How to quiet your impact screen?

[FaultyClubs]

This is a follow up to my comment above about club versus screen noise. I was surprised my wife thought my club was louder since I had always thought the opposite. So I had no choice but make some actual measurements. I've included graphs of the results below.

On the standard time graph (left side) you can see the club noise followed about 60ms later by the screen impact. It is obvious the club is much quieter and contains higher frequencies than the screen.

The inset graph (right side) shows a 3D plot of time versus loudness versus frequency. Time runs from the back to the front. Frequency runs from low on the left to high on the right. From that graph you can see the club impulse with a tight group of lower amplitude and placed in a higher range of frequencies. The impact screen then follows with this massive thump consisting of a heavy bias to lower frequencies. Those are the "CRACK!!" of the club and the "THUMP!!" of the screen respectively. In this case about a 20dB difference .

We're more sensitive to frequencies in the mid 1-5k range than below 1k so my wife initially reacted to the "Crack!" sound off the club. However once she concentrated on the total sound volume she quickly agreed the screen was louder. It just didn't bother her as much. So there's actual measurements and then there is psycho-acoustics.

Hope this helps rather than confuses.

[Ironstrokes]

This is a follow up to my comment above about club versus screen noise. I was surprised my wife thought my club was louder since I had always thought the opposite. So I had no choice but make some actual measurements. I've included graphs of the results below.

On the standard time graph (left side) you can see the club noise followed about 60ms later by the screen impact. It is obvious the club is much quieter and contains higher frequencies than the screen.

The inset graph (right side) shows a 3D plot of time versus loudness versus frequency. Time runs from the back to the front. Frequency runs from low on the left to high on the right. From that graph you can see the club impulse with a tight group of lower amplitude and placed in a higher range of frequencies. The impact screen then follows with this massive thump consisting of a heavy bias to lower frequencies. Those are the "CRACK!!" of the club and the "THUMP!!" of the screen respectively. In this case about a 20dB difference .

We're more sensitive to frequencies in the mid 1-5k range than below 1k so my wife initially reacted to the "Crack!" sound off the club. However once she concentrated on the total sound volume she quickly agreed the screen was louder. It just didn't bother her as much. So there's actual measurements and then there is psycho-acoustics.

Hope this helps rather than confuses.

Nice work, that's really cool actually seeing it on the graph like that. Sounds like some sort of room high frequency acoustic buffer is needed for the club, but what can be done around the screen is the big question. I'd be interested what the changes in decibels are with some memory foam behind it, if that makes a difference at all

[Boerdoc]

Ok, I want one of those. How did you measure that? What equipment and where was the mic placed? Where are the db values?

[FaultyClubs]

Iron: Yeah, higher frequencies respond better to sound absorption and in any case don't transmit out of the room easily (assuming no cracks/openings and doors are solid). The lower frequency screen noises are a lot harder to deal with since at low frequencies any sound absorption material needs to be extremely thick (think several feet, not inches!). Best not to generate the noise in the first place.

I have the HQ screen but with a heavy canvas backing. The backing material and how it is hung is definitely a factor. The quietest would probably be netting. My noise levels aren't a problem so I've never looked into it though.

Boerdoc: I measured on a PC using ARTA (I think there is a free demo of some sort) and an expensive calibrated microphone. The mic was out in the room, similar distance from club and screen. One of the graphs shows dB but it is normalized and in any case not comparable with an SPL meter's readout for various reasons. I hesitate to include SPL readings since easy to produce meaningless numbers.

But FWIW here's a SPL graph, C weighted, Fast setting. Various 3-wood, Driver and 6 iron shots. The driver sounds way louder than the 6 iron but the total noise doesn't change much since it is screen dominated. A SPL meter won't show the club and screen separately since the integrating time is too long. I used a calibrated mic and REW software on a PC for this (Room EQ Wizard is free). If you use a PC make sure the soundcard isn't doing any processing (EQ, compressing, levelling, boosting etc) and doesn't clip the input stages when hitting. And of course you have to calibrate the input chain to get valid readings.

EDIT: I should say, ignore the first two readings since I was warming up and didn't hit them hard. And the third because it was a mis-hit. The rest were fine.

[Joko]

I had recently moved my HQ screen to the corner and further back towards the wall (17" or so from wall) - it use to be in the center of the room and was probably 4' from the wall. I also made the screen smaller by using some tarp clips w/bungees.

Now I've noticed the screen sounds like a shotgun when struck by a ball, like mentioned above. Before it was actually fairly quiet. I'm wondering because it's closer to the wall if that isn't causing added sound? I am trying to re-adjust the tension on the screen but it seems to be as tensioned or less tensioned as it was previously when it was quieter.

I ordered a NET to put behind it, but now I'm wondering if I should also put some type of foam either between the screen and netting or on the back wall.

Any thoughts? It was definitely not this loud previously and is relatively uncomfortable to hit on now.

Thought I would add my progress here for any interested. I did change the tensioning slightly, which seemed to help, but also I added the 2 1/2 inch eggcrate foam against the back wall. I can't exactly say which caused more of a sound difference, but it no longer sounds like a bass drum when hit. No net at the moment.

[Ironstrokes]

Thought I would add my progress here for any interested. I did change the tensioning slightly, which seemed to help, but also I added the 2 1/2 inch eggcrate foam against the back wall. I can't exactly say which caused more of a sound difference, but it no longer sounds like a bass drum when hit. No net at the moment.

Very interesting, is the foam touching the screen at all? How far away is the wall from the screen, curious

[Joko]

The screen is about 18 inches or so from the wall. The foam is attached to the wall, and I don't believe the screen hits the foam, although I haven't had someone sit back there and watch. But I would be surprised.

[Greasegun]

Pretty good stuff in this thread. Does anyone here know what is the most quiet impact screen available?

[Ironstrokes]

Pretty good stuff in this thread. Does anyone here know what is the most quiet impact screen available?

Not sure if its the quietest or not but was surprised how quiet Carl's premiem screen was compared to the HQ2 and supertex. Heres a video i made a sound test of the HQ2 vs. the Carl's premium.

[Greasegun]

Wow big difference there.