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Here are some itching funnies (and ready made for REW targets) I’d like to share. First, Let’s take the same set of Impulse Responses obtained by Sweeps and average* them 3 ways in REW : Frequency Dependent Windowed RMS Average, RMS Average, FDW Vector Average. I add results from Real Time Analysis of Pink Noise measured while Moving Microphone. There have been some changes between MMM and Sweeps times but still there’s a good consistency between RMS Av and MMM results while FDW RMS Av and FDW VA yield radically different results, in my room with my speakers. Hence, you’d better know what you (or the expert and/or commercial software you would trust) are/is to pick. If I am to obtain textbook Impulse and Step Response (thanks to RePhase) I have to pick the FDW VA. If I set Phase with the FDW VA and then set Amplitude on RMS Av or MMM, Impulse and Step remain OK but not as pretty. This raises the question of what but the VA is a commercial software picking if it is to display textbook Phase related results. And that conflicts, unless What You See is Not What You Get, with the choices of targets (neither B&K nor Harman dubbed them such) such as RR1 or B&K. RR1 low end extends B&K that dates back to Pink Noise and RTA time, so no Impulse Response, no FDW, it’s Steady State that is measured… So, if one is to choose a target related to Steady State, one should better apply it on Steady State measurement… *L and R are in different environments in my room and hence measure differently below 300 but for the sake of simplicity they are here added/averaged

Goal /the incumbent filters: get a faster more “agile” articulate intelligible sound while keeping big bass extension Crisis started when I switched off convolution to compare my setup + original Argo of Jamal at Alambra to the needle drop sold as dsd download (yes yes and to much praise by Acousticsounds ; meaningless comparison since I doubt the needle drop is sourced from the distorting but sometimes gloriously tubey original) : though convolved DSD was a clear winner over non convolved DSD or LP, it sounded too analog and too tamed, fat and slow. Findings Do eQ, REW is donations welcome free : try it (but you need a microphone). Doubt you get comparable results from power usb whathaveyou cables… RR1 (as in https://www.innerfidelity.com/content/warren-tenbrooks-summary-head-measurements-harman) is a mighty good target house curve Mind applied smoothing : a predicted response curve matching Bob Katz’s target (flat to 1 k, 6 dB downward to 20K ) created with “Psyschoacoustic” smoothing in REW resembles RR1 when looked at in VAR or traditional (ie 1/3 octave) smoothing mode (Bob Katz uses Acourate’s Psychoacoustic) Multiply measurements but pick the one that resembles average, not the average summation (ie in REW the Psychoacoustic profiling only applies to single measurements ; as do many options) Avoid messing with frequencies above Minimum Phase zones galore (on the left half of frequencies) (850 Hz max here, different from the theoretical 300). Lower Shelves are great : found out that RR1 paralleled the measured response in my room and that a 5 dB 600 Hz start LS puts frequencies below 600 on the RR1 target Dare switch to Manual. Automatic was not at ease, I took the time to flatten the bumps and, up to 9 dB in Minimum Phase zones, fill. Listen (Stereophile CD3 and best of Chesky 2 have been most helpful, mainly the tracks with moving point sources (acoustic clickers, cowbell…) ). I did not have at hand the mike I created the measurements with, only a iPhone + SPL app, useless below 250 and probably giving a false 3 dB bump reading at 500, but measuring would be great too. In the end listening matters more. Bottom line :girlfriend threatened to quit madman but is as amazed as I am in the end : WOW ! Goal met

Hi, I wonder if someone could provide a step-by-step guide to achieving room correction using REW and HQ Player. I tried to find a tutorial but the information is scarce and spread all over the web... It's been years since I last used REW to measure the frequency response at the listening spot. I have a mic, REW and I'm ready to go. Thanks, Ricardo

