Room Treatment Advice

[sound_cycle]

Talking about room treatment and the bare basics.
If you dont have the possibility of setting up a dedicated room with the foam treatment etc... for whatever reasons.

Will it make any difference in the acoustics if you go with Wall paper vs regular paints on the walls ?

-Fillmore

Hi

Sidvee has already answered the paints/ papers as treatment question you ask.

I **think** what you are wondering about is unobtrusive/ invisible/ WAF independent room treatment and that the answer you seek lies in digital room correction.

I understand that DRC needs the problem of early reflections addressed before it can start working its magic. So does that brings us back to square 1 ?

Not really because the broadband panels would have to be unreasonably thick at lower frequencies [a quarter of the wavelength you are trying to kill] and DRC becomes very important there.

That is a long slippery and steep slope that I might have to climb some day .... and atm have not enough understanding/ shekels to spare

ciao
gr

ciao
gr

 

[soulforged]

I **think** what you are wondering about is unobtrusive/ invisible/ WAF independent room treatment and that the answer you seek lies in digital room correction.

...or in a good pair of headphones

 

[sound_cycle]

That is a long slippery and steep slope that I might have to climb some day .... and atm have not enough understanding/ shekels to spare

So started to climb that mountain. Got the mike. Made a temporary stand (far from ideal) and got a first few measurements using the REW plugin and this default method. Room EQ. As I expected the graphs were different for the two channels (unequal distances from side walls).

It has definitely knocked off the boominess. The cellos in Claire Martin (The man who sold the world) or the organ in Te Deum sound nicer now, Sade (Is it a crime) or Steely Dan (Peg) too. GnR (Paradise City) sounds like I am in a bunker across the city (to be sure I did not have a ticket to the arena earlier).

The son does not like it. He says you have made the Dalis into something we used to have earlier, but that's okay, I don't agree with him.

Next step ? I want to try Dirac, and ofc BBS a stand with a boom, read up, try out speaker re-arrangement and if I work up the courage rearrange the sound treatment I had put up i.e generally frustrate myself :lol:

ciao
gr

 

[sound_cycle]

Used son's camera tripod and some bungee cords to get the microphone correctly positioned. So did not need to beg/ borrow/ steal or rent a mic stand with a boom.

Once I had this figured out could not wait to download DiracLive and set it up (later in the evening is nice because various irritating sound sources are asleep).

Getting it installed and running was very easy.

Initial impression is of a subtle and very nice change. Interesting the imaging is nicer. So far have heard only te deum and the ledr cockroaches while people use the liv(sten)ing room for its legitimate purposes (which sadly seems to involve standing between me and a speaker for extended lengths of time)

ciao
gr

 

[mpw]

sound_cycle,

please do put up some pictures..

regards

 

[sound_cycle]

sound_cycle,

please do put up some pictures..

regards

Hope that flickr link works

ciao
gr

edit:added picasa links

 

[sound_cycle]

Hi,

The first set of measurements I made were probably not optimally spaced, ofc I implemented the RTFM step after having jumped into the deep end.

I posted some of the stuff I learnt on the Dirac review thread last night.

What did I get for my trouble (let me qualify, that "trouble" involved reading a slim manual, reading the instructions on side bars in the calibration software and spreading the measuring points over a wider area).

I think a much nicer image, fine detail, subtle stuff. the big thing is that one note bass has given way to nicer more tuneful stuff. But that small gain is rather satisfying.

Overall I think I like it, the wife does too. I have another ten days on the trial to figure out but I think I have the Dirac setup basics worked out.

After this I can only laugh at my wide eyed innocence a year back when I plonked the speakers in the room and marveled at the bass and detail. There really is no comparison between then and now, or for that matter from when FM Kaushik dropped by and now.

I *know* that what I have can be improved on by someone with more knowledge and understanding but I think I won't embarass myself, badly if the listeningpolice were to drop by unannounced.

Next steps ? See if I can fine tune the filters better, improve the placement of my broadband absorbers, and though there is no way, get rid of that TV in between the speakers. And for sure substantiate the improvements (if there are any) with measurements. Hopefully accumulate some Vit M for the licensed version - I am that far gone . There are other DRC sw to try out as well.

ciao
gr

 

[mpw]

the word - know - is pretty powerful and fulfilling at the same time.

congratulations !

some day i hope to walk down this road myself.

regards

 

[sound_cycle]

Hi,

Made another set of measurements, this time using a scale and a piece of string to place the mic. that bit more precisely than merely eyeballing it.

Also minorly tweaked the position of the rockwool bits at the rhs first reflection point.

The result, to me, is stunning.

We had lunch at Moti Mahal today, and as the paneer tiranga was served, that old favorite Rahman's Vande Mataram was playing. The wife and I were then telling the son, the experience of hearing/viewing that track at Prasad's Imax (before the screening of Everest, about 12 years back). Hairs at back of neck tingling type and I went back the next day, to listen to the track and the sound once again.

We got back home and one of the first tracks we played was this one.

Wow ! A track I have heard so many times sounding so much nicer. The son agrees the filter OFF sound (with everything else left unchanged) is now undesirable and not nice.

I am completely sold on the idea that I need, absolutely need to have Dirac Live.

I only have a week left on the trial, it is going to be an impatient time till i get the license, it is expensive. But I will.

I would have liked to try out the Dirac claim that their system will produce beneficial results in the absence of any treatment, but mine is mostly screwed into place.

I have no hesitation, in saying that if you have not tried this tweak, you should.

I guess I have got about where I wanted to be, when I set out about setting up the first proper rig, and can now lick wallet wounds and listen to the music

ciao
gr

 

[saikatbiswas82]

@sound_cycle... Congratulations on your effort in DIY and thanks for the detailed writeup.

