apl
Stand Up Comity
COOLCAT said:
Is that supposed to be a system that tries to creat a flat room? That's very difficult. You can maybe make on tiny area in a room kinda flat, but move your head over 6" and it'll be down the toilet again. I think Ethan's article explains that.
CoolCat
Well-known member
yes, i think this is a JBL version of the Radio Shack SPL meter?
i would think its a better unit. at least $44 better.
wondered if anybody had bought it yet.
your 6" remark, i ve read this by others too...
How do studios quantify sound-improvements?
thats the root question.
its frustrating somewhat with rooms. In comparison, a "Standard" has been achieved with guitar string tuners, they work and everyone agrees!
can't we tune a room the same way? its freq and DB.
this physics of sound gets very subjective (frustrating).
SCENARIO:
so some guy does your studio, charges you $15,000 and tells you
"thats it! its FLAT now!! see you later!! will that be credit or check??"
and you, the studio owner replys "hmm...it sounds good, i guess? isn't much different than i had it?? hmmm... i think i hear a difference??hmmm..ok,
$15,000..ok."
but if one moves their head 6" its all fhkd anyway? or if someone moves in a rack cabinet, or hangs a guitar on the wall..is it $15,000 down the toilet?
again How do quantify its flat? or if an improvement was even made?
some dude going "hey thats sounds better man..(sucks in some more smoke...that'll be like $50 for the room tune man...cool)...
so yeah APL,
i get confused...seems there isn't a very clear answer.
No Standard to Tune a room.... or even check a room cheaply?
i had another SPL thread asking for plots of HR studios and no one even responded, which means most didn't want to reply or
don't even attempt to measure the room...i believe the latter.
yet when buying monitors and mic's its all about "flat", clear" transparent".... specs...but no one can quantify it.
SCENARIO #2:
so if i play a 1Khz and 200hz and a 8khz signal from a CD thru my SIAB into and out of my Monitors... at my mixing position will the meter read 85db, 85db,85db... that may be as good as it gets for HR...for $99.
i would think its a better unit. at least $44 better.
wondered if anybody had bought it yet.
your 6" remark, i ve read this by others too...
How do studios quantify sound-improvements?
thats the root question.
its frustrating somewhat with rooms. In comparison, a "Standard" has been achieved with guitar string tuners, they work and everyone agrees!
can't we tune a room the same way? its freq and DB.
this physics of sound gets very subjective (frustrating).
SCENARIO:
so some guy does your studio, charges you $15,000 and tells you
"thats it! its FLAT now!! see you later!! will that be credit or check??"
and you, the studio owner replys "hmm...it sounds good, i guess? isn't much different than i had it?? hmmm... i think i hear a difference??hmmm..ok,
$15,000..ok."
but if one moves their head 6" its all fhkd anyway? or if someone moves in a rack cabinet, or hangs a guitar on the wall..is it $15,000 down the toilet?
again How do quantify its flat? or if an improvement was even made?
some dude going "hey thats sounds better man..(sucks in some more smoke...that'll be like $50 for the room tune man...cool)...
so yeah APL,
i get confused...seems there isn't a very clear answer.
No Standard to Tune a room.... or even check a room cheaply?
i had another SPL thread asking for plots of HR studios and no one even responded, which means most didn't want to reply or
don't even attempt to measure the room...i believe the latter.
yet when buying monitors and mic's its all about "flat", clear" transparent".... specs...but no one can quantify it.
SCENARIO #2:
so if i play a 1Khz and 200hz and a 8khz signal from a CD thru my SIAB into and out of my Monitors... at my mixing position will the meter read 85db, 85db,85db... that may be as good as it gets for HR...for $99.
B
bpape
Acoustic Designer - GIK
Relating to scenario #1....
Anybody that would tell you "OK. The room is flat." Should have his head 'flattened.' You'll never get ANY room perfectly flat. You can get it within a reasonable range and at a few positions.
Unfortunately, it's just natures laws that keep getting in the way. The ONLY way you're going to get every position in the room to sound the same (or even close) is to have everyone wear headphones. Otherwise the sound in the room WILL change.
Fortunately, the real goal (lost by many people) is only to make it sound good and as even as possible where people actually sit and listen. Anything else and anyWHERE else is irrelevant. IMO, the BEST thing one can do to assure this is to design the room and it's seating so you're not immediately shooting yourself in the foot acoustically - trying to fix a seat dead center of the room or right up against a wall.
