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  1. 2 points
    Last time I moved my box downstairs I rented a self climbing dolly from the rental place. It was like 40 bucks for the day and it did all the work you just balance. Ive used the same rig for moving gun safes around 1000lbs. Last safe I helped move we sat around laughing about how nobody was sore or hurt.
  2. 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.
  3. 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
  4. 1 point
    I concur that the time portion of the system response is what we must strive for correctness. Time of flight, processing delay needs to be accounted for. What I have done: in a multi-sub system, measure time of flight ( with no DSP engaged ) from each device in it's intended location to the main listening position, and compare that to the main L/C/R channels. I helped set up a system with subs that were radically different in distance, with a nearfield sub behind the MLP area. In that particular case, the closest subwoofer was set for level, and run at a bandwidth of <40 hz. Delay was set so it's time of flight was identical to the average of the main L/R speakers. The other 3 subwoofers in this large room were set so their time of flight was identical. The pair closest to the L/R were run <120hz ( main speakers were not on the level of some enthusiasts here ) The third subwoofer was run <60 hz. Subwoofers were not gain matched, the one behind the MLP was reduced considerably in level, it's 4kw amp was just idling barely with respect for the required levels. Processing added 1-1.5 msec of delay, so the main and subs required a bit of fine tuning. Once all 4 were playing 'nice' with respect to each other and the main L/R, Anthem room correction was run. Every situation is unique, and requires a customized solution. You may get better smoothing in the upper bass running all subs as full bandwidth, but may result in a softening of the attack across some of the listening positions, if there are many, due to the various complex phase relationships in different physical locations. Longer wavelengths ensure that you will have better success at integration. It's not hard to get sources within 1/4 wavelength at 20 hz, or even at 40.
  5. 1 point
    Integration basics: We start with the simple basics that everyone on this forum already knows. And then we will see that what should be quite simple and straight forward, just is not so, at least not always. Assuming the subwoofers are in place, and any eq and other settings on the bass system is completed. If it isn't perfect - well, it never is - then that's what we have. The end goal is to end up with a system with a smooth frequency response matching our chosen target and very good transient behavior. Transients means timing - we need to get the time domain right, it is not enough to just eq or whatever to get a perfect frequency response. To achieve this, we can adjust the level on the bass system to match the mains, we set delay on the mains so that the bass system and main speakers sum up correctly in the time domain, and we set a low pass filter on the bass and high pass filter on the mains - this is the crossover. The typical processor allows tuning of these parameters. Level: This is where the typical buyer fails first - level is set too high, often 20dB higher on the bass system, because the subwoofer was expensive and must be heard. The frequency response measurement effectively reveals this problem, simply adjust the level so that the frequency response matches your target as close as possible. Now if both mains and bass system are smooth/flat, this is quite easy, but can be more tricky to find the best compromise if the responses are very nonlinear. Level can usually also be adjusted on the bass system amplifier, so you don't need a typical processor for this. Delay on mains: This is the subwoofer distance setting. This should not be set to the distance to the subwoofers, it must be set to match the total delay in the bass system, which includes dsp, additional filtering, acoustic delay in subwoofers, acoustic delay due to room interaction. It will usually be a lot more than the physical distance. One method to get it right is to look at the frequency response around the crossover - the correct setting is when the bass system and mains sum up to a reasonably flat level with no dips. The problem is that there are an endless number of distances that will look right in the crossover region, because if the delay is exactly one period wrong, it will still sum up. Fortunately the frequencies involved are quite low, so the delay for one period at crossover is long, and we can see this on the time step response or in the spectrogram. Tune it approximately first, using spectrogram and time step, then fine tune using frequency response. Have an expensive audiophile preamp with no delay for mains? Well, why do you have that, sell it and get gear that is possible to set up properly to get good sound. Crossover: Choice of crossover frequency depends on main speaker response and capacity, bass system response and capabilites in the upper bass range, location of subwoofer units. Generally, a higher cf gives better results, 120hz is often a good starting point to try. If your bass system has asymmetrically located units, a lower cf is needed to avoid localization, try 80hz, in bad situations as low as 60hz can be necessary. It is also possible to run the mains with no high pass, running full range. If the main speakers have extension and capacity at low frequencies, they will now act as part of the bass system, hopefully resulting in a smoother total response. All this is quite easy to do right if the bass system and mains have flat and perfect responses. In real world scenarios, this is not the case, and decisions has to be made to choose the best compromises. It is quite clear that the set up an calibration of the bass system before integration is also a part of the integration process, and then this is no longer easy to do just by following a few rules.
