Measuring tlahs

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MissileCrisis
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Measuring tlahs

#1 Post by MissileCrisis »

How does one measure a high frequency speaker such as the tlah? I remember reading that they tend to need two different measurements put together. If someone could elaborate on this I would greatly appreciate it as my tlah seems to have a huge rolloff at 12k. Measured Nearfield. The speakers sound much better at the other side of the room (13 ft) as expected.
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2 x TLAH
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1 Tuba 60 (lab 12, 20 inch)
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Michael Ewald Hansen
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Re: Measuring tlahs

#2 Post by Michael Ewald Hansen »

MissileCrisis wrote:How does one measure a high frequency speaker such as the tlah? I remember reading that they tend to need two different measurements put together. If someone could elaborate on this I would greatly appreciate it as my tlah seems to have a huge rolloff at 12k. Measured Nearfield. The speakers sound much better at the other side of the room (13 ft) as expected.
Could you post your measurements? That roll-off is the same everywhere in the room?

I doubt you will ever miss much above 12khz imo - I can't hear much beyond 16khz and 12>16khz is just half an octave..
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MissileCrisis
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Re: Measuring tlahs

#3 Post by MissileCrisis »

I will try measuring from other points In the room. The reason I did it the way I did is because I wanted the signal in the 75 db range and pressing the capture button on my stationary computer is easier when I'm near it. Pink noise is obnoxious. Should I be using sweeps? If so how does one record that with rew?
Built
2 x TLAH
1 Titan 39 (lab 12, 15 inch)
1 Tuba 60 (lab 12, 20 inch)
SLA Center
2 x Mini MLTP subwoofers
1 x 212 TH (custom)
2 x Mini-Karlsonators
Owned, but not built
2 x Jack 12 (2512, melded)

MissileCrisis
Posts: 1128
Joined: Sat Dec 15, 2012 1:30 pm
Location: Walnut Creek, California

Re: Measuring tlahs

#4 Post by MissileCrisis »

I will post measurements tonight.
Built
2 x TLAH
1 Titan 39 (lab 12, 15 inch)
1 Tuba 60 (lab 12, 20 inch)
SLA Center
2 x Mini MLTP subwoofers
1 x 212 TH (custom)
2 x Mini-Karlsonators
Owned, but not built
2 x Jack 12 (2512, melded)

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Michael Ewald Hansen
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Re: Measuring tlahs

#5 Post by Michael Ewald Hansen »

MissileCrisis wrote:I will try measuring from other points In the room. The reason I did it the way I did is because I wanted the signal in the 75 db range and pressing the capture button on my stationary computer is easier when I'm near it. Pink noise is obnoxious. Should I be using sweeps? If so how does one record that with rew?
Don't care about getting the signal in a specific range - to begin with, just get measurements from where you want to listen to music/movies and start working from there.. If you haven't calibrated REW with a precise SPL meter you can't rely on REW to show the correct spl..

I like to use sweeps, but I also use pink noise to soublecheck results etc..
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Bill Fitzmaurice
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Re: Measuring tlahs

#6 Post by Bill Fitzmaurice »

MissileCrisis wrote:How does one measure a high frequency speaker such as the tlah? I remember reading that they tend to need two different measurements put together.
You do if you're measuring outdoors for a half-space anechoic result. In room for the purpose of EQ measure them at the listening position, half-space anechoic being moot.
If someone could elaborate on this I would greatly appreciate it as my tlah seems to have a huge rolloff at 12k. Measured Nearfield.
You cannot get an accurate result measuring a line array nearfield.

MissileCrisis
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Re: Measuring tlahs

#7 Post by MissileCrisis »

Thanks for the feedback. I'll do another test as far back as my room allows until I get to measure somewhere bigger. I have to say that these things really fill the room/space they are in (still only having heard a single I can't comment on imaging yet). They sound great when you back up, still haven't done a proper demo so look for a review this weekend.
Built
2 x TLAH
1 Titan 39 (lab 12, 15 inch)
1 Tuba 60 (lab 12, 20 inch)
SLA Center
2 x Mini MLTP subwoofers
1 x 212 TH (custom)
2 x Mini-Karlsonators
Owned, but not built
2 x Jack 12 (2512, melded)

MissileCrisis
Posts: 1128
Joined: Sat Dec 15, 2012 1:30 pm
Location: Walnut Creek, California

Re: Measuring tlahs

#8 Post by MissileCrisis »

Michael Ewald Hansen wrote:
MissileCrisis wrote:I will try measuring from other points In the room. The reason I did it the way I did is because I wanted the signal in the 75 db range and pressing the capture button on my stationary computer is easier when I'm near it. Pink noise is obnoxious. Should I be using sweeps? If so how does one record that with rew?
Don't care about getting the signal in a specific range - to begin with, just get measurements from where you want to listen to music/movies and start working from there.. If you haven't calibrated REW with a precise SPL meter you can't rely on REW to show the correct spl..

I like to use sweeps, but I also use pink noise to soublecheck results etc..
I used a cheap spl meter for volume calibration but it's only accurate to 3 db ish. How do you get a plot when using a sweep?
Built
2 x TLAH
1 Titan 39 (lab 12, 15 inch)
1 Tuba 60 (lab 12, 20 inch)
SLA Center
2 x Mini MLTP subwoofers
1 x 212 TH (custom)
2 x Mini-Karlsonators
Owned, but not built
2 x Jack 12 (2512, melded)

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Michael Ewald Hansen
Posts: 638
Joined: Tue Aug 16, 2011 10:43 am
Location: Denmark

Re: Measuring tlahs

#9 Post by Michael Ewald Hansen »

MissileCrisis wrote:
Michael Ewald Hansen wrote:
MissileCrisis wrote:I will try measuring from other points In the room. The reason I did it the way I did is because I wanted the signal in the 75 db range and pressing the capture button on my stationary computer is easier when I'm near it. Pink noise is obnoxious. Should I be using sweeps? If so how does one record that with rew?
Don't care about getting the signal in a specific range - to begin with, just get measurements from where you want to listen to music/movies and start working from there.. If you haven't calibrated REW with a precise SPL meter you can't rely on REW to show the correct spl..

I like to use sweeps, but I also use pink noise to soublecheck results etc..
I used a cheap spl meter for volume calibration but it's only accurate to 3 db ish. How do you get a plot when using a sweep?
Did you calibrate your soundcard aswell? That should be done imo to get more accurate results - its not imperative, but you might aswell do it for higher accuracy..

Just click measure in REW - and then do a sweep.. Then youll get a plot in the main window..
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MissileCrisis
Posts: 1128
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Location: Walnut Creek, California

Re: Measuring tlahs

#10 Post by MissileCrisis »

I'm using a nuforce udac for output and a blue I icicle usb Xlr preamp. So by sound card measurement would that account for both transfer functions? I know the udac is darn flat but I have no clue about the Xlr interface so I'll try that.
Built
2 x TLAH
1 Titan 39 (lab 12, 15 inch)
1 Tuba 60 (lab 12, 20 inch)
SLA Center
2 x Mini MLTP subwoofers
1 x 212 TH (custom)
2 x Mini-Karlsonators
Owned, but not built
2 x Jack 12 (2512, melded)

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