There's Nyquist, there's the actual bandwidth limited range in relation with the actual microphones range and arguments for 192 helping reconstructing transients. However there might be a better argument for using even more space disk : multichannel even for stereo. I'm convinced that what I discovered with MCH Electric Ladyland goes far beyond eventual differences in remastering talents or marketing strategies (Bernie Grundman signs the Stereo that is soso while Eddie Kramer signs the MCH ; the latter supervised the gorgeous Mono LP Axis signed by the former who delivers a soso Mono Mix in the recent SACD where the Stereo shines...). Fact is MCH is more than 2.5 x heavier than the Stereo and I bet it's better use of space than 192 vs 96. Maybe it is also due to LFE and engineers daring to go deep low but MCH downfolded into Stereo via HQP offers aural sculptures of the bass line and of the kick drum that are really reminiscent of live gigs impressions. Even soundstage is deeper that what I'm accustomed to. I'm thus starting a journey into MCH (to be played on my stereo) and suggestions and comments are welcome. As of Rock/Pop I start with https://www.quadraphonicquad.com/TabbedPollChart.htm Edited on December the 5th : I have not experimented with Classical or Acoustic Jazz but dig that when MCH aims at recreating natural acoustics, reverb, etc, down mixing to Stereo is a non sense. However, when reproducing (better, those who know say) the natural acoustics of the concert hall etc is not the goal, ie with Talking Heads, Steely Dan or Bjork, MCH to Stereo offers better bass delineation, smoother and more natural vocals and more noticeable soundstage vs the standard Stereo.

I'm still an audiophile when I watch TV. And my computer is now by best source for ripped movies too since I am back to the future with a Kuro 500 Plasma TV (that doesn't have the capability to process my Blu-Ray remuxes) I could do with the included in IINA (new os x player based on mpv) eQ but I want better. However I must confess I have not been able to write a correct syntax to get IINA trigger FFmpeg afir that would convolve the IR filters I have designed for HQplayer. Anyone can help?

I'm trying to get an audiophile sound when playing remux ripped blu-rays on my computer. Getting the right syntax to make afir work in FFmpeg would be a way. At the moment I follow Bob Stern's advice to try Audio Hijack to capture the audio output of my video player app and put an AU in. Allloy 2 works but I know I can beat simple eQ with my filters REW/RePhase designed for HQP. I can't get iZotope Trash nor Fog convolver to simply convolve my own 2 channels FIR. The simple but mighty old LAconvolver works and beats Alloy 2 yet. However it resamples my filters to 44.1 and I'd like to keep things 24/96 at least. Furthermore, there is a several second lag between image and sound with LAConcolver. I'll try to sync via video player app but would definetely prefer a better performing solution Any suggestion?

The measurements of actual concert halls presented here https://pdfs.semanticscholar.org/e4c9/b3222f26472f6ba12e7fea900c2edb10c14c.pdf show a much more drastic drop of the frequencies above 5K than suggested by target curves such as B&K C, Bob Katz's or HK RR1 The bass roll-off is consistent with the FR of the monitors used while the drastic treble roll off appears to be the hall response. I recently frowned at the measurements of an expensive Audio Research amp (see Stereophile) but this, and some solutions blamed for rolloff, would it be filters cables or what have you, might well answer a respectable quest. Respectably ? Personally, I simply created new convolution files to mimic SI R2, preferred by assessors cf https://users.aalto.fi/~ktlokki/Publs/JASA_lokki2012.pdf Although I can't say I suffered from brightness with my previous filters, the first impression is very good and paradoxal : more precision in instruments placement (while I had in mind that more treble favours soundstage)

I have previously posted asking how to configure JRiver to send stereo to multiple zones. I have now come up with a solution. This is the best I could manage without moving to pro audio type solution. I would still like to implement a master volume for the convolution channels but for now I guess I have to live with this setup. It was a slow progress from 2 speakers to the current 26 speakers setup. It took me 5 years to get the 4 speakers correct and last few months for the rest of the speakers. The convolution works for stereo setup too and it doesn't cost much. p.s. Where is the "Preview" button?