Thanks Curt!
I will check these graphs this week.
I find them hard to read, and I must admit I can't tell if a graph is good or not...

And how can we work on this RT60? By treating the room?
And when somebody announce one figure for the RT60, which figure is it?

Thanks!

Whenever I access this URL with Opera on my Android smartphone I am getting a popup message "your cart e-mail sent successfully" for maybe less than 0.5s.

Wondering what these guys are doing in terms of scripting when people access content on their server ...

yes ;-)

Oh Ramses...Indeed!

Never take a Smart Phone into the Bathroom!    If you do, and remain there for more than Five Minutes....Google Location Services will ensure that you are bombarded with every Laxative, Toilet Paper, etc advert they can send to you.

All in the name of "Improving your Internet Experience"    Intrusive BS imo...

_uck Google.

Hi all,

James Lindenschmidt here. I'm a designer/audiogeek for GIK Acoustics. I'm here to comment specifically on this thread, as a result of Curt's invitation. I can't say I'm an RME user but I've always liked & admired RME products, in part because they are one of the few audio manufacturers to fully support Linux. ;-)

Apologies if what I write here has already been discussed (I haven't had time to read this entire thread) but my comments about how I use RT60 in small rooms as an acoustic designer might also be useful for others, so I'm posting at his invitation.

Regarding RT60, for small rooms I don't spend much time looking at or thinking about RT60. For me that's more of a larger room phenomenon, where we calculate how much absorption is required (in surface area) to reduce RT60 to desired levels in big rooms like auditoriums or basketball courts.

For test data in small rooms, I spend way more time looking at waterfall graphs and impulse response (I wrote an article on my blog about impulse response that might be useful). That tells me tons more that I need to know for a small room. As an example, I recently finished building/treating my own room (I use it for both listening and mixing/producing), and I had to go look at my test data to see what my RT60 was..... I couldn't have told you! I just don't care that much about it, and to the extent that I do care, I'm more concerned that RT60 is consistent across the frequency spectrum than have the average RT60 be at some arbitrary number.

The biggest difficulty I've seen with RT60 is that people are so afraid to have a room that's "too dead" that they won't put enough treatment in (or perhaps more accurately, enough of the right kinds of treatment in) to get a good-sounding room. For instance, the average RT60 for my room above 100Hz is about 125ms, which most people concerned with RT60 will say is far too short. I would invite people who say so to come listen, my room sounds wonderful, quite natural, and it's not like being in an anechoic chamber at all. Of course my room is VERY small (about 10x12).....

So again, yes, for test data in small rooms I'd much rather have a smooth, consistent waterfall graph, and Impulse response. If these are in place, then in my experience the room will sound wonderful no matter what its RT60.

Thanks!

Thanks very much indeed. So now the challenge is to produce and interpret these waterfall and impulse plots, so we can contemplate how to improve the in room response above the Schroeder frequency. By the way, what do you call a small room size?

For sure there is some debate over what constitutes a small room. Certainly anything under 2500 cubic feet of volume is a small room. I'd argue it's even larger, at least in terms of the utility of RT60 times and calculations as determinant of sonic performance. As a real world comparison, I'd say anything smaller than a basketball court is probably more usefully thought of as a small room for this stuff.

As far as testing, I use Room EQ Wizard which is donationware, crossplatform software. It works very very well. GIK has a tutorial video on the basics of usage here. There are links above to articles on the GIK site (the Impulse/ETC article written by me) for help interpreting it. I'm also happy to look at anyone's data if they need help understanding what they are looking at and formulating a good acoustic treatment strategy. Best to contact me offlist for this, preferably by emailing my GIK account (James.L =at= GIKacoustics.com).

Hi All,

I really goofed when I blurted out RT60 while really having the Waterfall Graph in my Mind (or what's left of it)   Of course RT60 data can be found in the Waterfall, but it's only a single slice of the Big Picture.

The Science, and Research involved truly suggests that a "Uniform Decay" is most desirable in our world as James has noted.  There IS NO Magic "Target Number"  in our little Rooms.  The Scientific Models are based on the dimensions/construction of Performance Venues...not Glorified Bedrooms. 

My Take Away:   A reasonably uniform FR.   A reasonably uniform Decay...then walk away from it.  If you like what you hear?  You're Golden!! 

