Effects of speaker placement & Room treatment

[sound_cycle]

1. Well said sidvee,this is the one and only solution we have currently i.e (room treatment/proper placement) to tame room modes or early reflections and to see that we do get clear sound from the speakers,and ofcourse with proper experimentation.

Wrong @ one and only (you mention two BTW)

Among others there is DRC, others use cables/ equipment matching and other tricks

2.REW is the best software for measuring and analysing room and speaker responses,as all agree but they are not good at any correction,to achieve good results analog correction is prefered.

Please substantiate what analog correction and why it is to be preferred over what software, for clarity

In the interim, the assumption that software is not good at any correction is just plain wrong.

I thank you for agreeing with what I said a few posts above http://www.hifivision.com/diy/61250-effects-speaker-placement-room-treatment-4.html#post677311

REW will give you the graphs and measurements, before and after treatment. For instance use the impulse plots to figure out and kill early reflections, or to figure out if your bass traps or broad band absorbers are doing anything. Or if your DRC is doing anything for that matter

REW can do but however is not great at correction, I did not quite figure out how to set up the filters correctly and used the fb2k plugin which was very limited.

4. For taming freq below 300hz,is either to have thicker absobers (6 to 8 inches) on all corners ground to ceiling though results are not fully achieved or can place another sub opposite to the existing one (center of the wall) or even have 4 subs to even out the bass in all corners of the room,so that you dont have to increase the vol which results in boomy bass and in turn standing waves.

Wrong.

I leave it to you calculate the depth of the the "thicker absobers". I am sure you are aware that you would need them to be 1/4 of the wavelength you are trying to absorb, and also that killing by absorption is not the only way.

The notion that standing waves are a function of volume is also wrong.

just reading laws of physics about sound and chasing illusion is not the only solution,we have to implement methods and take certain measures to correct them,as pointed out by sidvee and me you just have to follow them,thats the only way we can listen to proper sound.

How/ Why do you assume that I have done nothing ?

As for the obvious troll(s), nice try, but failed attempt at getting a response.

I am not a mod, but would like to politely point out that reading hfv has been an enjoyable and informative experience and would request you to kindly keep that in mind while posting.

I am curious have you posted your set up / treatment thread here ? Maybe I could understand your experience better if you would please point me to it.


ciao
gr

Not sure on room dimensions being discussed here. Is it 14' x 11'?

Yes. But no / limited room treatment. I understood the room to be multipurpose ie. not exclusively a listening room.

I currently have Ascendo C8R speakers in my room placed at 4' from the wall behind the speakers on the short wall and at 28" from side walls. <snip>I have had many senior FM's listen to my setup and they all more or less agree.

I much admired that pic on your back to valves thread. The treatment you described seems very comprehensive to me. I don't have anything remotely like it in place.

I have realized a passable soundstage and what I think is decent imaging. Unsurprisingly nothing even close to the holographic imaging you describe though. Fatigue free, boom free listening yes

May I request to please let me join in if you should have a listening session at your place. From my pov it would be enlightening, in figuring out what I am missing in my setup and maybe where I should head. I realize it might be an unattainable benchmark though !

Thanks

ciao
gr

But the first and easiest thing to start off with is placement, since it doesn't cost anything.

And to add (maybe needlessly ?) patience and precision

ciao
gr

 

[frend2001]

Hi Dear FMs,

Here's asking some tips from you.

I've a passive 100w sub from sony. Currently it's placed below the speaker.

My problem is the in the room there's no bass and I don't want thumping bass.

I'm simply looking for deep and tight bass that can be extracted from this sub.

I'm sure it's a placement issue.

Please guide.

View attachment 19867

 

[prem]

Move the sub to the right side corner. It will load the room better. In the new position you may have to readjust the crossover and the vol

 

[sidvee]

May I request to please let me join in if you should have a listening session at your place. From my pov it would be enlightening, in figuring out what I am missing in my setup and maybe where I should head. I realize it might be an unattainable benchmark though !

Thanks

ciao
gr

Yes sure will let you know, however due to a busy schedule it will not be any time soon.
Cheers,
Sid

 

[rajesh srinivas]

Wrong @ one and only (you mention two BTW)

one and only is related to both ((room treatment and speaker proper placement)) thats why i mentioned it in bracket refering to both.

Among others there is DRC, others use cables/ equipment matching and other tricks

DRC is waste of time coz its endless tweaking and it does justice to one perticular seating position you move to another seating its scrape.

Please substantiate what analog correction and why it is to be preferred over what software, for clarity

Analog correction is refered to acoustic room treatment we do physically,it also includes building a room especially to overcome standing waves of lower freq,its a universal/comman treatment to any position you are seated and also applies to any music or movies you watch,once set correctly it will serve your purpose for years without any dips or peaks or any room modes.

In the interim, the assumption that software is not good at any correction is just plain wrong.

software correction as i said earlier is endless tweaking what you set your presets for one type of music or movies will not be good for another,by doing so you will be wasting a lot of time and efforts wherein the need of the hour is to enjoy listening what is played.

