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Ricci

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Everything posted by Ricci

  1. Graph above shows THD at various voltages. Starting level = 2.83 volts Ending level = 22.5 volts
  2. I've not...I will say that the 2360A goes deeper than the K402 in practice. It legit seems to be able to provide loading / gain down to 170 or 180Hz. It needs an 8" mid shoehorned onto it really, but then the throat distortion is going to get boosted. The K-402 technically loads to a very low frequency too but it doesn't provide much useful gain at those deep freq's. The horn does play a big role. With that said. Even on the giant 2360A the Axi2050 still runs out of gas due to diaphragm displacement limitations near 300Hz. This isn't really seen until absurd output levels with more than 10 volts applied = REAL LOUD, so technically you could get away with a 300Hz Xo on that horn in most cases. Still it cleans up considerably just crossing at 400Hz on that horn and keeping the diaphragm excursion under control. Moral of the story is even after the best sims and thought put into it, test the combo and see what you've actually got. Note: The Axi2050 is quite durable. 🤪 I do wonder how good the Celestion horn for these are, but I'm not dropping that amount of money to find out. The B&C horn for the DCX462 / DCX50 also is interesting.
  3. I do like the 402 a lot. They aren't cheap if buying new. Mine were 2nd hand and have some wear and tear. Still expensive. Think it was about $1200 for the pair after shipping from Cali. Doesn't bother me because they are in an ugly warehouse room anyway. Sounds better to me than the 2360A's. The 2360A's do load the low end better / deeper.
  4. Yes I've been running these on K-402's for a couple of years. I have a ton of measurements that I planned to post but never got around to. Eventually. Long story short...None of the CD's really want to be playing down that low. They may claim 500Hz but even on a very large horn that loads decently they get nasty with any real volume. The 2050's are better than any others I'm aware of. I settled on a 370Hz Xo with mine. The distortion rises precipitously below 350Hz. They may be fine down to 300Hz in a home with 0.25 volt drive levels, but for any real use with loud playback I'd recommend no lower than 370Hz with a 3rd order filter and that's on a BIG horn like a 402 or a 2360A. For work in a pro setting in a huge venue I'd consider 500Hz the minimum with 600Hz being better/safer. None of the other CD's on the market (Except for some of the exotic dual diaphragm mid units) want anything to do with that low of a crossover in a pro use scenario, no matter what the spec sheet says. If your use is at home with flea powered amps and much more subdued playback levels you can get away with a much lower Xo. The Axi2050 provides roughly a half octave better low end extension and lower distortion when driven that low than most 4" vc 2" cd's. The top end is decent but they weren't able to totally defeat physics. Smaller, lighter diaphragm CD's will have better sensitivity, distortion and output >10kHz. The 2050 sounds fine up there but it does give up something. That's the tradeoff. I'm far more concerned with SQ in the 400-10Khz area than I am with >10kHz so it works for me. Sounds killer in the midrange. I put 22.5 volts through them during distortion testing. Wore ear plugs and shooting muffs. I am not in a hurry to do that again. It's weird when you can sense/feel the pressure from treble!
  5. Great looking build. What's the outer dimensions of the cab?
  6. Sed, Winisd isn't very accurate. It doesn't include inductance effects for subwoofers. It also doesn't include baffle and directivity effects. Sealed cabs are very easy. There really is no tuning. Put it in a 23x23x23 cube and power with a big amp. It is very hard to damage this driver. Look at the testing done here on the systems page. Note the voltage used for the maximum level output sweep. Pick an amp that can provide this voltage or under. Done.
  7. Doubtful...The only things that break in on a driver are the soft parts (suspension compliance). I'm not a big fan of DATS... Have you measured other drivers with this setup that were close to mfg spec? I know some have had good repeatable results but others have not. The more ridged and stable the driver can be made, the more accurate the results will be. You definitely want the driver in a horizontal position as well. Use a decent amount of voltage. 1 volt + is better. Driver specs are expected to vary some 30% or so by major mfg's. Double the spec is way out of whack though.
  8. Jay how many of these do you have built now? 8?
  9. Phase / time alignment is one of those things that still has a lot of voodoo surrounding it. Some would say it's overblown, others would say it's the final frontier. One thing is for sure it's a lot easier to dial it in outdoors!
  10. Live streams just aren't the same. Possible that the extra 1500 to 1800 bodies in the room soak up that much HF?
  11. Ricci

