Maybe I will do that tomorrow, just to see. That way I could directly compare the 2 different pink noise sources. Has anyone explored this and confirmed an accurate pink noise recording that is available commercially or online?Īctually, it might be simple to just route the pink noise signal directly into the RTA input without going through the amp, speaker, and mic, and the FFT graph should be flat. Before I go back to the books to review the physics of pink noise and then record both pink noise sources into Audition to do spectral analyses, here is my question, in case someone has been down this road before: Inaccurate pink noise, ie where the power in each octave is not constant across the frequency range of interest, would make a major difference in setting crossovers, and other system adjustments using pink noise. The pink noise "generator" in TrueRTA actually sounds like a looped recording, not a generator, and it seems to be seriously deficient in some of the lower frequencies. I thought pink noise was pink noise, but apparently there are shades of pink out there. I readjusted the DSP filters to get a flat response using the Stereophile pink noise recording, and the sub sounded great.īefore you kick me out of the LAB into the Lounge or the Basement, let me ask my question.
![calibrazione truerta calibrazione truerta](https://trueaudio.com/images/rta_0404_1k.gif)
The Stereophile CD pink noise sounded like the TrueRTA pink noise with the bass cranked up 10 dB! The frequency response looked much different on the TrueRTA screen when I used the Stereophile pink noise instead of the TrueRTA pink noise. Finally, I pulled out a Stereophile Test CD with pink noise on it and played that. This was not due to room modes or mic LF rolloff, I used the same Earthworks TC30K mic at 1/4" from the speaker cone for all measurements.
![calibrazione truerta calibrazione truerta](https://www.researchgate.net/publication/346864850/figure/fig4/AS:998493292339203@1615070760426/Neuronal-recordings-A-Raster-plot-of-lick-responses-black-ticks-to-rewardpredicting_Q320.jpg)
![calibrazione truerta calibrazione truerta](https://www.researchgate.net/publication/325151653/figure/fig5/AS:626546872156160@1526391823004/Sound-calibration-and-delivery-A-Components-computer-1-miniUSB-USB-A-cable-2.png)
The 31, 40, and 50 Hz tones were 5-15 dB louder on the RTA screen than the 60, 80, and 100 Hz tones. I then tried a test CD with 31 sine wave tones at equal amplitude, at 20, 25, 31, 40 Hz etc. I kept finding that the frequency response which looked flat on the RTA sounded way too hyped in the bass frequencies when I played music I know well through the sub.
#Calibrazione truerta generator
I was using the pink noise generator built into TrueRTA, adjusting the PEQ filters in the XP4080 to get a flat response over the 30-90 Hz range. Today I was playing around with TrueRTA (1/24th octave) and my new Xilica XP4080 trying to emulate a Linkwitz transform filter to flatten the response and increase the low frequency extension of an old subwoofer.