IMO, this is the biggest thing you can do to improve the listening experience - and it's free!
If you start out with 'tunable' seating positions, the goal of having a good room certainly exists. If you insist on starting with too much seating for a space, putting things in corners, up against walls, etc., then you're just asking for an exercise in frustration.
Anybody that would tell you "OK. The room is flat." Should have his head 'flattened.' You'll never get ANY room perfectly flat. You can get it within a reasonable range and at a few positions.
Unfortunately, it's just natures laws that keep getting in the way. The ONLY way you're going to get every position in the room to sound the same (or even close) is to have everyone wear headphones. Otherwise the sound in the room WILL change.
Fortunately, the real goal (lost by many people) is only to make it sound good and as even as possible where people actually sit and listen. Anything else and anyWHERE else is irrelevant. IMO, the BEST thing one can do to assure this is to design the room and it's seating so you're not immediately shooting yourself in the foot acoustically - trying to fix a seat dead center of the room or right up against a wall.
IMO, this is the biggest thing you can do to improve the listening experience - and it's free!
If you start out with 'tunable' seating positions, the goal of having a good room certainly exists. If you insist on starting with too much seating for a space, putting things in corners, up against walls, etc., then you're just asking for an exercise in frustration.
Track Rat
Just Your Average Sized Member
Tuning a room with EQ is a losing proposition, which it appears this JBL thing is trying to do. There are lots of things a person can do to calculate room modes within reason and treat acousticly with traps and such and measure their effectivness. Personally I treated my control room acousticly and then just LEARNED my near fields. It works for me.
CoolCat
Well-known member
yeah guys thanks for the sanity check.
seems it always comes down to LEARNING your setup whether its monitors, mics, or whatever.
still it'd be nice to be able to quantify the improvements, from positioning of the traps and foam and monitor placement etc, with a value/meter. i guess they market some of these gadgets at people like myself.
i hear all this "flat" jargon..then i wonder how do they know its flat or improved? or within +/- 3db? because the spec said it is, they don't actually test it out themselves? do you put up 5 traps or 25? 10qty Auralex foam pcs. or 4qty?
if you can't quantify it, other than using ones ears,...thats very,very subjective. reminds me of the days before electronic guitar tuners, the garage band would sit around and tune guitars for 2hrs arguing .."i'm IN TUNE MAN!!"
the other guy "NO YOUR NOT! YOUR OUT and I'M IN TUNE MAN!!"
"Huh uh..no your not..your E is flat man!"
"nu uh, your E string is sharp!!...YOUR OUT OF TUNE, Not ME!!"
the little Electronic Guitar tuners stopped all that sht, for the most part.
Room Response, is it a "fhk it" attitude?
like Joe Meek was quoted "if it sounds good, it is good".
bape, you got exactly what i was going for on that,
only interested in the one mixing position for my HR...
hell i'm confused enough with this one mixing spot, and don't even want to comprhend the brain-fry of doing several rooms, several locations, the corners, what if someone is standing in the room!
its all too much.
this is my second go around with this SPL stuff, and it has alot of "holes in the concept" in the theory to real world. but my ears don't doubt the reduction in the unpleasent DryWall sound, so I like the traps and foam for sure! but when do you know when to stop?
another analogy is cars, when they lift the hood & modify..they have tools that can say.."rep! added 250 rpm!"..or "yep! it really does go 130mph!!"
on sound it seems its like.."rep! added 5 more traps and $200 in Auralex and its flat! well almost flat! rep!"..."i need new monitors probably because mine have a scoop at 400-800hz, these new ones i tried are really flat and have easy 25Khz ability..i mix at 78db!"
so we apply numbers in our communication of sound but without an easy way to quantify them??
...i'm starting to get it, oh yeah its all getting clearer now...
seems it always comes down to LEARNING your setup whether its monitors, mics, or whatever.
still it'd be nice to be able to quantify the improvements, from positioning of the traps and foam and monitor placement etc, with a value/meter. i guess they market some of these gadgets at people like myself.
i hear all this "flat" jargon..then i wonder how do they know its flat or improved? or within +/- 3db? because the spec said it is, they don't actually test it out themselves? do you put up 5 traps or 25? 10qty Auralex foam pcs. or 4qty?
if you can't quantify it, other than using ones ears,...thats very,very subjective. reminds me of the days before electronic guitar tuners, the garage band would sit around and tune guitars for 2hrs arguing .."i'm IN TUNE MAN!!"
the other guy "NO YOUR NOT! YOUR OUT and I'M IN TUNE MAN!!"
