Post by Hexspa on Oct 22, 2017 16:28:40 GMT
Ok, I'm on my off time but here's a cool link:
Listening conditions for the assessment
of sound programme material:
monophonic and two–channel stereophonic
tech.ebu.ch/docs/tech/tech3276.pdf
Pretty much I'll just copypasta my notes. These are their standards:
(1m=3.28')
2m<b<4m speaker triangle (speakers between 6.56 and 13.12' apart) BUT your head should be 0.9 whatever distance your speakers are from each other (i.e. don't sit in a perfect triangle). [Apparently, this is echoed somewhat by Jim Smith (Get Better Sound) with his "83% rule" forum.audiogon.com/discussions/how-far-apart-do-you-position-your-speakers In Rod Gervais' book Build it Like the Pros he suggests triangulating speakers 16" behind your arqen.com/acoustics-101/room-setup-speaker-placement/head . My speakers are about 55" apart and 16" is 30% of that distance which is way out. The takeaway here though is not to point tweeters directly at your ears.]
1m speaker distance from boundary (not soffit)
1.5m listener distance from boundary (4.92')
30m square floor surface (322.92 ft2)
300m max vol (10594.4 ft3) - you heard it guys don't build rooms bigger than this!
Don't put anything in front of speakers
"Golden Ratio" formula:
1.1w/h ≤ l/h ≤ 4.5w/h – 4
l < 3h
w <3h
where:
l = length (larger dimension of floor plan, irrespective of orientation)
w = width (shorter dimension of floor plan, irrespective of orientation)
h = height.
In addition, ratios of l, w and h which are within + 5% of integer values should also be avoided.
Symmetry is important
RFZ too
Dampen rattles
Background noise is measured on a curve - the higher the frequency, the quieter it should be - not "perceptively impulsive, cyclical or tonal in nature." Check section 2.6.
Speakers should be flat +- 4dB from 40Hz to 16kHz direct incidence.
Funnily, I went there to understand why they require such a short RT60 and I didn't get my answer. Maybe you can ELI5. I know they want this: "0.2 < Tm < 0.4 s" where "Tm is the average of the measured reverberation times in the 1/3–octave bands from 200 Hz to 4 kHz." Larger rooms can have longer decay but you have to be a math whiz to know how much. In all cases, low frequencies can decay slightly longer but not by much. Frequencies above 4kHz can decay shorter but by even less.
Early reflections < 15ms and must be -10dB between 1kHz and 8kHz.
Frequency response should be no greater than +3dB throughout and -3dB below 2kHz and -1dB/oct thereafter above 2kHz. Each speaker should meet this tolerance separately at LP.
Corrective EQ ok below 300Hz.
Here's an example of the ratio formula with working numbers:
1.1x15' / 8 < 23'/8' < 4.5x 15'/8' - 4
2.06 < 2.88 < 4.44
Where 8=h, 15=w and 23=l
---
Basically, we're all you-know-what. That whole "-20dB within 150ms" decay target is garbage according to the EBU. They want to double that, on average.
If anyone needs a studio it'll be in my dumpster later this afternoon lol. jk
Thanks.
Listening conditions for the assessment
of sound programme material:
monophonic and two–channel stereophonic
tech.ebu.ch/docs/tech/tech3276.pdf
Pretty much I'll just copypasta my notes. These are their standards:
(1m=3.28')
2m<b<4m speaker triangle (speakers between 6.56 and 13.12' apart) BUT your head should be 0.9 whatever distance your speakers are from each other (i.e. don't sit in a perfect triangle). [Apparently, this is echoed somewhat by Jim Smith (Get Better Sound) with his "83% rule" forum.audiogon.com/discussions/how-far-apart-do-you-position-your-speakers In Rod Gervais' book Build it Like the Pros he suggests triangulating speakers 16" behind your arqen.com/acoustics-101/room-setup-speaker-placement/head . My speakers are about 55" apart and 16" is 30% of that distance which is way out. The takeaway here though is not to point tweeters directly at your ears.]
1m speaker distance from boundary (not soffit)
1.5m listener distance from boundary (4.92')
30m square floor surface (322.92 ft2)
300m max vol (10594.4 ft3) - you heard it guys don't build rooms bigger than this!
Don't put anything in front of speakers
"Golden Ratio" formula:
1.1w/h ≤ l/h ≤ 4.5w/h – 4
l < 3h
w <3h
where:
l = length (larger dimension of floor plan, irrespective of orientation)
w = width (shorter dimension of floor plan, irrespective of orientation)
h = height.
In addition, ratios of l, w and h which are within + 5% of integer values should also be avoided.
Symmetry is important
RFZ too
Dampen rattles
Background noise is measured on a curve - the higher the frequency, the quieter it should be - not "perceptively impulsive, cyclical or tonal in nature." Check section 2.6.
Speakers should be flat +- 4dB from 40Hz to 16kHz direct incidence.
Funnily, I went there to understand why they require such a short RT60 and I didn't get my answer. Maybe you can ELI5. I know they want this: "0.2 < Tm < 0.4 s" where "Tm is the average of the measured reverberation times in the 1/3–octave bands from 200 Hz to 4 kHz." Larger rooms can have longer decay but you have to be a math whiz to know how much. In all cases, low frequencies can decay slightly longer but not by much. Frequencies above 4kHz can decay shorter but by even less.
Early reflections < 15ms and must be -10dB between 1kHz and 8kHz.
Frequency response should be no greater than +3dB throughout and -3dB below 2kHz and -1dB/oct thereafter above 2kHz. Each speaker should meet this tolerance separately at LP.
Corrective EQ ok below 300Hz.
Here's an example of the ratio formula with working numbers:
1.1x15' / 8 < 23'/8' < 4.5x 15'/8' - 4
2.06 < 2.88 < 4.44
Where 8=h, 15=w and 23=l
---
Basically, we're all you-know-what. That whole "-20dB within 150ms" decay target is garbage according to the EBU. They want to double that, on average.
If anyone needs a studio it'll be in my dumpster later this afternoon lol. jk
Thanks.
YES pasim. In an anechoic chamber too. 