cheap DIY subwoofer

[bottedumal]

Hey guys!

I am now living in colombia and there are almost no choice of subs here, or very expensive.

And as it's heavy, it's also expensive to ship from US.

That's why I've been considering the DIY option.

I found this driver that seems to be great
GRS 12SW-4 12" Poly Cone Subwoofer 4 Ohm

Now, I don't know anythink about making subs.

Would this be sufficient to drive it ?
Dayton Audio SA70 70W Subwoofer Plate Amplifier

It will be connected to a SMSL AD18 sub out, along with my klipsch rb61 ii bookshelf speakers

About making the case I imagine i'll find some guides here, but what amp should I get ?

Is there any class D amp that would be fine for this that I can find cheap on aliexpress ?

The idea is to make it the best possible for under 100$ budget

thanks guys!

 

[bottedumal]

I found this amplifier

Lepai LP210PA 2x30W + 60W 2.1 Channel Mini Plate Amplifier TPA3118

I can get it for cheap here. Would that drive the GRS 12SW-4 ?

What can I expect if I build the box correctly ? Comparing to a BIC F12 for instance worse or better ?

 

[Brian Steele]

Why are you considering shipping from the US? Check Brazil - aren't Selenium drivers built there?

What you've outlined in your post might work, but if I was in your situation, I'd check to see what's available in Brazil before shipping in something from overseas....

 

[bottedumal]

I'm considering this driver now

Yung SD100 100W Class D Subwoofer Plate Amplifier Module No Boost

or

Yung SD100-6 100W Class D Subwoofer Plate Amplifier Module with 6 dB at 45 Hz

not sure to get the 6db boost one or not.

I like the yung over dayton for the fact they support 220V too (if I ever bring it to europe)
And it's a bit cheaper


Now my question is, how would this setup (plate amp 100w + GRS 12SW-4) would work, if I make the case well ? Can it be compared to a BIC F12 ? better ? Worse ? thanks!

Brian Steele, from what I've seen, the easiest way to get electronics to here is from the us ;-)

 

[bottedumal]

also, considering the speaker power ratings are:

Power Handling (RMS)120 Watts
Power Handling (max)240 Watts

@4 ohm

Am I ok with an amplifier 100w@4ohm ? Or better get the 300w@4ohm for 125usd ?

I think the 100w is safer, as the other can overpower the driver and burn it, am I right ?

 

[bottedumal]

Apparently I should get the 6dB boost one if I do a sealed box.
the no boost one if I do a ported box.

Now, I imagine the ported box is better, but is it much more complicated to make ?

 

[GM]

With a 3.18 ft^3 Vas and Qts = ~1.0 after adding a bit of wiring resistance, any ported box will have to be large and heavily stuffed for best overall performance based on published specs, but this brand isn't known for its accuracy.

Regardless, the recommended vented cab sims a ~9 dB peak in the 50s and a more realistic 160 L with ~6 dB peak and sealed peaks at 50 Hz, so a bass boost in the 40s seems a waste of $$ for either unless you heavily stuff them and/or like 'one note' bass.

GM

 

[bottedumal]

GM thanks but I'm not sure I understood that.

You said vented cab would be very large ? like how large ? where can I get appropriate plans for the box ?

 

[KaffiMann]

Like half a fridge kind of size. So not too big.

Have you tried checking local or Brazil availability of Selenium 15WS600? It looks to be an excellent unit, and might be a much better solution than doing lots of upgrades with cheap units sent with expensive shipping.
Selenium 15WS600 15" 600W Woofer

 

[GM]

GM thanks but I'm not sure I understood that.

You said vented cab would be very large ? like how large ? where can I get appropriate plans for the box ?

You're welcome!

Well, ideally it needs to be around 400 L/14 ft^3 net, but a damped to 'taste' 160 L/5.65 ft^3 net vented cab gets you all but the huge cab's deep bass an octave down [20-40 Hz].

The rest was just explaining why you most likely don't need an amp with a 6 dB boost at 45 Hz.

I don't do drawings, plus most folks have one or more space limitations, so do you have any and/or want a particular shape? Otherwise I'll just post dimensions for a golden or similar ratio rectangular box.

GM

 

[bottedumal]

Like half a fridge kind of size. So not too big.

Have you tried checking local or Brazil availability of Selenium 15WS600? It looks to be an excellent unit, and might be a much better solution than doing lots of upgrades with cheap units sent with expensive shipping.
Selenium 15WS600 15" 600W Woofer

there is this:

https://articulo.mercadolibre.com.c...te-15-pulgadas-800wliquidacion-_JM?quantity=1

and:

https://articulo.mercadolibre.com.c...jbl-gt5-15-de-alto-rendimiento-_JM?quantity=1

https://articulo.mercadolibre.com.co/MCO-467420958-selenium-12pw3-slf-controlador-de-12-pulgadas-_JM

https://articulo.mercadolibre.com.c...e-12-pulgadas-500w-liquidacion-_JM?quantity=1

https://articulo.mercadolibre.com.co/MCO-446602024-parlante-jbl-bajo-gt5-12d-_JM

https://articulo.mercadolibre.com.co/MCO-452864515-parlante-12-400w-pronext-_JM?quantity=1


but nothing seems as interesting as the GRS speaker for me.
honestly everytime it cost cheaper to get from USA, even with shipping, for this kind of things (electronics)

but if you see a very good one, tell me. as a reference 320.000 is 100usd

 

[bottedumal]

Like half a fridge kind of size. So not too big.