"Huh uh..no your not..your E is flat man!"
"nu uh, your E string is sharp!!...YOUR OUT OF TUNE, Not ME!!"
the little Electronic Guitar tuners stopped all that sht, for the most part.
Room Response, is it a "fhk it" attitude?
like Joe Meek was quoted "if it sounds good, it is good".
bape, you got exactly what i was going for on that,
only interested in the one mixing position for my HR...
hell i'm confused enough with this one mixing spot, and don't even want to comprhend the brain-fry of doing several rooms, several locations, the corners, what if someone is standing in the room!
its all too much.this is my second go around with this SPL stuff, and it has alot of "holes in the concept" in the theory to real world. but my ears don't doubt the reduction in the unpleasent DryWall sound, so I like the traps and foam for sure! but when do you know when to stop?
another analogy is cars, when they lift the hood & modify..they have tools that can say.."rep! added 250 rpm!"..or "yep! it really does go 130mph!!"
on sound it seems its like.."rep! added 5 more traps and $200 in Auralex and its flat! well almost flat! rep!"..."i need new monitors probably because mine have a scoop at 400-800hz, these new ones i tried are really flat and have easy 25Khz ability..i mix at 78db!"
so we apply numbers in our communication of sound but without an easy way to quantify them??
...i'm starting to get it, oh yeah its all getting clearer now...
apl
Stand Up Comity
About the only rooms that are flat are hemi-anechoic, anechoic, and reverberant chambers. They are worthless for recording.
CoolCat
Well-known member
i'm not even expecting flat anymore.
but last time i did the Radio Shack SPL, at the mix position, the chart looked pretty Un-Flat. Looked worse than it sounded.
I also took the radioshack meter back for a refund after many saying it wasn't really telling me anything either. (too many variables, not calibrated etc..).
so the JBL SPL meter i thought maybe better. But its probably the same, as its the same concept.
everyone seems to like alot of traps and foam and mopads.
but apparently, most don't use the SPL meters and take readings, is my current understanding, as no one really believes the data due to the "real world" variables are too numerous.
why is it so debatable and treated with such skepticism? i don't fully get it.
i often use meters for voltage, resistance. oscilliscopes, handhelds..
we have meters for Tuning Guitars, Pianos...numerous automotive meters....
no one debates those.
but sound... seems its too complex?
but last time i did the Radio Shack SPL, at the mix position, the chart looked pretty Un-Flat. Looked worse than it sounded.
I also took the radioshack meter back for a refund after many saying it wasn't really telling me anything either. (too many variables, not calibrated etc..).
so the JBL SPL meter i thought maybe better. But its probably the same, as its the same concept.
everyone seems to like alot of traps and foam and mopads.
but apparently, most don't use the SPL meters and take readings, is my current understanding, as no one really believes the data due to the "real world" variables are too numerous.
why is it so debatable and treated with such skepticism? i don't fully get it.
i often use meters for voltage, resistance. oscilliscopes, handhelds..
we have meters for Tuning Guitars, Pianos...numerous automotive meters....
no one debates those.
but sound... seems its too complex?
apl
Stand Up Comity
COOLCAT said:
OK, if you want to really measure a rooms response, you'd get a calibrated source and a calibrated microphone and make 100s of measurements, and those measurements would actually be amplitude vs. frequency. And that set of data would cover the room for that source location.
It's not worth it.
When you tune a guitar you've only got six data points. Tuning a room is literally thousands of data points.
mshilarious
Banned
apl said:
If you allow yourself a reasonable tolerance, it ain't that hard. If you're only interested in before and after, get that Behri measurement mic, a pink noise clip, and some RTA software, and there you go.
I'll post my results as soon as I'm up--monitors will just be getting hooked up next week; I have all the fiberglass (2 boxes of 4", oh yeah) so I'll throw it in the room temporarily just for a test. I need a measurement mic though.
