AkAbak is the most flexible AFAIK. Most use HR because it's quick/easy and has most types of alignments or can be kludged for some oddballs such as the B0$3 Wave Cannon once one is familiar with its various options.
GM
GM
Well, I’ve mostly built sealed boxes up until now, so I’m on the BVR/BLH/MLTL/TQWT train now, which would you suggest from a balanced user friendly/flexibility standpoint?
Done right, sounds like what they are, truncated BLHs designed to offset baffle step diffraction [BSC]. If you haven't ever auditioned a BLH, then the closest I can come would be likened to a wide band, low tuned system loaded with large, high Vas, low Qt drivers.
GM
Hmm, guess I’ll just have to try one out. I hope at some point today to download either AkAbak or Hornresp and try to put together a sim for the BG20s and then hopefully order the drivers sometime in the next month or so.
I've had BG20 in a "K12" Karlson and in one of my fake Druid pipes (did not use the tweeter which went with Eminence's old B102) If adding a tweeter, other folks graphs show some smoothing of BG20's top by removing the whizzer. I just put a bit of bonded Dacron between the whizzer and main cone.
That’s a great looking design, Freddi. I appreciate the advice, but I’d really like to maintain the bicone/whizzer aesthetic, it’s a big draw for me. I think I mentioned it above, but several of the designs I found on the web have schematics for a notch filter that does a really good job of smoothing the top end. I’m not above using DSP, either, and I’m planning on getting one of the Dayton 4x8 units, anyway.
HR and/or Leonard Audio's TL: http://www.diyaudio.com/forums/soft...n-line-modelling-software-17.html#post5160274
Help File | Leonard Audio
If you haven't already scoped it out, MJK's site is TL/horn 'central' for your specific 'train', though requires older versions of MathCad and not quite as 'friendly', though has an active/helpful yahoo Group: Quarter Wavelength Loudspeaker Design
GM
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FWIW, historically, one of the main attractions of 'FR' drivers is severely limiting anything in the signal path and otherwise speaker design in general is using 'acoustic solutions to acoustic problems'.
GM
the tweeter was "just there" left over from its fake Druid time. I did not remove the whizzer. It sounded pretty good on Muddy Waters "Folk Singer" which has better dynamics than a lot of modern recordings.
"here's" a set of parameters perhaps resonable - this looks like the GRS BOFU
NEW 8" Extended Range Speaker.whizzer tweeter cone.8ohm.Replacement Woofer.8inch | eBay
if those specs are right then it could be used in a 3rd order sealed box to reduce box size, "boost" low end, and flatten response
here's a sim at 35 liters and ~375uF series cap. To work, it needs to be driven by a low source impedance amp (the usual solid state amp)
NEW 8" Extended Range Speaker.whizzer tweeter cone.8ohm.Replacement Woofer.8inch | eBay
if those specs are right then it could be used in a 3rd order sealed box to reduce box size, "boost" low end, and flatten response
here's a sim at 35 liters and ~375uF series cap. To work, it needs to be driven by a low source impedance amp (the usual solid state amp)
thanks for the observation - bought 1 - will see how it measures with WT3 and REW or TrueRTA
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Sorry to burst your bubble, that speaker you found on eBay is a mcm audio select, they come from newark for $10:35 http://www.newark.com/mcm-audio-sel...cfm=true&ddkey=http:en-US/Element14_US/search
I hope to hear how it sounds and see some measured parameters. I've been eying them for a bit.
I hope to hear how it sounds and see some measured parameters. I've been eying them for a bit.
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You're welcome! Looking forward to it since with GRS measured specs, very close to MCM's overall and it's relatively a lot cheaper too, so barring any serious differences would choose the cheaper MCM to tweak.
GM
my poor old (15+ yrs) pc can't even run "paint" at this point so no screen shot
- but here's what WT3 says with no break-in - I'll try running it in for a while and get a vas. I'm not sure about my WT3 calibration a few minutes ago being "on" so will re-calibrate later - assume its "ballpark"
The whizzer is glued on - or made - so tilts a few degrees from perfect. GRS's magnet backpiece is un-vented (might a dustcap vent be helpful ?) - the magnet's stray field and at the backplate has very little "pull" compared to lower q motors of the same size.
it doesn't look too terrible
Re = 8.05, fs = 58.54Hz, qts = 0.7335, qes = 0.855 (might be 0.835 ? - can't read my own writing) qms = 5.162, Le = 0.8382mH
so plausible that qts could be around 0.63 IF fs drops to 53Hz as in one Parts Express view.
if that cheap MCM meets spec them would be a good way to go. I somehow feel Newark's lower prices may mean once they're gone they're really gone (?)
- but here's what WT3 says with no break-in - I'll try running it in for a while and get a vas. I'm not sure about my WT3 calibration a few minutes ago being "on" so will re-calibrate later - assume its "ballpark"
The whizzer is glued on - or made - so tilts a few degrees from perfect. GRS's magnet backpiece is un-vented (might a dustcap vent be helpful ?) - the magnet's stray field and at the backplate has very little "pull" compared to lower q motors of the same size.
it doesn't look too terrible
Re = 8.05, fs = 58.54Hz, qts = 0.7335, qes = 0.855 (might be 0.835 ? - can't read my own writing) qms = 5.162, Le = 0.8382mH
so plausible that qts could be around 0.63 IF fs drops to 53Hz as in one Parts Express view.
if that cheap MCM meets spec them would be a good way to go. I somehow feel Newark's lower prices may mean once they're gone they're really gone (?)
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Thanks for the testing, Freddi. If memory serves, those numbers are pretty similar to the PE review numbers. With a Qts that high, seems like a MLTL might be able to reach into the mid-30s after break in.
True, but power handling drops like a stone below Fs, so either needs a BLH or plenty of room/corner gain to prop it up.
GM
GM
~10 % seems plausible without tweaking the spider, but at least it's not as high as some........
Yeah, kind of my thought too, so have been debating about just buying a bunch of these now rather than go through the hassle/cost of re-coning the B20s later.
GM
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