As given in wikipedia.org

Equalisation of the sound system to compensate for the uneven frequency response caused by room resonances is of very limited use as the equalisation only works for one specific listening position and will actually cause the response to be worse in other listening positions.

my suggestion to all hifimembers as already mentioned by many members is to get your room corrected with proper speaker placement and using the right acoustic treatment which can eliminate reflections and room modes as a one time solution..and enjoy to what is being played coz we spend so much of money, time and efforts in doing so..

Wrong.

I leave it to you calculate the depth of the the "thicker absobers". I am sure you are aware that you would need them to be 1/4 of the wavelength you are trying to absorb, and also that killing by absorption is not the only way.

The notion that standing waves are a function of volume is also wrong.

Thickness of absobers is to eliminate room modes,how much???its based on testing with test tones of different frequencies right from 25hz to 300hz till you feel that the boominess dissapeares or the other way is to add subs at different location to kill them.

I am not a mod, but would like to politely point out that reading hfv has been an enjoyable and informative experience and would request you to kindly keep that in mind while posting.

Hence follow to what is being said by moderators or members coz those are the only alternate ways and techniques that you can implement.

I am curious have you posted your set up / treatment thread here ? Maybe I could understand your experience better if you would please point me to it.

i am in the process of building a new HT, it will take time,will be doing it slowly step by step afcourse with hifi members help,i believe in not to leave any stone unturned,room for ht is in cleaning process,drivers have arrived soon will be posting a thread to start with...


Thanks
r/s

Hi Dear FMs,

Here's asking some tips from you.

I've a passive 100w sub from sony. Currently it's placed below the speaker.

I'm simply looking for deep and tight bass that can be extracted from this sub.

I'm sure it's a placement issue.

Please guide.

View attachment 19867

it cant by only the placement issue,but that can be the first step,the best way is to find out the best position of the sub wherein you are getting the maximum lows,you can try the crawling method.

deep and tight bass is of 2 different parameters,deep you can get with a ported box,and tight bass with a sealed one,dont know what type of box you have.

According to your taste a sealed sub will serve your pupose which can give tight bass but not punching,if you have a ported One cover the hole and try...

My problem is the in the room there's no bass and I don't want thumping bass.

no bass can also be that your amp is lacking power more details required to exactly point out the real problem..

thanks
r/s

 

[raghupb]

sidvee/rajesh/sdurani/sound_cycle - Nice meaningful analyses and suggestions.

sidvee - your reference room is simple and classy

Summing up room correction requires these things:
1. Means (moolah) - this one is easy and under my control
2. Method and Effort - partly under my control; yet to learn a lot
3. Opportunity - definitely not under my control; WAF will never happen

Next step is to install my newest acquisition (KEF R300s) and re-arrange furniture
In my opinion, speakers are active furniture. And they will be moving around a lot because of 2 mutts in the house.

Cheers,
Raghu

 

[Deleted member 79034]

it cant by only the placement issue,but that can be the first step,the best way is to find out the best position of the sub wherein you are getting the maximum lows,you can try the crawling method.

I have a follow-up question.

When should one work on sub-woofer placement for a typical home theatre in a living/bedroom.

Should it be when you have all the furniture/decor placement done? But then you would not want to drill holes in your wall to draw subwoofer wire.

 

[sidvee]

sidvee - your reference room is simple and classy

Thanks Raghu.
Cheers,
Sid

 

[prem]

Hi raghupb

You can also look at Franck Tchang resonators. They should take care of most room problems. For your room you will need a basic resonator and two silver resonators. His stuff is not cheap but works big time.

 

[raghupb]

Thanks Prem.

I don't think I will be allowed to add anymore stuff to the living room (also where the whole system is). Stands yes, anything else her response will be "Go fly a kite!"
This was the response when I mentioned DRC - "Duh, Reality Check!!"

Cheers,
Raghu

 

[prem]

I understand raghupb

The resonators are practically invisible though

Add a few rosewood cubes on any window panes that you have in your room. You can have it made locally. They cost practically nothing. The cubes are 1 cm with 1 mm holes in them. Google to see how they look. Use Indian rosewood also known as sheesham.

If there is a boom use one or two inverted wine glasses. Lots of guys in Japan use a lot of wine glasses for room treatment. It basically converts bass into higher energy thereby reducing boom. This is not to be confused with what people say glass adds brightness. Here in the inverted technique glass works differently. Use as thin a wine glass as possible.

For diffusion you can add a plant or two behind the speakers if space permits

Raghupb, arj on our forum has the resonators as well the rosewood cubes. You can connect with him to understand how these things work

 

[sound_cycle]

one and only is related to both ((room treatment and speaker proper placement)) thats why i mentioned it in bracket refering to both.



DRC is waste of time coz its endless tweaking and it does justice to one perticular seating position you move to another seating its scrape.



