Originally Posted by LTD02
"No, it is making things up because you're
throwing out figures to match a result you
already know. That's rigging results."
i was just showing that under a reasonable set
of assumptions, the math works fine.
Yeah, the math can work fine, if you're just making up numbers for an answer you already know.
"If you model my enclosure and plug in all the
power numbers and all that, the result isn't
what actually happens."
then the model is incomplete. it is not accounting
for something that you are doing.
Right, its not modelling for 1 key factor, reality. The reality is you can't simulate every fine detail that would make that accurate. I'll be glad to give you exact dimensions of my car interior, give you sub parameters, and box specs, then you give me a power level and tell me exactly what number it does. Then you can explain why that number changes when I move the box to the left 4".
"Everything that you're referring to has to do
with a room, not a car. Cars act differently,
much differently, and the louder you go the
more different they act."
the physics of acoustics don't change
based on the size of the room, whether it is large,
small, car, living room, truck, stadium, or whatever.
maybe, you are trying to make a different point
that is getting lost.
I'm guessing you've never built anything for a car, ever. If it were as simple as simulation, everybody would be doing 160's with a pair of 10's and one of the loudest vehicles in the world wouldn't be struggling to get 1 more tenth for the last 4 years. FYI, hes at a 181.8.
"I couldn't have said it better myself, guess,
not data. To accomplish my goal I need data,
ok. but you came into the forum to ask for guesses
on how your horn vent would work. nobody has
the data that you need, so folks have suggested
various ways to model and various theories for
why it might or might not work.
Somebody DOES have the data I need. That data can be had in the form of "if you build a horn like this, it does this", it's not specific to how I'm using it. The general rules I was given that were said to be false I have found to be sufficient for the purpose.
"I can tell you per my testing at various power
levels (actual clamped power) I don't have 2dB
of power compression."
ok. you are aware that clamp meters don't measure
You are aware clamp meters are a required tool to measure power, right? Output current x output voltage = wattage, those of us who do that call it "clamped power" because it's not estimated power, or simulated power, or theoretical math power (using only AC voltage). 2 meters and ohms law gives actual data. I know resting DCR, I know actual playing impedance, I know impedance rise, and I know actual wattage, all because of that clamp meter that doesn't measure power.
"I told you everything that changed. 2 identical
subs, in 2 identical enclosures, with an additional
1000 watts in the same environment. The tolerance
of the equipment is 1/100th of a dB. What I was getting
at is you math doesn't work for this application, at all."
two sources is different from one source. you could
easily be getting a cancellation, or partial, based on
placement of the second sub. i won't suggest that you
had them wired out of phase by accident, but mistakes
can happen, no? could it have been erroneous data.
You're right, I could have cancellation. But that math of yours doesn't have a place for cancellation in dB's, does it? Can you simulate cancellation of having another identical enclosure directly next to the other one (like I said earlier) firing the same direction in the same manner? No. That's where DATA comes in, not simulation and math that doesn't work.