# Search for an 8" sub driver...



## Sonnie (Apr 11, 2006)

I have .47 ft³ of sealed enclosure volume to work with... max depth of 5"... with 400 watts of pure power into to 2 or 4 ohms. This is strictly for music... about 30Hz and up.

I have consider the Tang Band W8-740P and the JBL GTO804 thus far, but nothing decided as of yet.

And one more that looks interesting... Sundown E8 V.2

Looking for possible recommendations and I have not modeled in so long I have forgotten how to do it. If anyone may not accuse me of being lazy and can help... purty please! :whistling:


----------



## GranteedEV (Aug 8, 2010)

I think the JBL is a wicked choice, it's clean all the way up to 400hz and its sensitivity is actually pretty nice.

There are two other drivers I can think of that might work really nicely. One is by Alpine, and the other isn't technically "real".. for all I know it might be vaporware at this point but Kevin Haskins has been working on an 8" Anarchy driver. Then there's pricier drivers from brands like JL Audio and Scanspeak, but we'll just ignore them 

I'll model the JBL and Alpine for ya in a moment.


----------



## Sonnie (Apr 11, 2006)

Thanks! 

I did look at Kevin's 6.5 (or 7") Anarchy and it looks wicked.

Check out the Sundown 8... it also looks pretty wicked, but I do wonder how it sounds. Crazy YouTube on it 



.


----------



## Sonnie (Apr 11, 2006)

I bet that Alpine is the SWR-823D. That looks pretty good.


----------



## GranteedEV (Aug 8, 2010)

That's the one!

Okay, here's what I've modeled. The first pic is the low frequency max / SPL at which the woofer, at 28hz (which is the bottom of the musical spectrum excluding electronik) hits xmax, and the second pic is the max SPL with 400w input (the Alpine is 4 ohm, but the JBL is technically closer to 6 ohm so a bit more info on the amp might help)

JBL GTO 804 (green) - .47 cu ft sealed + 175w will hit xmax = 11.5mm at 28hz
Alpine SWR 823D (Red) - .47 cu ft sealed + 245w
Alpine SWR 823D (magenta) - .47 cu ft + 3X 8" dayton SD215 PE + 225w will hit xsus = 9mm at 28hz

EDIT #3 Graphs attached


----------



## Sonnie (Apr 11, 2006)

Can't do passives with the enclosure I have... it is pre-fab and I can't change it.

Not a whole lot of difference between the R and the GTO is there.

Here's the scoop on the amp... which I will bridge two of the channels for the sub...

High efficiency (greater than 80%) Class D Operation
Xe.load™: optimized for any impedance load
Xe.tune™: 24dB Linkwitz-Riley subsonic and low pass crossovers
Xe.flow™: variable thermal feedback controlled fans
Tried and true triple Darlington output stage
Buffered RCA full range thru output
Remote Monitoring Display (RMD) port
Low Pass Level control ready (LPL-44)
200W x 4 (4-1 ohm stereo)
400W x 2 (8-2 ohm bridged)
Built-in Crossovers
Optional Remote Voltage Display
Optional Remote Low-Pass Level Control
Variable input sensitivty
0 - 18dB Bass Boost at 45Hz
CEA-2006 Compliant


----------



## GranteedEV (Aug 8, 2010)

It sounds like a car audio amp. 

That sundown looks interesting.


----------



## Sonnie (Apr 11, 2006)

Exactly... it is a car audio amp. :bigsmile:


----------



## sparky77 (Feb 22, 2008)

I'm running two of the Tangband w8-740p's in my HT, in sealed enclosures and they produce some serious bass in a room thats 14' x 20', I can imagine what they would do in a vehicle. I plan to put one the trunk of my car soon to find out. And you'll only need 100 watts to peak one out.


----------



## Mike P. (Apr 6, 2007)

> 24dB Linkwitz-Riley subsonic and low pass crossovers


Foe the subsonic filter, does the amp have selectable specific frequencies or a range of frequencies?


----------



## Sonnie (Apr 11, 2006)

It is selectable from 40-400Hz:


----------



## Mike P. (Apr 6, 2007)

Green is the Tang Band, yellow is the JBL and orange is the Sundown. All with 200 watts and no hi-pass filter. Excursion isn't a problem down to 20 hz.


----------



## Sonnie (Apr 11, 2006)

Can we add the Alpine in there... I am really favoring it for some reason.

I guess the Tang is the better of those huh, since it does better in the 50-80Hz range?


----------



## Mike P. (Apr 6, 2007)

Grant, can you post the Alpine driver file please?


