GRS 15PF-8 subwoofer not sounding the way i thought it would

I really don't know what to do with this driver now.
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.

Boffle speaker.jpg


For full instructions, download the zip file!
 

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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...
STX is a fine company, so that is already one answer.
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 :) ;)
 
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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.
 
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!
Point is, acoustically you can never get lower than the drivers Qt.
So that will be a Qt of 1.4 in best case
 
Why is it that hornresp gives such diferent results than winisd?

Does anyone have a good formula/program for designing an open baffle system?
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.

It’s also possible the physical driver doesn’t meet its specifications.
 
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.
 
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
 
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)
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.

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.