So i finally start treating my room tomorrow :D

jenson

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Haha...thanks a lot. To be honest, I had my moments of doubt today. The usual ones, kind of " did I bite more than I can chew" types. The most difficult part was cutting that geowool. And those irritating fibers stick everywhere. It is such a pain, that iam dreading even starting tomorrow with all the cutting :(
You are indeed a badass :)
 
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fLUX

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Very nice work there @Yelamanchili manohar aka badass babua.

I had a SIY ( See it yourself) experience with bass traps , they had prepared cylindrical cones with the bass trap material then prepared a wooden enclosure , placed the cones and were then stuck to each other via an industrial glue. The fabric of choice was then stapled to the wooden frame tightly and finally entire unit was raised and then same glue was used to make them stick to the wall.

Seemed easy peasy watching it, but I know if I had to do it then either the bass trap or me would have been thrown out of the house for certain.
 

Hari Iyer

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My suggestion as below,
- Add 100gm to 300gm additional Recron fiber stuffing to the TL line to reduce LF resonance.
- the 65 Hz dip correspond to the floor reflection and is a comb filtering issue imo. Try temporally throwing a thick bed or foam on floor to check if that helps.
 

sud98

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I used black spandex, worked from a maintenance perspective as well as from a durability perspective for my bass traps. Its easier to build the frame first but I had a lot of issues in maintaining the triangular pieces esp. while putting them in the frame, so no easy options.

Use gloves/goggles and long sleeves, if geowool is anything like rockwool which is super itchy.
 

Yelamanchili manohar

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Any further updates ;)
Guess you got busy with Navaratri celebrations :D
Hi dinesh :)

Been away travelling for my daughters vacations. Should resume work on the 20th once iam back. By the way I finished the right corner trap too. Now only the back trap, behind the listening position is remaining now. And I already got the wrapping fabric in turquoise. So should be 2 days more work at max :)
 

hpdinesh

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Hi dinesh :)

Been away travelling for my daughters vacations. Should resume work on the 20th once iam back. By the way I finished the right corner trap too. Now only the back trap, behind the listening position is remaining now. And I already got the wrapping fabric in turquoise. So should be 2 days more work at max :)
Thank you for the update and sorry to bother you on your vacation.
Good to know that the front corner trap is done. Will PM you once you complete the back trap too :)
 

Yelamanchili manohar

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Long overdue update, been away on vacations and just finished the backtraps yesterday. The below was done :

2 corner traps behind the speakers, close to 3 feet wide at the mouth, and 2 feet deep at the apex of the triangle.

1 trap behind listening position, 8 feet wide x 8.5 feet high x 1 feet deep.

Couldn't stop my excitement to have a listen. But please bear in mind that iam listening after almost 25 days. First impression on female vocals from Annette askvik and Adele was WOW, the clarity definitely improved. But the bass still sucked at times to be honest. I was sure that iam still having my old suckout at 60hz and reverb in the bass. But didn't bother to measure yesterday.

Come today, added 4 nos of thin panels at side wall 1st reflection points, with supposedly 50% diffraction and 50% absorption, all in the upper midrange to treble region. And the improvement in vocal clarity is stunning. Iam actually over the moon right now, except for the bass which still sucks
:(


So finally I started measuring today with REW, and my RT60 time above 200hz is already close to 300 ms. Though some bass frequencies are still close to 500ms. I think I need more bass absorption to be added. I have 2 nos of 3 feet wide alcoves next to the back bass trap at either sides. I could this time use lower density rock wool at 60kg / cu.M to fill those upto 4 inches deep, but not sure if adding anymore absorption will be detrimental. Iam happy that the room is still very live sounding.

By the way, the way I built the panels, I've kept a consistent 2 inches gap between the geowool and the edge of the wooden frame, so that I could cover them with rocksul 370 or acoustic foam as required. So I still have this option to reduce RTA60 further in the higher frequencies. But the adamant RTA 60 in the below 200 hz region, is really proving beyond my ability to address.

So here are the pics of the room ( sorry for the mess, I live in a flat, so I've been chopping wood as well as 520 kgs of rockwool in the same room for sometime now
:D
)

I can post graphs tomorrow if anyone is interested. Though I should have ideally taken measurements of the empty room which I stupidly couldn't. So my measurements only start after the addition of the 3 bass traps.

IMG-20211028-WA0012.jpg IMG-20211028-WA0011.jpg IMG-20211028-WA0010.jpg IMG-20211028-WA0009.jpg IMG-20211028-WA0008.jpg IMG-20211028-WA0007.jpg
 

Decadent_Spectre

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Can you post your RT60 graph?

My friend just a word of caution (which you must be aware of), as the bass rises the mid range clarity falls. All else equal.
 

Yelamanchili manohar

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Someone might wonder, why all this struggle with enormous bass treatments, when I can play my pmc here, and they will not excite this room in the bass as much :D

The pmc have their place with fast paced music, and the most foot tapping music I've ever had. But these present speakers, have a weight, clarity and presence, that I just love. So the idea is to treat the room to live with them long term, for all genres of music :)
 

Yelamanchili manohar

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Can you post your RT60 graph?

My friend just a word of caution (which you must be aware of), as the bass rises the mid range clarity falls. All else equal.
Very true....that is why iam still considering adding more bass traps at the moment :)

Will post a pic of my present RT60 in a minute.

On an other note, do you think I should be measuring RT30 instead and multiply by 2, as my room is small at 11.5 x 15 feet.

And also do you think, if I had added 60 or 100 kg / cu.m rock wool , instead of the 160 kg / cu.m geowool that I've used, would I have had a better bass absorption below 100hz, leading to a lesser cancellation at 60hz please. Please let me know. Thanks :)
 

Decadent_Spectre

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RT60 is what I do, but I used to only measure with the Omnimic, I am not familiar with REW.

Bass needs mass period with the right material. I am not familiar with geowool but rockwool is the common used item and would stck with that. A few years ago I heard of people using some form of denim to absorb frequencies as an alternative that was not toxic.

Is cancellation really a absorption issue? Wouldn't you need to move the subs or adjust the time/phase for this? SBIR perhaps?

In any case I know you don't want to hear this but glasswool. Believe it or not it is what I used and works wonders.
 
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