----------



## GranteedEV (Aug 8, 2010)

Here ya go, and yeah, it's the one i'd favor too, alpine really hit the engineering out of the ballpark... high excursion, low inductance, nice flat BL curve, reasonably shallow mount, and I think the cone looks purdy too 

I'd bet the tang band is very nice, _but_ I don't know how accurate the T/S Paramters are... i've heard that their T/SP can sometimes be pretty off.


----------



## Mike P. (Apr 6, 2007)

> I'd bet the tang band is very nice, _but_ I don't know how accurate the T/S Paramters are... i've heard that their T/SP can sometimes be pretty off


I agree, I remember when the W8-740C was measured and it was no where close to the published parameters.

​
Red is Alpine, yellow is JBL and green is Tang band. Each shown with the power input it would take to reach Xmax at 30 hz. The Alpine would be my choice.


----------



## bambino (Feb 21, 2010)

In my opinion you won't be dissapointed with the Alpine weather it be the Type R or Type X (which is what i have and would consider).:T


----------



## Sonnie (Apr 11, 2006)

Yeah... I think it will be the Alpine. I think I would like to try out the Anarchy once Kevin gets it ready. I may also pickup the Tang Band and give it a whirl at some point.


----------



## GranteedEV (Aug 8, 2010)

Sonnie said:


> Yeah... I think it will be the Alpine. I think I would like to try out the Anarchy once Kevin gets it ready.


I think he said it'll have 18mm of xmax :dumbcrazy:


----------



## Sonnie (Apr 11, 2006)

Can one of you guys tell me the perfect sealed box for this Orphan 8" driver?



Qts - 0.405 
Qes - 0.442 
Qms - 4.778 
Fs - 34.289 Hz 
Re - 5.25 Ohm 
Ls - 12.16mH 
Lp - 4.053 mH 
Rp - 25.46 Ohm 
Vas - 5.031 L 
Mms - 214.1 g 
Cms - 100.6 m/N 
Bl - 23.39 T*m 
Sensitivity - 78.44 dB 
17mm Xmax

It absolutely slaughters the Alpine unit, so I plan to use it, but I have to modify the box a little to get it to fit better in the truck. I am working with about .2 to .3ft³... and would like to get it exact for a sealed enclosure. I figure since I am going to modify it... may as well maximize the potential it has with the perfect sized enclosure. 

I am working with about 500 watts from a JL Audio HD900/5 (I had to send my other amp in for repairs). The JL is rated at 500W RMS x 1 @ 1.5-4Ω (11V - 14.5V). So with this being a 6Ω driver... not sure what the real power would be. I am also using the 24dB/octave at 30Hz infrasonic filter on the amp.

Thanks!


----------



## Mike P. (Apr 6, 2007)

Here are .1, .2, and .3 cu.ft. box volumes and the associated Q values. Shown with 300 watts input power which is estimated what you'd get from the amp. No infrasonic filter applied as it's not needed.


----------



## Sonnie (Apr 11, 2006)

Hmmm... well I can definitely bottom it out right now and it is in a .23ft³ box (I will double check that later today). I must be getting more than 300 watts to it. Of course it is pretty loud before it bottoms... and I will check that as well later today with my SPL meter.


----------



## Mike P. (Apr 6, 2007)

Do you have any boost applied to it at some frequency? Assuming the parameters are correct modeling shows Xmax at 11 hz with 500 watts in a .23 cu.ft. sealed box.


----------



## Moonfly (Aug 1, 2008)

Have you got the driver file Mike?


----------



## Mike P. (Apr 6, 2007)

Here you go:

View attachment Sound Splinter Orphan 8.wdr


----------



## Moonfly (Aug 1, 2008)

Cheers. I'll have a play with the model for myself, but probably wont add anything to this thread unless required to do so. It is strange it is bottoming out though, because according to the model it shouldnt be, even with the full 300 watts. Perhaps adding in a HPF might help?


----------



## Sonnie (Apr 11, 2006)

No boosting... although the song might be naturally heavy in a certain frequency.


----------



## Moonfly (Aug 1, 2008)

Is there any problem with the set of parameters we have for this driver then. We could work out something like the system Q of this by hand, then see if it tallies up with what WinISD is reporting, which might show errors in the parameters if there is a significant difference.


----------



## Sonnie (Apr 11, 2006)

I would have no idea myself. I am guessing they got it right... as it has been around for a while. Mike designed it to be in a 10" x 10" cube with a passive radiator, so sealed is not what it was optimized for, although it seems to work very well in a sealed enclosure. 

I remeasured my enclosure and it is actually .18ft³ net.