  6. 1 point
    MemX - that cart is not designed for stairs and I expect would quickly break. Like LilMike mentioned, you want an appliance dolly like you’d use to move a refrigerator or washer. And then strap horizontally around the dolly just below the handles. And then strap vertically around the sub and appliance dolly support plate so the person below the dolly can help lift the sub going up and down.
  7. 1 point
    Right on! Hope it works well for you. Snakes like that are the only way to go. I'm looking at buying a long snake, then cutting it up and making custom ones for my rack, things will be so much cleaner. I am doing speaker "snakes" like that too, running L and R in a 4-wire cable from the amps to a Neutrik 4-pole in the wall. Once I used a consistent wiring pattern, that has worked well.
  8. 1 point
    Hence my post over a year ago asking for real numbers.
  9. 1 point
    Removing the drivers will help alot IME as the weight will be more evenly distributed which makes them much less of a bear to manage (and also means the driver is safe if you do have an accident with the box)
  10. 1 point
    I don't envy you. My D.O. 21" subs are about the same size and weight. Is it possible to remove the drivers? That's what I plan to do if I ever have to move mine. Then I can box and move each driver separately in their shipping boxes. I actually built the subs in the basement and then got a friend to help carry the empty cabinets (only 120-130 lbs each) upstairs. Then I loaded them in the living room, using a specialized loading platform I built with heavy duty feet in the right place to allow me to tip the cabinet on each end without squishing the surround for the driver there.
  11. 1 point
    I have some experience moving large subs unfortunately. Get yourself a decent hand truck (not the stair climbing gimmicks) and a ratchet strap (endless or continuous would be best so you don’t have to deal with the hooks). Just strap the thing down vertically and then you can pull up with the truck handles and the other person can lift the sub or the bottom of the hand truck to go upstairs. Or pay someone to move them for you, which would be my vote. Lol! EDIT: would probably recommend a second ratchet strap vertically to strap the sub to the bottom support tray, which would then allow the lower person to lift the sub more easily. And rubber coated gloves grip smooth veneered surfaces well.
  12. 1 point
    The numbers currently on the PB16's page are 95mm peak to peak Xmech and 82mm Xmax:
  13. 1 point
    Anywhere from 4-12 hours per film, with about 1/2 that time just waiting for processing to happen as I think about how to do the next trial solution. Pacific Rim took me several days. That filter was steep and hard to correct. It does get easier, though. I have done around 50 or so films and 30 or so DTS/THX/Dolby trailers. JSS
  14. 1 point
    I should amend my critique to add that keeping cost low is likely a factor that went into the optimization. We DIYers often take for granted that actual parts cost is typically a much smaller percentage of the finished product cost in a retail offering than a DIY build. I don't know a whole lot about how Klippel testing works, but the amp should be able to achieve more excursion at Fs than below because of Qtc > 0.707. This may actually suit the SVS design well if the amp is unable to achieve its "peak" power rating for any useful length of time at Fs, even despite the impedance peak. The high Qtc would provide an extra boost where the amp can't quite "get there", but the amp would be able to go full tilt into higher frequencies where the mass and inductance really hold it back. The Klippel's look real nice as far as allowing lots of excursion with low THD. It'll probably look great in a standard measurement suite including CEA. However, the inductance variance seems pretty high to me. Maybe it's fine for a budget consumer sub. Still, I'd bet that it sounds a lot better, the lower the crossover point is.
  15. 1 point
    Finally, LFE pre-post: About 7 iterations to get this one right, as headroom was at a premium. Turns out my first guess was closest to my final solution. As I expected, <10Hz is highpassed away, only able to be brought back by ever increasing negative gains before BEQ. Tentative LFE Solution: Gain -7dB Low Shelf 18Hz Q=0.707 +5.25dB Low Shelf 18Hz Q=0.707 +5.25dB Low Shelf 18Hz Q=0.707 +5.25dB SME, if you can input that into your incredible DSP, I'd be interested in what you think of the solution. JSS
  16. 1 point
    I went back and looked at the Tymphany STW-350F specs and they are totally different from the specs that ITR posted from a PB16 driver. Originally I thought that these drivers would be quite similar or were at least using a similar build platform. After looking again there is very little similar between them at all. The frames are different, the STW-350 is 15" OD but the SVS appears to be 16" OD. The STW-350 is using an overhung topology with a 7.4" diameter coil. SVS says they are using an underhung 8" nominal diameter. That being the case both the surrounds and spiders would be different. The overall motor / gap / coil geometry would be much different as well. In fact it seems like perhaps the only parts shared would maybe be the motor case and backplate. Although the motor outwardly makes the drivers seem like close brothers it appears that they are more like estranged 3rd cousins. Modeling the 2 drivers using the parameters provided shows that they behave as differently as you would expect. The SB16 driver should be a completely different 3rd driver design. I must say this has gotten me interested in testing the SVS 16's again.
