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Everything posted by PrestonTom

  1. No, you have missed my point. Do not use carpet pad or jute (too dense). If you are having problems finding the correct material (insulation blanket), then go to home depot or lowes and buy the Rouxal "Safe n Sound". The material is too thick (3.5 inches), but you can carefully peel off the paper backing (moisture barrier) and then peel it in two again to get approximately 1-1.5 inch thick sheet. This is the simple, cheap and available. There will be enough material so that you do not need to worry about the port. In fact, keep material away from the port entrance. Is this is a new build or a retrofit? If it is retro fit, then use material similar to the existing stuff and do not try and re-design the enclosure.
  2. From the guys over on the JBL: a rule of thumb of 10% increase in apparent volume. However the details are important. 1) all sides, top and bottom (not the back of the baffle) 2) 1 to 1.5 inch thick 3) not poly fill rather something like HVAC duct liner (about 3 lb/cu ft) or sometimes pressed fiberglass or Rouxal . Of course there is the usual rambling discussion about "dust and particles".
  3. It's always fun spending someone elses money
  4. as I said .... "dependent on level" We have no idea what levels folks may choose out in the field.
  5. I seriously do not believe the KLF cabinet is undersized. I know the K31 does not have a VAS of 386 liters. I am not sure where this info is coming from. The price of the Ciare is pretty expensive BTW
  6. Not necessarily a danger, but you will pick up distortion. Of course, this will be dependent on level. I can't imagine anything will blow up unless you (or a party guest) do something insane.
  7. I am skeptical of that the simulation (or its set up is correct). The horn length and area at the mouth are usually too short & small to get true horn loading at the low frequencies (below 100-200Hz). In the jubilee (51 inches in length) there are peaks and dips at about 100, 200, 300 Hz. The differences (peak to dip) are over 6-8 dB (see the JAES paper). Now corner placement and DSP will help (yours are more likely 2 pi space however)). Your simulation shows a much smaller peak-to-dip ratio (only a few dB at most). So I would take you predictions with a grain of salt. If you are convinced, then by all means make some sawdust and find out. Perhaps a quick & dirty prototype is called for. I did not see the units - is this horn incredibly large? Good luck (and I have been wrong before), -Tom
  8. That is sad news. All my best thoughts to his friends and family.
  9. This has gotten silly. Everything we buy, consume or use has parts that the manufacturer awarded to the lowest bidder. That's right .... if they met the specs and had the lowest bid, then they got the contract. Next time you are in Walmart, Staples, Best Buy, or Target, then try and find something that was not made overseas........ good luck. Although we all deny it, price point is a determining factor. So is the labor component (for many, but not all things) cheaper overseas? ......... I hope this has not been a sudden revelation
  10. We had neighbors that spent the extra money on 9ft clearance (it was not a trivial amount). Guess what, the extra height was soon eaten up. Between various sub-contractors (plumber, HVAC, etc), the clearance disappeared. It started when the one guy ran the copper for an eventual outside faucet through the basement (perpendicular to the joists and a few inches down). The general contractor / builder apologized but said it was going to break the budget to get it redone. That was the first oops and was later followed by many more. In the end it ended up up looking like a typical basement with a low ceiling.
  11. This is on eBay right now https://www.ebay.com/itm/Yamaha-SP2060-2-In-6-Out-24-bit-96kHz-Digital-Speaker-Processor/154203111516?hash=item23e738c05c:g:kQMAAOSw3mVftrON It is ch in and 6 ch out, with the usual selections of crossovers, time delay, shelving and PEQs. Importantly it accepts digital input (both AES/EBU and S/PDIF). Some claim this has a bit of background noise, but I have not had the problem (possibly because I use digital input and attenuate after the DSP box). If purchased new they are ridiculously expensive, this is a deal. Good Luck, -Tom
  12. I hope the sale goes well. I am not sure why it is being done in this format. However, and in all seriousness, the sale would probably go better if it was done the old-fashioned way with lots of photos, clear descriptions, whether shipping or delivery is an option AND VERY IMPORTANTLY - if the price was listed. Auctions turn out to be a lousy way of doing things IMHO.
  13. There have been vigorous discussions about these over at DIYaudio
  14. The taller stands may diminish the bass output
  15. Actually I am not experienced with the Peavy design. However, I am not sure what your constraints are. I would suggest a Jubilee bass bin (my very frequent recommendation). It will sound best with the big K-402 horn, but if that violates your constraints, then the K-510 horn is surprisingly good. I would shy away from any 3rd party horns (although there may be some exceptions). The MEH recommended by Chris is also a good option. I have only seen the discussion and the measures and have not actually built one (although I have certainly toyed with the idea). My two words of advice. When it comes to the tweeter section - worry more about the horn and less about the driver (within reason). As far as the crossover and EQ - definitely go with an active DSP (even if it is an entry level model). Again, I am not sure what your constraints are. So considerations of practicality, footprint and cost have not been factored in.
  16. His advice is very suspect. When you generate the sound in a corner (or nearby) there will be the greatest number of pressure nodes being stimulated. This is good. An alternative way to conceptualize is that each boundary (floor, wall, adjacent wall) provides loading for the low frequencies. This is also good. There is a nice discussion of this (and why multiple subs make sense) in Toole's book Good luck, -Tom
  17. I guess I am old fashioned and I won't bother apologizing for that. I will say it gently: "Wandering" is not much of an excuse. Bob was a good guy.
  18. Guys, with all due respect, this thread is absolutely not the place to wander off topic about housing costs etc.
  19. If that is correct ( and I am not saying that it is) , then it is very sad news. I assume the "new" Jubilees will sound great, however their increased size and substantially increased price are going to keep a huge group of enthusiasts away. The current Jubilee is affordable and can give folks an incredible value (quality divided by price). I hope that slice of the market is not ignored.
  20. Do a search on the threads by "DJK" He has a trick for doing the steep bevel cuts on the front (divider) . It would also be a chance to do a modification to make it a ported cabinet (there are pros and cons to that that mod - so think it through). This mod was also done by DJK, but remember it requires a PEQ filter on the low end (most folks ignore this detail). Just search the threads. Good luck, -Tom
  21. I am not sure, but I think that horn is a CD (controlled dispersion). If that is the case, it will need some high end boost (it is in the physics and shared by all CD horns). This is why I get concerned about folks tossing pieces together without doing the necessary crossover / balancing chores. I hope he takes the time to do a proper job.
  22. Those number are all over the place. The Qts and VAS in particular. This makes me suspect their accuracy.
  23. The time alignment is one of the more important issues. There is no reason to guess. HolmImpulse, REW, and other packages (and these are free) will give you a reasonably precise value. Yes, you do need a microphone, but these are not expensive (and certainly worth the investment). In terms of the phase spectrum: time alignment and a driver wired out of phase are big issues and easily correctible.
  24. That is such awful news. I will always have a tremendous amount of respect for Bob. My sincerest wishes for his family and friends.
  25. I forgot. If someone is actually shopping, I think they can figure it out.
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