Your box has suitable dimensions to convert it to Hartley's Boffle. Its open-back box with several layers of felt curtains to absorb the back wave. So it works well with high Qts drivers like GRS.I really don't know what to do with this driver now.
It won't go very deep 40-50Hz maybe, but at least you'll get well balanced response without one-note bump.
For full instructions, download the zip file!
Attachments
STX is a fine company, so that is already one answer.If you have a reference of a 12" in more or less this price range which is ok to take a Linkwitz transform ( sealed so a bit of xmax) and ok quality/price ratio i will happily take advice!
Except for some car dedicated subwoofer ( more than double the price Alpine or Focal bugdet ) i've not found many possible options in EU. There is one STX model but nobody seems to have used it and can give advice about it in here...
Plenty of people on Polish forums talking and using these, google translate is your friend.
Otherwise Reckhorn isn't bad either, or something like Omnes Audio.
Been tested in Hobby Hifi many times.
There used to be Mivoc, but unfortunately, they cut all production for consumers.
Btw, there are also other ways instead of just using a 12 inch 🙂 😉
Another idea - buy a cheap subwoofer DSP and use it to remove that 60 Hz boom (and of course it could be used to a lot more things with that subwoofer).
this one cost just over $60 ...
https://www.parts-express.com/Dayton-Audio-DSP-LF-Low-Frequency-DSP-Controller-230-520?quantity=1
this one cost just over $60 ...
https://www.parts-express.com/Dayton-Audio-DSP-LF-Low-Frequency-DSP-Controller-230-520?quantity=1
I already said that twice or three times 😉
You can already have a DSP for 23 bucks;
https://www.audiophonics.fr/en/dsp-...dsp-module-adau1701-sigma-studio-p-14837.html
Although this doesn't include the programmer.
Which is homemade about 10 bucks or you can order one for 20-25 bucks.
Use a Linkwitz-Transform (with a HP filter) and you're basically done.
A DSP can also be free when a computer/PC is being used.
You can already have a DSP for 23 bucks;
https://www.audiophonics.fr/en/dsp-...dsp-module-adau1701-sigma-studio-p-14837.html
Although this doesn't include the programmer.
Which is homemade about 10 bucks or you can order one for 20-25 bucks.
Use a Linkwitz-Transform (with a HP filter) and you're basically done.
A DSP can also be free when a computer/PC is being used.
Point is, acoustically you can never get lower than the drivers Qt.Your box has suitable dimensions to convert it to Hartley's Boffle. Its open-back box with several layers of felt curtains to absorb the back wave. So it works well with high Qts drivers like GRS.
It won't go very deep 40-50Hz maybe, but at least you'll get well balanced response without one-note bump.
View attachment 1202719
For full instructions, download the zip file!
So that will be a Qt of 1.4 in best case
I wouldn’t yet point blame at WinISD. Davor D achieved your same results by changing 125L modelled enclosure volume to 1250L, so I think it may possibly be a data entry error in your driver file. It might be good to open the driver model and snapshot or post your driver parameters.Why is it that hornresp gives such diferent results than winisd?
Does anyone have a good formula/program for designing an open baffle system?
It’s also possible the physical driver doesn’t meet its specifications.
This woofer works great in an open baffle. I deleted a post accidentally talking about the GRS pro version, which, at least the 12" unit, isn't worth the work.
By the time you get this thing electronically compensated to work in a box you'd probably be be better off with something having over twice the magnet.
winISD has quite some options to enter a wrong unit. Like Meter or Decimeter instead of Centimeter.
This seems the cause in your simulation. A case of garbage in=garbage out. A factor of x10 is pointing into this direction.
Anyway, who ever designed this speaker chassis had no clue what he was doing. No one needs such parameter. Why throw money and work at it, when a better chassis is just around the corner?
The thread starter should explain his idea of an end result. Then there may be something we can suggest, taking into account his location, price range etc.
A DSP is always a good idea with any sub. Someone mentioned a cheap ADAU1701 PCB running on Sigma Studio. This is not for "usual" user, as it has no simple user interface.
This seems the cause in your simulation. A case of garbage in=garbage out. A factor of x10 is pointing into this direction.
