GIK Acoustics absorption panels

[Dialectic]

My issue has now been resolved thanks to @GlennGIK and his team. Will be posting before and after measurements this weekend, although perhaps unsurprisingly in light of my use of well-behaved D&D 8Cs, the FR measurements don't look that different.

In terms of RT60 times and subjective imaging properties, however, the improvement has been enormous, and the sound that I'm getting through the 8Cs and BACCH is as good as I've heard from any system anywhere in all respects except for bass below 25 Hz.* In the final analysis, there is no replacement for displacement; subwoofers will be added in due course.

* I have not heard the system assembled by @dallasjustice, which is assuredly better in certain respects. The lack of any compromise for domestic considerations in his system was an inspiration to me, and his comments on the poor cost-effectiveness of diffusers was instructive as I tried to figure out whether to include diffusion or focus on absorption.

 

[MRC01]

Glad to hear you got this resolved with GIK. My room treatments are a mix of DIY (built my own large tube traps), bass resonators (GIK Scopus T70s), bass traps (RealTraps MegaTraps) and RPG acoustic foam. I didn't notice a significant difference in build quality or appearance or price between GIK and RealTraps. Both had good customer service both before & after the sale. I would buy from either again without hesitation.

PS: I also found these room treatments improved the sound much more than the FR curve suggests. Yes, the FR improved, but I could have done most of the FR improvements with EQ, and that alone didn't sound nearly as much better as the room treatments. The time response (CSD etc.) really makes a big difference. I still did use EQ, but after the room treatments the EQ is gentler and more transparent than it otherwise would have been, and is just the icing on the cake.

 

[Dialectic]

I have had very good luck over the years with GIK. i always pay the upcharge for gilford fabrics as I like the look of this color. Also, they have good response to requesting room analysis and purchasing advice. I did this previously in my old house but now that i have moved and the dimensions of my room have changed I need to send GIK a message getting advice on how best to setup the pieces I have and augment accordingly. I know that some REW measurements would be required information to provide with my dimensions and picture but i've been very lazy lately not wanting to pull out that software and get it running again with my mac...

I also want to get my cloud mounted but my ceilings are 13 feet and my ladder does not make me feel super comfortable. I wonder how critical that is in my new room? Glenn, any advice based on this photo? Cheers.

View attachment 51694

I should have added above that the pre-sale service I received from Mike at GIK Acoustics was excellent, though my use case (8Cs + BACCH) perhaps results in an ideal configuration different from what would work best in a more conventional system.

@countbasey, your room looks very nice. Do you have any thoughts on how to get the panels hanging at precisely the same heights? I've found that difficult to achieve with picture wire.

 

[countbasey]

I didn't. i am using picture wire as well. im not super stressed about it and my wife does not notice either... I am concerned about my overall sound however. I tested the room with REW this weekend. you can see the issues I still have in my room below 250hz. I'm pretty pleased with what is happening above that.

I can use Roon EQ to reduce that peak around 50hz but the dips at 80hz, 150 and 210 might need some serious HP

 

[Kal Rubinson]

I can use Roon EQ to reduce that peak around 50hz but the dips at 80hz, 150 and 210 might need some serious HP

You may be surprised but, if you fix the 50Hz peak, it may have a salutary effect on some of the dips.

 

[countbasey]

Good point. Unfortunately its impossible to me how i might take measurements in REW with the Roon filters in place to see this behavior. I really wish that Roon had the REW test tones playable or some integration of the two products to preview the results.

 

[MRC01]

So you need to weaken that 50 Hz peak and the 80 Hz null. Fix those first, then re-measure and see how much that helps the rest. IME, those swings are too big for EQ alone, you'll need room treatment. And you'll need narrow band treatment, not porous absorbers (which are wide band). Why? Because those modes are so strong, porous absorbers strong enough to weaken those strong modes, will deaden the entire room, due to their wideband response. Narrow band treatments means bass traps or resonators.

In my case, GIK Scopus T70 (resonators) were effective at weakening (lifting) a deep null I had between 70 and 75 Hz. And Realtraps MegaTraps were also effective. And I also use big tube traps, but they alone couldn't solve my resonance problems because they are porous absorbers, which significantly improve the overall bass response & spectral decay, but too much of them over-deadens the room.

Have you determined whether the peak or null is: (A) a room mode, (B) SBIR, or (C) LBIR? If it's (B) or (C), then re-arranging the speakers, room, listening position will help.

 

[QMuse]

Good point. Unfortunately its impossible to me how i might take measurements in REW with the Roon filters in place to see this behavior. I really wish that Roon had the REW test tones playable or some integration of the two products to preview the results.

You have 3 wav files here, one for each channel and 3rd when both will be playing. Play them in Roon and use REW RTA mode to record the response.

Watch this video to see the procedure.

 

[Kal Rubinson]

You have 3 wav files here, one for each channel and 3rd when both will be playing. Play them in Roon and use REW RTA mode to record the response.

