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Showing content with the highest reputation since 03/28/2012 in all areas

  1. 9 points
    Final quarter of 2017 update. JTR Speakers Captivator 212Pro results have just been posted. KRK Systems 12S2 subwoofer testing is done. Should be posted next. WW Speakers / Mark Seaton designed X21 cabinet loaded with B&C 21DS115-4 driver testing is done. Will be posted ASAP as well. This was tested with both vents open and with a vent plugged and with both the Powersoft K20 and an Inuke 3000DSP. That's 4 full measurement sets. We're killing a lot birds with one stone on this one. We have some information on the Inuke 3000DSP amp driving a real load. We have the 21DS115-4 driver itself, which a lot of people are interested in and lastly we have the X21 vented cabinet which is available off the shelf to fit a variety of pro 21's. I tell you the cab is built solid and of course Mark designed it well. It is not cheap but it certainly offers an easy button option. Next up is a set of 3 subwoofers from one of the commercial vendors. I'm not totally sure these will be public on the site since the MFG reserves the right to decide whether the results are public or private. I believe they will be though as so far their behavior appears to be well designed. And...After that...I have a couple of cabs from a pro audio company that will be on deck. Not sure these will be public yet either but I suspect so. I'm trying to get this all tested and posted by the end of the year. That's the goal. I have more DIY type driver tests sitting in the wings too.
  2. 7 points
    Update to powering the RF 19's. The 8 sealed in the HT will now be getting a pair of SP2-12000's. Each 6k module power 2 1ohm T3S1-19 drivers in series in a dual opposed sealed cab. This switch is mostly because the SP amps have less fan noise than the K20's. Also they have slightly better extension below 10Hz. The K20's are going to the band spot to power the MAUL's. Fan noise doesn't matter there. Each MAUL has 4 T3S1-19's wired in series for a 4ohm nominal load and will see a whole bridged K20. Yay headroom... Got power?
  3. 6 points
    I've got a couple of pro woofers on hand for 2018 so far. I need to do some more testing with the 21DS115-4, but I also have a JBL 2269H 18 and 2 18Sound 21's the 21NLW9601 and 21ID. I also have a couple of vented pro subs I didn't get to in 2017. Even more JTR Speakers testing is on the schedule for when spring gets here.
  4. 6 points
    Kong: Skull Island (Dolby ATMOS) Level - 4 Stars (111.38dB composite) Extension - 5 Stars (1Hz) Dynamics - 5 Stars (28.84dB) Execution - TBD Overall - TBD Notes - This film delivers bass in spades, especially in the shake-and-move-stuff wheelhouse range of 12-25Hz. Clipping analysis shows flat tops in nearly every channel, Center is most egregious, but all the clipping appears to have rounded edges as if some sort of limiting was put in place like Pixels, so not completely objectionable, like Tron:Legacy clipping was. LFE channel clips with sharp corners, but low-pass filtering will smooth them out. Better movie than anticipated, but it almost always seems that way when you expect nothing from a film. Good surround use, good soundtrack. BEQ should make this a structure-endangerer. JSS
  5. 6 points
    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.
  6. 6 points
    Othorn files. OTHORN print AUTOCAD 2000.DXF OTHORN DXF scale print.pdf
  7. 5 points
    I've mentioned it a few times before. A pair of JBL 4675C's. The 2226H drivers out of the double 15" (4508A) bottoms I sold off and replaced with AE TD15M-4 drivers with the Apollo upgrade. They are wired in series. The big 2360A "butt" lenses still have the 2446H CD's on them. Those sit on top of the MAUL's. It is a tri-amplified stereo system run from a Peavey mixer into a DCX2496 which provides processing and routing to the amps. The current amps are a 20 year old Mackie M1400i on the 2446H drivers (Run from about 600Hz up.), a Crest 8002 powers the TD15M's which run about 80-600Hz roughly and a single SP2-12000 currently has a MAUL on each channel running <80Hz. There's no surround sound and I never replaced the old projector after it died a few years back so there is no video right now either. It's just a mammoth stereo or PA as needed. It's nothing special but does the job. Eventually I planned to swap out the 2446H's for some BMS coax's or something Be and probably change the lenses too. Now I'm having thoughts of doing something different for the mids and highs entirely. Try to roll my own Synergy's or other design? Not sure what yet. I'll probably upgrade the amps first. Eventually I'll put my K20's one on each Maul and move to SP's at the house so I won't have to deal with fan noise at home anymore. I want to get a newer amp for the CD's. Only class AB or H for those though. I still don't think class D is quite as good for HF. I might just go with an A500. The power requirements on the CD's is almost nothing even at ear splitting levels. The room is in an old rundown, warehouse / factory, in a ghetto part of town. Myself and the other musicians I work with, have been renting there for 8 years or maybe more. The whole building just about is rented out to musicians, artists or people needing storage. The outdoor test spot is right out the backdoor. The room itself is a shotgun shaped space about 18ft x 15ft x 36ft. Roughly 10,000cu ft. I'm guesstimating and could be off some, since I've never actually measured it. Walls are double carpet hung over sheetmetal and studs with main building supports in there too. Flimsy and leaky as hell but the carpet hanging from the walls and the directivity of the horns actually keeps the space relatively dead. Every surface in the room except for the garage style door and the ceiling are covered in carpet. The room is over the basement level, but the floors are 4 to 5 inch thick cement type material over timbers, so it will shake some, but not easily like a suspended floor in a house. It takes a bit more energy. Ceiling is the same deal. Back wall is a brick interior wall with carpet over it. The back ground noise level is high usually of course. There are no placement options really as the room is jam packed with equipment of all sorts. It is not ideal and there are all sorts of acoustic and structural issues that color the sound. For one my drums usually sit directly in front of one side of the stack. Thankfully the horns are 8 or 9 ft off the floor well over top of them and the bass just goes around, so most of the sound ends up in the right place regardless. None of that matters really because that's not what it's about in there anyway.
