Bennett Prescott wrote on Sat, 08 January 2011 11:11 |
Friends, Romans, Countrymen... I am going to write an article about different DSP platforms, in an attempt to have a semi-definitive source to point people to the next time I get asked why those Driverack settings sound so funny in the KT processor. I would be touched if y'all would do me an enormous favor and help me get measurements from different processing platforms. I have designed an imaginary loudspeaker preset that I think will stress the differences in their filter definitions. If anyone thinks they have better ideas, speak now or forever hold your peace. I am trying to make it somewhat realistic while fitting within the filter capabilities every processor is likely to have. Any reasonably mainstream processor welcome. These exact frequencies and bandwidths may not be available (on purpose), please get as close as possible. If you would like to help, please program these filters into whatever DSP you have at hand: High Pass - Bessel - 97Hz 18db/octave Bell - 280Hz - 2 octaves/0.66 Q -4.5dB Bell - 176Hz - 0.6 octaves/2.39 Q +5dB Bell - 6.35kHz - 1/8 octave/11.54Q -8dB Shelf - 8kHz - 1.6 octave/0.86Q/6dB +5.5dB Measure with Smaart, using the standard internal pink noise source as a reference. Use 16 averages, 48k sample rate, and 24bit, no smoothing. Use auto small to set your delay compensation. Please take a measurement with a 16K FFT and one with FPPO. If you could also send me an IR file that would be invaluable. Please label your measurements and email them to me, don't post them here... I need to know which processor which measurement came from, but I don't want everyone to know. Anyone who wants to go even further and put in bandwidth instead of Q and take another measurement of that would receive another free Internet. bennettprescott at gmail dot com Thanks in advance to those of you with a little time to waste and some measurement chops! |
Bennett Prescott wrote on Sat, 08 January 2011 13:20 |
JR, I'm not trying to solve the problem, I'm just trying to document it. I especially do not plan on naming names. I just want people to understand that a difference exists and to get a rough idea of its magnitude. If people will at least convert between Q and bandwidth before entering settings into the wrong processor I will consider it a victory. Hell, there are settings out there that when I plugged them into the correct processor looked like they were for a different loudspeaker, so there's more problems there than I want to address. |
Bennett Prescott wrote on Sat, 08 January 2011 15:55 |
Ivan, This month? |
Ivan Beaver wrote on Sat, 08 January 2011 17:40 | ||
I'll try to find some time. |
Kemper Watson wrote on Sun, 09 January 2011 04:15 | ||||
Do you have a Driverack 260? I could let you use mine if it would help. |
Chad Johnson wrote on Sat, 08 January 2011 23:56 |
Bennett Do you think there's any benefit to a similar approach to the EQ sections on digital consoles? I know it would be another project to undertake, but I always thought it would be interesting to know how different units would respond to different settings. I will be able to contribute V7 shots of some DSP units. Are you coordinating different models in offline conversations? No sense taking the time if someone else is doing the same model. -Chad |
Chad Johnson wrote on Sat, 08 January 2011 22:56 |
Bennett Do you think there's any benefit to a similar approach to the EQ sections on digital consoles? I know it would be another project to undertake, but I always thought it would be interesting to know how different units would respond to different settings. I will be able to contribute V7 shots of some DSP units. Are you coordinating different models in offline conversations? No sense taking the time if someone else is doing the same model. -Chad |
Bennett Prescott wrote on Sun, 09 January 2011 15:16 |
Chad, I'm with Ivan on this one, I don't know anyone who takes settings from one console and manually programs them one channel at a time into another console... maybe I just haven't met them. I have done no offline coordination as of yet, but I also have only one measurement so far! |
Ivan Beaver wrote on Sun, 09 January 2011 14:14 | ||
And if you were so picky aobut that, then that would also be assuming that the sound systems were exactly alike-which they are not-from room to room. Maybe similar with like cabinets-but still not the same. |
Chad Johnson wrote on Wed, 12 January 2011 00:17 |
Not picky at all. Of course console EQ is for artistic elements and not for a reference room tune or speaker processing. I understand the reasoning in DSP standardization and have talked about it here myself. I was simply mentioning I myself have been curious in the past how different digital consoles come up with their EQ algorithms. I'm most experienced with Yamaha digital console EQ and compared to a Profile, for instance, I find there is a difference in how I use them. It might have more to do with looking at the displays and mixing with eyes more than ears. |