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Showing content with the highest reputation since 08/21/2018 in all areas

  1. 5 points
    Bolserst is a long time contributing member over at DIYAudio forums. He has developed this spreadsheet that will take an impedance measurement and calculate the complex inductance of a driver. David McBean the author of HornResponse has added the capability to simulate using this data into HR. This is a much more accurate way to simulate and design speakers and subs. In short if you are designing bass systems using modern, high power, long throw drivers and you are not accounting for complex inductance in your modeling; The models are probably not representative of what you would be building. Previously you would need to purchase costly software in order to derive and simulate using these parameters, or figure out a way to roll your own way. The spreadsheet imports a text file of an impedance measurement and calculates the complex inductance specs. Additionally if you have an added mass or Vas (Known air volume) impedance measurement you can also import it and the spreadsheet will calculate all driver parameters needed for modeling. A driver file can then be exported for use in HR. Semi-Le_Calc_V2.zip
  2. 4 points
    Finally some pics of the assembly process. The MW's of @lilmike are finished on Wednesday.
  3. 4 points
    Going back to my issue with the drivers in electrical series, I can say there is absolutely no difference between them linked like that or parallel. All my tests and measurements showed me nothing changes, a small voltage difference is present, but only 1-2 V at 60 V sines.
  4. 4 points
    Agreed...There have always been a lot of hang ups with terminology in audio circles and fixation on defining things by a strict set of rules. In order to be an IB the back volume must equal at least 10X VAS...Waveguide vs horn etc... I consider the Skhorn a hybrid 6th order design. Fun fact...Skhorn is pronounced like the word scorn and I gave it that name because after exploring all the options I could think of attempting to do a horn of some type, I ended up not doing a horn at all. No matter how much I wanted to, and I really wanted to make a horn at first, I simply could not make a horn this size that would perform like this cab. After giving up and scrapping all the horn ideas for a hybrid 6th order BP I called it Skhorn as a middle finger to bass horns in general. Most people think it's called that because it's some kind of horn LOL.
  5. 4 points
    fwiw this release can show the bass managed result of a set of filtered channels in the app, updates live as you change filters and reports on headroom available - https://github.com/3ll3d00d/beqdesigner/releases/tag/0.5.0 I recommend using a decimated track if you want this to perform acceptably so that means it isn't a perfect simulation, close enough though for this purpose IMO
  6. 3 points
    git clone git@github.com:3ll3d00d/beqdesigner.git cd beqdesigner git checkout 0.0.2-beta.2 python3 -m venv beq . beq/bin/activate pip install numpy colorcet scipy qtpy qtawesome pyqt5 matplotlib ffmpeg-python soundfile resampy cd src/main/python # you also need ffmpeg and libsndfile1 installed, e.g. sudo apt install ffmpeg libsndfile1 then open mpl.py in a text editor and change the following change for k, v in cc.cm_n.items(): to for k, v in cc.cm.items(): (this is due to some lib having an older version in pypi vs conda, it is fixed in next release) then python3 app.py and you should find it fires up I'll get round to packaging it properly for linux soon enough next release will properly support pre BM BEQ btw, will publish that tomorrow hopefully I run Debian Testing here and it seems ok, haven't tested it extensively though so let me know if problems, will get round to testing it properly on linux at some point. The same approach has also been used on the mac too btw.
  7. 3 points
    FWIW I decided to knock up an little ui to make experimenting with BEQ easier (so it can extract audio using ffmpeg & show the results of adding assorted filters, comparing tracks) hence it removes the need to faff around with speclab). An early release (windows only atm as I'm away from my linux boxes) is available at https://github.com/3ll3d00d/beqdesigner/releases/tag/0.0.1-alpha.2 Here's a pick to illustrate https://imgur.com/a/KgfaxOJ This is still a fairly early build (and the exe is a bit massive) but it seems to be usable so thought I'd share it. The readme at github has some of the things left to do and some bugs. One thing not mentioned there is being able to apply different filter sets to different signals. EDIT: I replaced the exe with something that should display errors if you start it from a console (as someone on avs reported it didn't work for them) EDIT2: possible workaround in https://www.avsforum.com/forum/113-subwoofers-bass-transducers/2995212-bass-eq-fil-turd-movies.html#post56692822
  8. 2 points
    I have heard the TH-50 way back what must've been a decade ago now...It was quite powerful in the basement of the home that we demo'd it in. Ivan also brought a Danley CS-30 and a THspud from what I recall. The TH-50 uses a beastly 15" driver (MTX 9515-44) and it's a huge cab but it does deliver the goods. Since the thread is about the Skhorn perhaps we should move discussion to a build thread on the Microwrecker. LilMike is someone I've talked to for years and met before. He's a good guy and he lurks around here, so if you have questions don't hesitate to ask him.