  8. 4 points
    So after reading this thread over the past year and amazed and the technical depth and extreme attention to detail paid to the tuning of this system and going "man I really want to hear this!", I flew and went to check out this system. And boy what an amazing system to listen to! My mind was blown as I was amazed by one thing after the other. All the work put into getting the tonal balance of this speaker correct really paid off big time. The whole system just sounds really "correct", and the more I listen to it the more I'm amazed by it. I brought my Reference Mini's with me as a comparison, and there was a very obvious difference in sound quality. I thought my speakers sounded really great, but it sound noticeably "off" when compared to this system. The speakers had a fantastic amount of detail, and the transients are awesome! It felt like I'm listening to a pair of really good headphones (and few people realize how hard and impressive it is to achieve this), but I also get the enveloping sound that makes speaker listening so pleasurable. It's the best of both worlds. What's even more impressive is the bass. I don't think I've heard bass so tight and full sounding in a room, which is clearly due to the complex integration efforts of multiple subs and individual EQ's to get such flat bass over a large number of seats. The clarity and tightness is seriously impressive. Again, just like a headphone, and that is actually something I've never heard before from a subwoofer. It is straight up the best sounding bass I've heard in a room. Now when you also get the whole body physical sensation from bass, addictive is an understatement. One thing that is unforgettable and blew my mind is how great the speakers sound in the kitchen! I don't think SME has ever mentioned this, but it was indeed one of his goals. It was remarkable hearing a correct tonal balance with almost no treble roll off in a different room! I still can't believe this is achievable. It must be the combination of controlled directivity speakers and properly placed diffusers pulled this amazing magic trick of a feat. I've heard a lot of amazing home theaters, but this is the first time I heard imaging from surrounds. It was trippy to be able to pinpoint the location of the sound going across the rear stage. I really wish we watched an action movie and be able to so accurately track the position of the sound effects. This is even more impressive as I seem to clearly have less ability to hear imaging compared to other people. Speaking about imaging, the speakers reproduced phase manipulated music tracks far more accurately than anything I've heard so far. It must be the room treatments that are preserving the phase accuracy of the speakers. It was like "oh this is where it is supposed to sound!" I was also exposed to the dark secrets of the time domain in room correction. That was a revelation to me to be exposed to so much more information and tools to analyze room acoustics. Now it makes sense why and how the room is mucking up the sound. It's all in the time domain! Now I am able to correlate measurements and subjective judgment of how good (or bad) the room sounds. I have so much to dig and play around with now. Measurements really can tell you about how good something sounds if you look at the right things and how to interpret it properly. Thank you SME and his wife for being such amazingly gracious hosts. That was one hell of a weekend! Oh, and did I make it clear enough that your system sounds good?
  9. 4 points
    Gjallarhorn 2 plans. GH 2 print.pdf GH 2 print.DXF
  10. 3 points
  11. 3 points
  12. 3 points
    Looks like I've got to pick this one up if nothing else but for the fun factor. Anyone want to take bets on how many of my neighbors will complain to my HOA when I listen to this movie at a decent level? Haha.