Anyway, who ever designed this speaker chassis had no clue what he was doing. No one needs such parameter. Why throw money and work at it, when a better chassis is just around the corner?
The thread starter should explain his idea of an end result. Then there may be something we can suggest, taking into account his location, price range etc.
A DSP is always a good idea with any sub. Someone mentioned a cheap ADAU1701 PCB running on Sigma Studio. This is not for "usual" user, as it has no simple user interface.
Why they don't make this same cheep speaker with a decent Qts is a serious head scratcher. If they did it, what would it cost, an extra 2 bucks? It would probably get insanely popular, which equals sales they ain't gonna get with this thing.
Chinese sales policy. As long as someone imports them to our markets at 4$ a piece, they have no need to change it. China has a history of building copy's that look like a working product, but are not using the right material. Even as this has gotten better over time. This one has a very weak, cheap ceramic magnet and/ or a very large gap for the voice coil. The narrower the gap, the better it works, but this needs low tollerances in machining and a very precise fitting of the membrane. Things that need good tools and skilled worker. The sad thing are the resources and energy that are put into something useless, but who cares about the planet if money is made?
Maybe simulate this one, looks nice for a vented cabinet, not very expensive and you can buy it next door.
https://www.audiophonics.fr/en/haut...00w-4-ohm-90db-40hz-900hz-o305cm-p-15372.html
Maybe simulate this one, looks nice for a vented cabinet, not very expensive and you can buy it next door.
https://www.audiophonics.fr/en/haut...00w-4-ohm-90db-40hz-900hz-o305cm-p-15372.html
This one may fit your cabinet, closed.
https://www.audiophonics.fr/en/haut...00w-4-ohm-92db-19hz-200hz-o381cm-p-15229.html
https://www.audiophonics.fr/en/haut...00w-4-ohm-92db-19hz-200hz-o381cm-p-15229.html
I get to thinking they don't have any interest in people finding out they can buy an actual working 15 for 35 bucks. It would undermine the rest of the industry in which they probably have some interest too, one way or another.
Hmm, with a upper mass corner (Fhm) where T/S theory peters out = 2*Fs/Qts = 31.4 Hz it's truly a 'one note' driver. 😱
You would have a shattered magnet.
It is high Qts driver.
goes in a large box or open baffle.
or bolt it to a wall and the other room is the enclosure.
or bolt it to the ceiling etc etc
It is high Qts driver.
goes in a large box or open baffle.
or bolt it to a wall and the other room is the enclosure.
or bolt it to the ceiling etc etc
If I were in your position, I'd keep the box and buy a GRS 15PT. With 115L & DSP, it could work either sealed or vented. If vented, I'd plan to move the tune up to ~25Hz, which means cutting the ports down to ~30-35cm. Easiest way to start is by plugging the ports & playing with EQ.I was already planning on selling it together with the enclosure on the dutch version of ebay. It is good enouch for some styles of music, but not for my style(s)
That said, the 15PT is only $60 in the US, while you're looking at 100EU. Worth it? How much time, effort, and cost do you have in the box build?
I had a look at the reviews on Partsexpress for this woofer, the GRS PF15-8, and some of the glowing comments make a prime example of what expectation bias and the lack of measuring equipment can really do.
No, there are so many better choices for around 100 euro.That said, the 15PT is only $60 in the US, while you're looking at 100EU. Worth it? How much time, effort, and cost do you have in the box build?
Point is, acoustically you can never get lower than the drivers Qt.
So that will be a Qt of 1.4 in best case
Not true.
In aperiodic systems total system Q can be (and often is) lower than drivers Qts. Like full stuffed TL or box with resistive vent.
Interesting example is "MemBrain" system. Its has acoustic resistor at back or front of the driver, with system Q of only 0,2
See this thread, Boffle is also mentioned.
https://www.diyaudio.com/community/...ject-with-existing-parts.401772/#post-7417363
I dont know about Boffle system Q though.
Felt curtains have some flexibility, they move a bit under sound pressure. So its combined effect of acoustic resistance and mass/spring damping. Not possible to correctly simulate in Hornresp or similar tools.
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