Have you tried checking local or Brazil availability of Selenium 15WS600? It looks to be an excellent unit, and might be a much better solution than doing lots of upgrades with cheap units sent with expensive shipping.
Selenium 15WS600 15" 600W Woofer

half a fridge with a 12" or 15" ? still a bit big, how big would be sealed ? I was reading sealed is actually not so bad

 

[bottedumal]

You're welcome!

Well, ideally it needs to be around 400 L/14 ft^3 net, but a damped to 'taste' 160 L/5.65 ft^3 net vented cab gets you all but the huge cab's deep bass an octave down [20-40 Hz].

The rest was just explaining why you most likely don't need an amp with a 6 dB boost at 45 Hz.

I don't do drawings, plus most folks have one or more space limitations, so do you have any and/or want a particular shape? Otherwise I'll just post dimensions for a golden or similar ratio rectangular box.

GM

OK. It's more clear now.
I'll get the no boost plate amp, and the GRS speaker in 12".

But but but... 100w amp is ok for this speaker right ?

It'll cost me like 120usd in parts + shipping, plus the wood, can I pretend to have the quality of a 200usd sub ? or better ?

THanks

and for the size, i consider two options: or making a small one, sealed, or making a big vented one, that could be use as a table or somethink like this to put stuff above it

 

[bottedumal]

also hesitating with the 15" grs speaker

but it's for watching movie and listening music in small room. not sure that is necessary

 

[KaffiMann]

I guess the Eminence Delta 15a in a closed box might be an acceptable solution, not a whole lot of travel on them.

The cheapest (299.900 for a pair of Pronext T-SW3803) 15" that might be "ok" on the site you posted is probably these
https://articulo.mercadolibre.com.c...1000w-pronext-2-unidaes-pareja-_JM?quantity=1

But I could not find the T/S parameters anywhere. There seems to be a thread on a Columbian forum they discuss them a little bit
Parlante para bajo Pronext Ts-w3803 o Spain 1565c ? | Foros de Electronica

If you can find a spec sheet with T/S parameters for those Pronext thingies it might be your best bet for excessive bass on a budget, and in stereo no less!

 

[johngalt47]

Have you tried asking the member named Destroyer X? He lives in Brasil.

 

[hollowboy]

Why are you considering shipping from the US? Check Brazil - aren't Selenium drivers built there?

PRV audio are also based in Brazil. Are they cheap for locals?

The 15W700 looks like a budget driver with decent specs for a big sealed box (about the size of a bar fridge) - good for a 1st time builder.

Apparently I should get the 6dB boost one if I do a sealed box.
the no boost one if I do a ported box.

If your source is a computer or good digital media player, you can add whatever equalisation you want. That's what I'd go for, rather than a built-in boost.

Now, I imagine the ported box is better, but is it much more complicated to make ?

Yes, a ported box is more complicated, particularly with low cost drivers that might not be correct to their specifications, and if you have no measuring gear to check what the real values are.

The idea is to make it the best possible for under 100$ budget

You'd probably need to get salvage / free timber to keep the price that low.

Another way to keep the budget down: use a bare amp board + a power supply salvaged from a laptop or similar, e.g. post 6 in this thread:

Very simple Yuan Jing build (noob questions)

 

[bottedumal]

hi guys

thanks a lot for these infos.

I decided still to go with the GRS 12 inch speakers as the feedbacks are excellent, and there are specs, even if not 100% good, still better than the low costs of here that don't have any datasheet. And also, it was still the cheapest option.

I also buy the Dayton Audio 100w plate amplifier.

I took this one over the yung 100w, because it's more famous, and I saw reviews that seems to show that it has more power.

I hope this will lead to something good.

So this order is a total of 100$, with like 20$ shipping to colombia.

Now I have to find some plans, I don't know anything about making a subwoofer, so if you guys have some vented sub plans that could serve this hardware I bought that would be awesome thanks!

 

[bottedumal]

parts express gives the following for this speaker:

Recommended vented enclosure: Vb = 2.5 ft^3, Fb = 32 Hz, F3 = 30 Hz

GRS 12SW-4 12" Poly Cone Subwoofer 4 Ohm

 

[bottedumal]

one of the advice says


TS params measure very close to spec
I bought several of these drivers and tested six of them to check the TS parameters. I did not break in the drivers before testing, but was very happily surprised when I found that all six were very close to the advertised specs. This is a testament to good quality control and manufacturing practices, and I will definitely be considering other GRS drivers in the future.