Hard to make choices with DIY subwoofer

[sreten]

Originally Posted by diystuff

See, the amp power is 300w rms and probably 600w peak. However, the driver's power handling is 400w rms and 700w max. So what value should I use in Unibox? 300w, 600w, 400w? So you guys are saying that the driver will only unload if the volume is on max? Also, on unibox it gives me three different port lengths and diameters, and like 2 different subwoofer box volumes. Which one should i follow? Standard design or Design by Vb, Fb and Q?

Hi,

Use the amplifiers RMS power. The Dayton 12" RS 4
ohm models best to me in around 4 cuft tuned to 20Hz.

rgds, sreten.

[mdocod]

For a 5-6ft^3 box size, You might also consider the DCS450. It'll produce a more natural "rolled-off" response that should balance well with room gain while providing higher maximum SPL capability through most of the musical bass range. It's $25 cheaper and weighs even a touch less (won't cost any more to ship) than the RSS315HF. I would suggest vented, tuned in the 19-24hz range.

[pinkmouse]

Originally Posted by diystuff

Thanks for the recommendation! But, European amplifiers are waaay too expensive compared to what I can get from the states. I'm on a budget of about 500 dollars for the driver and the amplifier. The less, the better

Don't overlook the hidden costs, as well as shipping, you will have to pay import tax and a handling charge from the courier, and this can be very expensive. You also need to make sure any amp you buy works on European voltage, not just US.

[diystuff]

Yep, I checked all the hidden costs and the price of the oaudio bash 300w amp should be far below the european amp prices. And Oaudio amps work here in europe too

On unibox, I chose the option 'minimal fill' as opposed to 'no fill' , 'heavy fill' and 'walls covered' for dampening. How much is minimal fill? How many lbs/kgs per cuft^3/liter? And is minimal fill good enough?

**Also**, I have decided to go with 3 4inch flared ports. Because, according to unibox, this will keep the air speed of the port under 17 m/s. Unfortunately each port has to be 44.5 inches long or 133 cm

I'm sure I can use some elbow joints and so on. I don't plan to buy pre-made ports but I will probably buy lots of abs pipe and precision port 4" flared ends and fashion three preposterously long ports.

I guess my sub will look more or less something like this (probably much worse on the finish) PB13-ULTRA - SVS

[diystuff]

And guys I know that the Oaudio 500w bash amp has a variable subsonic filter. THe 300w version doesn't have a variable filter but does it have a subsonic filter that is built into the amp itself? I know the non Oaudio version has a filter set at 18hz. Because if it doesn't have this subsonic filter then below 18 hz the sub is going to start to bottom out badly.

[mdocod]

Comparison of the DCS450 18" sub, to the RSS315HF 12" sub, each in 5.5ft^3 tuned to 18hz modeled at 250W amplification (Xmax limited on both drivers at about that same level).

It's all trade-offs but I personally like the way the 18" models out a lot better.

[diystuff]

Originally Posted by mdocod

Comparison of the DCS450 18" sub, to the RSS315HF 12" sub, each in 5.5ft^3 tuned to 18hz modeled at 250W amplification (Xmax limited on both drivers at about that same level).

It's all trade-offs but I personally like the way the 18" models out a lot better.

Hey...first of all thanks for taking your time and making graphs for me

I've tried using winISD but when i enter the parameters for the Dayton RSS315HF 12" sub, winISD calculates a ridiculous Fs of something like 200hz


Anyways, here are my unibox graphs...I would prefer to sticking with the 12 inch

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What do you guys think?

[sreten]

Originally Posted by mdocod

It's all trade-offs but I personally like the way the 18" models out a lot better.

Hi,

So do I by the looks of it, more room friendly. What does max SPL look like for both ?

rgds, sreten.

[diystuff]

Change of plans again...I can't make my mind up

Instead of the three, front-facing 4" ports. I will have two, front facing 4"ports, this is because I wont have enough room to accommodate those ports on my front panel.

I just read an article that elbow joints for the ports can increase chuffing. However, my port needs to be like 80 cm long...is it ok to use elbow joints (do elbow joints even exist for abs piping? can i use the dayton audio elbow joints?)

[diystuff]

BTW Here are the new and updated graphs with the dual 4" ports instead of the triple 4" portsPicture 1.png

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