Winisd Graph interpretation ... Expert box builders.

[rickymac21 10+ year member]

So the quest continues on designing the perfect box...

This graph shows 2 15" sdc2.5's (Green line) and 2 15" american bass xfl 15's (blue line)... Both the AQ's and AB's are punched into 8.5 cu ft boxes, tuned @ 34 hz... Obviously the sdc2.5's are excelling above the xfl's, but what does this actually mean? I can't imagine that this would mean in that in this particular box the sdc2.5's would be louder. The xfl's are rated to handle at least double the 2.5's... So I guess I'm just confused...



Side note/quesiton..... If you had to choose between these 3 subs, which would you go with.. (amp is hifonics brx2400.

1.(2) 15" AQ sdc2.5

2.(2) 15" American bass xfl

3.(2) 15" American bass XD

I like the xfls for the power handling but I don't know if the brx2400 will push them as much as they'd like... Any opinions on either subject ^^^

Click to read more...

 

[rickymac21 10+ year member]

Well I have been doing some reading and from what I understand this program does not show the projected output of the box/subs. More or less it shows me the efficiency of the subs in the particular box you input, and at what frequency that woofer will perform best?

So correct me if I'm wrong, but according to my graph here, the sdc2.5's will be more efficient than the XFL's pretty much throughout the whole range of frequencies, but in theory the xfl's could/should be louder for the simple fact they can handle more power than the sdc2.5's ???

 

[rickymac21 10+ year member]

Here is another graph... It's Identical to the first one only I added in a pair of 15" American Bass XD's (orange)... The box size is the same with all three lines, but the tuning for the XD's is slightly lower (30 hz vs 34 hz).... The XD's look like they would perform pretty well and be some good sounding subs... But really all three options look pretty solid.. which again just brings to my question from before.. Which will would get louder off the BRX2400 (2000-2400wrms)? XFL's, XD's, Sdc2.5's

 

[Beatin' 10+ year member]

From what I understand, you can't compare subs against each other in winisd.

 

[rickymac21 10+ year member]

From what I understand' date=' you can't compare subs against each other in winisd.[/quote']
Is this a smart*** comment? Or do you literally mean that It's not a reliable way to compare woofers?

 

[Buck 5,000+ posts]

You can't compare subs like that.

 

[Beatin' 10+ year member]

Is this a smart*** comment? Or do you literally mean that It's not a reliable way to compare woofers?

i meant it.

First it doesn't show woofer output losses far above Fb. Second, due to sensitivity ratings being unreliable crap, you can't accurately compare stop-band output of one sub against another in winisd.

 

[rickymac21 10+ year member]

Hmmm, so to decide between the three options I posted, would it simply be based off of what would perform best under my amp? I know there are other factors to take into account, but if each of the subs were placed into their optimum boxes, would the pair that can handle more power (without being underpowered) be the loudest set up? If that's true the XFL's would be the winner right? assuming they can handle a little over rated, lets say 1200w rms, that would make them the best bet? As opposed to using the XD's or Sdc2.5s which would only be able to use 1500-1800w of the 2400w from the amp...

 

[rickymac21 10+ year member]

I'll make this more simple...

which would be best?.

(2) 15" sdc2.5's on brx2400

(2) 15" ab XFL's on brx2400

(2) 15" ab XD's on brx2400

 

[T3mpest 10+ year member]

WiNISD can be fairly accurate if your smart enough to know what your looking at and how it correlates to real world response, along with how the T/S parameters are likely to shift when power is applied. So first things first

1.Your not looking at SPL your looking at gain. This is showing you how peaky the woofer will be vs it's output at it's effeciency baseline. That's why the SDC's seem louder, they are peakier near tuning, probably a lower Q woofer with higher bl/mms ratio. Go to the SPL tab if you want to see output. Then realize the woofer with a 3inch coil vs the 2.5 will probably gain at least 1-2db of SPL advantage that isn't shown on the chart at higher power levels due to power compression.

2.Louder is such a stupid term. No offense, everyone on here does it, but what does "louder" actually mean. Realize any box you make is going to trade bandwidth for effeciency. A box tuned at 45hz will be "louder" on a termlab sensor because you can pick the one frequency your loudest at and that's your score. The higher tuning has lower bandwidth, but higher effeciency. A sub tuned at 28hz, would have a much lower TL score, but would be louder than the 45hz box at a variety of other frequencies, making loud very subjective. Which sub is louder? Depeneds on the frequency Loud on music? Depends on the music. If we play airforces by Jeezy the 45hz box will sound louder, switch to "love your girl" and it's going to get murked by the lower tuned box.

I don't know how many times people bragging about how high their car meters gets into mine and is like "holy crap". No, it doesn't meter anywhere near as loud, despite that fact I've only metered one of my vehicles, ever. However, there is A LOT to be said about having high bandwidth, low distortion and moderate effeciency. You'd be suprised how much louder songs sound like they are when they are reproduced fairly close to correctly vs a vehicle that can spew bass at 148 between 35-50 and that's it. When you can play a 75hz tone with authority and 28hz tone, music overall seems louder since the bass never really lets up.

