyper directional mics have a small but significant rear pickup lobe....could this disc be aimed at reducing sensitivity to sounds coming directly from the rear of the mic ?
Old 17th January 2020
  #5
Lives for gear
 

i get to work with some trumpet and trombone players who regularly use plexiglas disks: they tell me the disks allow them to hear themselves better without me bringing them up in the wedges; they do however position the disks closer to their instruments and hence also to the mic capsules.
interestingly enough, i could not notice that this would affect the mic's behaviour (much); i've been using but dynamic mics in these situations though and mostly on rather loud stages so i cannot comment whether and how results would be when using more sensitive/high output condenser mics...
Old 19th January 2020
  #6
Gear Maniac
 

As others have said - these are simply a 'foldback' reflector popular with Trumpet and Trombone players, and are not intended to help the Sound engineer in any way apart from reducing the need for foldback from speakers (always a good thing). They work fine without noticeable side effects on a SM58 or similar mic, but when the same player turns up at a Broadcast where the Sound Engineer is giving them Ribbon Mics (or any side-address condensor) and they fudge some way of positioning their disk behind it without the engineers being aware, the resultant comb-filtering can be quite strange!
Old 19th January 2020
  #7
Super Moderator
 
Remoteness's Avatar
These Plexiglas disks are intended for additional 'foldback' for the musicians.

In my experience, these Plexiglas disks also help splay the horn blasts by spreading the sound wide, affecting the direct sound blast from their horns.

That being said, I have created Micro Gobos that do a similar thing depending on which side of the Micro Gobo you use. My Micro Gobos have a hard and soft side.

When using them with Royer R121s or similar figure 8 mics, I use the (foam) soft side.

I attached a couple of images that include my Micro Gobos placed behind the horn mics.
Attached Thumbnails
Plexiglas around microphones? Please explain!-09-12079294_10153716088829308_8541864616442925216_n.jpg   Plexiglas around microphones? Please explain!-09-12111984_10153716091654308_1340045183174973647_n.jpg  
Old 19th January 2020
  #8
It is correct that the plexiglas shield is intended to reflect the acoustic waves of the trombone or trumpet or saxophone back towards the player, allowing them to hear themselves.

Something left unsaid as of yet - one of the major concerns here on the part of the horn players is that they want to preserve their chops without overblowing through a long show and subsequently the chops get tired over time.

In bands where the trumpet players play both flugelhorns and regular trumpets, the shield helps a lot. As a very general comment I find a flugelhorn requires more preamp volume than a trumpet.

I don't mind it when horn players want to use the shields. I would like to do an A/B comparison at some point with and without the shield but after mixing a number of recordings where the horn players use shields, I don't notice any significant negative effects. I am using tight pattern dynamics most of the time.

The players I work with use the circular kind intended for a dynamic mic like an SM57. I love using ribbons on horns but have yet to work with a horn player who has a shield that is compatible with a figure 8 mic it seems. When I put ribbons up usually the horns don't use the shields then.
Old 19th January 2020
  #9
Super Moderator
 
Remoteness's Avatar
I agree with most of your post. What I disagree with is the use of these Plexiglas disks for saxophone. Not sure how they would help in that situation due to the positioning on the microphone.

When using a figure patterned microphone on trumpets and trombones I like to use my Micro Gobos for this task when applicable. They work well for my live performance captures.


Quote:
Originally Posted by BeerCheeseNPolka View Post
It is correct that the plexiglas shield is intended to reflect the acoustic waves of the trombone or trumpet or saxophone back towards the player, allowing them to hear themselves.

Something left unsaid as of yet - one of the major concerns here on the part of the horn players is that they want to preserve their chops without overblowing through a long show and subsequently the chops get tired over time.

In bands where the trumpet players play both flugelhorns and regular trumpets, the shield helps a lot. As a very general comment I find a flugelhorn requires more preamp volume than a trumpet.

I don't mind it when horn players want to use the shields. I would like to do an A/B comparison at some point with and without the shield but after mixing a number of recordings where the horn players use shields, I don't notice any significant negative effects. I am using tight pattern dynamics most of the time.

The players I work with use the circular kind intended for a dynamic mic like an SM57. I love using ribbons on horns but have yet to work with a horn player who has a shield that is compatible with a figure 8 mic it seems. When I put ribbons up usually the horns don't use the shields then.
Old 1 week ago
  #10
Here for the gear
 
Lone Trombone's Avatar
 

Quote:
Originally Posted by avillalta View Post
that's a cheap way to have acoustic-foldback so that the player can hear her/himself
I played trombone in a 12 piece Motown band for 20 years, and the trumpet player and I used these early on as basically our monitors. They were 10" or 12" with a center hole to fit the SM57 mics we used. This allowed the horn section wedges to have more of the tenor and bari saxes (using sm58 mics) in the monitor mixes.

They also had the added benefit of being able to adjust the direction of the sound of the bone/trumpet a bit if it needed to be moved away somewhat from the 4 vocalists on the front line with us.

Later on all 4 horns switched to wireless on-horn mics, so we stopped using them of course. Added benefit of being mobile also allowed avoiding singers ears or mic bleed.
Old 1 week ago
  #11
Lives for gear
 
tourtelot's Avatar
Oh, funny. All about the brass.

My eldest daughter, who is a cellist, tells me that their section was always the ones to call for plexi shields to help keep their hearing intact. From the racket the brass made.

D.
Old 1 week ago
  #12
Gear Addict
 

If trumpet players can't hear themselves they're probably the only ones who can't!!
Old 6 days ago
  #13
Quote:
Originally Posted by tourtelot View Post
My eldest daughter, who is a cellist, tells me that their section was always the ones to call for plexi shields to help keep their hearing intact. From the racket the brass made.
Indeed. I can confirm that getting blasted by the trombones is an occupational hazard for section cellists. Some actually wear ear protection.
📝 Reply
Topic:
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.


 
 
Slide to join now Processing…
🖨️ Show Printable Version
✉️ Email this Page
🔍 Search thread
♾️ Similar Threads
🎙️ View mentioned gear
Forum Jump
Forum Jump