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  1. Today
  2. Absolutely agree here, Avengers Infinity War also seemed to be lacking about ten decibels in dynamic range, whilst also having fairly quiet dialogue and being sharply filtered. Disappointing...
  3. I found TLJ quite underwhelming even with the volume turned up and with BEQ on though perhaps my impression is coloured by my impression of the film (which I also found pretty underwhelming). FWIW I posted the per channel pva for that on avs - https://www.avsforum.com/forum/113-subwoofers-bass-transducers/2995212-bass-eq-filtered-movies.html#post57055584 - as I was curious about the relative merits of the two BEQ approaches (pre and post). It seems to be a really heavily filtered track, almost looks like they baked bass management into the track itself.
  4. Yesterday
  5. Ricci

    Ricci's Skhorn Subwoofer & Files

    Hey Paul I understand sourcing the SP amps would be expensive but more so than the IPAL mods? Those are very expensive here. More than double the price without a heatsink or the dsp interface. There is a 2 ohm 21ipal. Its not on their website. Bennett has told me they will sell it if someone asks at least here in the states. I have the pdf. I only mention it because it would be easier on the amps than the 1ohm. I don't know of an amp that will be happy with the 1ohm drivers in parallel. I don't like running half bridge amps for bass either. 2 modules per cab seems very $$$$!!!
  6. radulescu_paul_mircea

    Ricci's Skhorn Subwoofer & Files

    I wanted to post this picture from last night. They are way more powerful under 45 Hz than 6 Electrovoice Xsub. I used them all in a configuration where I had a null in the DJs spot and a good spread across the venue. With any song that had serious content under 45 Hz, if I turned mine off, the 6 dual 18 were at least 10 dB lower than the whole setup. I love their sound !
  7. SME

