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  1. 6 likes
    I just attached the plans to the first post for anyone that wants them. I've had 3 or 4 other people request these plans over in Europe. Hopefully there will be some more documented builds coming up.
  2. 3 likes
    Gjallarhorn 2 plans. GH 2 print.pdf GH 2 print.DXF
  3. 3 likes
    Othorn files. OTHORN print AUTOCAD 2000.DXF OTHORN DXF scale print.pdf
  4. 3 likes
    Back from the dead... I finally have the last 4 drivers for the second cab and have been slowly installing them. I should hopefully have the 2nd one ready to plug in late tonight. I am not looking forward to moving everything out and putting these back in the corners. I have to pull the first one back out of the corner, pull the hatches and a couple drivers and rewire it the same as the second too. Lift with the legs...
  5. 2 likes
    Well it's his problem when he has his mixers crank effects up so far that they become compressed, honky, clipped messes (DKR, Interstellar) with heavily filtered LFE's.
  6. 2 likes
    Thanks for the links and for the tips. Unfortunately, the majority of posted images were Photobucketed, as you say. I did look at a few images. Because most of the measurements were of the "Edge of Tomorrow" opener, which is a very different kind of signal, I decided to look at the vibration vs. time data instead. I can post a screen-shot of that measurement it if people want me to, but I think it's rather boring. It looks quite a bit like pink noise. Recall that the test sample is pink noise which is filtered fairly steeply at the top between 40-50 Hz and played at around 97 dBZ RMS, according to my mic, which is not calibrated below 5 Hz. It looks like my RMS vibration values came out to roughly 0.0055 in the X and Y axes and 0.025 in the Z axis. With a little math, I can extrapolate this to the higher levels that would likely present with peak effects, say 15-20 dB hotter, which is a factor between roughly 5 and 10 for a "level quantity" like acceleration. So with pink noise at a more spirited level, I could maybe push over 0.25g on the *really hot* effects. I believe that on something like a PvA, the pink noise response should rise toward the bottom by about 3 dB/octave, which is not unusual for some of the stuff that's bottom heavier. Comparing these extrapolated results to what I see in the thread, it seems I'm coming out on the low end of the results. Unfortunately, very few people are measuring or reporting SPL along with their vibration response, so it's hard to tell just how hot people are running things on that end Furthermore, The "Edge of Tomorrow" opener is not a very useful test signal, and it's most of what I could find on the early pages. While each fundamental frequency in the sequence hits a different part of the deep bass / ULF spectrum, the overall coverage of the spectrum is extremely narrow. I'm thinking that tomorrow I will try measuring a slow sine sweep. Unfortunately, without getting at the raw data and analyzing it, I won't get the kind of noise rejection that sine sweep impulse response measurements benefit from. I could always buy the app and whatnot, but if I'm going to spend money, I'd rather do it right. For now it's not a priority. I'm not especially bothered by the fact that my readings appear to be low. I see a lot of enthusiasm in the thread about gains made by doing stuff like mis-aligning the timing of the subs and compromising frequency response. And of course, there's the interest paid to (alleged) differences between ported and sealed subs. But I have to ask: Is this what we really want? Is tactile response so important that aspects of performance related to frequency response should be compromised? This is an especially important question when one considers that a lot of these responses may be quite ugly and full or resonances. Mine sure is in the low teens. This makes for a pretty lo-fi experience, all things considered. Another thing is that, to the extent the floor is shaking, it's likely the walls are shaking too. That can add a lot of unwanted noise to the bass experience and really kill the immersion. That's something that I believe improved with my multi-seat EQ optimization, and I wouldn't be surprised if my EQ optimization reduced my couch vibrations too. Is that really a bad thing? I happen to really how it sounds, and I can clearly hear ULF well into the low teens when it's above hearing threshold levels. I also love the very tight transient response and "bottomless" quality of the sound on un-ftilered tracks. And if the level is up there, I feel plenty of tactile sensation. It's just rather different from couch shake. On another note, I definitely think I experienced more shaking with the old Hsu subs, which were ported and tuned to 18 Hz or so. However, I noticed this even more at higher frequencies, like 25-50 Hz, above which the near-ish field MBMs took over. I seriously doubt that the fact that they were ported had anything to do with the higher frequency sensations. My strongest suspicious is that this shaking was caused by mechanical vibrations of the cabinet. The D.O. configuration