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Ricci

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Everything posted by Ricci

  1. A couple of things that I see to double check. Not sure the horn section has 133cm of length? It's a little hard to judge from the drawing scale. Could be close. Also seems like the L12 length of 37cm is possibly a little too long. SKRAM is 28cm. Is there an extra 9cm length there? Again hard to tell for sure from the drawing. I think you may need 2 or 3cm more on the overall height to get the overall volumes in the sim. Depends on bracing, etc... though. Vent doesn't look long enough to effectively be 96cm to me? Based on your dims and port area provided the panel that
  2. I use the Voxengo spectrum analyzer as an investigative tool for mixing sometimes. How is the delay plugin?
  3. Thanks for letting us know. At least you tried.
  4. Yes. It's not that the LW1400 would not work, but it would not be my first choice and I would want to be careful with the overall volume until figuring out what it could take.
  5. It's probably not a huge issue but I have seen a number of drivers with large shifts from coil center. Some were current drivers. I left a JBL 2269H sitting on it's face with 700g+ of magnets on the cone for a year to get it back to center rest position. It was probably 5 or 6mm inwardly set when I got it. It can and does happen. Back in the day it was probably a bigger issue with much shorter xmax and looser suspensions. On a modern woofer with 15mm xmax and a really tight suspension an offset of 1 or 2 mm isn't a big deal. Be more careful on drivers with a softer suspension, shorter xmax an
  6. LW1400 has a cone that is rather light and flexible for a 21". I'd be careful putting it into a cabinet which increases the pressures on the cone. S1 has a marginal impact in this type of design. Whether 300cm or 30cm. I wouldn't worry about it much. Especially at the cost of making the cab heavier or more complex.
  7. Should be fine. They are more similar than different. This one just has much less path length and gain from the front section to keep the size down.
  8. Not sure yet. Likely to be better than a direct radiator but not as good as my other designs since the driver is so close to the exits and visible from some angles.
  9. That's one of the tradeoffs of this arrangement. Could always flip them once a year.
  10. Have you considered an arrangement similar to this?
  11. Droogne, Since you have additional height you can work with, that helps immensely. 60x65x100cm should be enough for a hybrid 6th or whatever these are called lately. Keep your HR sim at about 285L and you should be in the ballpark. Keep in mind that air volume is limited and any volume taken up by the front section has to come from the back section and the ports. A bigger front section= less low bass / higher vent velocities, but can produce more upper and middle bandwidth output and lower air velocity in the front section A bigger ported chamber and ports is the exact opp
  12. Lucky dog! Quite the "toy" collection there.
  13. Since the 21DS115 is 2.2 ohm DCR I usually do consider it as 2ohm nominal. Voltage sensitivity is a tricky subject since speaker cab impedance is all over the map. Still useful but not as much as many make it out to be IMO. With that said I was trying to maintain 95ish dB at 30Hz from this cab with nominal 1W voltage. The size makes it difficult. The Edge sim was for a single cab. I threw it together quickly. A mirrored cab shows about 1dB of gain at 40Hz another 1dB over the single cab by 70Hz and an additional 1.5dB 100-200Hz.
  14. This question has a rather complicated and long answer. The simplest way I can explain it is that the S1 value is the minimum cross sectional area of the air volume in front of the driver cone at the center dust-cap. Technically there really isn't an S1 as typically defined since the driver radiation expands in 360 deg in that axis. The driver is placed in an OD rather than ND arrangement but the exit is closer to an ND arrangement. In some ways it is also similar to a traditional ported bandpass chamber. I modeled it all three ways and surprisingly there is little difference between the
  15. I wish we were closer I'd take you up on that! Especially after seeing those shop pics. Honestly I have a lot of educated guesses about the top end behavior of the front section but little in real data. It should be predictable in the bass range. Outside of that who knows...Disc diameter is 20.5" so there shouldn't be any cancellation issues until well outside of the sub range. Here's a couple of FR images. Akabak sim with the front section separated into 8 waveguides each with 12 or so segments and the 4 vents all modeled separately. The comparison FR is from HR. The two are
  16. The JBL, Martin Audio, or Harman Curve may not be a bad place to start. These are all similar in general trend to the L-Acoustics graph already posted. Some are more aggressive than others. I usually end up settling somewhere similar in shape with my systems. Gentle rise from the HF towards the midbass that continues on into the bass range.
  17. Awesome! Already ahead of the game. Is that your shop? I'm jealous of the tools and space. I have nothing like that.
  18. It may be relatively flat down to 5Hz. Can't say for sure without measurements. Curious that the spec is 30-20kHz though. If it was 20-20kHz I wouldn't question it, but 30Hz is a bit odd for an electronic component, which is why it stuck out to me. I wonder if it changes with input pad? I avoid cal files as much as possible for a measurement rig. Especially if big corrections are needed. They are a necessary evil sometimes though. Good luck. Post a frequency response if you get a chance to take one.
  19. Hmmm. Interesting. Frequency response spec looks not so great though.
  20. Correct the SP amps are already full bridge. So are Inuke6000 and NX6000 amps which is why they can't be bridged again. Most amps are half bridged. Half bridged Class D SMPS amps can get some bus pumping going on when used with HEAVY bass content. Not talking rock n roll kick drum here...Think sine wave sweeps, possibly some ULF HT type stuff. I like to use full bridged operation into subs when possible. In reality with normal content it may never be an issue. Voltage limit on the SP amps is about 126 volts (178 volts peak)
  21. I just skimmed this thread trying to catch up on everything I've missed in the last couple weeks, but I have to echo Peniku8 for the most part. I finally finished and posted my "small" 21" design earlier today. It is still significantly bigger than the dimensions you have proposed. Have a look at how the front section was done. I don't think you can shrink it any smaller than that without major performance impacts. The simple slot that was posted above by Peniku8 is the other option for keeping it as small as possible but has some limitations also. The back chamber and ports I could shrin
  22. Hey man. Nice looking build. I'm way behind and catching up around here. I like the method of shaping the ports and combating turbulence. The very first thing that I see though is wasted volume inside of the "toilet seat" (LOL...Can't unsee that now!). That volume could be used for the chamber or even the ports. You could knock a big hole or 2 through the bottom panel of the chamber into the toilet bowl area and get that volume back for the main chamber. Every little bit helps. Doesn't have to be pretty. No one will ever see that.
  23. Great work! Looks like you are putting together a quality first build. My first couple builds way back did not look this good.
  24. Hey Jay. I really think it depends on your preferences, the environment and the content. What sounds good with rock or country outdoors might not sound so great with EDM in a small venue. I'd recommend to start with something relatively flat from 30-100Hz to start and flavor it to your preference over time. If you keep track of it well you may even end up with different presets depending on the musical style or the size of the venue / outdoors.
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