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lilmike

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Everything posted by lilmike

  1. Try em in Hornresp. Nothing special, just a simple floor-to-ceiling single fold. Tune comes in about 22 Hz. Epically good. Big coil means it soaks up the power and has a nice low inductance too. The temptation is strong with these... Honestly, If I did not have 4 of the 18" 9601s, these would already be in my theater.
  2. I know, right?? Please, someone buy the 9601s so I don't.
  3. Man, that turned out nice and clean! Doesn't look anything like ice cream though...
  4. Wait - what? Did I just see WiSounds post? How the hell are you man?
  5. Why use an amp? Why not use a welder? A sine-wave is a sine wave. My TIG welder can handle short circuits and since it is a TIG, I have a foot pedal for controlling current. Just a thought.
  6. Just an ugly, empty MicroWrecker cabinet. Free to a good home, but you gotta come and fetch it. I'm south of Seattle, Washington.
  7. Man - you're killing me... I want those 9601s, but I sure as hell don't need them. I still have a pair of their 18" little brothers waiting for me to get off my ass and do something with them. Somebody buy these so I don't.
  8. I'll be following along. I really, really want some Synergy horns, I was experimenting with some a while back, but lots of other things got in the way of ever finishing them. I was fortunate enough to be able to check out Bill Waslo's current setups recently,. that definitely rekindled the desire to have my own. As usual, I have plenty of ideas, lots of parts, and nowhere near enough time to turn any of it into reality.
  9. That's a full day... Looking forward to the results.
  10. Gonna be tight fitting a driver of ANY capability sideways in a 14.5" space. I've got a pair of single-folds in my theater, those cabinets are only 16.5" deep externally, and the drivers (18Sound 18NLW9601s) are a snug fit. I couldn't make these much narrower, maybe a half inch. That's still a couple inches too big for this application. My main issue with 12-inch drivers has been finding a good one. I have basically quit looking, all the cool kids are running 21s these days anyhow. Alpine's old Type R 12 was a decent tapped horn driver, one of the better 12s I worked with. No idea about their current drivers, and the engineer I know that used to work there has long since moved on. They'd handle 25 Hz without trouble, possibly lower. You'll probably need multiples though. I have an old thread at AVS that goes through basic tapped horn simulation, design and folding. It covers how to do a single fold pretty well. Another option would be to make a mouth extension through the joist bays and run the horns perpendicular to the joists. My 18s have a mouth that is 13" high. B&C's 15TBX100 and 15SW115 are both good performers in tapped horns and 25 Hz is within their reach, though highpassing is mandatory. A single fold with those might fit into 14.5", but you should draw it up with the actual driver dimensions to be sure.
  11. How much width between the joists? How much clear length? What sort of SPL and extension are you after? A single-fold tapped horn might work.
  12. As Ricci mentioned - no need for the MinDSP when there is DSP built into the amp. The Behringer DSP is plenty good, and won't result in ground loops or signal level issues, just plug it in, configure things, and it works. I fan-modded my iNuke 3000D about 3 days after I bought it. I've run it plenty hard, it is still going strong. I don't recall the process as being all that complicated (at least for someone that's used to taking things apart), really, you just need to make sure you point the new fan in the right direction and put the shroud (if there is one) onto the new fan positioned the same way as it was on the old one. Pretty sure I used a Noctua fan I bought on Amazon, it wasn't anything all that special. I seem to recall that I chose to cut the factory fan wire to connect the new fan, red to red, black to black, the RPM wire isn't used. So long as you're not pushing the amp to extreme limits with high output into a low impedance load, the fan mod should not result in anything but a quieter amp.
