Hey Audiophiles! I plan to make a sixth order bandpass housing a 15inch subwoofer. Sealed side will be around 1cube, port side I'm only going for 2 CF. I would use WINISD but all it does is crash anytime I put in TS parameters. Speakerbox pro doesn't have this option as far as PRs-only ports. Anyone with experience making one of these? What I like the sound of PRs and I am not sacrificing my whole trunk making slots, aeroports, or extra wood / weight to go that route. Thanks in advance!
Virtuix cad has enclosure calculator.
I use older alpha pro version of winisd.
no crashing on windoze 10
just need driver datasheet to sim
and passive
usually want double the radiator for driver size.
so 2x radiator for sub.
Bur have seen newer radiators with lots of travel
and mass for sub use
I use older alpha pro version of winisd.
no crashing on windoze 10
just need driver datasheet to sim
and passive
usually want double the radiator for driver size.
so 2x radiator for sub.
Bur have seen newer radiators with lots of travel
and mass for sub use
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If one side is sealed it's a 4th order bandpass.
You could try a workaround by first simulating the bandpass with port.
then make an auxiliary calcularion of a bass reflex with port exactly as used in the bandpass box.
then simulate a PR box with same volume as bass reflex and adjust the PR ( changing PRs or adjusting added weigth) to match the tuning to the bass reflex.
That should be your PR. Keep in mind that with a PR you can always change the tuning by changing added weigth.
Thanks for the responses! I will download Virtuix. My brain went left when I was typing the original post-hence 'sealed side'😆 I will let you know how it goes👍👍👍
I have 2 Earthquake SLAPS15v2 PRs as well as 2 Earthquake SLAPS12. The xmax is 4inches on the 15s and 3 inches on the 12 PRs. I have been told that the 12 version works very well with 1 15 driver. No weights with my models. The 15PR is 13hz and the 12PR is 17hz. Thanks again audiophiles! All info appreciated🫡
https://www.hometheatershack.com/th...detailed-guide-on-how-to-use-winisd-pro.6330/
Try inputting in this sequence in bold:
This is the recommended method for entering driver parameters [if at any point you need to change the unit of a parameter simply click on the displayed unit and it will change]:
- Enter Mms and Cms which results in Fs being calculated. If Mmm and Cms are not known enter Fs. If Fs and Mmm or Cms are known enter Fs and the other known value.
- Enter Sd, Bl and Re. This will result in more auto calculations being made, but Qms and Qts will be blank. If Re is not available, go ahead and enter Sd and Bl.
- Enter either Qms or Rms, whichever is available, generally Qms is available.
- If Mms and/or Cms were not provided for input, now input Qes. This will cause some other fields to auto calculate.
- Enter Hc, Hg and Pe if available. These are not required, however Pe (RMS Power Rating) will give a good idea of how much power signal input to model with.
- Enter the number of voice coils. NOTE: Drivers using dual voice coils may cause the Bl and Re parameters to change when changing the connection wiring from parallel to series. Be sure to monitor these when changing the connection option, but WinISD should automatically change these values properly.
- Correct Znom (nominal impedance) if needed. Many times this will change to 6 and should be 2 or 4... or the ultimate resistance (in ohms) you intend to run based on the voice coil configuration and your connection setting (parallel or series).
- Enter Xmax and any other missing parameters if known and continue. DO NOT change any of the blue auto calculations. If they are only slightly different, this is okay. If they are off significantly, contact the manufacturer or vendor of the driver.
Note that me and a few others loaded 'tons' of drivers to WinISD, so for folks wanting old driver specs, maybe worth searching these: https://www.hometheatershack.com/threads/downloadable-winisd-pro-files.14410/
PRD,
When you are entering parameters into any program, be aware that Earthquake uses "Xmax" incorrectly in two ways:
Xmax (Maximum linear excursion) is one way excursion, not peak to peak.
A driver with an Xmax of +/- 4 inches (101.6mm) would have a minimum of 8 inches (203.2mm) peak to peak travel, obviously impossible for the SLAPS15v2 with it's 4.56" overall depth. The SLAPS15v2 has (at most) an Xmax of 1/2 of 4.5", 2.25" (57.15mm) still impressive, and OK for use with a 15" driver with a bit under half that excursion.
A passive radiator's travel can be linear nearly up to it's mechanical limits, so "Xmax" is often used instead of "Xlim" or "Xmech", the mechanical limit at which no more travel is possible without damage.
In the case of their drivers, they are mistakenly substituting "Xmax" for "Xlim" or "Xmech".
"Maximum linear excursion" (Xmax) can be calculated many ways, but for "audiophiles" Xmax is the one-way peak excursion which produces 10% THD of the current waveform when driven at FS, the free air resonant frequency.
