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Ricci

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Everything posted by Ricci

  1. All of the outdoor measurements with the Ipal's are posted on the main data bass page for the Skhorn. Have a look at the voltage sensitivity measurements. There is no processing on those and they are outdoors. Really doesn't need a lot of processing. Throw a 25Hz HPF on there and set the LPF where it matches well with the mains. They run pretty decent up till above 140Hz and the response is reasonably flat, so anything below that should be fine. The rest sorta depends on the mains, amps, environment and bass content ( limiting, etc...)
  2. Hey Chris. The Nero will make some noise but it has lower xmax, power handling and less motor force. It probably wants a bit more cabinet volume. Hard to say with out trying it though. The Mms is light too indicating a cone that may flex at war volume. CKram should be useful up to 120Hz giver or take.
  3. That's my bad PC. My inbox was full. I've cleared out some space. It should work now.
  4. I think you need a minimum of 5 posts. I haven't been on AVS in months.
  5. Yes I was factoring that in as well.
  6. In my experience the NLW9601 drivers are a little less capable than the B&C's. If you can deal with the impedance the Lavoce drivers are about the best option I know of for reasonable money.
  7. Is this an outdoor measurement? How far away is the nearest large object? Building, truck, etc? Looks like about 8db down at 30Hz compared to 100Hz. The tuning seems to be a bit under 30Hz as well. I'd expect about 4 or maybe 5dB down at tuning with those drivers. The HPF probably shaves another 1db off. Realistically this isn't too far off. Once all of the factors such as driver tolerances, construction methods, signal chain, measurement setup and atmospheric conditions are stacked up it can account for quite a bit of variation. I'd not worry about it too much if it's a little different from the model or other peoples measurements. Is the mic equidistant between the vents and the upper section or closer to one vs the other? That could account for another 1dB.
  8. I'm not aware of any. All of the neo motor woofers have gone way up in price and the availability is hit and miss. You could try a DS115 or a Lavice driver but these face the same problems. I'm not as on top of the market as I used to be so perhaps there are some newer options to look at that someone else knows of?
  9. Hello Alexlel. Thanks for the info. Interesting. A 4th order LR would be 6db down at the Xo frequency. 109Hz. The response should be slightly rising towards 120Hz with that driver without any processing at all. That's including increasing directivity/baffle step as the frequency rises. You also have a pair of cabs. I wouldn't be surprised to see the response up 4dB or so at 100Hz under these conditions. Either way that's a useful starting point with just a LPF and HPF. Lowering the LPF frequency and/or changing the slope or filter type should be able to get your XO to the mains where you want it without much extra EQ needed.
  10. Make a few posts and message me your email.
  11. I would run the Skram or Ckram sub which is smaller, instead. Splitting the Skhorn in half results in a lot of driver pressure directed into an outer panel which I'm not a fan of. It really wasn't designed to be split in half because the driver arrangement is less than ideal for that.
  12. Cone flex can be a problem but only in drivers not designed adequately for high pressure applications. It has not been a problem with any of the cab designs I've made/tested/used with 18" or larger drivers. There is a reason that modern high power sub drivers have a heavy mms and stiff suspensions. It is required for strength, control and power handling. The cone on a larger diameter driver must be stronger / thicker than a smaller diameter unit, the voice coils are massive to handle large power inputs, the suspensions are stiffer and heavier to keep things centered and prevent overshoot, fight against gravity over time, etc. Most pro audio and car audio subs are built to take a lot of abuse. This is why a pro audio 15" woofer might have a MMS of 80g but a true subwoofer might have an mms >250g. Even though the 2 might have a similar FS and Xmax rating or even power handling, they are still suited to different jobs. The 80g 15" woofer is not going to fare as well in a FLH or other high output high pressure loading.
  13. Yeah it's nice to have options and this should slot right in there with the NSW and Ipal at the top of the heap but unfortunately prices for everything have gone crazy. NSW's used to be available for $650-700.
  14. I do like 240v for running big / multiple amps. Just seems to do a better job in most cases. Speaker gasket tape FTW! I use that for the hatches, handles, drivers, etc...Always good to have on hand.
  15. Might be worthwhile if using the 21-ipals or the NSW's. Lots of $$$$ for that rig though!
  16. PM90 by Peter Morris is a well designed and well reviewed DIY top cab. If you are looking to build something. Not cheap but you know how that goes.
  17. It's not impossible but I've not run across any 8", 10" 12" or more affordable 18's that make sense for this cabinet. This sub is natively tuned much lower than most. When you tune low you lose efficiency. It also requires much more displacement to produce the same output at lower frequencies. This is basic HIL in operation. This cab requires 3 things from the driver/s to perform the way I intended when I designed it. High efficiency High power handling Large displacement (Xmax x surface area) It is very rare to find all 3 of these things in one driver. Even with unlimited budget. The smaller 8 to 12" driver sizes can meet one or maybe 2 of these but not all 3. Generally you'll get really high displacement with abysmal efficiency and bad inductance issues, or high efficiency with very little displacement potential. Especially compared to the huge cone area of a 21. The 18's give up a lot of displacement to the 21's this cab was designed for. The lowest cost driver I can recommend for this cab is the Lavoce SAN214.50. It's a shame that prices are up so much. I remember when this driver could be had for about $475. If you are really on a budget and looking to try something the Dayton Audio PSS555-8 may be worth a shot. It'll give up some output and power handling to the SAN214.50 but it's $310
  18. Seamus. Also have a look at the studies for preferred response curves. There are many. JBL, Harman, D&B and some others have published target curves... A trend emerges. Most people prefer a bit of a rise towards the bass but it doesn't start truly ramping up until below 150Hz and below 70Hz is where the true boost is. The majority of the heavy lifting is below 80Hz.