    B&C S21IB

    It's an isobaric. These are not known for huge output. The output is still limited by the excursion capability of the front firing 21. The 18's rear side of the cones are connected to the BR chamber. The front side does not radiate to the outside. The 21's rear side doesn't radiate directly into the BR chamber. It's a way that can be used to extend low end response in a smaller cab but it will not offer the output gains of using the 3 drivers conventionally. The vent size will limit the output near tuning and the 21's excursion will set the limit on the output above the tuning. Using the 2 18's and the 21 in conventional cabs (much larger of course) would greatly increase output headroom. I'm kind of surprised to see B&C use this arrangement. It's a very expensive and heavy cab due to the 3 drivers.
  12. Yeah it's heading back toward lockdown quickly here. I've already had a tour (performing not doing sound) canceled and a few spot dates with other bands that are likely to be canceled. Tour was billed right when things opened back up and reversed direction almost immediately. I've got a lot of friends who work as stage hands, or sound engineers and it's been devastating for them. It's a tough time to be a performing artist, bar or sound provider. Hell any type of person who makes a living from public gatherings.
  13. Hell yeah JM...That should make some NOISE and sound great doing it.
  14. You can use it as a vented cab without the front panel. It is designed to be used either way. If you read the initial (LONG) posts I made it goes into some detail about what the front panel "should" do. I never had a chance to fully GP test this cab design yet.
  15. Will separate...2445H CD's will ship for $200 plus shipping. Horns $500 no shipping.
  16. Hello Waipy. 8 vs 4 ohms depends on which driver. There is usually some small difference between 8ohm and 4 ohm models, but it is not enough that it would be very audible in most cases. Usually the 8ohm version will have slightly less motor force and higher Qes/Qts. I do not think you would be able to tell them apart in a blind listening test in most cases. Back panel brace T does not have an angle in the original plans. It is not divided in two. Brace Q is removed if using a plate amplifier. These may have been modified in DSL's cnc files. Neither are critical to be exactly the same as the original plans.
  17. Yep...Definitely helps get what you can from a junk AC supply
  18. 4 of these and a pair of PM90's should be quite a good sounding setup and compact for the performance available. I've not personally heard the PM90's but I've looked at the design and talked with guys who have built and heard them. The feedback and measurements are positive. Amplification will depend on budget, channel needs and available mains supply. You've got everything from Behringer at the cheap end on up through something like a PS X8. Would the PM90,s be active?
  19. Cool! Looks like a good time. Where are you located? That's a nice looking chunk of land. The Keystones are bigger than I thought. What drivers do you have in them? What drivers in the Skram's?
  20. Haha! Excellent work. I'm glad you like them. If you don't do CF/poplar/epoxy logo/acrylic front, they won't match! 😆
  21. A LOT of variation is allowed even from the best manufacturer's. SVS undoubtedly has a ton of internal documentation on the drivers. They could've sent the data to a reviewer or someone else. Word gets around. Those are the specs from the OEM?
  22. Nice link back to your website...Exactly where did these parameters for the drivers come from? Just a repost of factory SVS specs? You should be aware that the specs and Klippel results posted earlier in this thread are from a guy who knows what he is doing and has access to some of the best testing equipment available. Also driver specs that vary by up to 30% or more are considered in spec in most cases. This is very common in the industry. No two units will ever test exactly the same. The specs posted by ITR earlier are not that far off from the specs listed for the PB16U driver. Well within industry tolerance for drivers.
  23. Looks great to me. Take your time and don't worry about small details. It'll be fine. When in doubt PL premium will fill any gaps!
  24. I'm selling off the HF section of my BIG 2ch music system. 1 pair of JBL 2360A 90Hx60V horns with brackets and throats. 1 pair of JBL 2245H 8ohm compression drivers. Condition of all is used. Expect scratches, a LOT of dust, dings etc...These are old units and aren't much for looks but they perform. The 2445's have the original JBL diaphragms to my knowledge. I believe the drivers might be original to the horns FWIW. The red terminal is loose on both CD's but they've always been that way and work fine. I've been using them for a very long time and have recently bench tested both drivers to make sure that both are good to go. I'd like to keep everything together if possible. $700 takes it all... Due to the gargantuan size of the horns I am not shipping these. Local pickup in the Louisville KY area. I'm willing to drive a few hrs to meet someone halfway for an extra $50 in gas money too.
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