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Kvalsvoll last won the day on January 23

Kvalsvoll had the most liked content!

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About Kvalsvoll

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    Bass Overlord

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  1. Kvalsvoll

    Bulding the Room2 listening room

    New article about bass-system calibration: https://www.kvalsvoll.com/blog/2019/02/10/calibrating-a-bass-system/
  2. Kvalsvoll

    Bulding the Room2 listening room

    Small will still not be the same, because directivity will be different. Unless directivity is designed to be similar, of course. Active does not make any difference, and eq can not change decay profile, which is a result from room and speaker radiation. The solution lies in the physical acoustic design of the speaker. Active is necessary to solve some issues, such as crossover at lower frequencies, and delay between drivers where this is necessary. Proper crossover between bass system and main speaker must be active, because it is too difficult and costly to make a passive network that works, and the quite large delay needed on mains can not be solved passive. Subwoofer usually requires more power, too. But then all this is not necessarily true either, because when I designed the C2 (1992) I made a passive crossover at 150hz, so it is possible, using computer simulation. But timing will be off, this ends up as a text-book 4. order crossover, with option for individual delay it is possible to design crossovers with no timing problems. The new F105 is a small speaker with 5" lf driver and dome hf with moderate horn loading. The cabinet is a damped dipole with resistive acoustic ports. Directivity is controlled all the way down to 100hz, where it already has started to roll of. Design f range is 120hz and up. With a small subwoofer - will be half size of a V6 - that can be placed near boundaries, with dsp and eq, this gives a small system that will work well in normal rooms. The response is much smoother and more similar in different locations and rooms due to the directivity, even when this directivity control is quite small. But it doen't sound like a big speaker, regardless of sound volume. This small speaker would not benefit from active configuration, but the system as a whole is active where the crossover to the bass system needs to be done in a processor, and the bass system need dsp with eq. The next speaker will be a little larger, with 2x 5" lf drivers of a very different type. The goal for this one is to achieve good transient response - as long as you keep the volume down.
  3. Kvalsvoll

    Bulding the Room2 listening room

    English version of the small speaker article: https://www.kvalsvoll.com/blog/2018/10/20/can-a-small-speaker-perform-like-a-big/ To discuss or comment, you can reply here in this thread. Small speakers without the sound compromise have always been wanted, and there are several new speaker offerings claiming the problem is solved - small sounds as good as huge. But it doesn't. This article tries to describe some of the most important reasons for this.
  4. Kvalsvoll

    Bulding the Room2 listening room

    New article about power requirements: https://www.kvalsvoll.com/blog/2018/12/02/how-much-power-do-i-need/ Info on power requirements for active or bass-managed systems is interesting - reducing the bandwidth does not reduce peak power requirements.
  5. Doing a proper bass-eq takes time and effort, and as you do more of them you start to notice that experience is nice to have. Yes, you need to listen, and since a movie is quite long, with lots of scenes and sound effects, this will be a time-consuming process if you want to be sure you get the best possible result within constraints given by you skills and the soundtrack you have. But we only watch the movie once - usually. Kind of like how GOT (a person living in Norway) put it about skiing - the conditions really does not matter when climbing and skiing a mountain, because you only ski it once. It is what it is, that one time. If it was perfect, well, good, but if it was icy and crusty, or the bass in the movie was less than perfect in some scenes, that is what we had. But we do not have to re-live it over and over again. This also means there is a limit to how much effort you want to put into fixing someone else's mistakes on a movie. So I usually end up picking a couple scenes, and do beq on lcr+lfe.
  6. I see your point where individual bass-eq for all channels including surround is the ultimate solution, and can in some cases be a significant improvement, as when surround effects that has wide frequency range are not mixed in to the lfe channel, and those surround channels are filtered somewhere in the process. But still, I claim most of the performance gain with bass-eq can be had with beq on the bass-managed signal, which is the only practical solution for most people. Then you miss out the correct correction for surround - as well as lcr - because the adjustments you make are weighted +10dB hot on the lfe channel, giving too little boost on lcr+sr. In a world where even very, VERY few dedicated enthusiasts knows what bass-eq means, there is a huge potential for improvement that will be possible on most serious systems, because they all have dsp on the bass-system, which can be used to implement BEQ that gives 80-90% of the improvement. Compared to no BEQ, there is a huge improvement still, and the dedicated channels BEQ will only be a small step above that. 40hz or 50hz for surrounds is more like the same, when talking about the real thing, which means full frequency range - full capacity.
  7. It is not strange that something with +60dB ulf boost on surround channels looks odd, because this is very likely mostly noise. Keep in mind that no studio or cinema can reproduce low frequencies on the surround channels, whatever is there below around 50hz was never part of the sound design. The most important to fix is lfe and lcr, that is where the big difference lies.
  8. Kvalsvoll