Simply put, Xmax is the range of motion the cone can move and still be controlled linearly by the magnet structure. The further the voice coil is pushed out of the magnetic gap, the more power is wasted as heat and distortion.
The Earthquake HoLee S-15 claim of a four inch (peak to peak...) Xmax with a coil winding height of "over 3 inches" would amount to no more than 3" of peak to peak before the coil is pushed completely out of the magnetic gap, at best a 38mm Xmax.
Good luck with your cabinet design!
Art
@weltersys big thanks to you. I can put Earthquake company in the same league as all these other manufacturers now with this in terms of deceptional marketing🫡
Since you don't have mass adjustments on your PRs, volume adjustments will change your tuning. Smaller = higher Fb.
That would be good wouldn't it? 13hz and 17hz is way low. Still trying to decide if I want to use the 12PRs or 15PRs but thanks for that @wolfteeth!
The QTS is 0.46. A lot of feedback has been "don't do it!" Or, "Gonna have to look at trade-offs" Over on other forums so far😆 So I will keep this in my back pocket, wait until I buy another subwoofer with a Qts of .6 or .7
On the other hand even though I initially made a mistake and said 'sealed side', it looks like a 4th order would better accommodate this Subwoofer. So, Will update as this build comes along!
On the other hand even though I initially made a mistake and said 'sealed side', it looks like a 4th order would better accommodate this Subwoofer. So, Will update as this build comes along!
I can give feedback on 6th order bass sytem.
Usually it's told that 6th order has bad transients and sounds mellow (Greetings from Bose).
I have 6th order bass with double voice coil with reflex ports and 6 inch driver and it sounds quite good in a 2.1 system. No feeling of bad transients.
So I know also this system can sound good if well implemented.
Usually it's told that 6th order has bad transients and sounds mellow (Greetings from Bose).
I have 6th order bass with double voice coil with reflex ports and 6 inch driver and it sounds quite good in a 2.1 system. No feeling of bad transients.
So I know also this system can sound good if well implemented.
Indeed! This vented cab (measured 20 Hz Fs woofers) was originally laid on its side (sans HF horn of course!) and positioned diagonally 'firing' into the corner, creating conical horn vent 'gaps' on each side with a 56" wide mid horn perched on top to seal it off as a 6th order BP with a roll of insulation stood upright in the corner 'V' for fine tuning.
As a 120 Hz XO stereo pair they were pretty freaking awesome for the times (late '70s), though considering the limited LF in all but a few special recordings and no measurements, guessing they might not 'measure up' by today's standards unless limited to 60-80? Hz.
Still, believe basic 6th order and not just tapped variants, when properly done is fine for HT and a viable option for some HIFI apps.
As a 120 Hz XO stereo pair they were pretty freaking awesome for the times (late '70s), though considering the limited LF in all but a few special recordings and no measurements, guessing they might not 'measure up' by today's standards unless limited to 60-80? Hz.
Still, believe basic 6th order and not just tapped variants, when properly done is fine for HT and a viable option for some HIFI apps.
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The 6th order bass system began "to sing" after putting out the passive network and drive it actively with a small 2.1 amp. This gave more control.
And using CD quality source with known music showed me - it sounds pretty good in the bass. Listening to radio stations on this small amp could not help as radio music is heavily processed soundwise. What you hear is fat voices from the speakers.
And the matching to the satellites had to be managed. Without that it's difficult to hear subjectively the absolute quality of a bass system.
Still dont know what woofer.
But overall if you cant control the mass of the passives.
Add/ remove weight.
Most the deciding factor will be which pair will
get desired tuning.
Your essentially designing 4 th order bandpass.
As with passive radiator the actual cut off of the transfer
function is sharper.
Virtuix Cad has 4th order with passive radiator calculator.
But overall if you cant control the mass of the passives.
Add/ remove weight.
Most the deciding factor will be which pair will
get desired tuning.
Your essentially designing 4 th order bandpass.
As with passive radiator the actual cut off of the transfer
function is sharper.
Virtuix Cad has 4th order with passive radiator calculator.
@WhiteDragon Oppsie! Its a GonzoJr 15. One of the first built by Robotunderground. The box I designed and built. 2.5 cf net aroumd 5.5-6 gross volume. Used two EQ Pump-12s and the output is nearly insane with 1750w @1ohm for 1 15.
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I think there is much truth in this statement 😉 ........ on the other hand, that aside, Earthquakes drivers and PRs are quite impressive and good value for the money, especially as they most of the time have a sale on both drivers and passives.
Just don't use their Xmax values in calculations .... derive your own
And I would like better that Earthquake just listed the right values, as they are good enough as is, and would build a more trustworthy company image