  17. 1 point
    Center pre-post, looks like a decent solution: The shelves and dip cleaned up nicely. I usually shoot for a flat peak graph, I have found it sounds better than correcting for the avg graph. Others may differ. JSS
  18. 1 point
    It also says 5 kW peak amp power. You can choose to believe them or me. I will post the impedance plot for you.
  19. 1 point
    Were they attached to sharks, at least? Yes, indeed. I'm sure there is a good reason why they chose this specific driver for the task. But also... ...wasn't this an under-hung driver? IIRC, the sealed version of this system used an over-hung version of the driver. Should definitely change some paramters... ...but just doesn't seem like an optimal driver for the alignment. Welcome to DB, ITR. Good stuff.
  20. 1 point
    Sorry, I am little late to the party. Could you please point me to the newer thread, I could not find it. I did not mean that high moving mass would always be an indicative of high inductance, I was just replying to his question. T/S parameters below. Electrical Parameters Re 4.65 Ohm electrical voice coil resistance at DC Le 3.143 mH frequency independent part of voice coil inductance L2 8.938 mH para-inductance of voice coil R2 16.81 Ohm electrical resistance due to eddy current losses Cmes 898.19 µF electrical capacitance representing moving mass Lces 21.56 mH electrical inductance representing driver compliance Res 51.10 Ohm resistance due to mechanical losses fs 36.2 Hz driver resonance frequency Mechanical Parameters (using laser) Mms 491.600 g mechanical mass of driver diaphragm assembly including air load and voice coil Mmd (Sd) 464.350 g mechanical mass of voice coil and diaphragm without air load Rms 10.711 kg/s mechanical resistance of total-driver losses Cms 0.039 mm/N mechanical compliance of driver suspension Kms 25.38 N/mm mechanical stiffness of driver suspension Bl 23.395 N/A force factor (Bl product) Lambda s 0.045 suspension creep factor Loss factors Qtp 0.911 total Q-factor considering all losses Qms 10.428 mechanical Q-factor of driver in free air considering Rms only Qes 0.949 electrical Q-factor of driver in free air considering Re only Qts 0.870 total Q-factor considering Re and Rms only Other Parameters Vas 38.8458 l equivalent air volume of suspension n0 0.186 % reference efficiency (2 pi-radiation using Re) Lm 84.90 dB characteristic sound pressure level (SPL at 1m for 1W @ Re) Lnom 86.00 dB nominal sensitivity (SPL at 1m for 1W @ Zn) Series resistor 0.00 Ohm resistance of series resistor Sd 834.69 cm² diaphragm area
  21. 1 point
  22. 1 point
    Kinda off topic from the 215RT... In general if I was selling subs or speakers I'd probably aim for a flattish response to 30-35Hz and a gentle 6 to 12dB/oct roll off below there. Rooms vary a LOT but if you look at the broad trends vs individual samples most rooms seem to have some moderate boost by 20-25Hz and a large amount by 10Hz. Mine has about 3.5dB at 20Hz and about 14dB by 10Hz. There are always those examples that don't and you have your usual room issues such as the dip in the 12-17Hz range that occurs in a lot of rooms, or the peak near 40-60Hz for seating placed near the center of the room. A lot of companies go for the flat full or half space bass response. It's really a matter of preference and design choices.
  23. 1 point
  24. 1 point
    Test data and notes for the F18 18" sealed sub and its brother the FV18 vented sub are both viewable on the main site now. Please place any discussion or comments here. Thanks,
  25. 1 point
    100% of home audio speaker go into homes. Advanced room modeling software can pretty accurately predict frequency response of a speaker in room. While all rooms are different, the speaker placement is usually similar, 3-5 feet from the side walls and 1-3 feet from the front wall. Averaging the predicted in room responses in a variety `of different rooms will produce a target curve. However, this isn't as easy as is sounds because the Noesis 215RT isn't a simply subwoofer. The Noesis 215RT woofers are up in the air and receive very little boundary gain while the port is on the floor (1/2 space) and producing very large frequencies which are reinforced by the front and side walls (1/8 space). There isn't an ideal amount of boost because it is personal preference, depends on subwoofer's ability and varies with content. With movies, boosting the very bottomend is fun but then when you play music, boosting 40-120hz will give you more chest thump. Most people end up elevating from 80hz and below with the ramp starting in the 120-160hz range. Higher than that will start to hurting intelligibility.