  13. We're not all "landed gentry" here in the states, but I completely understand your situation. Still - the set of measurements above? We did those out in the middle of the street in front of my friend's house. Those are actual, calibrated SPLs measured at a meter groundplane. We did get to meet a few of the neighbors during this process. I've also considered using a DC source (or even a really slow sine wave) to measure excursion from rest. Step up the voltage applied and check the one-way displacement from rest at each level. For measuring displacement, I've seen people use a pencil or dowel on a measuring tape. When you get to a point where more volts means no more displacement, you found a practical displacement limit. I have no idea if this will even work, and no idea if a typical voice coil motor will put up with this sort of abuse. Seems to me that if the signal is brief enough, heating should be minimal until drive levels get extreme, so it might work for a smaller woofer. One of these days when I have some free time I will give something like this a shot with a driver that I can afford to let the magic smoke out of.
  14. Fundamentally, SPL is directly proportional to excursion, and running out of xmax means running into distortion. This is something that can be measured with DIY-grade gear Still gonna take a series of outdoor groundplane measurements, and you won't have a number in millimeters to brag online about, but one can pretty easily determine the practical limits of their gear with a series of stepped-power groundplane sweeps. Start at a watt, with the mic at a meter, and make a sweep, noting your drive level. Add 3 dB by increasing the drive in REW and make another sweep. Compare the results and look at distortion levels. When you get to a point where your distortion increases dramatically or you're putting 3 dB of additional power into the driver that's not coming out as more SPL (power compression), you found the limit. Make a note of that drive level in REW, then do a little math to figure out the amount of power you can apply and stay within the reasonable operating limits for your gear. Wattage limit = 10^(difference in drive levels)/10). Say you were at -35 dB for the REW attenuator at the 1-watt sweep, and you saw 3 dB of power compression with the attenuator set at -10 dB. This is a difference of 25 dB, so the formula will be 10^(25/10) so 10^2.5, or 316 watts. For higher-SPL systems, you may need to attenuate the mic or position it at 4 meters rather than 1 meter. In the case of the sweep set I attached, I don't have distortion data (predates that feature in REW), but you can clearly see the onset of compression in the highest-SPL sweep. We either ran out of driver, amplifier, or both at that point.
  15. Definitely following along.
  16. Not too many closets in my house, unfortunately. Poor planning on my part. I have a bunch of random O-rings out in the shop, I just need to see if I have any that fit the knobs. Clearly, this mod is high on my list of priorities.
  17. At least they aren't blue. I read somewhere that I can shove an o-ring behind the knobs and significantly reduce the glow. I might have to try that.
  18. Man - I'd buy one just to get rid of the orange halos on the iNuke knobs. They do look much nicer. The only gripe I have with the iNuke's DSP implementation is the 20 Hz limit.
  19. Excellent writeup and cool project. I've thought using them a couple times, but never actually worked with passives. Sounds like you're happy with the SLAPS? It is sad that Alpine pulled the plug on the Type R 15s (all 15s, as far as I can tell).
  20. You'll most likely get this built and fully tested before I get anything done with my projects. Thanks for sharing the renderings and concept.
  21. I know. I've waited like two whole days already...
  22. I'll add a second to Ricci's post. I typically measure big drivers at about a watt applied, so 2V for a 4R driver, 2.83V for an 8R driver. My DATS and WT2 aren't quite enough for the big drivers, the Clio Pocket does OK though. The Clio manual recommends the lowest drive level that yields a clean signal. The headphone out on the UCA202 is almost enough power, but the crosstalk killed it as a contender, Pity, it was widely available and only $30. I haven't tried the headphone outs on the other Behringer USB interfaces I have. Maybe one of these days... When I need an amp, I use an old single-channel amp I got from a buddy now, it is an old TOA. Overkill for the low level stuff and it weighs WAY too much to move around, but it was free and does the job. Be sure to use a good meter and watch voltages when using an amp, it's way too easy to send more signal than the sound card can handle. Back to back Zener diodes and/or voltage dividers are a good idea. Yeah - my last post was ambitious... It has been damn near 6 months and I still haven't had the time to pull final specs and design final boxes. Worse yet, I am rapidly working my way through my stash of plywood building other projects.
  23. Without accurate driver specs and Thiele-Small parameters there is no way anyone can design or predict anything.
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