Looking at the graphs on the XD's have the best frequency response of what you've posted, but that's partially because of the arbitrary boxes you put them in. Pretty sure it's a 2.5inch coil, looks like a weaker motor than the other 2 and the lower tuning is doing it some favors. . Everything else there is far to peaky for my taste, the SDC looks like a fart box. If you drop the tuning on the XFL it would likely have similar response and will outperform it's smaller coiled counterpart. The SDC looks like it could be fun in a 6th order and probably fairly musical as you could balance out the cabin gain quite a bit.

edit: Just saw the XD's were tuned 4hz lower, that's probably playing a part, but I still like that general curve more for daily than the rest. I'm a fan of 30hz tuning or below though for musicality in alot of cases.

 

[bbeljefe]

WinISD shows you how a driver will perform in a box you choose. It assumes a static power and by default, it is one watt at one meter. Of course, it also assumes an anechoic chamber, which is never achievable in an automobile, so the graphs you see are only a reference. Due to cabin gain, the 35 Hz box you build might be resonant at 30 Hz in your particular vehicle. And of course, where you locate the box in the vehicle also has an affect.

All that said, thew graphs are useful in that they give you an idea of how a driver will perform. If your design does well in WinISD, it will also do well in the car, albeit not exactly the same.

As for choosing the subs, I think you're about to get analysis paralysis. The drivers you're looking at are all good drivers. I'd just pick the one you like the best and go with it. ;-)

 

[rickymac21 10+ year member]

Looking at the graphs on the XD's have the best frequency response of what you've posted, but that's partially because of the arbitrary boxes you put them in. Pretty sure it's a 2.5inch coil, looks like a weaker motor than the other 2 and the lower tuning is doing it some favors. . Everything else there is far to peaky for my taste, the SDC looks like a fart box. If you drop the tuning on the XFL it would likely have similar response and will outperform it's smaller coiled counterpart. The SDC looks like it could be fun in a 6th order and probably fairly musical as you could balance out the cabin gain quite a bit.

edit: Just saw the XD's were tuned 4hz lower, that's probably playing a part, but I still like that general curve more for daily than the rest. I'm a fan of 30hz tuning or below though for musicality in alot of cases.

First off, Thank you for explaining it to me in detail.. I just downloaded winisd the other day and really had no idea what I was looking at or how to use it to my advantage (the tutorial won't work on my computer)... So again, much appreciated.

Now as far as woofer choice, I took the tuning from the XFL's and dropped it to 28 hz from 34 and it gave them a pretty flat response there... So seeing that the XFL's are rated at 1000w rms w/3" coils vs the 700w of the XD's w/2.5" coils, the XFL's will come out on top... Looks like the XFL's are gonna be the winners here. . .

Do you happen to know what the XFL's can actually handle though? I've read all types of people saying 1200w, some say 1800w daily... I just want to make sure that If I choose to use the XFL's that they will be sufficiently powered. If not powered to full extent there's a chance the XD's could outperform them no?

 

[T3mpest 10+ year member]

Anything over 800-1000 watts a 3inch coil will generally outperform a 2.5 inch coil. I'd shoot for around a 1500 watt amp. Should be fine. A few hundred watts will literally be inaudible for a daily application. Remember flat response in car won't be flat once cabin gain is applied BUT then you'll have a very good idea of what your cabin gain is like.. So after this, if you have a certain area you want to get louder, you'll know just what tuning changes will make what effect using WINISD. Does that make sense?

 

[rickymac21 10+ year member]

Anything over 800-1000 watts a 3inch coil will generally outperform a 2.5 inch coil. I'd shoot for around a 1500 watt amp. Should be fine. A few hundred watts will literally be inaudible for a daily application. Remember flat response in car won't be flat once cabin gain is applied BUT then you'll have a very good idea of what your cabin gain is like.. So after this, if you have a certain area you want to get louder, you'll know just what tuning changes will make what effect using WINISD. Does that make sense?

I have a better understanding yes. But to be clear, your saying that even though winisd is showing me a flat response now with 8.4 cubes @ 28 hz, my cabin gain will cause my "peak" frequency to change either up or down. But to figure that out I'd have to get my system metered and see at what frequency is the loudest. ??? According to that reading I could adjust the tuning of the box that winisd might show as 'peaky' but in the car it'll be a nice flat response ?

And a question about the coil and wattage statement you made. The AB tnt's have 3" coils like the xfl's, but the tnt's are rated at 800 rms vs 1000rms of the xfl. Assuming my amp puts out rated power (2400 rms @ 1ohm), would it be better to give a pair of tnt's 1200 a piece and get them moving? Or give xfl's 1200 a piece and have them wanting more? To me the tnt's would make more sense because I wouldn have to push my amp to the max and risk clipping the subs, where the xfl's would be wanting to pull more power from the amp. I just don't know.

 

[T3mpest 10+ year member]

Subs don't truly "want" anything. The more power you give a sub the warmer the coil gets and the less effecient and more prone to damage it becomes. If I have a 500 watts amp and can choose a 500 watt RMS sub or 1000 watt rms sub, assuming everything else is equal I'd go for the 1000 watter everytime. The cooler you can keep the coil the better.

And yes that's basically it. Flat in WINISD will not be flat in a car, but it will still probably sound very good. Generally you want extra low end in a car to actually sound "flat" anyways. Plus, if you find one area is lacking, or is too loud, you'll have an easier time in the future, knowing what flat WINISD response sounded like.