I don't have access to windows to run any of the modeling software. Is there any option for mac OSX? I kinda hate just asking for people to do designs for me, but don't really have the skills/knowledge/software to do it myself.
I am looking the best options for a high WAF design for the GW-212 because I have a couple of them laying around and my wife wants bass to supplement some DML panels I built for her in her. Hoping for something like 40hz - 200 hz.
I am looking the best options for a high WAF design for the GW-212 because I have a couple of them laying around and my wife wants bass to supplement some DML panels I built for her in her. Hoping for something like 40hz - 200 hz.
This it? https://www.parts-express.com/Goldwood-GW-212-4-12-OEM-Woofer-4-Ohm-290-330?quantity=1
PE suggests 2ft^3 sealed. F3 @48.7 Hz.
jeff
PE suggests 2ft^3 sealed. F3 @48.7 Hz.
jeff
Yes, that is the one. I just didn't know if the PE recommendation was close to optimal or if there were better options.
Qts = 1.2
If you aren’t using it on an ob, the receipe for this kind of driver is as large a box as you can live with and make it aperiodic.
dave
If you aren’t using it on an ob, the receipe for this kind of driver is as large a box as you can live with and make it aperiodic.
dave
+1. PE neglects to mention the giant peak in the fr response centered around 75-80Hz in their box.
jeff
jeff
Hmm, FWIW HR 'says' ~68 Hz with a ~ +8 dB peak, so still horrible of course! 
😱
As for desired BW, we ideally want the box to control up to the desired upper mass corner (Fhm) or at least 2 - 300 Hz, though with a ~ 2*35.8/1.2 = ~58.3 Hz it can't even control its Fs very well, hence really only useful for huge VLF horns, OBs.
😱As for desired BW, we ideally want the box to control up to the desired upper mass corner (Fhm) or at least 2 - 300 Hz, though with a ~ 2*35.8/1.2 = ~58.3 Hz it can't even control its Fs very well, hence really only useful for huge VLF horns, OBs.
If you want a short and solid answer: Get rid of these drivers (don't know how many a couple are) at eBay and get anything else.
These drivers are not suited for any HIFI cause. Sorry if this may sound rude.
Then describe what you expect and what you are willing to spent, money and work wise. Some nice and knowing people here will sure help you to find a solution, tailored for you and Wifey.
I can instantly think of about 500 better ideas than using such a driver which is physically not able to reproduce a clean signal.
A short explanation: A higher qts than .7 is to be avoided in any quality sound reproduction HIFI and PA, very rare, exotic exceptions excluded. A QTS of 1.2 is just a bad joke! Usual, simple to use drivers for vented and closed cabinets may have a QTS between .25 and .55 even an open baffle should stay below .8
These drivers you got are made to impress unknowing DIYS people with huge size and low price, even as they are hugely overpriced at 40US$. Just to give an answer, even before you ask but "why do they build them this way if they don't work."
Also keep in mind, there are regions of this world where local music does not need high quality reproduction, just has to be very loud and the hardware dead cheap. Add an even cheaper horn and you are good to go...
These drivers are not suited for any HIFI cause. Sorry if this may sound rude.
Then describe what you expect and what you are willing to spent, money and work wise. Some nice and knowing people here will sure help you to find a solution, tailored for you and Wifey.
I can instantly think of about 500 better ideas than using such a driver which is physically not able to reproduce a clean signal.
A short explanation: A higher qts than .7 is to be avoided in any quality sound reproduction HIFI and PA, very rare, exotic exceptions excluded. A QTS of 1.2 is just a bad joke! Usual, simple to use drivers for vented and closed cabinets may have a QTS between .25 and .55 even an open baffle should stay below .8
These drivers you got are made to impress unknowing DIYS people with huge size and low price, even as they are hugely overpriced at 40US$. Just to give an answer, even before you ask but "why do they build them this way if they don't work."
Also keep in mind, there are regions of this world where local music does not need high quality reproduction, just has to be very loud and the hardware dead cheap. Add an even cheaper horn and you are good to go...
High Qts
So open baffle is a option.
helps with what would be a very large box.
Real trick is very wide baffle for better bass.
For sealed in a enclosure.
Take a big guess the PE sim is silly.
2 cubic feet would be seem like very
high Qtc. To get somewhere flat
assume 3 to 5 cubic feet.
But why guess, can do a quick breakdown
in sim. with what im guessing 1 to 1.5 Qtc
being feasible with large box.
Great thing about high Qts low cost.
Everyone will peeve and poo pee doo.
about them.
Find a decent trade off and run them
LOL.
far as i remember, data sheet says
280 to 300 liters was what it was tested
at. about all yah get.
open baffle very feasible.
So open baffle is a option.
helps with what would be a very large box.
Real trick is very wide baffle for better bass.
For sealed in a enclosure.
Take a big guess the PE sim is silly.
