Helium - a true micromonitor

[kennyrayandersen]

So, I got around to doing a Hornresp model (Hornresp is more complicated to understand whether you got the inputs right IMO and not really any kind of users guide) and I got very near the original volume, and much lower than what the Winisd was coming up with.

After doing some reading, I understand that some of the equations in Winisp are a bit more simplified, but I wold have thought the box volume would be off by a factor of two. Here is the Winisd input I used:

[kennyrayandersen]

This is the input to the Hornresp that I did: The red line is a 1.4 liter box and the gray line is a 1.2 liter box. Larger box volumes actually do worse (in any case no where near the 3 liter volume that Winisd is suggesting.

[kennyrayandersen]

So, a couple guys I read liked Winisd Pro better, but I couldn't even get it to load a single driver, and when I tried to get it to auto-calculate as the help recommended, it gave me utterly nonsensical values for the other parameters. So, that was no beuno.

[kennyrayandersen]

And finally some guys were recommending Vituix. I loaded the ND19-4 into the database, and it seemed to agree well with Hornresp. Both say the driver can find joy in a 1 liter or slightly better enclosure (which seems to match Scott's original Parts Express flat-pack size). Since I'm making my own box, I just wanted to check to see whether the smaller box was optimum, or a bit squeezed. Also though you can get just a bit more bass out of it with a 1.2-1.4 liter box [it appears], the smaller box looks pretty good, if the Hornresp and Vituix sims are good. It still leaves me wondering why the Winisd is apparently off by so much?

[Chris Roemer]

To use WinISD "Pro" (I'm using 0.50a7) you don't enter all the parms you can find. with "autocalc" turned on, JUST enter:
Qes, Qms (NOT Qts - it's actually ALWAYS calc'd from Qes & Qms - but then rounded on spec sheets), Fs, Vas(watch your "units"), Re, Le, Pe, Xmax, and Sd(MOST times, when it's given, it's in cm^2, so that's what I use).

[kennyrayandersen]

To use WinISD "Pro" (I'm using 0.50a7) you don't enter all the parms you can find. with "autocalc" turned on, JUST enter:
Qes, Qms (NOT Qts - it's actually ALWAYS calc'd from Qes & Qms - but then rounded on spec sheets), Fs, Vas(watch your "units"), Re, Le, Pe, Xmax, and Sd(MOST times, when it's given, it's in cm^2, so that's what I use).

I'm probably just stupid, but when I did that, it started calculating crazy numbers. In any case, the newer beta version, you'd think, should work, it just gives me different results than Hornresp, or Vituix (which both agree pretty close. I didn't know if anyone else had seen that, like maybe it was a really small box issue or something. Right now I'm inclined to not use Winisd since it's reportedly less sophisticated and it's also the odd man out (hopefully not like the V-22 flight control computers kind of way (there were 3 on-board computers and if one went bad the other 2 were supposed to over-rule the bad one. 2 of them were installed wrong...)!

[Chris Roemer]

I know you'd THINK that a "beta" vers. was farther along than an "alpha"(test), but that's not the case here.
What was known (for quite a few yrs) as the "beta" vers. was (is) a simpler model w/quite a few "missing" graphs, compared to the newer "alpha" (a.k.a. the "Pro") vers.

I've used the Pro (alpha) vers. for many, many yrs, down to a box size of about 0.05cf (ND65s - vented) with NO issues (great results). Also model predicted (very accurately) slot ports. I've been measuring my own T/S parms for a LONG time (WT3, then DATS) AND verifying box tuning. Don't believe I've ever seen a discrepancy of more than a Hertz or 2.

[garychelette]

Is anyone still building these?
Just completed a 4ohm version for my bedroom and still have my 8ohm version for my computer. Still love these guys!

Gary