Edit: Ok, solved that last problem--just picked up an Apex 220. I believe that's the identical mic to the Behri ECM8000, but I felt the black finish and lack of Behri logo were worth the extra $5
Hey, this is my first Chinese mic!Stay tuned for room before & afters, sometime next week.
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CoolCat
Well-known member
that'll be great. before and after..even better.
thats the same mic DARNOLD mentioned? maybe i'll spring for one of those damn mics... its tight around here at the moment, but their pretty damn cheap and somethings gotta give, there has to be some "basic" HR test method to help setup a shit-box drywall room. sqeeze every drop out of it as they say.
APL, i'm just looking for a mixing position read, mainly.
it ain't worth it..hehehe, thats funny and may very well be true!
yeah, i like that "Before and After", very simply put..
thats the same mic DARNOLD mentioned? maybe i'll spring for one of those damn mics... its tight around here at the moment, but their pretty damn cheap and somethings gotta give, there has to be some "basic" HR test method to help setup a shit-box drywall room. sqeeze every drop out of it as they say.
APL, i'm just looking for a mixing position read, mainly.
it ain't worth it..hehehe, thats funny and may very well be true!
yeah, i like that "Before and After", very simply put..
mshilarious
Banned
Here's my before graphs
OK, this is in a totally untreated, reflective 17' x 14' room with laminate floors and a 4' opening to a stairwell and hall. The chain is as clean as I can get; probably the biggest variable is the Apex 220 mic which according to its graph for that specific mic (a nice touch for $50), is +-2dB across the range, low in the lows and high in the highs . . .
First graph is close-mic mono monitor + sub, which is a full range system from 30 Hz to 18 kHz, and supposedly flat from about 80 Hz to 12 kHz. Measurements were performed using Wavelab 5 analysis tools, with pink noise @ 85dBSPL at a distance of 3' from the monitors.
Second graph is a room response chart--not too bad, but there are a few obvious dips forming. The room graph was normalized to the close-mic level, and the pink noise source file is plotted against the results in red.
Tomorrow I'll bring in my 6 sheets of 4" rigid fiberglass and see what happens.
OK, this is in a totally untreated, reflective 17' x 14' room with laminate floors and a 4' opening to a stairwell and hall. The chain is as clean as I can get; probably the biggest variable is the Apex 220 mic which according to its graph for that specific mic (a nice touch for $50), is +-2dB across the range, low in the lows and high in the highs . . .
First graph is close-mic mono monitor + sub, which is a full range system from 30 Hz to 18 kHz, and supposedly flat from about 80 Hz to 12 kHz. Measurements were performed using Wavelab 5 analysis tools, with pink noise @ 85dBSPL at a distance of 3' from the monitors.
Second graph is a room response chart--not too bad, but there are a few obvious dips forming. The room graph was normalized to the close-mic level, and the pink noise source file is plotted against the results in red.
Tomorrow I'll bring in my 6 sheets of 4" rigid fiberglass and see what happens.
CoolCat
Well-known member
thats interesting.
i don't get the chart or how it drops off in DB from the low freq to the high freq? this is "pretty good"?
deleted: question, i got your charts now.
Before and After, this is even better, imo.
i don't get the chart or how it drops off in DB from the low freq to the high freq? this is "pretty good"?
deleted: question, i got your charts now.
Before and After, this is even better, imo.
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mshilarious
Banned
Today's chart
OK, no room treatment yet, I had to fix a few problems. I wasn't happy with the low frequency response, so I tested the subwoofer alone, and made a few changes to the crossover to fix that. I also added the second monitor so I've got the full setup now, and recalibrated the level to 85 dB with all three.
So today's chart is just a revision of yesterday. I also tried to make it easier to read. Interesting the close performance is worse, but I'm pretty sure that's from the mic being so close that it doesn't get uniform response near the crossover frequency on the sub. Across the room, the curves look better, but there's still a decent -4 dB drop at 194 Hz, and a 3 dB spike at 258 Hz. I'll see what the fiberglass does tomorrow, weather allowing (it's in outdoor storage).
OK, no room treatment yet, I had to fix a few problems. I wasn't happy with the low frequency response, so I tested the subwoofer alone, and made a few changes to the crossover to fix that. I also added the second monitor so I've got the full setup now, and recalibrated the level to 85 dB with all three.