  9. 2 points
    TH's have a harmonic spike in what is commonly considered their bandwidth which can end up causing issues. If the TH is tuned low it moves the placement of this spike down in frequency until it can end up in the critical bandwidth you want to use the sub in. Bass guitar and kick drum range...As the TH becomes more and more undersized it exaggerates the spike in response even more. The more the tuning is lowered the greater the TH will be undersized effectively. There are tricks that can be done with the design to minimize this harmonic spike and a very well damped driver helps somewhat. You can also attempt to address it with EQ. However if it is bad enough it will always be audible. In my opinion TH's work the best when only extending to 25-30Hz at the lowest due to this. This allows you to keep that harmonic above 100Hz and above the usual low pass for the sub. This is why I quit pursuing big TH's that extend deeply. Other designs can be made to sound excellent over a wider range much easier. Sealed, IB, ported, FLH, or BP variants. In my opinion for HT powerful headroom down to the 15-16Hz range gets most of the content. It's greatly diminishing returns below that point. For music I consider 25-30Hz the minimum for good reproduction without missing out on the "heavy" notes.
  10. 2 points
    @3ll3d00dI need to download this and try it out. Thanks for developing this tool! @SME RP1 BEQ is currently my favorite track. The movie is not bad, either. You can watch it many times just looking for more nostalgic references. JSS
  11. 2 points
    Hey Mark. Sure...I pointed out it is a 6th order variant the first time I posted about these a few years ago. Personally I refer to these as BPH's due to the large expanding slot section, where as a traditional vented 6th order would have a chamber and a port. These lack a traditional chamber or vent on one side of the cones but I don't really care what label is put on it. BP6/BPH etc...Results are what matter to me.
  12. 2 points
    https://github.com/3ll3d00d/beqdesigner/releases/tag/0.5.2 contains some enhancements to the built in bass management sim which means you'll get a more accurate idea of whether it is going to clip or not after filtering & also lets you more easily see the impact of BEQ on the full track (via the spectrum comparison view). If anyone has any other suggestions for how to make this more useable then feel free to raise them (otherwise it's just whatever I think makes sense based on me using it to try out BEQ for tracks).
  13. 2 points
    Mr. Ricci, can you design me a ported box for the SI HS-24 with no more than 8 cu.ft. of enclosure volume? And can you tune the port to 12Hz please? You’re the bestest! Thanks Josh. Happy Holidays guys! Thanks for hosting such a magnificent and informative site!
  14. 2 points
  15. 2 points
    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.
  16. 2 points
    FWIW, I liked TLJ as a film a lot more after the second watch. It's definitely flawed, but what SW film isn't? Yes! Because the channel architecture includes the LFE channel for extra bass headroom, any film mixer that wants to use LFE in the mix must effectively use some kind of bass management when creating it. Microphones and synthesizers don't tend to spit out separate LFE tracks, and I doubt the sound designers deliver content with separate LFE either. Even if they did, it wouldn't allow optimal budgeting of headroom in the mix, so basically it comes down to the mixer to figure out how to distribute the sub bass between the different channels of the mix. I'm sure many different strategies are employed including the wacky filtering schemes seen in TLJ and many other movies. I wouldn't be surprised if a lot of the bass that appears to have been filtered from the surrounds was simply re-routed to LFE instead. This is probably why almost every one of the BEQs developed by @maxmercy uses quite different filters on each channel, and why I believe this approach is usually necessary for good BEQ sound quality. Even then, it's probably not possible to fix everything. The bass management on the production side may be applying very different filters to sound that is redirected from each mains channel to LFE. For example with TLJ, it's possible that the 40-60 Hz part of the LFE channel contains a lot more bass that goes with sounds in the surround channels than screen channels, but below 40 Hz, it's a more even mix of screens and surrounds. So any adjustments made to LFE could have different effects on the surrounds vs. the mains. Lastly, we need to remind ourselves that bass management on playback systems has a lot of problems too. Probably very few systems out there have neutral sounding bass for sounds on all 7.1+ channels of a soundtrack because of sub crossover phase issues. The more savvy home theater people know to optimize sub delay for best sub crossover response, which makes a *huge* difference, but this is only possible on one channel (i.e. the center channel for movie optimization) or some weighted sum (i.e. left+right for music optimization). How many people here or anywhere have good response in the sub XO region on their surround and overhead channels? Yes, those channels do get used for bass, and they get used a lot more now because immersive formats for the cinema specify bass management for the surrounds. I personally have the capability to optimize bass management completely and separately for each mains channel and for LFE, which is itself optimized to blend best with simultaneous content in the center channel. IMO, this should be a minimum requirement for a "high performance" home theate, but it's not possible to do this with any standard home theater processors I know of (without spending 6 figures $ at least). I doubt very many "Atmos at home" production systems have that capability, which means they aren't hearing the bass right on their own soundtracks. (Sadly, I wouldn't be surprised if many of these don't even have the sub distance optimized for best center channel response.) At least Atmos in the cinema specifies that surround and overhead channels be bass managed to separate "surround subs" located closer to the back of the room, which probably helps a lot, but Atmos for home is still essentially a 7.1+ format.