  19. The 2 way may be perceived as more powerful in the midbass region. It will not be as powerful in the low range, because system resources are being used for midbass only. If your midbass bins are crushing powerful down to say 60Hz. You would need 2 or 3x the cabinet size and power to keep up with subs at 30Hz. Take this hypothetical scenario. Assume you have 10kw of amp available and 160cu ft of cab volume. This is what'll fit in the truck space and work on the AC mains. Also assume that you have 3 different sub designs: a full bandwidth 30-120Hz sub that's 20cu ft, a 30-60Hz LF only sub that's also 20cu ft (LF extension + efficiency requires big), and midbass cabs that are 10cu ft and work 50-150Hz. System 1 is all the midbass "sub" cabs that don't get below 50Hz. You could fit 16 of these in the truck. Output would be chest caving high in the midbass, but notes below 50Hz are going to be way down in level and anything much below 40Hz is MIA. System 2 is a hybrid with 6 LF cabs covering 30-60Hz and 4 midbass bins covering 60-120Hz. Assume 1Kw per cab, so 6kW for the low octave and 4kw for the upper. This is a typical ratio and would = the same amount of truck space as system 1. You now have the bottom end that was missing from system 1 but you've reduced your midbass power greatly by moving from 16 midbass cabs down to only 4. System 3 is 8 full range subs covering the whole 30-120Hz. This much bandwidth and more is not that difficult to cover well with one design. This has the most LF performance due to all of the power and all of the cabinet volume is available for the LF <60Hz. 8 cabs vs 6 and 10kW vs 6kw or some lesser amount. It still wouldn't touch the midbass output of system 1 because the system is now optimized to extend much lower. However it may equal or better the midbass output from system 2. 4 midbass cabs equaling a much smaller total volume and on less power vs 8 subs with all of the cab volume and power available. Also there is no crossover in the bass region. Output can be adjusted to taste with EQ. This is over simplified but you get the gist. Again not saying this is correct or the only way to do things. Lot's of people love their 2 and 3 way bass systems. I think it's partly due to the flexibility to turn up one section or another as an easy way to EQ the sound to taste. The takeaway is that going for lower frequencies has tradeoffs.
  20. Also does anyone around here have a Skram or 2 they would be willing to sell me, or build me?
  21. As far as damping factor goes...This really only becomes an issue under extreme circumstances with low impedances and long cable runs. Use heavy gauge wire and avoid long runs from the amp when possible. This also avoids voltage losses as much as possible. Bridging amps for subs is also good advice. Typically in a sub system there will be multiple drivers in multiple cabs. This opens up many wiring possibilities and different impedances. In some cases the 8 ohm driver might be a better fit than the 4ohm or vice versa. The 4 ohm 21SW152 is a bit more efficient than the 8 ohm, but otherwise they perform similarly. Which makes more sense depends on how many drivers you plan to use and your amplification.
  22. Hello Seamus... Personally I'm not a fan of subdividing the bass region into a 2-way for only covering roughly 30-120Hz, but a lot of people prefer this. The reason that I do not is because 50-150Hz bass/midbass is easy. Has been for decades. 25-50Hz octave is much harder and requires more cab size, driver displacement and power. Every octave lower in frequency requires 4X the air displacement to maintain the same SPL. Most people have some type of limit on the amount of gear they can haul, both size and weight, the amplifier power available, cost, etc...A good sub design can run up to 100-120Hz and good mains can get down to meet them with power. The resources used for the midbass/kick bins could be used in the bottom of the sub range and the mains. It's also slightly more complicated to setup a 3 or 4 way system. Opinions differ on this. A lot of it is personal preference and the way people like to EQ or flavor their sound.
  23. Santo, Please read through my forum threads on the RF 19 and the testing notes and data. Much of this is already covered. You may not get a response as extended as mine without EQ. The room is a huge factor. Without the room the response would be almost exactly what is seen in the outdoor GP tests. I knew exactly what my room acoustics were doing in the bass region before I moved to the 19's. I was not guessing what the resulting response shape would be. I have no idea what it would be for your room / placements. Not recommended for sealed cabs is based on antiquated thinking from the old days before there was modern DSP. Efficient drivers with low Qts weren't recommended for sealed because the raw voltage response isn't flat and the F3 or F10 occurs at higher bass frequencies. This is almost entirely irrelevant in the modern era. Any competent pro, home, HT, cinema, DIY, system will be making use of DSP. Bass performance in sealed cabs comes down to a few relatively simple factors: Power handling, high linear displacement potential (SD x Xmax), efficiency and mechanical durability. Raw FR is far less important than it used to be. RF is a car audio brand targeting SPL competition type applications. A completely different environment than any other real world use. EQ is not usually used for SPL comps and loud daily car systems. DSP is used for SQ based car audio but this woofer is not marketed as that. However when looking at the engineering in the driver if one were to make a laundry list of design attributes that result in a "SQ" based driver on steroids it ticks all the boxes. That's why I decided to test one originally. Most of the above applies to any bass driver not just the 19. Anyway...I would start planning things by looking at your room, budget, listening habits, WAF, etc...And work a solution with a "system" approach. There are a number of viable approaches and drivers to use. IB, Sealed, vented, SBA, DBA, horns, nearfield, tactile transducers...For example a properly executed DBA is objectively one of the least compromised approaches, but not everyone can execute one in their space and you would not want or need to use SI24's, 6021's, or RF19 type beasts for that.
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