----------



## Moonfly (Aug 1, 2008)

The models arent usually far out at all, so its strange if you seem to be having issues. Are you positive its bottoming, and not something simple like cables contacting with the rear of the driver under heavier excursion. I know its obvious but it does happen. There is also the point that it is only an 8" driver, so hitting its limits wont actually be all that hard. You could also try reducing the internal volume a touch, so the driver can suck more power and have less excursion. It will raise the system Q a bit, which might not be to your taste, but no no harm in trying it. Obviously the low end would reduce a touch but the sub would have a bit more impact, if it helps solve your issues though it may well be preferable.


----------



## Sonnie (Apr 11, 2006)

It is definitely bottoming. I have the speaker wire pulled tight. I only have it at about 3/4 power too... the amp has more to offer the sub... and it is seriously loud. I really want to put the RTA on it so I can see how low it is hitting now. I don't think it would hurt to make it a tad smaller and test it, although I am not sure why I would need it any louder than it is other than to make my ears bleed. I could probably get it as small as .13ft³ net.


----------



## fusseli (May 1, 2007)

Orphan 8 sealed in 0.18cuft and 300W, checks out golden in Jeff bagby's Box Designer software, should be nowhere near xmax.


----------



## Moonfly (Aug 1, 2008)

WinISD reports the same thing. Displacing some volume in the box some how, with some sort of blocks, is more about making the driver move less and suck up more power from the amp than making it louder. Do you have any way of testing the TSP's Sonnie, its not unheard of for a driver to slip through that doesnt match the published TSP's. I think it may be worthwhile given that two different software programs are saying the same thing, and it seems the driver isnt performing anything like close to whats modelled.

I do suspect however, that the smaller box wouldnt be to your liking, which would be a negative of reducing the cabinet size.


----------



## Sonnie (Apr 11, 2006)

Maybe the amp is putting out 450-500 watts due to its design. It is rated at 500 wrms from 1.5-4Ω ... maybe that extends farther and the power does not drop that much at 5.35Ω. :huh:

I ordered the Dayton Audio WT3P WT3 Bundled with Precision Scale ... since they were throwing in the scale for the same $99 price tag. It might be handy to have around to piddle with testing all along.

A smaller box is not a big deal... it can be just big enough to hold the driver and it would be fine by me.

So... at 300 watts the programs say that it should be outputting 103db SPL? I will test it on my way to work today and see what levels I get. That might help determine the power it is getting.


----------



## Moonfly (Aug 1, 2008)

That would make more sense but even with 500 watts the model still says it should be ok and not really going over xmax. Max spl would be 105db with 500 watts at about 45hz, at 20hz it would be about 95.


----------



## fusseli (May 1, 2007)

Moonfly said:


> That would make more sense but even with 500 watts the model still says it should be ok and not really going over xmax. Max spl would be 105db with 500 watts at about 45hz, at 20hz it would be about 95.


Ya even at 500W it should be fine. The mechanical excursion limit should be a bit beyond xmax even, so bottoming out in such a small box is a little strange.

Sonnie, are you 100% sure there is no bass boost or low EQ being applied anywhere?


----------



## Sonnie (Apr 11, 2006)

100% positive... EQ is flat and "0" on the Bass Boost.

You know what... I do have Loudness set at "Mid"... but I was thinking that only effected the output at lower volumes. I will set that to "Off" and see if it makes a difference.

I was hitting between 121 and 122db on the way to work. Those were mainly bass notes on I'm Not Afraid - Fleetwood Mac ... I am guessing 50-70Hz. Of course that accounts for cabin gain, which I am not sure how that would relate to the SPL in the programs.


----------



## fusseli (May 1, 2007)

Ya unless you know the impulse response of the listening area (your car) and a distance from the sub, it's pretty tough to infer actual delivered power based on measured SPL.

120dB+ sure is sweet off of an 8" sub though isn't it?  I love my JL 8W7 for the same reason...


----------



## Mike P. (Apr 6, 2007)

What head unit are you using?


----------



## Moonfly (Aug 1, 2008)

Sonnie said:


> 100% positive... EQ is flat and "0" on the Bass Boost.
> 
> You know what... I do have Loudness set at "Mid"... but I was thinking that only effected the output at lower volumes. I will set that to "Off" and see if it makes a difference.
> 
> I was hitting between 121 and 122db on the way to work. Those were mainly bass notes on I'm Not Afraid - Fleetwood Mac ... I am guessing 50-70Hz. Of course that accounts for cabin gain, which I am not sure how that would relate to the SPL in the programs.


Cabin gain can be as much as +10db in something like a car. Loudness in a car usually isnt dynamic, it could be but if it isnt the loudness correction would be a simple broadband correction curve applied to the entire frequency range which would be the same at any volume level. That in itself could explain some of the issues. It does sound like you have a good strong amp at work as well.