  17. 2 points
    So I watched "Black Panther" finally. I played the BD 7.1 at "-1" (!), and my Denon did not indicate any dialnorm compensation was applied. I have to agree that this soundtrack has serious deficiencies caused by excessive and/or mis-configured dynamics processing. It was bad. It seemed worse than the dynamics of old analog TV. Not only were macro-dynamics largely eliminated but the compressor attack seemed to act immediately and aggressively on transiently loud sounds such as gun shots. IMO, the consequences were wide and substantially degrading to the viewing experience. The experience was passive and uninvolving. The on-screen action and actors seemed trivial and insignificant. It wasn't just special effects that were harm but also the score, dialog, ambiance, etc. The scoring involving live acoustic instruments (vs. the pop / hip-hop style music) sounded completely unnatural and irritating to listen to because of the pumping effects. In one scene, dialog alternated between a few key characters and a large crowd, both of which were rendered equally loud but of course this made the crowd sound very whimpy, and the aggressive compression really muddied their voices together. It really broke the immersion. The acting seemed quite forced throughout the movie, but I could also tell that the dialog completely lacked the dynamics which may play a big part in conveying passion and emotion. The weird thing is that even if this aggressive compression was done on purpose, perhaps to optimize for hand-held devices in high noise environments, the level of the track was extremely low. I basically had to turn things up to cinema reference level to get sound that still wasn't that loud. That's a huge amount of gain as far as hand-helds go. On most if not all such devices, this track would be difficult to hear even with the volume at max. Oddly enough though, it had some decent bass in a few places, particularly in some of the quieter scenes where there wasn't as much mid/high frequency content to compete against. The tonal balance was actually quite nice, and I experienced a surprising amount of ULF with rather strong tactile effect. A lot of ULF just makes the windows rattle and maybe shakes the floor a bit, but this was felt quite strongly in the chest area. I believe the presence of higher harmonic frequencies with good balance all the way up essential for this sensation. The ULF itself makes the least contribution to the sensation but helps fill it out and make it more real and present. It's just too bad that the good bass was totally missing from a lot of transient effects. Anyway, I have a hard time believing that the problems with this soundtrack were intentional. It's certainly possible that people misjudged the quality of the track because they were too tired or something. Or maybe people were just rushed. Maybe mistakes were made that were to difficult to correct. Still, this is bad enough that I think it'd be reasonable to ask for a correction and recall. I didn't buy this film, and have no interest in doing so after what I experienced. Still, I hope this isn't an example of Disney's future. I thought some of the Pixar films like "Coco", "Inside Out", and "Finding Dory" were fine as far as dynamics were concerned. They might have been pulled back a bit compared to typical cinema tracks, but I kind of expect that with kids movies. And anyway they still were *way more dynamic* than "Black Panther". Edit: Just to clarify with my opinions regard to discussion in some of the recent posts: I thought "Black Panther" and "The Last Jedi" were kind of at opposite ends of sound quality and performance. TLJ had very nice dynamics, it just needs high master volume to get things nice and loud. BP is about the same average loudness as TLJ was (7.1 at least) but had practically no dynamics at all, for which there's no real cure. BP really looks like a QC error as does the Thor:Ragnorok Atmos track which apparent has severe compression but only for the first half. I hope it's just these two, but I guess I'll find out how Avengers 3 is.
  18. 2 points
    @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.