    Ricci's Skhorn Subwoofer & Files

    While within their limits, amps are essentially voltage control devices, so the loads in parallel won't interact via an electrical path. There may still be mechanical interactions from shared air space or external proximity/boundary/acoustic loading effects but from an electrical standpoint, the two drivers don't "see" each other. In a series configuration however, it is possible for power to be transferred between the drivers unless they're exactly the same. Any electrical or mechanical differences between the two drivers may cause energy to flow between the two, which can complicate their behavior compared to systems with all drivers in parallel. It's also possible that this interaction could couple with another interaction (say acoustic or mechanical interaction due to proximity or shared air space) in a way that leads to a feedback loop that causes unstable behavior. In reality, the differences involved are probably too small for this to be a problem most of the time. However, I believe there are always opportunities for exceptions. Some manufacturers may be more consistent than others with regard to parameters that matter. Loading drivers into a tuned enclosure (especially one with higher pressures like a horn) could amplify certain problems. Running the drivers harder where non-linearity becomes a big factor is probably likely to accentuate such problems too. But this is all really just theoretical speculation. I have no idea if any of these effects are really strong enough to cause serious problems.
  8. Other movies watched recent: "Ghost in the Shell": I liked it a lot, and it had some cool mid-bass glitch effects and a very interesting score. The bass was OK otherwise, filtered in the 20s but not too aggressively. "Jumnaji": Worst bass I've heard in a while. It had some ULF, but it had a severe 30 Hz hump and almost no mid-bass. It was loud and boomy and had absolutely no punch or clarity and almost no tactile at all. For all the attention given to ULF, I think good mid-bass is more important. Without enough mid-bass in the track, the low stuff just sounds terrible. (Edit) "Ready: Player One" with BEQ: Bass movie of the year for me. Possibly my new favorite bass movie ever. Excellent full-bandwidth sound design. Very tactile throughout. You are *there*. I kind of miss the discussion here where we gave our subjective impressions of these tracks. Maybe all of that happens at AVSForum these days?
  9. So I watched "Black Panther" finally. I played the BD 7.1 at "-1" (!), and my Denon did not indicate any dialnorm compensation was applied. I have to agree that this soundtrack has serious deficiencies caused by excessive and/or mis-configured dynamics processing. It was bad. It seemed worse than the dynamics of old analog TV. Not only were macro-dynamics largely eliminated but the compressor attack seemed to act immediately and aggressively on transiently loud sounds such as gun shots. IMO, the consequences were wide and substantially degrading to the viewing experience. The experience was passive and uninvolving. The on-screen action and actors seemed trivial and insignificant. It wasn't just special effects that were harm but also the score, dialog, ambiance, etc. The scoring involving live acoustic instruments (vs. the pop / hip-hop style music) sounded completely unnatural and irritating to listen to because of the pumping effects. In one scene, dialog alternated between a few key characters and a large crowd, both of which were rendered equally loud but of course this made the crowd sound very whimpy, and the aggressive compression really muddied their voices together. It really broke the immersion. The acting seemed quite forced throughout the movie, but I could also tell that the dialog completely lacked the dynamics which may play a big part in conveying passion and emotion. The weird thing is that even if this aggressive compression was done on purpose, perhaps to optimize for hand-held devices in high noise environments, the level of the track was extremely low. I basically had to turn things up to cinema reference level to get sound that still wasn't that loud. That's a huge amount of gain as far as hand-helds go. On most if not all such devices, this track would be difficult to hear even with the volume at max. Oddly enough though, it had some decent bass in a few places, particularly in some of the quieter scenes where there wasn't as much mid/high frequency content to compete against. The tonal balance was actually quite nice, and I experienced a surprising amount of ULF with rather strong tactile effect. A lot of ULF just makes the windows rattle and maybe shakes the floor a bit, but this was felt quite strongly in the chest area. I believe the presence of higher harmonic frequencies with good balance all the way up essential for this sensation. The ULF itself makes the least contribution to the sensation but helps fill it out and make it more real and present. It's just too bad that the good bass was totally missing from a lot of transient effects. Anyway, I have a hard time believing that the problems with this soundtrack were intentional. It's certainly possible that people misjudged the quality of the track because they were too tired or something. Or maybe people were just rushed. Maybe mistakes were made that were to difficult to correct. Still, this is bad enough that I think it'd be reasonable to ask for a correction and recall. I didn't buy this film, and have no interest in doing so after what I experienced. Still, I hope this isn't an example of Disney's future. I thought some of the Pixar films like "Coco", "Inside Out", and "Finding Dory" were fine as far as dynamics were concerned. They might have been pulled back a bit compared to typical cinema tracks, but I kind of expect that with kids movies. And anyway they still were *way more dynamic* than "Black Panther". Edit: Just to clarify with my opinions regard to discussion in some of the recent posts: I thought "Black Panther" and "The Last Jedi" were kind of at opposite ends of sound quality and performance. TLJ had very nice dynamics, it just needs high master volume to get things nice and loud. BP is about the same average loudness as TLJ was (7.1 at least) but had practically no dynamics at all, for which there's no real cure. BP really looks like a QC error as does the Thor:Ragnorok Atmos track which apparent has severe compression but only for the first half. I hope it's just these two, but I guess I'll find out how Avengers 3 is.
  10. Last week
  11. radulescu_paul_mircea

    Ricci's Skhorn Subwoofer & Files

    I don't have 2 ohms 21Ipal drivers. They do not exist for now. The power of the IPal module is exactly what a 21Ipal driver is able to handle in a well ventilated enclosure. I'm not that impressed either. But I don't have access to SpeakerPower amplifiers in Europe, especially with the taxes we have around here . It wouldn't really be a good competition for the price I can get the modules or other amps.
  12. Lucasday

    Need Advice on passive subwoofer build.

    Budget would be 500$ for subwoofer or 2. My wife’s grandpa owns a custom cabinet shop. I would like to build from solid wood if possible. I would just like a high spl subwoofer I could obtain for 500 or less that would work well with the amplifier. Size is of no issue. Just want something that would come alive on a drum solo. I apologize that I’m not well versed in this area. I greatly appreciate any input, direction, comments, feed back or the like up front. You don’t have to sugar coat advice, points of view or frustration with my mismatch collection of equipment.
  13. Ricci

    Need Advice on passive subwoofer build.

