Download Dirac Target Curves
Saija Grzegorek
After reading your posts, I have modified my +4dB to -4dB target slightly.
Adjusted target beetween 40-100Hz to match more closely to speakers response.
Now I like it. SVS Prime Pinnacle
Target26981572 314 KB
Here one of the adjusted graphs- my speakers are flat, so we followed them with some adjustments in the low and high frequencies. I have an open space next to the right column so the two speakers have individual curves
I agree with you. Overall its sounds a bit bassy to me, so will lower the graph anyway. One thing I noticed is that no dirac gives me a better stage, bot sure where it comes from. Also the very low end sounds a bit wider.
The Harman target curve for speakers only really specifies a 10db slope from 20Hz to 20KHz. Talking to an acoustic engineer about this, I was told that according to the studies, the slope is an absolute from 200Hz up, but from 200Hz DOWN there's no clear answer.
Dirac Live's default target curves are known to sound bass-shy. Here's a choice of target curves based on Harman research. These target curves can be directly loaded from within Dirac Live 2/3. They differ in the amount of bass boost.
Note: Use the very same target curve for all your speakers including the subwoofer. Do NOT use different target curves amongst speakers in the crossover region to the subwoofer(s) or you'll end up with a combined response that no longer follows the intended curve. Adjust high frequency fall-off according to your speaker's in-room response.
Well I have to tell you that no speaker is perfect, and in any media room nomatter its size, configuration and correcting apparatus, there will be at best +/- 5 to 10 dB peaks and troughs in frequency response, plus manufacturers tunethe sound of every piece of equipment in the chain to what they consider to beproper sound. Plus, until this program, I've been very dis-satisfied with theresults obtained with the other correction programs out there; the curvesobtained being what the manufacturer considered to be correct.
What the Room Correction Suite can do is not only give you close to perfectlyflat frequency response curves on up to 8 loudspeakers in your room, but willthen allow you to adjust the frequency response of each individual speaker toany parameters you wish. See thislink for technical descriptions of how it functions. Why would one want other than aflat response? Because in a concert hall you are not being bombarded byperfectly flat sound, but a response that depends on the hall you are in,your position in the hall and where and how the microphones are picking up thatsound for the recording. Then you have the recording engineer's take on what therecording should sound like. So believe it or not, most people do not preferruler flat response from their recordings. That's one of the reasons eachloudspeaker sounds different as each is tuned to what their developer prefersfor sound.
One then puts the microphone in the ideal listening position and presses thestart button. A frequency sweep then runs for each loudspeaker. The program thenanalyzes the data and has the person move the microphone to the next positionwhere the frequency sweep and analysis occurs. When completed, one goes on toStep Five, Filter Design. Thefrequency and time delay of each speaker and driver is graphed out. At thispoint, one can make corrections through crossover adjustments, driver distance,speaker position, etc., then go back to the Measurements page, cross out theprevious frequency sweeps and check the corrected speaker response like withother programs. Or, and here's where the program starts to shine, byhitting the optimize button, the computer analyzes the curves and computes thecorrection curves for each speaker to make them flat both in the frequencyand time domains. One then saves the corrected curves.
One then opens the Dirac Audio ProcessorController, loads the corrected curves to it, set the computer'ssound controller to use the Dirac Controller, then set the Dirac controller'soutput to whatever output from the computer that you use, and play your music.One can turn the processor on or off to determine whether the curve's soundoutput is exactly what you want. But here's where I disagree with the programdevelopers. As you can see above, what they do is produce corrected frequencycurves that slope down by about 3 dB from 20 to 20 kHz. I asked them about thisand this is their reasoning:
The automatic curve has a slope or tilt of -0.5 dB peroctave. Its range is calculated from the measurements. In our experience, atarget curve that is slightly tilting down towards high frequencies (like theauto-target) is often preferable - a flat target often sounds too bright. Aloudspeaker with a flat on-axis response will usually have a slightly tiltingin-room response. So, the tilt in our target is simply there to take intoaccount that the loudspeaker is operating in a room. This may not fit well inall rooms as they have different acoustical treatments. This being said, you canof course almost always get a bit better results than the auto target whentweaking manually if you want to put some time into it.
On listening to these corrected curves, compared to my uncorrected speakersafter I had set the crossovers up as flat as possible, the sound was clean butsomewhat dull and shaded, due to that decreasing slope. You may find differentlyon your speakers. Yet here's where the program shines. The curves produced havea line through them with four moveable points present on the graphs, or bydouble clicking on the target line adding as many as you wish, to adjust thefrequency curves. One can then move those points to correct in a smooth fashionthe frequency curve to just about any shape one wants. Thus the program correctsnarrow frequency anomalies and this corrects for wide frequency slopes. Thiswould include increasing or decreasing the lowest and highest frequenciesreproduced and adjust the entire slope to produce anything from perfectly flatto sloping up or downward at either end, to increasing or decreasing the outputof an area of the curve.
7. By being able to manipulate the program's curves, I was able to voice myspeakers in such a way that I actually felt the closest I've ever been to beingin a concert hall. My system ended up sounding best by putting a 3 dB smoothupward slope from 20 Hz to 20 kHz on the main speakers with almost flat frequencyresponse on the surround speakers. Through manipulation of the curves you'd beable to do the same to optimize your speaker-room interaction.
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