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  • #16
    I appreciate your position, but there's a lot of subjectivity in there.

    The music I listen to and enjoy has plenty of content below 60Hz. 50Hz is probably a bit closer to the average for the majority of music in my library, but I have lots of material strong in the 40s and even 30s. Music without content below 60Hz is generally weak to me, less enjoyable. I enjoy music more when it has the depth of feel that a bit of 40 something Hz undertones imparts, even if they're not the dominant harmonic. My systems also tend to have a bit of a boost / shelf down there to accentuate it, anywhere from 5-15dB of boost based on my recent system measurements. For me, ported is the default and I've never used sealed subs anywhere. What's the harm in extra efficiency IMO? Room gain when applicable just serves to do my personal EQ boosting of the subs for me, but that's my personal preference and I'd never fault someone for disagreeing.

    As for highs, I have an annoying case of tinnitus and hearing loss from too many years in rock bands, but I prefer flat highs up toward 20K myself. Loosing that gives me a sense of dullness that I don't like, almost as if I prefer a little compensation for my hearing loss. Although I definitely don't like to boost the highs above flat and the distortion must remain pretty low.
    Electronics engineer, woofer enthusiast, and musician.
    Wogg Music
    Published projects: PPA100 Bass Guitar Amp, ISO El-Cheapo Sub, Indy 8 2.1 powered sub, MicroSat, SuperNova Minimus

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    • #17
      There's a lot of EDM and other electronic music that goes near 30Hz. If you don't listen to it, then you may not care, but if you do it's certainly part of the experience.
      Francis

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      • #18
        Originally posted by tvrgeek View Post
        I see the same thing on the top. Folks want that nice pretty response to 20K. Well, sorry, unless you are tormenting a dog, not needed. Flat response on the top at the listening point will seem very bright.
        I think a clarification is needed here. You need to distinguish between direct sound (i.e. gated, quasi-anechoic) response and in-room (non-gated) response. Floyd Toole stated it better than I can (my bolding):

        A preference for a downward tilting steady-state room curve is the result of two things:

        1. Beginning with my very first double-blind listening tests in the late 1960s, through the detailed tests in my 1985-86 JAES papers, continuing to this date, the highest rated loudspeakers have had the smoothest, flattest on-axis anechoic response. This is the direct sound.

        2. The normal forward-firing configurations of drivers inevitably start out as omnidirectional at low frequencies, becoming progressively more directional at higher frequencies. The rising bass energy yields a steady-state room curve with a downward tilt.

        A fundamental problem has been the incorrect assumption, made long, long ago (in the age of RTAs), that the audio rule "flat is beautiful" should apply to steady-state room curves, not the direct sound.


        I believe you are referring to in-room response. Indeed, if that is flat the speaker will sound overly bright.
        Last edited by ernperkins; 08-03-2020, 01:01 PM. Reason: typo
        "Everything is nothing without a high sound quality." (Sure Electronics)

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        • #19
          Originally posted by billfitzmaurice View Post
          You can avoid it and cross very close to Fs with a high enough filter order. Neville Thiele's preference was for fifth order. He felt the additional component count was more than made up for by the wider dispersion that a tweeter provides than a midbass or woofer at the same frequency, and the the higher order also provides better protection and lowered THD via better excursion limiting below the pass band.
          It's even better when using DSP. I'm running the Ultimate Equalizer with a M/T crossover of LR8 @ 1200Hz, high sensitivity tweeter that helps limit the excursion. The UE also provides that LR8 with linear phase, too. Being LR it also has the main lobe on-axis.

          dlr
          WinPCD - Windows .NET Passive Crossover Designer

          Dave's Speaker Pages

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          • #20
            Right, I don't even know what EDM is. I listen to classical, jazz, swing, folk, rock, blues, show, old R&B, what we used to call soul, and filk. Modern R&B/Rap is not for me. I am not their target audience. I do not care for a lot of traditional Asian music with only melody and no rhythm. Of course, in the movie room, movies with effects.

            Efficiency? Ported and sealed are the same efficiency. Low extension differs, but the efficiency is the same.

            Part of this may be what one is used to. A lot of material is greatly boosted assuming the player will have a weak system. Not a lot of people go to symphonies enough to "imprint" the natural balance. I can't count the number of times a friend has demonstrated their new whatever, and the bass eq is way boosted. "Listen to the bass" Can't count the number of times I rented a car and the radio bass was turned all the way up. Wogg is far more correct in "feeling light" as apposed to hearing bass.

            Another problem may be in selecting the wrong driver for the job. EBP matters.

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            • #21
              One aspect not mentioned that is important, at least to me, is bass range phase response. I have never heard a ported low-bass system that sounded natural. Really good PR systems are much better, but nothing can duplicate the sound of a properly designed closed box or dipole system. This is almost certainly primarily the phase response. I believe it's also accepted that the one area in which we can distinguish phase response is in the bass range, at least in a loudspeaker system. Headphones are a separate topic.