    Provide a bit more information and it will be easier to suggest something. Budget? How big can the sub be? Do you have dimensions in mind? Can you do more than one sub? Are you in the US?
  14. Ricci

    Ricci's Skhorn Subwoofer & Files

    This is why I am also skeptical that this is an issue worth worrying about. Its not like running drivers in series in a cabinet is new. This is very common practice going way back. Any drivers and cabs will exhibit differences and drivers never behave exactly the same in any scenario. That is known. What is interesting here is whether series wiring amplifies the differences vs parallel wiring. It really shouldn't. Paul B&C does have a 2ohm variant of the 21ipal. It has less motor force but would be easier to run 2 off 1 amplifier. I'm not really that impressed with the power of the Ipal module. Have you thought about the Speakerpower 6000?
  15. bear123

    HST18 D2 $399

    Have an HST-18 D2, has been driven by an inuke6k typically 10 below reference or lower, so definitely not driven hard. Price plus shipping, prefer local pickup SW PA. Will drive a reasonable distance to meet. Although most looking at this are probably familiar with this driver, it does(just) hit reference level down to 10 Hz with a compression sweep, underpowered in a 4 ft^3 sealed cab, 2500 ft^3 room. It's a beast for sure but I just don't have the budget for two or an adequate amp to drive them.
  16. Hello, this is my goal. Build passive subwoofer or woofers for a 2.1 or 2.2 system. I have a Jame loudspeaker m1000 amplifier. The amp 500 watts rms @8 ohms. 1000 @4 ohms. Receiver is a proficient m40 “ speakercraft vital 710” 80 wrms x2. Main speakers klipsch f3 . This is what I have. I mainly watch tv and movies. Music mainly rock, jazz, blues. I want a subwoofer that I can play loud and feel. This is stuff I have picked up off Craig’s list very reasonably priced. Just want an decent 2 channel experience. Thanks
  17. SME

    Ricci's Skhorn Subwoofer & Files

    Do you have any real world examples of this kind of positive feedback loop occurring, causing unexpected bottoming or failure due to uneven power dissipation? Or maybe just really bad sound? I'm skeptical, but I'm also paranoid. I'm also a bit paranoid about having multiple drivers share the same air space. I opted for a solid barrier between air spaces within my dual-opposed sealed subs. You might want to consider that too if these kinds of interactions between drivers are really a problem for you.
  18. radulescu_paul_mircea

    Ricci's Skhorn Subwoofer & Files

    No, they are single voice coil drivers. But there are 2 drivers in the same enclosure. The difference in resistance gives a small variation. That variation will change the electromagnetic parameters a bit. The variance in the magnetic field intensity adds to that. Then the mechanical parameters of the soft parts will change the general impedance curves between different drivers in identical enclosures. If this drivers are linked in series, being reactive loads, they go haywire even with small variations, because they ask for different voltages and amperages but also with different electric phase angles and this way the variance increases. Then at the onset of large nonlinearities in KMS and BL , the difference can increase quite a bit or decrease if you are lucky. But the difference in load is a difference in temperature, a positive feedback occurs in a worst case scenario. I work with my subs in a pro audio environment and they get used to the limits often. I need to get rid of this problem and the only way is by using them in parallel, with one amp per driver. This sub loaded with 2 21Pal presents a 2.25 ohms minimum load, 3.7 average in series so I would need an amp that can be stable at 1.1 ohms minimum at very low frequency and high power, meaning I'm left with 2 IPal modules per unit. From an economic point of view, it is not very good, I would be better with 2 separate single driver enclosures, where I would gain efficiency, output and portability at the same time. But a dual 21 dual IPal module ultrasubwoofer sounds very fun for fixed installations.
  19. SME

    Ricci's Skhorn Subwoofer & Files

    Are these DVC drivers? I believe manufacturing variance, possibly amplified by the loading of the cabinets, could play a role in unexpected differences in series vs. parallel performance. I don't believe such difference will only one voice coil. It is when there are multiples that you get a series connection between two VCs instead of between a VC and the amp, and that is where I can imagine some unusual electromechanical behavior to arise if manufacturing variances are significant. Just an idea.
  20. radulescu_paul_mircea

    Ricci's Skhorn Subwoofer & Files

    Off course I did flip the Voltage meters to take them out of question, I changed the polarity, I changed the frequency, I put them in parallel on the same channel or different channels. The voltage difference exhibits only when linked in series. It is way way worse when they are free air, when they are not loaded by the enclosure like under port tunnig. The excursion difference is pretty obvious when I have the hatches open. I never tested their TS parameters. 2 of the drivers are not with me for now , they went to warranty, one of the remaining will go soon. The same thing happens with the ID drivers, the voltage is extremely different when measured but in this enclosure one driver had 1 hour of break in before loading, the other didn't. After 10 hours of high level music, the difference diminished but it was present still, at about the same level as with the IPal drivers.
  21. Ricci

