Power Amp

Hello attached is a power amp comments are welcome or if you see anything wrong please do tell me. Basucally this is one side. I am planning to bridge two of these to power a subwoofer this is why the load is 4Ohm. The reason for the TIP 2955/3055 is that Toshiba outputs sold here are counterfeited. Motorola and Mospec (MJ150xx) series are available but are more costlier than the TIP series. By the way BC546 has been used for simulation only the real one will have 2N5551 instead. Thanks for the comments you will provide


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It might not hit the full 84Vce but it will hit 80 to 90% of that at peak outputs that approach clipping.
The SOAR will be severely reduced at those voltages and the reactance of the load will probably take the devices well outside their temperature de-rated SOAR. The TIPs generally have little info on transient SOA ability, If you can't design it to be reliable then trial and error works if you have the resources to rebuild/improve it each time it fails.


2001-02-04 4:23 am
Q12 will work better with a 470R base resistor.

Look At the TIP35C/36C if you must use plastic.

Two pair of MJ15015/16 per half of the bridge would cost less and have 1.44KW SOA at 60V (about $20 for 8 pieces). This is the device Crown used in their Macrotech 600s (a bridge amp run on ±42V). The Crown uses two isolated (from chassis) heatsinks per channel, one at B+ potential, the other at B- potential. The devices are mounted with no insulators. Crown uses a TO-92 predriver, making the output stage a triple.
Attached is updated schematics with better SOA devices.
Something else i forgot to mention. The woofer to be driven is an 8Ohm 150W max a pair of bridged amp with +-42V PSU is too much.

Another solution would be to use +-42V psu + 2 woofers + 1 amp per woofer. The amp will be driven by an LR4 Xover and a linkwitz transform. What do you think of this one? Could also diminish output devices to 4 instead of 8

P.S: I already have 2 of these woofers


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