              On the topic of phase, the more extended the capability of the speaker system, the better the perceived bass response will be. Remember that a highpass (bass rolloff) alters the phase response above rolloff, so a bass box highpass may degrade the bass response, even if the music content only goes down to 60Hz. I've done a lot of experimenting with several bass speakers using, again, the Ultimate Equalizer. Within minutes you can take any bass speaker and audition many different highpass responses, extending them in a manner equivalent to a Linkwitz Transform. The UE also can make the extended response have linear (flat) phase down to 20Hz. You'd be surprised at just how much better an extended response sounds, especially with flat phase. I have extended my system flat to 20Hz, including my dipole system, but flat to 20Hz has proven a bit too much due to the room modes in my case and displacement limitation in the closed (single woofer) box system.

              dlr
              WinPCD - Windows .NET Passive Crossover Designer

              Dave's Speaker Pages

              Comment


              • #22
                Originally posted by billfitzmaurice View Post
                If the room is small enough for cabin gain to fill in the lower octave I agree, but only then. I see zero reason for a ported sub in a car, as cabin gain there will always be enough to fill in the bottom octave, if not two.
                This is not always true. Pictured is the measured transfer function of my daughter's car, a Daihatsu Terios. Turns out that a vented (flat to ~32 Hz) subwoofer seems to be a better match for it, due to the boost in the cabin gain curve between 40 Hz and 60 Hz.
                Click image for larger version

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                Brian Steele
                www.diysubwoofers.org

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                • #23
                  Originally posted by tvrgeek View Post
                  Right, I don't even know what EDM is. I listen to classical, jazz, swing, folk, rock, blues, show, old R&B, what we used to call soul, and filk. Modern R&B/Rap is not for me. I am not their target audience. I do not care for a lot of traditional Asian music with only melody and no rhythm. Of course, in the movie room, movies with effects.

                  Efficiency? Ported and sealed are the same efficiency. Low extension differs, but the efficiency is the same.

                  Part of this may be what one is used to. A lot of material is greatly boosted assuming the player will have a weak system. Not a lot of people go to symphonies enough to "imprint" the natural balance. I can't count the number of times a friend has demonstrated their new whatever, and the bass eq is way boosted. "Listen to the bass" Can't count the number of times I rented a car and the radio bass was turned all the way up. Wogg is far more correct in "feeling light" as apposed to hearing bass.

                  Another problem may be in selecting the wrong driver for the job. EBP matters.
                  EDM is electronic dance music. Some of it is really good. I wish someone could link some content they like that I might find on youtube.

                  Comment


                  • #24
                    Originally posted by rpb View Post

                    EDM is electronic dance music. Some of it is really good. I wish someone could link some content they like that I might find on youtube.
                    One of my all time favorites. Old School Breakbeat Hardcore from the UK:

                    https://www.youtube.com/watch?v=ot6jQXK4Syk

                    The whole album is fantastic. Hard to find, though. Discogs may have a used one.
                    Francis

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                    • #25
                      Originally posted by rpb View Post

                      EDM is electronic dance music. Some of it is really good. I wish someone could link some content they like that I might find on youtube.
                      Old Goth Industrial Rave World Music hybrid:

                      https://www.youtube.com/watch?v=PzRlMld3AAs

                      Once again, great album. Easy to get.
                      Francis

                      Comment


                      • #26
                        Originally posted by fpitas View Post

                        Old Goth Industrial Rave World Music hybrid:

                        https://www.youtube.com/watch?v=PzRlMld3AAs

                        Once again, great album. Easy to get.
                        I'll check it out. Thanks!

                        Comment


                        • #27
                          Originally posted by tvrgeek View Post

                          I suggest, if your sealed were not cutting it and your ported with HP @ 20 are, it is more to do with the specific systems you built. Only you know for sure.

                          Higher crossover to tweeters is not only getting away from Fs, but has more to do with power handling and distortion. Some need to be even higher. HDS and XT25 as examples. Both superb if used well, both really bad if not. Some SB and Seas you can get away with a bit lower. Horn loading helps but a tweeter with enough excursion to push enough air low is subject to teeter-totter. The higher SPL you want, the higher the crossover you had better do. So it depends on your use. The old rules of thumb are still a good place to start. Drivers doing no more than a decade for instance.

                          I avoid very high sound levels. I like my hearing. Old age takes enough toll, so no need to push it.

                          PS: I need that last HP, but I drive a 65 MG, so every one is important.
                          Sealed wasn't cutting it because with an F3 of around 45Hz I was getting nothing out of the room, at 28 foot long and openings to the rest of the house there was no gain.