So today's chart is just a revision of yesterday. I also tried to make it easier to read. Interesting the close performance is worse, but I'm pretty sure that's from the mic being so close that it doesn't get uniform response near the crossover frequency on the sub. Across the room, the curves look better, but there's still a decent -4 dB drop at 194 Hz, and a 3 dB spike at 258 Hz. I'll see what the fiberglass does tomorrow, weather allowing (it's in outdoor storage).
CoolCat
Well-known member
excuse my question, i'm just trying to understand this.
so what you'd like to see is the lower freqs come down some?
or is the theoretically perfect goal.. the yellow line?
i guess i was expecting a flat line across the graph as theoretically perfect, yet the yellow line isn't flat straight across.
what am i missing in my understanding?
so what you'd like to see is the lower freqs come down some?
or is the theoretically perfect goal.. the yellow line?
i guess i was expecting a flat line across the graph as theoretically perfect, yet the yellow line isn't flat straight across.
what am i missing in my understanding?
mshilarious
Banned
COOLCAT said:
I want to peg that yellow line exactly, in theory. Below 50 Hz and above 12 kHz my drivers are not flat, so I can't do anything about that, but between those ideally I hit that line.
If I had used white noise, that is what you'd see. But I am calibrating to pink noise, which sounds more natural--white noise sounds very bright because humans are more sensitive to high frequencies. Pink noise is more representative of music.
CoolCat
Well-known member
i see...
so tell me more, this is the shte!
Q1) so the tone/sound/pink noise is a continous sweep thru the freq band, varying the db?
2) the software/tone is being played from your pc thru your monitors and the mic is plugged into your soundcard and is recording realtime while the software/pink noise is playing...
and the software plots the "actual"?
when you calibrate what are you doing and what tells you your at 85db, or 80db? i'm still confused on the yellow db trailing downward?this is common for audio? or if its calibrated at 85db why is the chart starting out well below 0db?? confused...
with this it looks like your pretty damn close to the yellow line? i mean its not 10db off or anything. what do you hope to see with the 703? and are you doing upper,mid,low bass traps?
damn thats a lot of questions....
so tell me more, this is the shte!
Q1) so the tone/sound/pink noise is a continous sweep thru the freq band, varying the db?
2) the software/tone is being played from your pc thru your monitors and the mic is plugged into your soundcard and is recording realtime while the software/pink noise is playing...
and the software plots the "actual"?
when you calibrate what are you doing and what tells you your at 85db, or 80db? i'm still confused on the yellow db trailing downward?this is common for audio? or if its calibrated at 85db why is the chart starting out well below 0db?? confused...
with this it looks like your pretty damn close to the yellow line? i mean its not 10db off or anything. what do you hope to see with the 703? and are you doing upper,mid,low bass traps?
damn thats a lot of questions....
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c7sus
Disenfranchised Member
As long as you have RT times of less than 1/2 second and they're pretty uniform from what I understand I would say you're just about there. In the second rendering on the mic across the room you're looking damned good across the spectrum, IMO.
Are you micing from your listening position? Doesn't sound like it from the post.
Are you micing from your listening position? Doesn't sound like it from the post.
mshilarious
Banned
c7sus said:
I haven't measured RT because the room is so far from being done. For example, the big entrance to the hallway needs to be closed off
I'm sure that will make matters somewhat worse. The close-mic position is not far from mix position, but the monitors aren't in the right place yet, they are sitting on each other like a guitar cab or something So the testing here is premature; I'm just doing it to establish procedures. calibrate the crossover and sub, and see about some before-and-after with fiberglass. It would be nice if the befores were worse
CoolCat
Well-known member
i took the old pc out of my car trunk. i was going to dispose of it.
now i slapped it back together, hooked up the 15" monitor....and was thinking maybe i could set up a system for this type testing.
its has a stock audio card. windows xp...466mhz, 8gig. added a 128ram from another pc i had.
so could i just buy this "flat" mic and with plug into the sound card? software needed of course.
what is the soundcard requirements for this type work?
now i slapped it back together, hooked up the 15" monitor....and was thinking maybe i could set up a system for this type testing.
its has a stock audio card. windows xp...466mhz, 8gig. added a 128ram from another pc i had.
so could i just buy this "flat" mic and with plug into the sound card? software needed of course.
what is the soundcard requirements for this type work?