Get a mic that is calibrated, e.g. Cross·Spectrum - Microphone Measurement Services
Other system requirements are listed here: Getting Started with REW
Not necessarily, since room boundary reflections and the resulting comb filtering will still be there. Boundary reflections are not the same as room modes.
Here's my room with two subs, equalized with Audyssey MultEQ XT32 (left + sub, 8 locations as far as 60cm apart, red = main listening position):
Question:
The measurement points are 8 locations you say. Are they up to 30 cm away from the main position? And in the horizontal plane only?
Wait, didn't someone tell me just lately that dipoles ALWAYS and in EVERY room produce a smoother frequency response when compared to monopoles? Did hell freeze over?
Horizontal plane only. Here's a detailed description:
Minimizing seat-to-seat variance with two subwoofers
markus, its the last time i reply to your posts. Everything i wrote is my SUBJECTIVE opinion. I mean, who are you? Sheldon Cooper? (jk) I am not here to PROVE anything, and i understand and acknowledge the sources of error that are possible in my assumption vis a vis amplitude resolution. I dont wish to prove anything. Mandrake is correct, downsampling isnt ideal either. In an improved test, i should dub 2 independant wavs, on 2 synched recording platforms. I have neither the facility nor desire to take DBT. I am just a man, and make no bones about it, i neither claim to be more. Im an amateur, and do not promote myself as an audio authority. I could easily be proved incorrect in my evaluation, and i would welcome it. Neither do i have commercial interests, tho it seems that im alone in that recently. But from my testing experience in different fields i have learned that one begins by taking as much data as viable, then filtering to resolve ENOUGH data. That is why i would use 192 24bit for mastering.
I know what i experience, whether its flawed is immaterial. 192k 24bit sounds better to me, for whatever reason, the cause isnt important to me. I endeavour to respect others opinion, please do the same. Im fed up of posting and receiving a tirade of flaming, from others who cannot accept my words for what they are; personal opinion. Seems everyone is an expert, or at least their ego says so. Good luck. Maybe theres a forum where opinion is openly discussed, without a demand for double blind tests. Im off to find it.
I know what i experience, whether its flawed is immaterial. 192k 24bit sounds better to me, for whatever reason, the cause isnt important to me. I endeavour to respect others opinion, please do the same. Im fed up of posting and receiving a tirade of flaming, from others who cannot accept my words for what they are; personal opinion. Seems everyone is an expert, or at least their ego says so. Good luck. Maybe theres a forum where opinion is openly discussed, without a demand for double blind tests. Im off to find it.
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mondogenerator,
Sorry if you feel offended by my posts. I was just trying to discuss the idea of being able to make an objective assessment the way you perfomed the listening test. Nothing personal.
Sorry if you feel offended by my posts. I was just trying to discuss the idea of being able to make an objective assessment the way you perfomed the listening test. Nothing personal.
simon: i use cooledit pro/audition. Dont recall settings but i was aware of downsampling loss. There are too many variables for me to prove anything, other than to myself. Theoretically vinyl is better, in my misguided opinion, with almost infinite sample rate. Dust is the enemy! I have burnt a few vinyl using CEPro at max rates, and forever captivated by the results.
Hendrix at woodstock being my fave.
Markus. Im not offended. I deal with others who radiate a nuclear scientist persona, on a daily basis. Like them, your replies seem arrogant, but perhaps i misinterpret them.
Like many here, i would love to be an expert, or have a speaker shop, and make some real cash. Sadly im an imdustrial worker with aspirations above my station in life. I can spell, and my grammar is good, so naturally im not a mathematical genius, but i manage 😀
Hendrix at woodstock being my fave.
Markus. Im not offended. I deal with others who radiate a nuclear scientist persona, on a daily basis. Like them, your replies seem arrogant, but perhaps i misinterpret them.
Like many here, i would love to be an expert, or have a speaker shop, and make some real cash. Sadly im an imdustrial worker with aspirations above my station in life. I can spell, and my grammar is good, so naturally im not a mathematical genius, but i manage 😀
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what? and you want 1hz precision measurements from Stig Erik? What are you smoking if I may ask? 😎
besides, your mesurements certainly look good, but not impressive. You probably base yourself on Devantier/Welti, then you should know you can theoretically reach even better response with 4 subs instead of two.. I am wondering how such a setup would work with big dipoles, I haven't seen any studies on that. Don't ask me to try or prove, I don't have the $$ for that, sorry!
And what are you smoking? 🙂
Welti looked only at symmetrical locations. My subs aren't placed symmetrically.
Ah.. I'm a cool dude by nature, no need for glue! 🙄
what I meant is your "good" area is rather small, compared to the 2x2m square the former mentioned scientist are using.
what I meant is your "good" area is rather small, compared to the 2x2m square the former mentioned scientist are using.
What graphs are you looking at? From Toole, "Sound reproduction" (data from Welt/Devantier):
An externally hosted image should be here but it was not working when we last tested it.
nope, this one:
http://www.aes.org/tmpFiles/elib/20120816/13680.pdf
they actually used an average of 16 positions off a 3x3m grid.
and this one, the 2x2m grid:
http://www.harman.com/EN-US/OurCompany/Technologyleadership/Documents/White%20Papers/multsubs.pdf
but the Toole data must also mention an averaged 2x2 grid somwhere..
http://www.aes.org/tmpFiles/elib/20120816/13680.pdf
they actually used an average of 16 positions off a 3x3m grid.
and this one, the 2x2m grid:
http://www.harman.com/EN-US/OurCompany/Technologyleadership/Documents/White%20Papers/multsubs.pdf
but the Toole data must also mention an averaged 2x2 grid somwhere..
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Yes, and they do.
Dipoles are less affected by boundary reflections as well as room modes, because they are more or less "dead" at 90 degrees off-axis in both the vertical and horizontal plane.
Good, we're looking at the same graphs which makes me wonder what you're actually trying to tell me 😕
StigErik ... I'm trying to understand why you feel that boundary reflections are less affected w/dipole ... ? Aside from the polar pattern, you still have a much stronger rearward projection than w/monopole ... no? My listening, in an untreated room @ elevated SPL's, doesn't follow along with this.
... unless the "every room" has acoustic treatment?
... unless the "every room" has acoustic treatment?
just saying that your mesurements were done over a rather limited area, unless I misunderstood something in your setup, a 60cm listening line is nothing extraordinary to be honest, that's almost the size of my listening chair.
Pause before pulling the trigger, I am not criticizing anything here, but if your scope is to prove something, I think you may only be half way..
Not really. A small monopole subwoofer will be omnidirectional at low frequencies, and radiate the same amount of energy in all directions.
The area in my measurements is 1m x 30cm. That should work even for very large heads and ears 🙂
As I said before, Welti looked only at symmetrical locations in a rectangular room. My room isn't rectangular and I only use two subs, nonetheless the measured response is better than anything Welti shows. So it's obviously worthwhile looking into more locations than just symmetrical ones. And, 4 subs is not necessarily better than 2 subs. It also depends on how good the actual locations are in terms of equalizability.