                          As you pointed out some tweeters just can't handle less than 3 times the Fs for a crossover point. My current tweeters are Morel cat 308s and 378s, still can't decide which ones I like better. They suck up gobs of power 100+ watts with less than .35% distortion at a little over 2 times their Fs, currently crossed over at 1600

                          Yup, every last HP counts on old British cars. Growing up the neighbors had MGBs, TR3s and Bugeyes. Learned a lot watching and helping wrench on them.

                          I still listen at stupid loud levels on occasion, just have to, kinda like needing to let the car run, they make Z rated tires for a reason. I do wear hearing protection for chainsaw, chipper, at the range and have started wearing a single plug in my gun side ear when hunting.

                          You said that anything below 20Hz is guaranteed to be 100% distortion because of the THX spec. And then you said you watch movies with the effects but you don't know why people build sub 20Hz systems. I don't think you understand that THX is independent of the actual codec used to record the audio track. There is no THX codec. It's an unpublished group of standards that says this equipment will play back audio and video at what should be higher quality because of the hardware and/or software involved. As an example in an AVR THX effects are applied after the audio track is decoded, be it Dolby, DTS, pcm, whatever. It's basically an audio special effect that and I quote "....THX Ultra2 Plus receivers also feature proprietary THX technologies (e.g., THX Mode) which accurately translate movie soundtracks for home theater playback". The actual soundtrack is usually recorded using Dolby or DTS codecs. So if we take a look at some published Dolby docs the LFE channel is actually spec'd between 3Hz and 120Hz and the main channels between 3Hz and 20Khz, Just because THX spec'd devices don't ever reference below 20Hz doesn't mean content doesn't exist. Go get yourself a good recording of the 1812 overture and do a FFT on the canon shots. Lots of sub 10 Hz content. And if canon shots have have a lot of low frequency infrasonic sound what have you been missing watching movies with a sound system that rolls off high?

                          As an aside, the closest thing I've ever seen to a publicly available THX spec is an article over at home theatre hifi. Didn't go into as much detail as I would like but it at least paints broad strokes of what the spec covers for various pieces of hardware. https://hometheaterhifi.com/editoria...how-to-use-it/

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                          • #28
                            Originally posted by tvrgeek View Post
                            Right, I don't even know what EDM is. I listen to classical, jazz, swing, folk, rock, blues, show, old R&B, what we used to call soul, and filk. Modern R&B/Rap is not for me. I am not their target audience. I do not care for a lot of traditional Asian music with only melody and no rhythm. Of course, in the movie room, movies with effects.

                            Efficiency? Ported and sealed are the same efficiency. Low extension differs, but the efficiency is the same.

                            Part of this may be what one is used to. A lot of material is greatly boosted assuming the player will have a weak system. Not a lot of people go to symphonies enough to "imprint" the natural balance. I can't count the number of times a friend has demonstrated their new whatever, and the bass eq is way boosted. "Listen to the bass" Can't count the number of times I rented a car and the radio bass was turned all the way up. Wogg is far more correct in "feeling light" as apposed to hearing bass.

                            Another problem may be in selecting the wrong driver for the job. EBP matters.
                            I'm referencing efficiency at a specific frequency, tying efficiency to extension. So, if a woofer in a ported enclosure has 10+ dB per watt higher output than a sealed enclosure at say 30Hz, I'm calling that efficiency but qualified at 30Hz. Sure, you can boost a sealed cabinet to achieve the same response, but that imparts the same transfer function anyway and simply draws far more power. Once you add boost EQ, similar phase and group delay issues appear for sealed alignments. dlr 's alignment experiments sound like they've uncovered a lot more nuance than that, which I find interesting.

                            It's more than a body feel for me as well, I don't listen loud enough to really get the gut punch. Even at low volumes, the low fundamentals will pique my interest and I'm clearly hearing them rather than feeling. For example... low volume sleepy time listening to some Enya, there are low fundamentals in the score that just expand the space much larger than it would be otherwise.

                            IMO of course... my position is just as subjective as everyone else's

                            I'm in total agreement with: grossly over-boosted bass, bad ported designs, bad subwoofer integration with the mains.... it all has to be done well.
                            Electronics engineer, woofer enthusiast, and musician.
                            Wogg Music
                            Published projects: PPA100 Bass Guitar Amp, ISO El-Cheapo Sub, Indy 8 2.1 powered sub, MicroSat, SuperNova Minimus

                            Comment


                            • #29
                              Originally posted by tvrgeek View Post

                              Chill out. This is more about new builders targeting unrealistic goals on this and other forums I have visited. Helpful hint from 45 years of building speakers, not an attack.
                              From the responses, it appears those 'unrealistic goals' are not so unrealistic, but you have sparked an informative thread.
                              http://techtalk.parts-express.com/fo...khanspires-but
                              http://techtalk.parts-express.com/fo...pico-neo-build
                              http://techtalk.parts-express.com/fo...ensation-build

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                              • #30
                                EDM, electric dinosaur music.

                                https://www.youtube.com/watch?v=zYKupOsaJmk

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