Hi there! I am new here and I will try to be precise with my wording. The plan is to build a subwoofer for my home theater. It'll be the Mivox XAW 320HC
It seems that it has the possibility to add several weights to it which changes the response quite a bit. What would your choice be? I am not sure what tuning frequency would be good but I would have no problem building a 200liter enclosure!
Thank you!
It seems that it has the possibility to add several weights to it which changes the response quite a bit. What would your choice be? I am not sure what tuning frequency would be good but I would have no problem building a 200liter enclosure!
Thank you!
Greets!
1st law of speaker design: 'One is always trading efficiency [n0 or eff] for bandwidth'.
From the chart, adding mass lowers Fs, ergo efficiency [power handling] is falling in step with Fs..........
2nd law: 'As box compliance [Vas] increases and/or effective motor strength decreases [increasing Qts'], box volume [Vb] increases': Hoffman’s Iron Laws of Speaker Building: TA Speaker Topics: Loudspeaker Design Tradeoffs
Qts' = Qts + any added series resistance [Rs]: HiFi Loudspeaker Design
3rd law: 'The room dominates!'
room modes - Google Search
For Optimum Sound, How Many Subs, and Where Do You Put 'Em? | News & Views | Ohm Speakers | Custom Audiophile Speakers for Music & Home Theater
There's more of course, but for now the most important ones for you + any personal reasons/preferences yet stated, so only you can decide which to choose.
Otherwise, my default recommendation is don't add any mass since it will make it too heavy relative to its effective motor strength, so would ideally need to be tuned below Fs, which at ~23 Hz is close enough to the THX 20 Hz reference in room.
Of course there's hundreds of movies with true infrabass [<20 Hz], so may want to add mass if/once 'we' know more about the room, any limitations such as neighbors, etc.: The Ultimate List of BASS in Movies w/ Frequency Charts | AVS Forum
That said, unless this brand is known to publish accurate enough specs, then most likely the motor will be weak enough to need to be tuned below Fs, so between the room, driver, unknowns, best to measure both with REW or similar: https://www.roomeqwizard.com/
GM
1st law of speaker design: 'One is always trading efficiency [n0 or eff] for bandwidth'.
From the chart, adding mass lowers Fs, ergo efficiency [power handling] is falling in step with Fs..........
2nd law: 'As box compliance [Vas] increases and/or effective motor strength decreases [increasing Qts'], box volume [Vb] increases': Hoffman’s Iron Laws of Speaker Building: TA Speaker Topics: Loudspeaker Design Tradeoffs
Qts' = Qts + any added series resistance [Rs]: HiFi Loudspeaker Design
3rd law: 'The room dominates!'
room modes - Google Search
For Optimum Sound, How Many Subs, and Where Do You Put 'Em? | News & Views | Ohm Speakers | Custom Audiophile Speakers for Music & Home Theater
There's more of course, but for now the most important ones for you + any personal reasons/preferences yet stated, so only you can decide which to choose.
Otherwise, my default recommendation is don't add any mass since it will make it too heavy relative to its effective motor strength, so would ideally need to be tuned below Fs, which at ~23 Hz is close enough to the THX 20 Hz reference in room.
Of course there's hundreds of movies with true infrabass [<20 Hz], so may want to add mass if/once 'we' know more about the room, any limitations such as neighbors, etc.: The Ultimate List of BASS in Movies w/ Frequency Charts | AVS Forum
That said, unless this brand is known to publish accurate enough specs, then most likely the motor will be weak enough to need to be tuned below Fs, so between the room, driver, unknowns, best to measure both with REW or similar: https://www.roomeqwizard.com/
GM
Thank you for granting me such a concise answer! The brand I mentioned is well known in Germany for producing astonishing good price/performance ratio subwoofers! A few examples are the
AW 3000 for 49€
AWM 124 for 79€
There are also many subwoofer kits/blueprints for these chassis, but I can't find a fitting one for the XAW 320 HC.
As for the room, it's dimensions are 3.8m x 4m = 15.2m² (12.5ft x 13.1ft = 10.76ft²). The subwoofer is most likely to be located in the left corner. Neighbors are non existent, so that eliminates a possible angry interference!
Could you explain me what REW is able to do? I have only heard of it but never really understood how it works and what it provides!
I have simulated an enclosure and I am not sure if a flat frequency response is preferable or a bump in the lows. I have attached an image of the response. (200l tuned to 25hz)
Thank you again!
AW 3000 for 49€
AWM 124 for 79€
There are also many subwoofer kits/blueprints for these chassis, but I can't find a fitting one for the XAW 320 HC.
As for the room, it's dimensions are 3.8m x 4m = 15.2m² (12.5ft x 13.1ft = 10.76ft²). The subwoofer is most likely to be located in the left corner. Neighbors are non existent, so that eliminates a possible angry interference!
Could you explain me what REW is able to do? I have only heard of it but never really understood how it works and what it provides!
I have simulated an enclosure and I am not sure if a flat frequency response is preferable or a bump in the lows. I have attached an image of the response. (200l tuned to 25hz)
Thank you again!
Attachments
You're welcome!
Good to know, thanks!
OK, will get back to cab design musings as time permits.
Basically everything a DIYer will likely ever need WRT measurements, rooms acoustics driver T/S specs and all associated measurements: REW - Room EQ Wizard Features and Screenshots
When placed near/at wall, floor, corner boundaries, speakers normally need to be tuned low/rolled off to offset the room's rising gain and can 'visualize' it using a water wave generating tank's splashing [up] against its walls, hence the sealed cab suggested.
GM