Jump to content

Leaderboard


Popular Content

Showing content with the highest reputation since 01/17/2018 in all areas

  1. 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?
  2. 5 points
    I vote that we let users add graphs, content, build plans, etc. 1 guy can only produce so much content. As far as social media I'll let you guys in on a secret. I've never been active on any form of social media. I don't plan to be either. From what I recall Kyle isn't either. That's why we don't have any of that for DB! Neither one of us wants to deal with it!
  3. 4 points
    Here is a RTA of thunder I took with my calibrated-to-4hz Dayton EMM-6 and a TASCAM US-1641 which starts dropping off at 20hz. The mic was inside a window behind the curtain with its windscreen on and SPL is uncalibrated but it clipped my mic just when it hit that peak at 4hz, and I had my mic at 3/4 of gain, so it was a pretty loud peak. The second image is with no smoothing was taken during the RTA. The first has 1/48th octave smoothing and is the total peak. I live far out in the country so there are no sources of infrasound from vehicles or factories except for a very low level 14hz tone from a glass plant about three miles away.
  4. 4 points
    Make sure you put a finish on the cab before you install the driver. I have had cabs that went without finish for 3 years, b/c after the driver goes in, it is so easy to just listen to it. JSS
  5. 4 points
    The Incredible Hulk is still the track I compare all others to. A close second is the Star Trek reboot, War of the Worlds, and all of the 5-Star films on the first page of the thread. For lots of 20Hz and below energy, Battle:LA is hard to beat as well. JSS
  6. 3 points
    the site is fine, the SSL cert expired for some reason, I'm really putting all energy into new site and getting off old one, sorry for down time. Should be fixed now, let me know
  7. 3 points
    I think what db does better than many other sites / forums is that discussion here can be backed by real numbers. Subjectivity, while is fun to discuss and does have value, can't really run unchecked to the existing data. Now, data does not capture everything, and I will admit that there is a certain adoration I hold for some subwoofers that don't even hold a candle to most things in our list and I'm not shy about it. Its fun to discuss everything, big, small, expensive and cheap, don't worry about getting ridiculed.
  8. 3 points
    The lower peak substantially depends on the suspension compliance, which is probably the least accurate T/S parameter given and the most likely to change with break-in as well as temperature and humidity.
  9. 3 points
    Three years.... Weak.... I am still rocking the OG MicroWrecker (since 2013)... No finish, not even sanded, still has big PL boogers on it.
  10. 3 points
    Hi max, long time no see. Hope you're doing well as well as the rest of you guys here on DB. I found something that I think is pretty cool that might interest you. It's a VST plugin (typically used in DAW's for recording) by iZotope that takes a clipped signal and "de-clips" it: For example I put down a bass part and intentionally clipped it: Close up of the clipped signal: After applying the de-clipper: After de-clipping zoomed in: Anybody who was bothered by a clipped soundtrack could put the separated channels into a DAW like Audacity, apply this, export it to disc and then apply max's BEQ to it to bring out the best of the low stuff. Just an idea... I know that it's a lot of work and that the production houses should just give us a proper product but it is what it is. Anyway, keep cool fellas... let the bass be with you and whatnot.
  11. 3 points
    This doesn't solve the phase match problem. If one uses a textbook electrical LR4, then the phase shift of the high pass and low pass filter will be identical vs. frequency. However, unless the speaker and sub(s) are ruler flat throughout the crossover region and co-located, they likely won't be phase-matched to begin with. The THX crossover was developed assuming the mains were sealed and had a natural Qtc=0.707 (Butterworth) 2nd roll-off. Two cascaded 2nd-order Butterworths makes an LR4, so the THX crossover applied a single 2nd order Butterworth to the mains and a full LR4 LPF to the subs. Provided that the subs didn't roll-off anywhere within the crossover region, that the mains behaved precisely as specified, and that they were co-located such that room effects applied to each equally, the result was ideal. In reality of course, "bass management" is a stinking mess. The whole point of it was that one could put the subs somewhere better for sub bass, but often the "better" locations are not so good for integrating with mains, especially where multi-listener is a priority. And of course, very few mains are sealed with perfect Qtc 0.707 and Fb 80 Hz. Any significant deviations from there substantially influence the phase response in the critical crossover region. Most mains these days are ported and tuned well below 80 Hz, so they have only slight phase shift at that point. They would do better with a full LR4 HPF, but few AVRs / processors seem to offer more than one XO type. My Denon AVR has the THX 2nd order 0.707 HPF baked in, which totally destroys the bass-managed mid-bass response with any speakers I've owned. The LFE response may measure picture perfect, but the mid-bass response of the other channels looks like trash. Also, how many subs are actually flat through the XO? Most of the beefier drivers are already dropping off from inductance effects. Sad to say, home theater "technology" is still stuck in the 90s in many respects. Great sound pretty much requires extensive customization, as I've learned over the years, and the affordable options for doing so leave a lot to be desired.