Analog correction is refered to acoustic room treatment we do physically,it also includes building a room especially to overcome standing waves of lower freq,its a universal/comman treatment to any position you are seated and also applies to any music or movies you watch,once set correctly it will serve your purpose for years without any dips or peaks or any room modes.



software correction as i said earlier is endless tweaking what you set your presets for one type of music or movies will not be good for another,by doing so you will be wasting a lot of time and efforts wherein the need of the hour is to enjoy listening what is played.

As given in wikipedia.org



my suggestion to all hifimembers as already mentioned by many members is to get your room corrected with proper speaker placement and using the right acoustic treatment which can eliminate reflections and room modes as a one time solution..and enjoy to what is being played coz we spend so much of money, time and efforts in doing so..



Thickness of absobers is to eliminate room modes,how much???its based on testing with test tones of different frequencies right from 25hz to 300hz till you feel that the boominess dissapeares or the other way is to add subs at different location to kill them.




Hence follow to what is being said by moderators or members coz those are the only alternate ways and techniques that you can implement.



i am in the process of building a new HT, it will take time,will be doing it slowly step by step afcourse with hifi members help,i believe in not to leave any stone unturned,room for ht is in cleaning process,drivers have arrived soon will be posting a thread to start with...


Thanks
r/s

I hope you will forgive me if I do not pursue this discussion with you further.

I am simply not worthy of your wisdom.

ciao
gr

 

[raghupb]

Actually with the current set of speakers B&W DM303s I don't have any serious LF issues. Need to check with the new set of speakers though.
Some blues tracks that I listen to thump one in a while; I just use tone down bass.

Most of the time I am not even seated in front of the system. My music listening happens when:
- working from home; seated at the dining table
- cooking (these days it is just cutting veggies or grating cheese as per instructions)

So sonic perfection is not really on my agenda. Music around the house; yes definitely.

Cheers,
Raghu

 

[prem]

Raghupb, that's how I too listen to music most of the times. I don't like to be seated always in front of the speakers.

 

[raghupb]

@prem

I will try out the wine glass experiment; should have some champagne flutes lying around.
As for the cube resonators, sounds very interesting (pun intended)
I have access to lots of wood from various species left over from furnishing my home. As my wife puts it; carpentry is not my passion but obsession.
Sheesam you say, any particular reason? Density?

Cheers,
Raghu

 

[prem]

Raghupb, I don't understand the science behind Franck Tchangs designs. All I know is it has to be Indian rosewood. Maybe density, maybe because it's a tone wood. But it works.

 

[sidvee]

@prem

I will try out the wine glass experiment; should have some champagne flutes lying around.
As for the cube resonators, sounds very interesting (pun intended)
I have access to lots of wood from various species left over from furnishing my home. As my wife puts it; carpentry is not my passion but obsession.
Sheesam you say, any particular reason? Density?

Cheers,
Raghu

Raghu, if you are trying the cube resonators I would be very interested as well, especially on glass. I basically understand the resonance principle, and realize that various materials in a room have difference resonating frequencies - which btw is firmly rooted in the principles of physics - so if you are considering any diy cubes please keep me in mind. I will share any costs you incur.
Cheers,
Sid

 

[raghupb]

sidvee/prem,

Prem has veered me into a confluence of 2 of my interests. Will definitely keep you guys in the loop. Don't worry about the costs.
I may not be able to get to experimenting anytime soon. Work pressure will be crazy over the next few months.

Cheers,
Raghu

 

[prem]

Hi Sidvee

The rosewood cubes cost next to nothing. I think Magma made a few for himself. I had sent him the dimensions and the pictures. You could request him to make you a few. Use it only on Windows. Not on fixed mirrors. You can place one cube on each window pane. Try both top right and left hand corners to see which sounds better. If window panes are behind speakers use two hole facing up. If panes in front of speakers use one hole facing up

 

[Hari Iyer]

I understand raghupb

The resonators are practically invisible though

Add a few rosewood cubes on any window panes that you have in your room. You can have it made locally. They cost practically nothing. The cubes are 1 cm with 1 mm holes in them. Google to see how they look. Use Indian rosewood also known as sheesham.

If there is a boom use one or two inverted wine glasses. Lots of guys in Japan use a lot of wine glasses for room treatment. It basically converts bass into higher energy thereby reducing boom. This is not to be confused with what people say glass adds brightness. Here in the inverted technique glass works differently. Use as thin a wine glass as possible.

For diffusion you can add a plant or two behind the speakers if space permits

Raghupb, arj on our forum has the resonators as well the rosewood cubes. You can connect with him to understand how these things work

@ Prem. Thanks for suggestion.

I will like to try the Rosewood resonator method for my window pane behind my listening position. Can i also use simple 1" wooden carrom coins and drill a 2mm hole in it. Please advise how to implement them. Does adding this resonator also helps to tackle boom. My room is quite small around 180 sq.ft and need to reduce the boom a bit. Opening the window pane to reduce boom is not a option due to ambient noise from the road.

For the inverted wine glass suggestion, do the surface have to be concave to achieve this. How does the bass gets trapped in this format? Will require some more ideas. Thanks.