Curt

Willem,

Post Up your Graph, so we can have a look, and Speculate Wildly amongst the Group.

Regards,

Curt

Alex (Noob),

Thanks for the Graph.   You'll think I'm absolutely CRAZY, but in this Band-Limited, and seemingly Un-Smoothed Test, I don't see any major "Stand-Outs"  (ie: Decay Times best measured on a Calendar, etc) 

Unless we're evaluating Speaker Cabinet, or Driver Resonances, I think we at Home are better served by running the Sweep Full Range, and PLEASE use Smoothing!!  I know....I know that some feel we're "obscuring detail", but who needs detail if we're not actually going to fix it?   If we can just put the Data into a Context closer to how we hear it (I like 1/3 Oct) ...We also make the Graph a bit easier to interpret, plus we have the added benefit of a Clearer View of the BIG (Overall) Picture.

Curt

PS:  I warned you all in advance. Room Data can be the Gateway to Insanity. 

PPS:  I don't know if it's advancing Age,.or just Plain Laziness that disuades me from fixating on Minutae.  Simply show me the Big Picture.   The Little things are just that. "Little".   Don't lose Sleep over a Pimple at 11,259hz or the like.   Just assume that it "adds a bit of Air"      

It's all Good Fun Folks!   So go enjoy your Music! 

Be Careful though.  Don't be like Rick (RPGroman) who aggravated a Sore Shoulder while moving Big, Heavy Speakers)

Can I ask.

When running REW through the RME, which filter is best applied? I personally feel that SDSharp should be used as it maintains the highs for a longer period.
Would this be correct?

Mike.

1/3 smoothing, full range.

And just to precise (as I have posted other's graphs): these are my datas, not Willem's

1/3 smoothing really helps, see the raw picture above.

Thanks ramses.

Noob, indeed a Very Encouraging bit of Data!    To maybe add a bit of specificity to my earlier comment about Corner Trapping, consider that Corners are Acoustic Convergence Points in our Rooms.  ALL ROOM MODES (H/W/L) are at Maximum Intensity in Corners.   This is WHY our Parents made us Stand in the Corner when we misbehaved as Children.

If it's possible for You to address this, it is my opinion that it would be beneficial.   Feel free to perhaps reach out to James for a more Scientific assesment. 

Best to You!!

Curt

Alex!

Your Listening enjoyment is all that matters.  If YOU are happy, then we are all happy with You.   That's what the RME Forum is all about.   Good Job!!

Curt

I remember a rehearsal of different speakers in a HiFi shop. They positioned the speakers not following the symmetry of the room.
Using this positioning of speakers the Dr Gauder Berlina RC 3 sounded phantastic presenting a room/stage that was unbelievable deep.
I am wondering whether this special positioning against room symmetry gives certain advantages because it seems to me that you might avoid a lot of 90° reflections in corners by that.

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Any experiences in that regards ?

Hi,

Please find Willem's results this time

Thanks Alexandre for posting this graph. I am not sure what to make of it other than that the issues seem to be concentrated in the bass area, with the 25 Hz as the biggest offender. As I think I wrote before, this may well not be a room mode problem, but resonating sliding doors. The room has a semi open plan design, with large and heavy (each about 2.5 x 2.5 meter) sliding doors opening to my wife's study at one side and to the dining room at the other end. When I play sweeps I hear them resonate at some low frequencies. So I gues what I should do is play sweeps/test tones with known frequencies, so I can see if the doors' resonance is indeed at 25 Hz. Is there such a facility in REW?

Here I go again...

Willem, as I sit here (now at Home!) and Pontificate on matters...  I can't bring myself to cast any doubt on your Door Resonance theory.    Maybe have Frau Jongman place her hands firmly on the Door while you repeat the Sweep to see if that dampening effect is reflected in the data.  Else...Room Gain effects are high on my list of Suspects.

Download a test tone.  Use that with the RTA function in REW. 

BE WARNED...Playing Pure Tones at high levels can be damaging to equipment!!  It's not our plan to break your gear.   Proceed only with great caution!!

Thanks. Yes I know some caution is required.

Indeed, or the floorheating pump.  It may be long search.