Plate amp?

[molitovv]

Hi everyone,

This is my first ever thread, so please bare with me. I am looking at building a plate amp for a 400w 12 inch sub, for home theatre.

can anyone point me at some good plans or ideas, i dont mind converting a normal amp to a plate amp setting.

so you know, i am an electrician, competent with a soldering iorn and also have the access to any metal working machinery i might need.

i want a really high quality finished product and dont mind a major project to achieve that, any ideas?

thankyou so much in advance!

Matt

[molitovv]

You guys were super helpful,

throw me a bone!

[BobEllis]

Here's a bone -

Any amp design can be built on a plate. find a suitable design, and make the plate bigger than the heat sinks required. You'll want to cut out holes in the plate to mount the output devices directly to the heat sink, and probably build an enclosure over the side facing in.

Not to kill the DIY spirit, but plate amps for sub use can usually be purchased for significantly less than the cost of building something equivalent. If you can stand the rack space, you may be able to find a suitable used PA amp for even less.

Subwoofers are where you can get away with lower amp quality than the main speakers. "Better quality" subwoofer amps will show little sonic improvement for teh money invested, as long as the basic power requirement is met.

[quasi]

This module with 75 volt rails will deliver around over 400 watts RMS into 4 ohms. You should upgrade the FETs to IRFP360 or similar.

http://www.diyaudio.com/forums/showt...263#post600263

You will also need a parametric equaliser to tailor the response.

Cheers

[amplifierguru]

Hi Molitovv,

What's the impedance of your 12" sub? Is it to be a single channel (L&R combined)?

A sub can be easily overdriven such that a 200W amp can deliver 400W square waves to it if overdriven, very easy to do as the clipping distortion is not obvious in a limited bandwidth driver.

My GB300D fully complementary Patent pending 'modulated cascode' design could give you 300W rms (4 or 8ohm) and is virtually Rail 2 Rail making the most of the power supply. See -

300W 'modulated bias' cascode Killer Amp

Or check my website -

http://members.dodo.com.au/~gregball/guru_006.htm

For tailoring the response I suggest a tailored version of my 'Bass Extender', see -

New Bass Extender

and website -

http://members.dodo.com.au/~gregball/guru_010.htm


Cheers,
Greg

[molitovv]

thanks for your help guys, im hearing what you are all saying, thanks for the advice, im doing this both as a bit of a learning trip, as well as a project for projects sake.

i havent selected my driver yet, but id say it will probably be 8ohm

thanks guys, your awesome

matt