----------



## Sonnie (Apr 11, 2006)

I would like to use one of those JL W7's... but no way to mount it with that extreme depth it has. I can accommodate a max driver depth of about 6 inches.

The headunit is a Pioneer AVH-P3300BT.


----------



## Sonnie (Apr 11, 2006)

Uh... yup... the "Mid" loudness level adds quite a bit of bass to the mix... +10db. It sure sounds better... as long as I don't crank it really loud.


----------



## fusseli (May 1, 2007)

Sounds like your amp must be meeting the power demand nicely of a +10dB static gain haha


----------



## Moonfly (Aug 1, 2008)

Also sounds like its simulating a higher Q sound :T I would also consider that a better sound than the .5 Q of this sized cabinet.


----------



## Sonnie (Apr 11, 2006)

WT3 results for the SoundSplinter Orphan 8 vs. factory parameters:

Qts - 0.491 vs. Qts - 0.405
Qes - 0.523 vs. Qes - 0.442
Qms - 8.129 vs. Qms - 4.778
Fs - 37.68 Hz vs. Fs - 34.289 Hz
Re - 4.903 Ohms vs. Re - 5.25 Ohm
Ls - 13.8mH vs. Ls - 12.16mH

A few of these are considerably different.

No parameters tested for the following:

Lp - 4.053 mH
Rp - 25.46 Ohm
Vas - 5.031 L
Mms - 214.1 g
Cms - 100.6 m/N
Bl - 23.39 T*m
Sensitivity - 78.44 dB
17mm Xmax

I tried the Vas test via Test Box Method, but my .27ft³ was too big. I have a .095ft³ box (net with driver) built, but have not had a chance to test it yet.

I will test it again and try the test box as well... maybe later on today.


----------



## Moonfly (Aug 1, 2008)

When you get the Vas figure we can try a model with your new parameters and see how different they look, should be interesting.


----------



## Sonnie (Apr 11, 2006)

Hmmm... now I am wondering just how accurate this WT3 is. I retested the driver today and got different parameters:

Re = 4.988
Fs = 39.03
Qts = 0.482
Qes = 0.526
Qms = 5.852
Le = 13.88

I performed the Vas test and it gave me a result of .064 Cu Ft the first time.... could not get it to register for me a second time... telling me the box was too big. :huh:


----------



## Binary (Nov 23, 2009)

the wt3 is very accurate sonnie, Changes in temperature/Humidity will affect your TS/Parameters. Why not use the added mass method of finding vas?


----------



## Sonnie (Apr 11, 2006)

Yeah... I could try that method, but was not sure exactly how to go about adding the mass and how much to add, etc.


----------



## Binary (Nov 23, 2009)

I believe you just weigh out a known mass of play doh, add it to the cone, run the application and tell it what you added. It should tell you the rest.


----------



## Sonnie (Apr 11, 2006)

Well.... I got the free scales, so I suppose I could roll up a small bit of the Dynamat, weigh it and stick it to the center of the speaker (no play-doh in the house).


----------



## Binary (Nov 23, 2009)

That should work. As long as it's tacky. Go for it!


----------



## Sonnie (Apr 11, 2006)

I'll give it a try on Wednesday... my day off.


----------



## FLAudioGuy (Sep 21, 2011)

Sonnie, I don't have my engineering software going right now but just looking over your supplied TSP's by eyeball, they don't seem to add up to me. When using either delta-mass or delta-compliance Vas measurements make sure that you get a new impedance peak that is significantly higher (compliance method) or lower (mass method) so the software curve fitter can easily distinguish and get proper values. Also, make sure you use enough drive level to actually move the cone. Very low levels produce inaccurate results.

In regards to the 'bottoming' noise: Check the tinsel leads to the cone are not being stretched taut and pulling the coil off center. I would also use a strobe to check the surround. On some drivers that use poorly designed/implemented surrounds, they can get 'sucked in' (especially on very small enclosures) as the cone moves forward and make a snapping sound similar to a coil hitting the backplate or spider/cone joint hitting the top plate.


----------



## Sonnie (Apr 11, 2006)

I am not sure how to increase the volume with WT3. The "Level" setting they recommend is "1" under Sound/Recording. The volume level is full volume during the test.

I have not heard any noises since using the smaller box and since turning the Loudness off.


----------



## Sonnie (Apr 11, 2006)

Welp... did not get a chance to do this yesterday. We ended up having to fix some drainage issues and then after trimming trees and shrubs all afternoon, I was exhausted. So... at present the wife and I are in Gatlinburg, Tennessee and won't be home until late Sunday evening. Looks like it may be next Wednesday before I will have another chance to test it. :huh:


----------