  13. 3 points
  14. 3 points
    Crowsons and even speakers should be fine, like SME said, the LFE channel will have a lowpass that smooths out the corners. I really only found sharp corners objectionable on a few films. Tron:Legacy and Star Trek:Into Deafness were the two that are the worst standouts. But many films clip. Many times it is not objectionable. For instance, both Iron Man and Iron Man 2 clip a lot whenever the repulsors are firing, but I never found it problematic, as the closest thing to repulsors are jet engines, which clip our ears. But when you clip a violin, or something that is very familiar, it just sounds wrong. Star Trek 2009, for all its accolades, clips the warp booms (WTF are they 'supposed' to sound like?). But they still sound great. At the same time, the film clips hardly anything else. JSS
  15. 3 points
    Heheh. Yeah, I know what you mean. I believe you when you say it is better. Just poking fun a lil at your post. You're a very smart guy and knowledgeable but it almost seemed like nothing short of perfection wasn't good enough. Do don't that to yourself. You'll never be happy.... but, it sounds like you are so ignore me. Sometimes the constant "improving" can have a detrimental effect on the enjoyment of the HT room. I had to learn to love it even with the warts and all!
  16. 3 points
    Or, there may not be that much research done on this at all. If the subject has little interest outside audio/hifi - because audio research has always had a tendency to focus on technical properties that may not be very relevant, and less on hearing perception mechanisms. I did a test to find audibility limits for distortion not long ago. Look at these numbers. 440hz: 60dB 2h -34dB 2% 3h -50dB 0.32% 4h -50dB 0.32% 5h -53dB 0.22% 6h -50dB 0.32% 8h -58dB 0.13% 70dB 2h -34dB 2% 3h -50dB 0.32% 4h -54dB 0.2% 5h -65dB 0.056% 6h -64dB 0.063% 8h -72dB 0.025% 80dB 2h -34dB 2% 3h -34dB 2% 4h -43dB 0.71% 5h -65dB 0.056% 6h -72dB 0.025% 8h -76dB 0.016% This data suggests that the presence of a 80dB tone does not reduce hearing threshold when the frequency of the other low-level signal is sufficiently far away in frequency. Because you can see that detection level for higher order harmonics is lower in percentage as the volume increases, and if you plot this data into a frequency response chart, you can see that the detection level remains constant at threshold of hearing around 0dB, with a masking around the fundamental tone. The masking follows the level of the fundamental tone, but far away the detection level remains the same, regardless of fundamental tone loudness. The 80dB fundamental does not reduce hearing threshold, it only masks around the tone. Then we understand 2 things: - Dynamic range is at least 80dB for 80dB sound - Louder means more detail and more revealing to faults in the audio chain So, why did I not test for even louder fundamentals, say up to 120dB? That data could be interesting to have. When I did the test, it was for a different purpose, and 60 to 80dB was sufficient. Louder presents some challenges - more difficult to ensure that the only distortion present is what is being tested for, and listening to tones louder than 80dB up into the midrange is actually so loud it is quite unpleasant.
  17. 3 points
    That may be true, but that 140dB range does not apply for short time spans, because the ear has a built-in compressor that adjusts sensitivity according to exposed sound pressure level. If a very loud 140dB peak occurs, the sensitivity is immediately reduced, so that sound at very low spl can not be heard until the ears recalibrate, and that takes some time. Purpose of this mechanism can be to protect hearing, and also is the mechanism that actually makes it possible to have such a wide dynamic range. How large is the actual dynamic range, at a given moment, for a given spl exposure? Perhaps someone knows, I am sure there has been lots of research conducted on this. This relationship has attack time, hold delay, depends on peak vs rms level. This has consequences. We see that hearing is not a time-invariant system, because the output (what we hear) depends on what happened before in time.
  18. 3 points
    Right...That's what I mean. If you preserve incredibly high dynamic range with digital media that means your average level is going to be very low volume/signal strength, requiring much more gain to get the average sounds to a typical playback level. I wish there were more recordings like that. Just turn up the volume and the problem is solved. But the problem is, if you attempt to play a regular heavily compressed song after, it will blow your head off and make the dynamic recording sound weak in comparison. That's exactly how the loudness war started. Get the average level as high as possible. Louder=better or more noticeable. I'd like to see groups make 2 mixes. The squashed "radio" track and a much lower average volume mix with more dynamics. I see this issue as separate from your speaker system being capable of producing huge short term output. I consider that a reasonable goal that improves sound quality on a number of fronts.
  19. 3 points
    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...
  20. 2 points
    I've never been on social media. I need another time sink like a hole in the head.