  12. 3 points
    Commercial cinemas, when designed, implemented, and maintained properly provide a great low frequency experience, similar to a well done live concert. The caveat is that the experience does not extend much lower than 25-30Hz. Most impact/slam is between 40-100Hz and even higher in frequency. We are freaks here that can monitor and playback the lowest frequencies, that are often taken out of a mix that is CREATED and is meant to be played on a cinema system (25-30Hz vented, high sensitivity subwoofers). While mixing stages have existed in the past that could monitor into the low teens Hz-wise, most cannot monitor below the high-20s. We sometimes are surprised by mixes that do not exclude the content below 30Hz, as those mixes are a significantly different experience in a properly equipped home theatre. Your friends may simply be used to a certain frequency and level of low frequency experience, and call that 'good'. The EQ mixing described is in the Bass EQ for movies thread on this forum. JSS
  13. 3 points
    Valerian and the City of 1000 Planets: Good improvement on this one, esp the Intruder scenes. Tough correction, lots more infra in C than in LRS. LFE Gain -7dB Low Shelf 17Hz, S=2.5, +3dB Low Shelf 18Hz, S=2.5, +3dB Low Shelf 19Hz, S=2.5, +3dB Low Shelf 20Hz, S=2.5, +3dB Low Shelf 34Hz, S=0.5, +0.75dB Low Shelf 36Hz, S=0.5, +0.75dB Low Shelf 38Hz, S=0.5, +0.75dB Low Shelf 40Hz, S=0.5, +0.75dB Center Gain -7dB Low Shelf 30Hz, S=2.5, +3.75dB (4 filters for total of 15dB) Low Shelf 60Hz, S=0.5, +3dB LRS Gain -7dB Low Shelf 25Hz, S= 2.5, +6dB Low Shelf 26Hz, S=2.5, +6dB Low Shelf 27Hz, S=2.5, +6dB Low Shelf 28Hz, S=2.5, +6dB Low Shelf 50Hz, S=0.5, +1dB Low Shelf 52Hz, S=0.5, +1dB Low Shelf 54Hz, S=0.5, +1dB Low Shelf 56Hz, S=0.5, +1dB Low Shelf 70Hz, S=0.5, +1dB JSS
  14. 3 points
    Thanks Kyle! Actually, he jumped the gun a bit here and declared victory while the update was still running. NOW it's all done. Edit: Total count of posts updated: 169!
  15. 3 points
    Very Interesting. While nothing here constitutes definite proof, it does seem reasonable to me that the streaming version is a cinema track mix-down; whereas, the BD version is a re-EQed dedicated home mix. As I've argued before, cinema tracks need quite a bit more low frequency oomph for good impact in an X-curve calibrated cinema. That's because X-curve calibration undoes the natural in-room bass rise exhibited by an anechoic flat speaker due to boundary gain and reverb build-up. Of course a lot of people at home also have systems with less bass output, either because they calibrate to a flat curve (e.g. Audyssey) or because their speakers lack BSC or because they have boundary interference problems. Nevertheless, it appears that recent BD releases with home mixes done at Skywalker Sound Studios have re-EQ to better match systems that perform optimally for music playback. In terms of the graphs, the streaming version looks 5-7 dB hotter through much of the sub region. However, the gap may be much smaller after compensating for loudness differences in the mids and highs. In that case, it may be more accurate to say that the BD version is hotter than the streaming version in the 15-35 Hz region. Certainly the shift of balance toward deep bass could reduce the apparent level of mid-bass, even if the SPL is similar after compensating for loudness difference in the mids and highs. There's a good chance I'll buy the BD version of this film. I may be tempted to try out the streaming version to satisfy my curiosity. I could give my opinion as to whether the streaming version sounds like it is influenced by cinema EQ, for what that's worth. That UHD Atmos tracks often sound louder than BD DTS-MA is a curiosity. Almost all DTS-MA tracks have "0" dialnorm offset, and I don't believe any format supports positive offsets. It's possible that a lot of Atmos "home" tracks are just mixed hotter than the cinema versions, from which the DTS-MA may be derived from. Unfortunately, there are still no formal standards for home mixing and apparently no consistency between studios. For example, I believe (based purely on my subjective evaluation) that Skywalker Sound Studios applies re-EQ to home mixes, whereas most other studios don't. Skywalker Sound also appears to have a dedicated mix room and to use a calibration/mix level that's comparable (in terms of room size differences) to cinemas, i.e. 80-82 