eliminated those and thus "cleaned up" a whole lot of floor vibration. It took some time to get used to less shaking, and I did opt to boost the subs a bit more than before. But I'm OK with the change. To me, having a more vibrationally inert presentation is more accurate and realistic. In other news, I can add "The Incredible Hulk" to the list of movies that I *cannot* play at my preferred listening level with my system as it is calibrated. The university scene played just fine, and was actually a lot of fun. The cop car smash scene did not work out so well. The big hit at the end (when there's practically nothing left of the car) is enough to light up the orange clip lights, at only "-9" on the MV. My preferred level would be more like "-5". For all the effort I went through to get as much ULF as possible out of this system, it's still not enough for these most demanding scenes. When I upgrade the amp power source to 240V, I should get another 3 dB of headroom, but I doubt it will be very useful, being that the drivers are probably close to their clean max excursion. What disappointed me more is that I honestly can't say whether I the perceived low end of that content. Was that effect at 8 Hz? If it was there, it was very subtle. Maybe if I paid attention, I could feel my hair move or something. This is something I'll want to double blind test later along with ULF on more transient sounds. It may be that this content just isn't hot enough to perceive without the help of floor/couch motion, and clearly, I have very little of that below 11 Hz. This would then imply that the content under 10 Hz is of no interest in an *accurate* presentation. The only way you'll know it's there is if the floor or furniture is vibrating to it or if the subs are distorting enough to enhance the phantom fundamental. In a studio with concrete floors and no motion actuators, it may not be perceived at all. This does make me seriously consider Crowson's. If the goal is to make the couch shake, I'd rather use the right tool for the job. Although, this kind of upgrade will be a fair ways off. Unfortunately, I'd need another Motu unit for more output channels. And then I have to worry about my racks getting cramped with an extra amp or two. My sofa is a 5 piece sectional, which is rather inconvenient, not to mention expensive. If I used Crowsons, I think I would low pass them at around 20 Hz. As for the subs, I guess it all depends on how I feel after double blind testing. I have a lot of options there. I can EQ things less aggressively down low. I can use less boost below some frequency. I can also try to implement some kind of frequency-selective limiting, though this gets tricky with ULF if I want to avoid unnecessary phase shift. Another option I might consider is a bit more of a ramp in the ULF, which I can probably get away with if I ramp down or high pass below 10 Hz. There are still a lot of possibilities to explore.
  7. 1 like
    Hey Kyle, I noticed that the forum software went through a big update. I've noticed a few issues since then: Several links, including those posted to the front page of the "Low Frequency Content Thread" are broken. Looking more closely, I see at least two types of links there: http://data-bass.ipbhost.com/index.php?/topic/12-the-low-frequency-content-thread-films-games-music-etc/?p=269 http://data-bass.ipbhost.com/index.php?/topic/12-the-low-frequency-content-thread-films-games-music-etc/page-17#entry465 The latter type is broken, presumably because of a change in pagination of the content. It looks like the latter type can be fixed by changing it to the earlier form, i.e. /page-17#entry465 ==> /?p=465 I think these could be changed all at once using a regex. If you're not sure how to do this, I can give it a stab if you can send me the raw content of that post. Several PvA graph are broken. I don't know what's going on yet, but some are broken and some are not. The post Likes are now anonymized, which is weird. Perhaps this is an optional setting that can be tweaked? These are the things I've noticed so far. If anyone else notices issues, please feel free to add a post to this thread.
  8. 1 like
    Just noticed that. I definitely liked the link directly to the main site!
  9. 1 like
    This is how Powersoft K series amps operate all of the time. Those guys are smart so you'd have to assume they did that for a reason. This likely only shows up as a measureable improvement when the power draw becomes large and starts to sag the AC line. More useful for pro sound apps where you might have many amps driven hard on one circuit and/or the circuit isn't great to begin with like a generator, etc. Many years ago Ivan Beaver from Danley Sound showed me how to do this at a GTG. Flip polarity of one input channel in the amp and re-flip/correct at the speaker wiring to bring back in phase. Worked pretty good with a Crown CE4000.
  10. 1 like
    Ok. That makes more sense. That sounds similar to my old room over a crawlspace. Little measured SPL at 12Hz but the floor was violently shaking.
  11. 1 like
    This thread was hosed by Photobucket. Sometime this week I'll fix all the pictures and links.