  21. 2 points
    +1 This about sums up my thoughts as well. I have heard of B2 before from the car audio guys. They mention sound quality a lot on the website but I saw no technical information that explained what was done in their speakers to engineer them for better sound quality or lower distortion or whatever. They might be awesome drivers, or they might be typical cookie cutter car audio SPL comp subs. Like most of these car audio companies, they are very short on any type of engineering specs, technical data, or explanation of design goals. There is a lot of descriptive text (claims) about them but little substance. I see a number of red flags from browsing the website. A lot of the specs are different in the manual vs the website. The power handling specs have no information of how they were derived (AES, CEA, some other proprietary testing?). Same for the Xmax specs (gap geometry, what calculation, BL simulation, Klippel, pulled out of thin air?). This is typical for this market. Some of the xmax specs are peak to peak and others seem to be 1 way? Other things that would give me pause are the lack of any mention of shorting rings in the motors. 6 and 8 layer 4" diameter and larger will have huge inductance. What that means is inductive distortion will be high and your winisd sims will not even resemble the real response behavior using these drivers. Le at 1kHz isn't even listed so it is impossible to sim them in HR with the Le effects added. Also the Cms is extremely low meaning that the suspensions are rock hard. Stiffer than any other drivers I can recall. Another thing I see is that the Qts of these drivers is on the high side meaning they are very inefficient. This is despite the huge motors, massive voice coils, etc. What do I mean by a typical SPL comp car sub? Basically it comes down to this... The drivers are designed to take a beating and withstand as much abuse as possible. That is priority #1, #2 and #3. After that they may start to consider how cool the sub looks. The marketing involves having bigger everything than the competitor...Heaviest motor possible, most neodymium, biggest coil diameter, highest power handling rating, etc. Quality=Heavy & Tough in this market. None of this has anything to do with making the sub more accurate, linear, higher efficiency, or lower distortion. I'm not trying to pick on B2. It's a car audio market issue as a whole. They may have some excellent products but without sufficient information on them from the MFG it is impossible to know without trying one out.
  22. 2 points
    Those lifting straps? I've tried them, they're OK for some things like couches and beds, but not something I would use on a sub. I have a little bit of experience moving big subs. We used an appliance dolly when we had to get the pair of LilWreckers down a flight of stairs and into a basement theater. Definitely took two of us, and I'm not a small guy. LilWreckers are ~32 cubic feet and about 300 lb if I recall. Google appliance dolly images You should be able to rent or borrow an appliance dolly without too much trouble. I moved the F-20, MicroWrecker, and a number of other unnamed tapped horns with my 2-wheel dolly, but I didn't have to climb too many stairs. No matter what, using some straps to secure the sub to the dolly is a fundamental. A second person can be a huge help too. Of course, if you have another stout person handy (looking at you, @Ukko Kari) , you just pick the cabinets up and carry them, like we did with the AlpineGeists.
  23. 2 points
    I still have to do a headroom sanity check on the overall film, but I will. Only 4-5 films I have re-done have ended up with any >128dB effects when played back at 85dBRef (+7dB on the MV). rant/ Most films are VERY tolerant of BEQ, which has led me to believe that it is possible to have unclipped, dynamic, full-bandwidth presentations if someone takes the time to create a film soundtrack properly the first time. We unfortunately have few examples of this. So much of the problem is that most exhibitors will not playback films at Reference; too many complaints of "it's too loud". This sometimes forces mixers to mix films under reference, knowing their films will not be played back at Ref Level, esp for dialogue driven films. To get loudness under reference level, you have to compress/clip loud passages to keep dialogue loud and clear enough if you mix significantly under Ref. What happens if a film mixed under reference is played back AT reference level? LOUD/COMPRESSED/CLIPPED Hell. It can be even worse for HT 'home mixes' depending on the playback system and Ref Level it is mixed at. Was it optimized for soundbar, TV speaker,s, HTIB, or decent HT setup playback? And let us not forget about 'Director's Intent'. I'm talking to you, Chris Nolan, ever since 'The Dark Knight' (though I hold out hope for 'Dunkirk'), and you, Joseph Kosinski (who admitted to messing with 'Tron:Legacy's BD mix, and the clipped hell it was in every channel save for LFE). But I also have to thank Joseph Kosinski. Without Tron:Legacy's obvious clipping, I would have never tried to find out how to look for clipping in a soundtrack. I am just glad we get some decent mixes every now and then. Too many variables at play, and not many (if any) standards followed, with so many various powerful interests at play. /rant JSS
  24. 2 points
    The lowend of the Noesis 215RT was carefully designed for a flat response in room. The half space, out door response doesn't give a good indication of the in room response. The Noesis 215RT was very difficult to design because of the horn's directivity transition to the direct radiating woofers and then the spatial and room gain. The attached measurement is a Noesis 215RT, 1ft from the front wall and 3ft from the side wall, in a large, open basement, on a concrete floor.
  25. 2 points
    Ya'll crazy. This was wonderful A/V all around (saw in Dolby Cinema) and I can not wait to get it on UHD/BD to watch at home. This will probably rate well in bass too. It's time will come.
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