    Ricci's Skhorn Subwoofer & Files

    Ok. What were the driver specs used? Different for each driver I assume? That is a large difference in voltage. This would likely be caused by differences in the drivers performance rather than the wiring type unless there is a big difference in the amount or type of wire used between each driver. It makes me wonder how well matched the drivers are. If it isn't too much trouble flip the polarity or wiring on the drivers when you do this and see if it stays with a driver. Perhaps I'll investigate on mine next time I have a chance.
  22. radulescu_paul_mircea

    Ricci's Skhorn Subwoofer & Files

    I am referring to electrical series not acoustical. I confirmed my theory by Akabak first and then I measured the voltage at the drivers connectors and they differ by up to 6 V when driven with 80 V. So one driver gets 37 V and another 43 V at the same time measured at 38 Hz where driver excursion is maximum. I'm going to test them as you said Sunday. Outdoors with drivers in series and parallel impedance and magnitude.
  23. Ricci

    Ricci's Skhorn Subwoofer & Files

    Paul, I've been busy. Why do you think the series connection is causing some sort of performance impact? Is it because of the info I posted about the Skhorn/ MAUL design process and uneven driver loading and excursion profile with the MAUL? In that case the word "series" had nothing to do with electrical wiring. The word "series" is in regards to the acoustic loading of the drivers. The drivers were physically in series acoustically inside of the horn/slot. This causes uneven cone loading not the electrical wiring. The Skhorn is symmetric so this does not apply. Series connection vs parallel connection of the woofers should not amount to anything significant unless the 2 drivers are way off spec from each other, in which case you will still see this with parallel wiring. Any objective quantification of it would have to be very strictly controlled as well. Same cab, same drivers, measurement equipment, same environment, same day, etc. If you have some of this I'd like to see it. Impedance curve taken back to back with the wiring resistance compensated would be ideal.
  24. Ricci

    Equipment for sale

    I appreciate the offer but no thanks. I need to sell drivers not acquire more!
  25. bear123

    Equipment for sale

    I'd love to have these, would you consider an HST18-d2 plus some cash? I would drive to meet. I'd also trade a PA-460....would be very cool to see measurements on this popular budget driver.
  26. MemX

    New website (beta URL)

    Just having a quick look at the Systems section, I noticed that "Horn Loaded, Ported" comes under the Horn Loaded filter but not the Ported filter - should it be under both? Also, the Active and Passive filters in the Filters pop-up do work but there is not a visible column within the table that details that information - should that column be visible? Thanks for all the hard work behind this site!
  27. radulescu_paul_mircea

    Ricci's Skhorn Subwoofer & Files

    If you look at the measurement I posted since I built these 2, youll see they all are a bit different, especially between 32 and 45 hz. The first ones are with the drivers in parallel, the last ones are with drivers in series. A different Q behavior... Look also at the response of one enclosure vs 2 of them, the ports get better with 2, a higher Q and at least 1 hz lower extension. Off course some of them differ because the space where I measured them is different and no matter what post analisys I use, some reflections will get into the final impulse response, otherwhize I loose resolution and accuracy down low. these differences account for about +- 0.5 to 1 dB sometimes.
  28. radulescu_paul_mircea

    Ricci's Skhorn Subwoofer & Files

    I put my camera inside many times. it does appear to have a problem there. Also the behavior is different when drivers are in parallel, the response between 32-39 hz is 1 db higher in sensitivity, but this I still need to verify again. when the hatches are open and i pass a sine wave anywhere under 50 hz, the drivers excursion is visible and the difference can be very big, like double somewhere under Fs. I'll instal the Ipal modules on them loaded with ID and I have decided shorten the ports to go to 32 Hz instead of 28 Hz as it is now. I wanted them to be 30 hz, I thought they ended up at 29 but 28 is definitely too low, especially for the 18Sound ones. I need to cut 16 cm out of them to be able to get close to where I want them to be but I have a vertical brace in my way. from the experience with the BR with RCF and from sims, going to 32 Hz will increase the output by about 3 db under 45 hz, the output at 30 will be the same and under that it doesn't matter anymore, because the place where they will be installed doesn't need anything that low. Again, I'll have to say about the sound of it, it is absolutely fenomental. The impact that 2 of these have is awesome. I'm in the process of designing and building another set of 2 slightly modified but the same dimensions. I can't wait to hear them together. I took a measuerement between front and back. Unknown voltage, 2 subs one on top of the other, equitemporal distance, so the distance are matche in impulse delay, not in ruler. very good directivity!
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