  12. 1 like
    Etymotics to the rescue! I need to find a true IMAX to see it in, though. JSS
  13. 1 like
    Do you mean the notch at 11 Hz or the octave wide dip across the 7-14 Hz region? At the 11 Hz notch, things do shake pretty bad. I probably mentioned already, but when I probe that notch using sine waves, SPL in the low 100s dB is enough to cause some serious ceiling shaking and causes my dining room lamp to literally bounce up and down and start swinging. I fear that much more output in the narrow vicinity of that frequency will damage something, so I leave the notch there. As for the broader dip though, there isn't much happening other than at the notch and a little bit above it. BTW, my house is about 48 feet in length, which suggests that my primary "room mode" should fall right at about 12 Hz. If you look at my raw measurements, the red traces are closer to the end of the house and so should theoretically have more output than the blue traces. Likewise, the left sub is closer to the house end so should measure hotter overall. In both cases, the opposite is actually true. No, I don't mean to say that tactile sensation is exclusive to hi-fidelity at all. I was referring to couch shaking specifically, which is what these vibsensor tests are measuring. In my experience, tactile sensation is multi-dimensional. The couch/floor shaking is one dimension. The interaction of sound in the air with the body directly is another dimension. I believe these sensations feel quite distinct from one another. Typical studios probably have inert floors (e.g., concrete under the flooring material). Engineers are even known to go out of their way to reduce floor vibrations in their studios, at least at higher frequencies. If the shaking is too strong, there is a tendency for the those sensations to overwhelm and mask the sensations that are felt from the sound directly. The shaking response is also a lot less likely to be flat when SPL response is, and this could cause mixers to misjudge what's going on in the mix. By my subjective assessment, my old Hsu subs shook things a lot more, and I believe that the shaking was so strong below 30 Hz or so that it overwhelmed most of the direct tactile sensation there. Anyway, I don't mean to say that shaking sensations are "wrong". For some kinds of effects like earthquakes, shaking probably *is* the appropriate sensation. With something like thunder though, a lot of shaking is probably a lot less realistic, especially if the depicted scene is outside. I think it would be interesting if the standards provisioned an extra "SEX" (shaking effects) track, kind of like LFE, that's intended to be sent directly to tactile transducers (TTs). This would give sound designers a way to express the intent. For example, a thunder sound effect could be routed exclusively to the subs, and an earthquake effect could be routed exclusively to the TTs. It's a shame that we can't even get the industry to acknowledge a role for ULF in any capacity, even though many cinemas are now installing shakers in their seats And yeah. I guess my experience is more evidence that content under 10 Hz is not especially relevant in terms of pure sound. And furthermore, my experience should serve as a caution to those with suspended floors who would expect to feel single digits content if they install sealed subs. Clearly, a suspended floor offers no such guarantee. It all depends on the resonances. And since a response supported by resonances is not going to be high-fidelity, it may make most sense to recommend 10 Hz as the lower limit for subs and leave the single digits for tactile transducers. It'll be very interesting, when I get around to it, to find out whether I or anyone can identify the existence of single digits content from my subs in double blind testing. Edit: I should mention that I really like what I experience with good dynamic music BDs. The bass is a lot like listening outdoors, including the nice sharp punch from the kick drum. Breathing feels kind of weird with these sensations. And this is with the sub out channels barely getting above the "-48 dB" line on my Motu. The thing is, I don't think a couch vibration measurement will reveal this "punch" dimension of tactile experience, which also happens to depend a lot more on frequencies between 50 and a few hundred Hz.
  14. 1 like
    Since you want to listen a lil louder, SME... just lower the boost by the number of dB you want. Really doesn't matter since you say you couldn't appreciate the single digits as much as you hoped you would. Open up more headroom where you want it!
  15. 1 like
    I no longer boost my subs down low chasing a flat freq response. I just use the crowsons for the <10Hz stuff (and sometimes significant amounts above 10Hz, esp at lower SPL listening). JSS
  16. 1 like
    I don't think it's fair to characterise those threads as maximum vibration chasing. Obviously there are some people who do that, just as there are people who chase extreme SPL, but mostly it's about finding out how it responds & what feels right/good. There seems a lot of variation on that point, or more specifically, the way people describe what they like seems to vary a lot. It's all about balance in the end.