I might be going the DIY way for my HT room treatment in next few months.

My question is.... Will it be OK if I use 48 density Glasswool sheets for the absorbers and base traps?

Due to budget constraints, it won't be possible for me to get rockwool.

 

[sound_cycle]

Hi,

If I were doing it again I would use lower density than I have see here for explanation..

The other thing I would do is have the tailoring / covers stitched before hand, and all the measuring / positioning done before bolting things into place.

I have not noticed any leak of material/ scratchiness from the material I used. I *guess* I would have got by with glasswool too. (there is a long thread on possible health hazards etc on hfv).

There are several nice, informative write ups on room treatment on hfv which got me started, so there is lots of info here.

Do give it a shot, IMHO really worth it.

ciao
gr

 

[sound_cycle]

Hi

Made some minor changes to the "decor" (that's what I am calling it). Got heavier drapes, rearranged the BB absorber at the first reflection spot. The results are measurably different. (I know, but kya karen I have an absorber, I will make a diffuser some day and try it out)

Interesting thought, that curtain drawn or closed can result in a *measurably* different sound. I can create filters that make the sound brighter or the bass tighter or shrink the sound stage. In a replicable manner, for my room.

I think I have it more or less dialled in now and i like the sound with Dirac Live and the filters I created.

Hate it without.

Have till Sat evening I think on the trial.

And then what ?

You see the irony ? Here is the only audio bit that I have auditioned extensively, in my room, and I am having doubts on whether I want it and is it good even though I like it. And I know that this is not some subjective imaginary thing, and have the graphs and things too look at, hmmm.

I think I have to get it, even though there will be no shopper's rush and triumphant pics or shiny objects to look at

ciao
gr

 

[sidvee]

. And I know that this is not some subjective imaginary thing, hmmm.

Great to hear that sound_cycle. IMO room acoustic treatment whether by physical acoustic products or via DSP is one of the most important component for good sound. A fact sadly overlooked by many.
Cheers,
Sid

 

[sound_cycle]

I think I have it more or less dialled in now and i like the sound with Dirac Live and the filters I created.

Aargh! But have I

Computer Audiophile - Acourate Digital Room and Loudspeaker Correction Software Walkthrough

Set up to take measurements:

The measurement microphone is set up in the listening position. I have been using DRC software for 2 years and measuring speaker systems/acoustic spaces spanning 30 years.

• Establish a Reflection Free Zone (RFZ) in the listening area as best as possible.
  Did not/ cannot use calibrated acoustic string
  No idea about this. From a technical measurement perspective, the rule of thumb is, with an ETC window from 0 to 50 milliseconds, all reflections (amplitude spikes) are -20 dB or lower from the peak
  
• For acoustic measurements, move any chairs, tables, sofas, etc. out of the way between the speakers and the listening position.
  Did not move sofa out of the way, does it matter it is below lowest mic ht ?
• Set the height of the measurement mic to be the same height as ones ears (while sitting in the listening position) and ideally that would be the same height as the speakers tweeters.
• If measuring a stereo system, point the microphone towards the speakers, down the centerline. If measuring a surround system, point the measurement mic straight up. Whichever position is chosen, be sure to use the corresponding calibration file. There should be a calibration file for on axis response and one for 90 degree diffuse response.
  Finally a tickmark !
• Whether using a tape measure or laser distant measurer, it pays sonic dividends to line everything up to be as symmetrical in the room as possible and to as tight of a tolerance one can achieve. Hint: a 20 kHz frequency has a wavelength of 0.678 inches. I recommend marking the mic position once set up so it is easy to place the mic in the same spot the next time around.
  Can be improved

In short fail and not the passed with distinction I had awarded myself .

To be sure the calibrated string is not an issue of laziness or lack of diligence, I just do not have the space.

Will retry in the evening, after reading this thread if I can conscript labor for holding string, moving sofa etc. Doubtful though since these days the labor is very opinionated and forceful, and has taken to passing smart alec remarks about my audio ideas ie generally uncooperative.

edit: added link on etc measurement

ciao
gr

 

[sound_cycle]

So after a lot of fiddling and figuring, got the speakers into the perfectly position.

The process was long and complicated. To make matters very funny, the measured and positioned location is only a few mm off from what the consscripted help and I had worked out by ear, a while ago. His ear and my elbow and knee grease to be precise, but then at 14 his hearing is much better than mine, so that is okay.

The graph shows the ghostly hills that existed and marched forward booming into my hearing.

The pinkish red hill range is post Dirac. You will see that most of the ridges have been pushed back and the peaks have been beaten down

I have a missing bit about 116 Hz. Working on getting that null figured out.

So there you are ladies and gentleman, Dirac works, and here is the proof that it does.

ciao
gr

 

[mpw]

wonderful ! amazing !

thanks for sharing this pic...

regards

 

[sdurani]

The graph shows the ghostly hills that existed and marched forward booming into my hearing.

The pinkish red hill range is post Dirac. You will see that most of the ridges have been pushed back and the peaks have been beaten down

Can you re-post the graph with the before/after measurements normalized (peaks on both measurements at the same height)?

 

[sound_cycle]

Can you re-post the graph with the before/after measurements normalized (peaks on both measurements at the same height)?

Hi,

Trying to figure out how to get that done.

ciao
gr

 

[sound_cycle]

Hi

Still no luck.

to confuse me further there is this post by the author of REW which seems to suggest that it cannot be done in REW

ciao
gr

 

[sdurani]

there is this post by the author of REW which seems to suggest that it cannot be done in REW

In that case, can you re-measure the "after" measurement 5-6dB louder (just turn up your pre-amp) so that the tallest peak in the before measurement matches the tallest peak in the after measurement? That will more accurately show whether Dirac's correction is mostly about lowering the overall level or actually fixing peaks & decay times.