  26. 1 point
    Those looks like bass graphs from the 'music' soundtrack, right? Typically that doesn't represent the bass levels of the movie itself. Hans Zimmer is pretty notorious for searching for the brown note on his soundtracks but a lot of the time it get's reduced or modified in the final mix once all the sound effects are competing for the same frequencies. Still, might be a nice surprise.
  27. 1 point
  28. 1 point
  29. 1 point
    After experiencing A LOT of HT systems with either: nearfield subwoofer (of various capability), Buttkickers, Crowsons... and combinations of such, they all have their pro's and con's. If you need those listed, I can do so but... I don't think you came in here looking for a run down on what is the "best tactile transducer". There really is no "this is bad, go with this instead" approach. Going from your description of your system and what you want, I'd recommend a simple sealed subwoofer-based riser. It sounds like that was your original plan. Might as well act on it. Transducers are good but different. It should be up to decide where you want to take this. But....if you want my opinion, I have not had such a revelation of tactile bass or sensation of that elusive ULF "feel" since adding this riser. After much time with it, I found that it was so powerful that I had to reign it in a bit and chose to for it to only supplement my main subwoofer system (of which the dual 18" riser would easily out-gun, sad to say) for ULF effects only. You are saying you are quite happy with the 30hz and up performance, I can't think of a better solution for you than to copy what I did. Of course there are alternatives but going off what you have posted, this would be my first recommendation. For context (important)... I chose to build a nearfield subwoofer riser for these reasons: test the waters myself of the "nearfield sub" that was heavily trending, I also had two spare 18's that I wanted to use for something, I had redesigned my HT room and had designed it around needing a riser anyway. I also had an extra amp. Just had to build a riser. Why not? Glad I did.
  30. 1 point
    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.
  31. 1 point
    Is no one going to talk about the audio in Transformers "The Last Knight" whenever Megatron is on camera? The audio has been lightly brushed on here at Data-Bass but I don't recall anyone going into detail. I SpecLab'd a few scenes last night and when Megatron lands in the salt flats the hottest spot is centered at 20 Hz. Sure it's no 7 Hz WOTW, but the sound in the movie makes it worth watching and also using for demo's. I haven't seen much talk about it so I'll go out on a limb and say that I love the proper audio in this movie.
  32. 1 point
    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.
  33. 1 point
    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.
  34. 1 point
    DONE! All links and pictures on the first page have been updated. Using IMGUR now.
  35. 1 point
    Wonder if he will "loan" me one for testing? LOL. What does he expect people to power with these? I guess it could be useful in an arena or very large concert hall. for that price I'd expect some dsp and networking options and maybe a free hat.
  36. 1 point
    Othorn files. OTHORN print AUTOCAD 2000.DXF OTHORN DXF scale print.pdf
  37. 1 point
    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.
  38. 1 point
    I have done a fair bit of design work for directional control of tweeters. I also have done horn design since 1994. So I nit pick when I hear waveguide and horn. There is so little difference that I have come up with this as a qualifying factor for one versus the other. If there is an efficiency gain in the output of the driver in the new mounting then it is a horn. If there is no gain in efficiency then it is a waveguide. The trick in that definition is that there is always some change in the efficiency of the driver when mounted in a constraining coupling area from smaller to larger. So waveguide is basically a marketing name that tried to distance the concept from terrible sounding horns. And for sure you will get me to agree that there are a lot of terrible sounding horns. There are also some really great sounding horns. If I remember correctly Genelec has one of the few smaller format monitors that claims to have a very controlled dispersion pattern. I have seen the enclosure but not worked through it's design in any detail. But it uses a combination of time delay that is naturally occurring through the cabinet design and the driver mounting coupled with some DSP correction. DSP is not magic. If your speakers sounds crappy to begin with you will only make it marginal with the most brute force correctional you can buy. That I have witnessed from one of the top DSP designers in the world. It is impressive to hear many of the warts fade. But they are still there. DSP cannot correct for poor driver design. And if there are serious resonance distortions in the drivers cone surround or spider. Those types of flawes in design will dominate the sound no matter what you do.
  39. 1 point
  40. 1 point
    Awesome! I'm glad some of these tests were useful. There's a lot of debate about how or even if these tests translate to real world use, but regardless of that one of my main goals was to test all the amps under the same conditions for comparisons sake. Before I tested the Crest CC amps I knew their 10hz and below performance was sub-par based on experience with sealed subs and real content. This amp testing confirmed my findings. There are many other examples of this but bottom line I've found how the amps perform during this testing to correlate very nicely to real world use.
  41. 1 point
    Peavey 4080 is a beast! Testing done at 20hz.
  42. 1 point
    Confucious say, "Man with two watches never know what time it is"
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