500W PA amplifier with Limiter

For me, the specifications of this amp like Frequency response,S/N ratio,Damping factor etc is not impotent, but what is impotent is this amplifier sound is so good. can be used for out door. like 4x 18'' speaker

Is there any wrong in knowing the characteristics of this?
It may not be important for you but for me or other diyers may have an important factor in knowing this,

some one said that bass is dry and other person said crisp is low and not good at high-frequencies about this amp in this forum by this how can we know that this amp will drive woofers,mid-range,full range,hf speakers?
 
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realization

thanks apex for this amp, here there is my realization. i've divided into two section for the final project and modified some components to work at 4 and 2 ohm since it'll drive a subwoofer, input 26vac dual and i've removed all protection. anti-bump, dc output etc will be implemented via microcontroller, also the active crossover. if anyone interested i can post pcb in pdf format, ready to print!

20120216_204958.jpg

20120222_214030.jpg
 
The pcb design was very good, but perhaps it would have been better to design the output stage with the copper side on the same side as component side.

Then it's much easier for measurements and exchanging parts, particularly the transistors.

As it is, to replace any part you have to disassemble the whole thing.

Sorry to speak that now, but just now did I see this thread.
 
Carlamart you're all right, but i'm new to pcb and i've never think about such kind of design. however if i design the board like you say i always have to mount transistor downside cause of heatsink size and any replacement service needs still to disassemble the whole board. thanks for suggestion, next board will be better :-D
 
pcb and schematic

pcb of my b500 clone is attached.

pay attention to feedback link from zobel filter and other circuitry (highlighted in red) cause isn't present on pcb since it is a piece of cable. (if the zobel is connected directly on speaker, this cable can be omitted so more professional design :))

pcb.jpg
 

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