  19. 2 points
    Apologies for taking so long to give a review. I *finally* watched this tonight! I just kept putting it off because I've been working so hard on new/improved treble optimization. I'm still not done and was thinking I'd save it for when I'm "done", but my wife got tired me of putting it off. I'm glad I listened to her. I think this is my new favorite soundtrack, and the BEQ takes it to 110%. I watched it (BD/Atmos soundtrack) at around "-5" on the MV. (I forgot to check to see if there was any dialnorm modification to that, so it might have been less). My system is configured with a pretty generous house curve (up to 10-12 dB "hot"). Pretty much all of the bass sounded full bandwidth, and the frequency balance was excellent. At no point did the low stuff overwhelm the mid-bass nor any of the rest of the spectrum. The sound effects were very cohesive from top to bottom, and the tactile sensations were detailed, articulate and at times brutal. There were multiple jaw-drop "jump out of my seat" moments where things just went BOOM spectacularly. The surround work in this mix was a big part of experience as well. What can I say? This this a superb demo piece: for my bass capability, my overall sound capability, for BEQ as a technique, for superb sound design, etc. It is state-of-the-art. A big thanks to @maxmercy for taking the time to do this!
  20. 2 points
    latest builds have a split screen before/after beq spectrogram view as well as a way to check the headroom in the waveform pre/post BEQ which you may find useful (and colourful!)
  21. 2 points
    Just a small update: My horn sub project in the form of @lilmike's MicroWrecker tapped horn has been initiated. I've ordered two B&C 15TBX100 15" drivers for a pair of Micro's, so plenty of headroom should be available. They'll be build in 11-layer Russian birch ply by a cabinet maker I know. Amp and DSP solution as of yet not determined.. /Mikael
  22. 2 points
    Another issue that may be a lot more challenging to address is proper support for the lower-end MiniDSP devices, the 2x4 and 2x4 balanced, which use 56-bit fixed point processing instead of floating point. This causes errors due to precision loss below 20-30 Hz, which become worse with decreasing frequency. These errors can be substantial even when using the MiniDSP in the mode that is optimized for low frequencies, without which any kind of ULF EQ is pretty much useless. I got bit by this problem pretty hard back when I used a MiniDSP 2x4 for in-room sub EQ. The errors are not small. Even with a floating point implementation, the precision of the floats may matter. (I haven't thoroughly tested it.) Processing the audio in 32-bit float format should be good enough, but the biquad coefficients and temporary variables may need to be double precision for sufficient ULF accuracy. My implementation does this. I don't know if the floating point MiniDSP units represent the biquad coefficients and temp variables as 64-bit or not. Likewise, I don't know how much precision the fixed point MiniDSP units use to represent the biquad coefficients. These are details that may need to ascertained by reverse engineering in order make tools like beqdesigner as accurate as possible. What about DSP built into amps? It's the same story there too, and each device may behave differently. (This is probably part of the reason many amps don't allow filters below 20 Hz.) These issues don't just affect beqdesigner but affect implementation of the BEQs posted in this thread too. It's just that the independent channel BEQs are designed to be implemented upstream of bass-management, which limits the devices that can be used to apply them to devices that probably have at least 32-bit float precision. Along these lines, it would probably be good to investigate ffmpeg to understand how it will process biquads. I took a look just now. It appears that the internal implementation supports 16-bit and 32-bit integers along with 32-bit and 64-bit float with coefficients always being represented using 64-bit float. The integer formats don't offer any headroom, and because each biquad is processed separately, clipping will occur immediately if any one biquad pushes the signal above full-scale, even if this excursion would have been canceled out by a later biquad. As such, it is crucial that ffmpeg be used in such a way that it uses floating processing internally, and of course, the result will only be accurate for the highest precision floating point DSPs.
  23. 2 points
    @SME, the interest for bass-eq is very, very low considering the huge impact on sound experience. One reason for that is that very few people actually has a sound system capable of reproducing full range with decent capacity and quality. One purpose of this thread was to create awareness, so that the producers deliver better, unfiltered sound in their movies. No bass-eq necessary. Only a few movies deliver that, even today it is rare to see a new release with full frequency range intact. The reason why is that they are clueless - they have no idea that anything is missing in their sound track. No producer would allow a filtered movie to be released if they knew their product could deliver a much better and more involving experience. Most people play the bd and have no option to change the sound track, the only option is to use eq in a dsp somewhere in the chain, and since all decent bass systems has a dsp, it is convenient to implement bass-eq on the bass-system. The drawback is that you can not do individual filtering of the channels. But compared to no bass-eq, this is a good and very useable alternative. I prefer to do individual corrections, because it is better, @maxmercy is very clear on this, he is the true bass-eq purist among us.
  24. 2 points
    There was a graph. Must have disappeared with the rest. I remember it graphed (and sounded/felt) well on my system. Thought the sound was pretty terrific actually. Nobody seems to like this movie though. I liked it well enough. Just wasn't the Prometheus sequel everyone wanted and expected.
  25. 2 points
    Now you hold on. Don’t mess with my fake sounds in space because I love said rumbles. And can you imagine how boring a space movie would be without sounds in space. Duh!
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