dBC @ 500-2kHz. Such mixes are likely to sound quieter, in addition to benefiting from more headroom and cleaner micro-dynamics than cinema mixes. OTOH, it appears that some studios monitor home mixes with calibration as low as (or maybe even lower than) 75 dBC and may still be monitoring near-field in a large room. Such tracks are likely to sound even hotter than cinema tracks and have more potential for clipping and other problems. Also under those conditions, the need for re-EQ is likely to be much less obvious for a number of reasons: (1) tonal imbalances are much less obvious and offensive at lower levels especially excess brightness; (2) lack of boundaries reduces low frequency boundary gain that boosts the bass of flat speakers / mid-field monitors in "small" rooms; and (3) per Floyd Toole, rooms with early reflections are more revealing of tonal balance flaws in a speaker, and I'd argue that this extends to soundtracks as well. From my knowledge, near-field monitoring in a large room is probably the worst environment to monitor a home mix in. Simply monitoring the mix on the dub-stage system, albeit with a Harman-like curve instead of the stupid X-curve, is likely to offer better translation than "near-field". Somehow I need to get the industry people over to my house to listen to and compare mixes.
  16. 3 points
  17. 2 points
    FWIW I ended up ordering 3 TD12X on the 9th May and they were shipped on the 25th, they landed in the UK just now apparently so should be with me in the next day or two. I also have a faitalpro 12rs1066 to go in the initial (smaller) woofer, seems like a fairly beefy little thing https://imgur.com/a/lMGuhqm surround seems rather enormous I chose this on the grounds it is comfortable in a pretty tiny box and aimed for a tune that in the high 30s, result was a 37Hz tune https://imgur.com/a/4bmN268 https://imgur.com/a/xrXFi0Q it's going in this box (NB: the pole was just to check the fit, not actually going to deploy like this) https://imgur.com/a/5FpHtdy powered by a hypex fusion plate amp crossing to the small syns at ~150Hz
  18. 2 points
    Cheers Mike for helping Samps out.
  19. 2 points
    Let me see if I got it right: You found a suitable horn (lilmike's F20?), a suitable driver for this horn (pro driver), the size is not an issue, you have cabinet builder ready to make them for you, and you have a friend willing to assist in calibration & setup. Build it. If you go for anything else, you will regret because you will always wonder how those horn would sound. Integration of these horns will be no more problematic than the sub you already have, the worst case scenario is that you achieve a similar result. It can be solved. But first - build the horns. No need to go deep into all potential problems up front. Now I am looking forward to read about how this turned out, how it sounds.
  20. 2 points
    I think "How to Train Your Dragon" should be near the top of the list for ULF as well, and it's also a pretty good movie if you like family / animation. Some would argue it's tilted toward the bottom a bit too much. The movie is full of ULF, but one noteworthy scene is maybe 1/3 of the way through in a large hall with a lot of thunder and a big door slam. That door really gets the air moving and is very noticeable because it is an isolated effect. Another animated movie with great overall bass and plenty of ULF is "9". It has many good effects. Among my favorites are the scene about 1/4 of the way through which bombs being dropped and huge mecha stomping around. A good one-off effect is the firing of the artillery near the end. The Dolby Atmos trailers I'm familiar with don't have a lot of ULF, but there are a few minor moments. In "Amaze", the "thundering bass" scene has some 14 Hz. I think it also has some 16 Hz at the very end. IIRC the leaf demo also has some 16 Hz at the end but nothing else. The "Horizon" demo has a few moments with moderate ULF, but it's completely inconsistent. The "Unfold" demo actually has good extension but isn't especially loud. Unfortunately, the trend with newer movies seems to be more filtering. A handful of us are able to work around this issue by re-EQing the soundtrack before bass management. Other than "Hacksaw Ridge", another recent Atmos mix that has ULF is "Wonder Woman". Even though most of the content is above 20 Hz, there's enough below 20 Hz to matter and the bass overall is top notch IMO.