    The Bass EQ for Movies Thread

    @3ll3d00d, I do follow and appreciate the excellent work you have done on the beqdesigner. Especially since it is obvious now that the best we can hope for is movie sound that responds well to bass-eq, there will never be a situation where you can assume the sound is perfect from the provider. I also follow, or at least make an attempt to see what is going on in the soundbar-forum thread.
  9. Kvalsvoll

    The Bass EQ for Movies Thread

    Apply gain -10dB before filtering, that should leave enough headroom. After applying all filters, you can fix the gain (+10dB), and perhaps give a warning if clipping occurs. But remember that for dsp processing during playback there may be more headroom available, if the dsp is located after master volume in the signal chain.
  10. Kvalsvoll

    The Bass EQ for Movies Thread

    I may be the only one trying to run beqdesigner on linux, so it's like you did this for me, and I feel obliged to test it. I will see if I get the motivation to give it another try, requires some effort to upgrade to the right version of everything, including the right python version. I will report back when I have tried it, and thanks.
  11. Kvalsvoll

    The Bass EQ for Movies Thread

    Kodi uses alsa on my machine, and this dsp can use alsa. But it will not work for movies, because audio is sent to hdmi directly as passthrough, for external decode in the av processor. It would be possible to configure to allow software processing if the movie audio is re-encoded to pcm, but then you still would need to extract, decode, encode and re-mux. Options here are severely limited due to the proprietary formats of audio in movies. Which leaves processing post-bm in the bass-system dsp is the best option for quick and reasonable quality bass-eq. This also eliminates problems with clipping.
  12. Kvalsvoll

    The Bass EQ for Movies Thread

    There is no dsp available on the computer. But that is possible to fix, this is a linux machine running ubuntu and kodi, it would be difficult to implement at the time it was built, but there may be options available now. If filtering is done real-time during playback there is no need to do any processing on the soundtrack. This does however require some sort of analysis to ensure no clipping.
  13. Kvalsvoll

    The Bass EQ for Movies Thread

    @SME, the graph files would be used by those who do not have the .mkv file, and thus have no intention of doing eq on individual channels. Or by someone like me, when I just want to watch a movie using the bass-system dsp to do a simpler bass-eq, not wanting to spend hours to do the remaster process. For this, the bass-managed graph will do just fine, and when applying proper eq in dsp on the bass-system there will not be problems with internal clipping. @3ll3d00d, ffmpeg can do the necessary signal processing, filters are available. I just took a brief look into what is in there, and I believe ffmpeg also can handle the remux. The process of applying the filters to the .mkv should be automated, so that you run this as a command after creating all filters and adjustments. This will take some time, because all channels must be extracted, processed and then put together into one new track, at full sample rate, which is then at last remuxed into the original .mkv so that you end up with an additional bass-eq track. Using flac encoding is a good idea here, saves space and bandwidth. This can be done.
  14. Kvalsvoll

    The Bass EQ for Movies Thread

    @3ll3d00d, signal processing and remux would require some effort. First, all tracks must be extracted at original sample rate, then apply signal processing for the filters, and finish by muxing the new beq remaster track together with the original .mkv. Extract and remux is not difficult, you already use ffmpeg to extract, perhaps look at mkvtoolnix for the remux. Signal processing I am not sure of, would start to look at ffmpeg to see what functionality is available, also search for open-source projects. Graph files of movies would be very beneficial for most users, as they will not have access to the movie as a .mkv file, but could still use the beqdesigner if graph files are available. This also prevent problems with copyright issues, which would be an issue if it was necessary to make the sound track file available. Lots of movies have already been analyzed, and if the graphs were accessible in some kind of library, people could find them there, and use beqdesigner with no need to extract audio files.
  15. Kvalsvoll

    The Bass EQ for Movies Thread

    One advice on bass-eq: Bass-eq is not about correcting the frequency response of a movie sound track so that the spectral distribution becomes flat. Bass-eq is about lifting up the filtered ulf so that the level is restored back to what it was before filtering. This can only be done by guessing how the spectrum should look like, and apply appropriate filters. There will be peaks and dips and deviations from a flat curve, depends on what sounds are present in the sound track, and how they are made. So a bass-eq correction should not look like the eq one could do on a bass-system, where peaks are cut down and frequency ranges with too high or too low level is corrected. Though on some movies there can be improvements by cutting a few dB in the 30-40hz range, and to decide what works best, you have to listen to it and correct accordingly. ( @SME also speaks about this in his post above.)