I've listened, THIS BETTER WORK

[swgiust]

OK, so I have a room null at about 63hz. Been messing with my SMS-1 and my
PB12/Ultra-2. Can only get it smoothed out with major boost in the EQ. +6 on
three bands. (not good)

So, I've been debating the best way to fix things. Option 1 add another subwoofer. Which by far is the most fun option (and the most exspensive) or
option 2 invest in some good room treatments.

I had seen GIK acoustics had a special listed here a while ago and when I
contacted them, they gave me the same deal. I purchased 4 Tri-Traps and
6 242 acoustic panels. Bright red (Go Huskers!).

My hope is that by treating the room I can smooth out my bass response. As
well as treating some first level reflections. Giving me an overall better sound.
I do have some homade tube traps and some panels. I will find some secondary
locations for them.

So, opinions, did I do the right thing? Thoughts? Suggestions? Ideas?

[Liaury]

So, opinions, did I do the right thing? Thoughts? Suggestions? Ideas? :D I can't wait for your opinions, thoughts, suggestions, and ideas.

[ThomasV555]

Can you move the sub?

[Jesse S]

A null cannot be corrected with any amount of eq boost. So it's not a null. Just move the sub somewhere else.

[swgiust]

I have had the sub in 4 locations. Front left corner, Rear right corner,
1/2 down left wall and current position 1/3 down the right wall. My room
is perfectly square. So I guess I felt room treatments were the best option.
I know you can over treat a room, but I feel I am far, far away from that.

Room is 18' x 18'. Has a vaulted ceiling 13' high. Peak runs from left to right.
Left wall is solid with a door, right wall is entirely glass. Lower windows are
covered with heavy curtains. Front wall is solid. Back wall has a set of glass
dutch doors going outside. Also covered with curtains.

So if you look at all the wrong things a room can have, I have most of them!

[Nick250]

Just wait for the treatments. It was a night and day experience for me.

Nick

[cyberbri]

Once you get the treatments in the room, you'll notice a big difference. But if the dip (as opposed to a null) is still there, you can add an eq like the BFD ($100) or the more expensive SMS-1.

I got traps (a little less than you) and treatments, and it improved the sound quality but I still had a number of dips/peaks.

Here's after traps + before BFD, and after adding the BFD:
http://gallery.avsforum.com/data/503/graph.JPG

That's done at 1/6 octave. Actual response is within a 2-2.5dB range for most of the 35-90Hz range, with a rise below that.

[hifisponge]

I don't mean to be a pesimest, and I may be wrong (as I'm not familiar with the GIK bass traps) but most bass traps have to be huge to do any effective absorbsion of low bass frequencies. Even the largest ASC Tube Traps (20" in diameter) are most effective at around 250Hz. The fact is that low bass frequencies have huge wave lengths and it typically takes an equally large (deep) absorber to make any difference in standing waves. Even though GIK claims on their website that their traps work down to 50Hz, I would imagine that it isn't doing much down that low.

Again, I may be wrong, and I hope I am. I look forward to hearing your results.

PS - You may need more than four of the traps if you hope to make difference. Measure the results and if you see a slight improvement in your dip, get more of them to stack on top of one another.

Edit: I stand somewhat corrected. The Tri-Traps appear to be more effective at low frequency than a the largest tube traps, though they are still most effective at around 125 - 250Hz, as I suspected.

[armystud0911]

So what is it in their design that makes them so effective? Is there a way to make a DIY version that replicates these properties?

[craig john]

So what is it in their design that makes them so effective? Is there a way to make a DIY version that replicates these properties?

http://forum.studiotips.com/viewtopic.php?t=535
http://forum.studiotips.com/viewtopic.php?t=536

Craig

[Ethan Winer]

low bass frequencies have huge wave lengths and it typically takes an equally large (deep) absorber to make any difference in standing waves.

Yes and no. You don't need 100 percent or even 50 percent absorption to make a real improvement in peaks and nulls and ringing. For example, if a room boundary reflects perfectly and creates an infinitely deep null, adding absorption that is 25 percent effective raises that null from infinitely deep to less than 15 dB deep. The demo video on my company's site shows a real improvement in the response of a small room all the way down the the 40 Hz lower limit we tested. So it's definitely possible to make a real improvement at low frequencies with good bass traps, even if they're not hugely thick.

--Ethan

[myfipie]

I don't mean to be a pesimest, and I may be wrong (as I'm not familiar with the GIK bass traps) but most bass traps have to be huge to do any effective absorbsion of low bass frequencies. Even the largest ASC Tube Traps (20" in diameter) are most effective at around 250Hz. The fact is that low bass frequencies have huge wave lengths and it typically takes an equally large (deep) absorber to make any difference in standing waves. Even though GIK claims on their website that their traps work down to 50Hz, I would imagine that it isn't doing much down that low.

Again, I may be wrong, and I hope I am. I look forward to hearing your results.

PS - You may need more than four of the traps if you hope to make difference. Measure the results and if you see a slight improvement in your dip, get more of them to stack on top of one another.

Edit: I stand somewhat corrected. The Tri-Traps appear to be more effective at low frequency than a the largest tube traps, though they are still most effective at around 125 - 250Hz, as I suspected.

Oh yes you are correct they do EXTREMELY well at 125 to 250HZ, but at 60HZ you are STILL looking at 8.93 Sabins and 6.53 at 50HZ. If you where to translate that to a absorption coefficient that would be 1.12 at 60HZ and .82 at 50HZ. I dare you to find any bass trap that touches that number. Heck there are products on the market that brag the same 8.93 at only 250 Hz. :D
note: absorption coefficient numbers are for "A" and "E" mount testing and I am only showing this because some people understand that number better. NO FLAMING ME. :eek: :D ;)

Glenn

[kgveteran]

So what is it in their design that makes them so effective? Is there a way to make a DIY version that replicates these properties?