2 cubic feet would be seem like very
high Qtc. To get somewhere flat
assume 3 to 5 cubic feet.
But why guess, can do a quick breakdown
in sim. with what im guessing 1 to 1.5 Qtc
being feasible with large box.
Great thing about high Qts low cost.
Everyone will peeve and poo pee doo.
about them.
Find a decent trade off and run them
LOL.
far as i remember, data sheet says
280 to 300 liters was what it was tested
at. about all yah get.
open baffle very feasible.
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It is not that much about cost, but construction. There are quite nice low priced drivers out there. You only have to find the pearls. Recently I got a pair of new, well made, steel chassis 18" drivers for 45€ each. The seller still made money on them... PE has gotten quite expensive recently, here in Germany the Dayton Audio products are even 1/3 more expensive now. Better alternatives out there.
Qtc for sealed box from 1.4 , 1.5 and 1.6
10 cubic feet / 283 liters Qtc 1.4
8 cubic feet / 226 liters Qtc 1.5
5.5 cubic feet / 156 liters Qtc 1.6
5 to 5.5 cubic feet sealed about as high as I
would take Q
10 cubic feet / 283 liters Qtc 1.4
8 cubic feet / 226 liters Qtc 1.5
5.5 cubic feet / 156 liters Qtc 1.6
5 to 5.5 cubic feet sealed about as high as I
would take Q
I appreciate the frank comments and help. My wife is not super into hifi. She wants bass to supplement the DMLs I built her, but doesn't want to take up a large space in her room. She doesn't really know any more than the DML panels are not adequate bass.
I don't want to waste time trying to force a square peg into a round hole, so I may just abandon these GRS woofers. What would you all do for this case?
I don't want to waste time trying to force a square peg into a round hole, so I may just abandon these GRS woofers. What would you all do for this case?
Full space open baffle sim.
Floor included.
listening position likely to be up high.
Smallest I would go is 496mm x 800mm baffle.
Flattest response driver center mounted
248mm x 360mm
Floor included.
listening position likely to be up high.
Smallest I would go is 496mm x 800mm baffle.
Flattest response driver center mounted
248mm x 360mm
For a beginner a closed box is a sure bet. Maybe consider this one, with a very reasonable price.
https://www.parts-express.com/GRS-1...r-Surround-Subwoofer-4-Ohm-292-820?quantity=1
A clever, cost limiting design doing anything right.
Just one of them in a 1.5-2.0 sqft box should make you a very good sub, not easily matched by commercial products. You don't need two of them, just one placed near the middle of the main speaker. You sure need an amp for it with included x-over, you know that?
https://www.parts-express.com/GRS-1...r-Surround-Subwoofer-4-Ohm-292-820?quantity=1
A clever, cost limiting design doing anything right.
Just one of them in a 1.5-2.0 sqft box should make you a very good sub, not easily matched by commercial products. You don't need two of them, just one placed near the middle of the main speaker. You sure need an amp for it with included x-over, you know that?
And that’s an option for a WAF box?
The WAF solution is to pitch it, and buy something expensive that works well in a small box. If she’ll let you spend the money.
Iam working on a FAST/WAW project. Funds are limited, so plan is to use affordable driver with high Qts. So I found a solution based on Visaton Solo 50 cabinet which allows fairly small box with such drivers. Two chambers tuned and damped in such a way that unwanted peak is reduced and distributed over wider range.
This is Hornresp sim with Goldwood driver in question, box net volume is around 90 Liters (3,2 cuft). Sim shows in following order: general data, schematics and damping, response, impedance. Impedance peak of only 7 ohms clearly shows aperiodic nature of the system.
If we take 92dB as a reference, there is 3dB gain between 50-120Hz, F3 is 39Hz with 2nd order rolloff like closed box. F10 is around 27Hz.
If you wish to try this, tomorrow I can post some quick drawings and details of possible box construction.
This is Hornresp sim with Goldwood driver in question, box net volume is around 90 Liters (3,2 cuft). Sim shows in following order: general data, schematics and damping, response, impedance. Impedance peak of only 7 ohms clearly shows aperiodic nature of the system.
If we take 92dB as a reference, there is 3dB gain between 50-120Hz, F3 is 39Hz with 2nd order rolloff like closed box. F10 is around 27Hz.
If you wish to try this, tomorrow I can post some quick drawings and details of possible box construction.
interesting.
fill or absorption contributes a lot
to that.
little twist to approach things,
creative. with the wizard would be easy
to observe behavior on how those chambers
work.
Kind of the fun with sealed high Qts.
my approach was absorption too.
Big box and stuff it silly.
fill or absorption contributes a lot
to that.
little twist to approach things,
creative. with the wizard would be easy
to observe behavior on how those chambers
work.
Kind of the fun with sealed high Qts.
my approach was absorption too.
Big box and stuff it silly.