  17. 1 like
    I quoted the parts I agree with most. The first paragraph is the same type of thing I have been thinking about the trend of maximum vibration chasing. I don't doubt that having a good FR, lots of SPL AND vibration, are all important aspects to consider. Some of what seems to be being suggested in those threads (That you mentioned) seems like very bad advice to me. I remember someone suggested using smaller vents to increase their particle velocity. With the amount of boost you are using Hulk will be a difficult load on your amps and drivers for sure. The cop car punch is a short but tough signal. I think a 7 or 8Hz fundamental is about right. Without tactile vibration to help transfer the <12-15Hz content it is barely there in my experience. Below 10Hz it's pretty uneventful without a major structural vibration to go with it. It makes all the difference. 32hz at 115dB is very apparent, you feel it and it is loud. 16Hz at 115dB is much less obvious but with that kind of level you can sort of hear it and still feel it. Somewhere around 12-13Hz for me it becomes hard to hear much of anything anymore unless it is strong as hell and even then it's just an odd modulation on everything else. Pressure waves like a rapid on/off switch on the ears. I've heard 12-13Hz at 115dB or so outdoors with test tones and it was subtle. It was like the rest of the background sounds I was hearing were coming from behind a fan. My current HT room is very solid. I get a ton of gain and SPL but very little shake other than from the ceiling. The single digit stuff is an occasional odd pressure sensation if it is very loud and not masked by other content and that's about it. I don't think I would miss much in my room if I only got down to the 10-15Hz range. I expected that you would have a ton of vibration near your notch in the teens. I'm surprised that you don't show more. If the energy isn't being exchanged there where is it going? That should be too low of a frequency for it to be a null induced by the room dimensions.
  18. 1 like
    Hello from The Harbottle Audio Co. We would like to take a minute to tell all of you good people that we are an authorized dealer for Funk Audio components and Focusworks Audio drivers. These drivers and amps that are gaining rapid awareness are now available to the public. Keep in touch for special offers and promotions. You can find us at www.harbottleaudio.com
  19. 1 like
    Available by July 15th! Man18 DIY subwoofer kits. http://www.harbottleaudio.com/ We are also searching for any interest in a group buy for the UH21v1 w/2.4kW x1M3 plate amp. Please fill out the form below to voice your enthusiasm for this offer! http://www.harbottleaudio.com/special-offers.html
  20. 1 like
    Does DB / @Ricci get commission? HA. not from me. He might have to talk to Nathan Funk about that. but seriously though, data-bass testing is by far the most comprehensive. i'd be a dummy if i didn't point to this site. I've sat back in awe of what you guys can do, know, and understand for about 7 years now, and Im just feeling like Im getting it nailed down. Then i visit a facebook group and suddenly im a genius!
  21. 1 like
    A few screen caps of the movie watched late last night at a low-ish volume level: Getting Power Up There? Turn Rig: Negative Pressure Test: Pipe Burst 1: Check out the 10 Hz hot spot in this chopper scene. Not as massive as some movies but it is still there:
  22. 1 like
    Focusworks GUJ21v1 is now available. There are a couple of drivers in stock ready for delivery. These were used for testing by DB and Focusworks. Data-Bass test results should be coming along soon as well.
  23. 1 like
    It does over half its rated power @ 5 Hz. Just wow!
  24. 1 like
    For the SP2-12000 testing, a fluorescent light near my work bench was flickering, so I wonder if I had some voltage drop. I was expecting the 12k to hold full power for closer to 4 seconds, but maybe my 240v 30A circuit is holding it back? Also, just in case I wasn't very clear, that's with both channels running equally but I'm only measuring the voltage off a single channel. So all in all that amp was outputting a total of 12,000w RMS for 2.5 seconds, which is really close to factory specs. That also means for 2.5 seconds the power supplies were outputting over 110A combined! For the last 4.5 seconds they were outputting over 70A, and I'm sure well before that point the capacitors were completely drained.
  25. 1 like
    SpeakerPower SP2-12000 - Both channels driven* *Both channels were driven equally but the measurements below are only from a single channel. The SP2-12000 can output these numbers below per channel (x2). Summary of the 12 second 20hz sine wave test: This was run with both channels driven like the CEA-2010 burst testing. The SP2-12000 maintained 308Vpp / 5,927w RMS for 2.5 seconds and then over the next second decreased to 228Vpp / 3,248w RMS and maintained that for another 2 seconds. It then gradually decreased again to 206Vpp / 2,651w RMS and held that for 4.5 seconds until the end of the 12 second test. At the end of the 12 seconds the amp was still cold to the touch and the fans were idle.
  26. 1 like
    Here is what the manufacturers recommend. Sealed enclosure 0.7 Q, with recommended power to reach Xmax. GUJ18V1 150L 2000 watts TSAD18V1-R 100L 2000 watts (based on preliminary specs, subject to change) GUJ21V1 275L 2000 watts TSAD21V1 250L 1500 watts (based on preliminary specs, subject to change)
  27. 1 like
    That is an excellent question and it will be answered. In order to give everyone a comprehensive view of these drivers and how they compare, we will be compiling recommended enclosure designs and sizes over the next few days. Keep an eye on our website and this thread for details. Thank you. The H.A.C.
  28. 1 like