sub woofer amp

[space2000]

hi,

i want to make a sub woofer amp incliding sub woofer box.

the woofer will be 12 or 15 inch dia, 4ohms.

what kind of amp should be drive this speaker (means wats)?

is there any circuit design for this type of sub amp?

thank you.

[AndrewT]

If the 4ohm speaker is 100dB/2.8V/m then 50W into 8r0 will drive it to 120dB @ 1m.
If your speaker is only 90dB/2.8V/m then 500W are required to drive it to 120dB @ 1m.
If you decide to add 16db of EQ to flatten the response, then your low sensitivity speaker will need 20kW to achieve that same 120dB @ 1m. or much more likely 1kW to achieve 107dB @ 1m.

Telling us it's size and it's impedance does not go anywhere near helping answer your question.

[Dan2]

your budget is also an important factor. generally you go for as much power as you are willing to pay for

[EWorkshop1708]

Originally posted by Dan2
your budget is also an important factor. generally you go for as much power as you are willing to pay for

I agree. Get as much amplifier power as you (and your sub) can handle!

However, if on a small budget, I'd recommend at most 150-200W RMS with a cheap 12 or 15 and it will sound great, and it's not enough power to blow the speaker in most cases. Car Subwoofer 12's can be bought for under $100 and they are 4 ohms and take that kind of power nicely.

[space2000]

is there any special amp circuit 150-200w for subwoofer?

[AndrewT]

The Leach Low Tim gets that power.
The Leach clone can get 170W into 8r0 from a 40+40Vac transformer.
Crucially does this safely on 63V smoothing caps, thus keeping costs lowish.