I built two (18"x48").They work great.Biggest effect is the reduction in overhang or ringing.Seems to make the bass sound a bit quicker.http://www.geocities.com/jonrisch/basstrap.htm

Cost was 175.00 for two.

KG

[Nick250]

PS - You may need more than four of the traps if you hope to make difference. Measure the results and if you see a slight improvement in your dip, get more of them to stack on top of one another.

Edit: I stand somewhat corrected. The Tri-Traps appear to be more effective at low frequency than a the largest tube traps, though they are still most effective at around 125 - 250Hz, as I suspected.

And just to add to the confusion, my setup is in a large living room, dining room and entryway combined . There is just one ninety degree corner anywhere close to sub and speakers. I ordered four Tri Traps. It turns out I only needed one of them! The bass went from somewhat boomy to tight and musical. It was one of those night and day things. I was amazed.

Nick

[mcallister]

so any update on how these are doing in your room?

[swgiust]

They come today. I will be messing around this weekend and will give a full
report asap.

[mcallister]

awesome!!! I'm about to pull the trigger on some tri traps but am waiting to see your review. I have a nasty null between 60-80Hz.

[swgiust]

:mad:FedEx delivered my 6 panels and 2 of the 4 Tri traps I ordered... :mad:

I'll be setting them up tonight, but can't really do any serious tuning untill
the other traps come :mad: :mad: :mad:

[Tim916]

You will not regret your decision. Not only do bass traps help smooth the bass at the primary listening position, they smooth the resonse at all listening positions - something that the standard sms-1 does not do.

[swgiust]

OK FedEx finally delivered my last two TriTraps. Have them installed in my front two corners (2 in each corner). I ordered them in red, it's a Husker thing, and they are quite the sight to be seen! I also ordered 6 of the panels. I have 1 behind each of my front speakers, 1 below each of my surround back speakers, and 2 on my left wall. The other wall is mostly glass, I installed 3 of my homade panels along that wall behind a heavey curtain, which is closed 99% of the time. I have 2 homeade tube traps in the rear corners.

I have not spent alot of time messing with things yet, but after I had all in place,
I ran my SMS-1. Ruler flat from 200hz down to 40hz. We're talking 2db +- max.
I have a slight hump at 40hz. About 6 db and then it gently rolls off below that.
I have not adjusted much for the 40hz hump, but I will play around today and
see if I can smooth it out.

So remember, I had a 9-10db dip at 63hz which is now gone. Pretty impressive.
I will try to take a picture of the screen so you can see the bass curve display.

Right out of the box I would recommend these traps. They did what they were supposed to do. I am going to play around with them all weekend and I will post my results on Monday.

[billybob_jcv]

Sounds like the title of this thread should be changed to "I've listened, IT WORKS!" :)

[myfipie]

OK FedEx finally delivered my last two TriTraps. Have them installed in my front two corners (2 in each corner). I ordered them in red, it's a Husker thing, and they are quite the sight to be seen! I also ordered 6 of the panels. I have 1 behind each of my front speakers, 1 below each of my surround back speakers, and 2 on my left wall. The other wall is mostly glass, I installed 3 of my homade panels along that wall behind a heavey curtain, which is closed 99% of the time. I have 2 homeade tube traps in the rear corners.

I have not spent alot of time messing with things yet, but after I had all in place,
I ran my SMS-1. Ruler flat from 200hz down to 40hz. We're talking 2db +- max.
I have a slight hump at 40hz. About 6 db and then it gently rolls off below that.
I have not adjusted much for the 40hz hump, but I will play around today and
see if I can smooth it out.

So remember, I had a 9-10db dip at 63hz which is now gone. Pretty impressive.
I will try to take a picture of the screen so you can see the bass curve display.

Right out of the box I would recommend these traps. They did what they were supposed to do. I am going to play around with them all weekend and I will post my results on Monday.

HECK YES!!!!!!!!! Thank you very much for the report back. When you get a moment please send me a couple pictures if you would. My guys here love to see them.

Glenn

[mcallister]

so how are things going swgiust? I ordered 4 tri traps today. Anxious to see if they will help my enormous null between 60 and 80 Hz.

[Rupert]

so how are things going swgiust? I ordered 4 tri traps today. Anxious to see if they will help my enormous null between 60 and 80 Hz.

breedingamies,

Did your 4 tri traps help?

[cyberbri]

so how are things going swgiust? I ordered 4 tri traps today. Anxious to see if they will help my enormous null between 60 and 80 Hz.


Is it a null, or are there two peaks, maybe modal, at 55 and 85Hz? A null won't increase in volume at the same level of the increase overall. If you turn up the volume 3dB, and the "dip" goes up 3dB as well, it's not a null. More likely you just have some peaks.

The tri-traps will help a bit with fr, mainly the ringing and boominess, but to really flatten it you'll need an eq.


Here's my room, before (red) and with 2x "244" panels in each front corner (blue). One Tri-trap is about equal to two of the 244s. Note that this is both sub and mains, with no eq. Peaks at 45Hz and 75Hz, which I brought down with an eq.

15-500Hz
http://farm1.static.flickr.com/134/379646422_c7eab0cf65_o.jpg


Here's after eqing, combined sub and mains response:

15-200Hz
http://farm1.static.flickr.com/130/379646377_10d38b2f75_o.jpg

[ribbit]

get the second sub just because it's fun
then get the room treatments.

if you get the room treatments FIRST, there might not be any reason to buy a second sub