I was going to suggest something like that. Good.

 

[countbasey]

Makes sense. i cannot open your zip on my mac for some reason but I can find a pink noise wav file and place it on my local server for playback through roon and make pink noise measurements with and without the Convolution filters/eq. Also, i didn't do pink noise measures in the previous results i did just the sine wave sweep. Should they should return similar if not exact results?

 

[countbasey]

So you need to weaken that 50 Hz peak and the 80 Hz null. Fix those first, then re-measure and see how much that helps the rest. IME, those swings are too big for EQ alone, you'll need room treatment. And you'll need narrow band treatment, not porous absorbers (which are wide band). Why? Because those modes are so strong, porous absorbers strong enough to weaken those strong modes, will deaden the entire room, due to their wideband response. Narrow band treatments means bass traps or resonators.

In my case, GIK Scopus T70 (resonators) were effective at weakening (lifting) a deep null I had between 70 and 75 Hz. And Realtraps MegaTraps were also effective. And I also use big tube traps, but they alone couldn't solve my resonance problems because they are porous absorbers, which significantly improve the overall bass response & spectral decay, but too much of them over-deadens the room.

Have you determined whether the peak or null is: (A) a room mode, (B) SBIR, or (C) LBIR? If it's (B) or (C), then re-arranging the speakers, room, listening position will help.

You can see my treatments in the photo on the previous page. I have monster bass, 244, corners, diffusers, and some alpha 4. I don't yet have a Scopus. Was looking yesterday at some T40s since they have more 40/50hz and the same 80hz as the T70. About how many might you think would be needed given that more=better i assume. Also the benefit of two way scatter seems like the obvious choice over 1 way but not sure in that gut feeling assessment. cheers.

 

[MRC01]

T40s should work well for your 50 Hz, but the lower the freq, the longer the wavelength, the more area it takes to make a difference, which is more units. The most important point is to use narrow band treatments, since you want to kill specific frequencies, not overdamp the entire room.

However, even more important is to move the speakers & listener position (e.g. measurement mic) around (separately) and see if the problematic frequencies also change. If so, you're dealing with SBIR or LBIR and you may be able to fix or at least weaken it with repositioning.

PS: example of what I mean by LBIR (listener boundary interference response): if your listener/mic position is 4' in front of the back wall, then you'll hear a dip around 69 Hz. That's because the sound hits the back wall and reflects forward, total distance is 8', which is half a wavelength of 69 Hz, so the reflected wave partially cancels the direct wave at your listener position. This same distance is a full wavelength of 138 Hz, so you'll hear a boost there as it constructively interferes. In this example, LBIR gives you a cut at 69 and a boost at 138. If you experiment with mic positions closer or further from the back wall, and you see those 69 and 138 freqs shift, you know it's LBIR. If they stay the same, they're caused by something else. You have a sharp dip at about 79 Hz. If your listener position to back wall distance is about 3.5 feet (1/4 the wavelength of 79 Hz, for 1/2 wavelength total distance traveled with reflection), then LBIR might be causing it, and you can experiment to find out.

 

[whhenyuan]

we have also acoustics absorption panels material, More details , kindly visit www.1st-acoustics.com

 

[cassisb]

Hello, thanks for this thread. I hope you are all doing well in these uncertain and intense times! We purchased two PIBs with a roof. They just arrived today and we are quite disappointed. One of the PIBs -- the hinges - because the screws were too near the edge - were ripped out. On both PIBs half of the screws are missing. Half of one of the hinges is dirty with deep black marks that can't be cleaned. The wooden cross panel on the roof is cracked and one of the side pieces is not secured. We were excited to get these for an upcoming voiceover project. They do seem to work well - the sound is dry but we can't try the entire construction out because of the broken hinge. Hopefully the customer service rep will reach out tomorrow. We sent him the pix that we are attaching to this post here. We're tempted to send all of it back. Not sure how to deal with this. We're glad to see Glenn, the owner, reading this thread. ;-) Hello from Berlin!

 

[txbdan]

Wow, i can't fathom how that would get by a final inspection. Assuming there is a final QC inspection?...

I've been in talks with GIK about my room and they've been very responsive and helpful. It must be extremely frustrating for the owner to have his customer service and design teams doing good work only to have it spoiled with shoddy execution.

 

[freedomgli]

It must be extremely frustrating for the owner to have his customer service and design teams doing good work only to have it spoiled with shoddy execution.

Or poor packaging. Or poor shipping. Or any combination of the above.

 

[txbdan]

Or poor packaging. Or poor shipping. Or any combination of the above.

Nope, not with those hinges screwed so close to the edge. Somebody missed their marks there.

 

[dionisp]

Which GIK model is that?

 

[Promit]

Look like that’s the portable isolation booth. My new impressions also arrived yesterday and look great, sorry to see others having problems. I’ve always liked working with GIK.

 

[dionisp]

I also have very good customer experience with GIK Europe.