Hi Clip,
Not to discourage you.
Building an Amp & building a car Amp is a totally different ballgame.
Would suggest you try building few small amps based on chips to gain knowledge and confidence and then move on to bigger project like a car amp.
As already indicated by LBM, most common chips can not hold more than 3Amps so theoretically you can not have more than 12v x 3A = 36W leave out few watts as losses, even with bridge mode they are not much efficient (read music to ears).
With regular 12V supply voltage
There are some popular Chips from ST & National (4440, 12xx) which you can try initially, but nothing from theses can pump bass in you car Sub. There are other options like Sanyo STK series, but require higher and symetrical power supply for operation.
A typical Car Amp consists of:
1. Power Supply
2. The main Power AMP
3. Preamp and active filter (usually)
For a DIYer the biggest challenge is to convert 12v DC to symmetrical power supply (+, 0, -) as per the AMP design. This Power supply should be able to deliver stable output voltage, regardless of the input voltage (usually the car electrical system will range in 9-15Vdc).
The DC-DC converter is usually a SMPS (Switch Mode Power Supply), few popular chips are TL494, SG3524, SG3525 etc. Generally SMPS used in car audio amplifier is the push-pull system with switching frequency between 20-70Khz. Also it needs to have some sort of protection to protect the AMP and your expensive Sub from overload, heat, and other abnormal conditions.
There are quite a few popular designs floating around for the main amp you can search on the web.
You can select a matching preamp and active filter design based on your Main Amp.
Not sure about Jalandhar, but you can get few good amp kits from Rajindra Electronics in Sec-35, Chandigarh. For spares and other components you can try Anand / Anil electronics in Sector 18, Sonia electronics in sector 42, above Gobind sweets.
Keep us posted...
Quote:
Originally Posted by
navin It used Hitachi 2SK135 and 2SJ50 MOSFETS (I hope I have these numbers right becuase my memory is not very good today).
I am big fan of Hitachi Mosfets, the popular design around this matching pair was Crescendo and Mini Crescendo, could not locate these for long time, last i checked on Lamington Road it was Rs750/- a pair, too steep.