  21. 2 points
    Star Wars: The Last Jedi Pre/Post: Significant improvement, all the effects that should have more infrasonics gain some, especially effects that are close to the viewer/camera. Lots of infrasonic noise in the track, so the highpasses are necessary to avoid a DC offset to the track, since we boost those infrasonics so much. The track with the below changes played back at +4dBRef (equivalent reference level) has a Dynamics score of 31.26dB, and no effect is greater than 121dB, no extended effect greater than 114dB. Capable systems will like this correction. Do not apply this correction on top of a 'house curve'. At most, a smooth 10dB rise from 20kHz to 20Hz is all that is needed. Correction was applied to the 7.1 channel bed of the ATMOS track, the DTS track is similar, but I did not test this correction on it. LFE: Gain -4dB Low Shelf 14Hz, Slope 1, +5dB Low Shelf 15Hz, Slope 1, +5dB Low Shelf 16Hz, Slope 1, +5dB Low Shelf 17Hz, Slope 1, +5dB PEQ 20Hz BW 1 octave, +3dB PEQ 65Hz BW 0.75 octave, +1.25dB Highpass 6dB/octave 3Hz LCR: Gain -4dB Low Shelf 20Hz Slope 1, +6dB (3 filters for 18dB total) Highpass 6dB/octave 3Hz Surrounds: Gain -4dB Low Shelf 40Hz Slope 1, +6dB (6 filters for 36dB total) Low Shelf 45Hz Slope 0.5, +6dB (2 filters for 12dB total) Highpass 6dB/octave 10Hz JSS
  22. 2 points
    v1 is 7 years running! v2: Just fixing some bugs and coming up with a migration plan. The migration is still pretty massive but I'm happy that we have got this far! The new site is going to be a huge upgrade and I'm excited to get this launched for the community Overall, not a lot of "new" features but mostly just making everything a whole lot better and easier to go forward/change improve. This gives us a platform for another 6 or 7 years. Old site SQL / PHP / JS Custom CMS build from ground up, limited features, small images, poor scalability. Shared server, not on cloud New site Tech Non-relational database Reactjs front end w/ custom CMS build in react/redux Most UI components are built from scratch with an updated look/feel Single page web app design provides a much richer user experience Template driven graphs for better control / flexibility and standardization of data Custom services (nodejs) for document storage with reliable payload validation for easier error handling and service construction Much better UI for image management Far improved CND store for images (using Amazon S3 and Lambda for on-the-fly image scaling/caching) Server is custom Heroku Dyno (Cloud based) with a .git repo UI Far improved readability and image UI Compare feature is more full featured and you can compare up to 4 systems at once. Added max output content section (similar to CEA2010, but no THD limits) Drivers now get their own graphs too. We'll port the impedance curves over.
  23. 2 points
    Ok...Finally got time to write up a post. Went back and updated the HR sim data for the Skhorn. The original sims prior to measuring the final speaker were not such a good match. Turns out my choice of placement of S3, S4 and S5 with the limited amount of sections in HR were not all they could've been. Incorporating the air volume in the driver cones rather into S2, instead of using Vtc and Atc, was a much closer match for this design. The other big improvement was moving S3 to the smallest section, directly after the drivers and incorporating the large air volume in the final corners of the horn section into S4. Sim is much closer now. Still not perfect, but probably about as good as it will get using HR. I believe I have learned another couple of tricks to make HR sims for horns more accurate by revisiting this but I'll need to verify in a couple more cases to be sure it applies to more than just this cab. Took some more time and looked at the Edge program vs measurements and sims and it lines up very well. Looky there the math works! Here is the new HR input for the Skhorn. This is the GP measurement of the Skhorn cab at 14.1 volts (normalized back to 1.41v) compared with the same measurement with the baffle effects as calculated by Edge removed from the measurement. Here is the measured response, once again using the Edge program cal file from the above graph, compared with the improved HR sim. This is a good match. This is the same graph as above but with the original HR sim from back before the cab was measured added in as the blue line. It was not a very good match.
  24. 2 points
    Othorn files. OTHORN print AUTOCAD 2000.DXF OTHORN DXF scale print.pdf OTHORN print.pdf
  25. 2 points
    Thanks Mike. I must've gave everyone reading information overload. The sims with some of those drivers listed above look quite good to my eye. Vent compression at war volume is my main concern with it. Now I just need to get one built. I'm working on that 8hz horn Scott wants but for some reason I just can't get it to work while still fitting through a doorway. I don't understand what's going on. Might have to try my new, experimental, patent pending, rotary, quadratic, bi-phase, 10th order, sub-harmonic re-accumulator cabinet to get it to work right.
×