The CS800S is an amplifier made by PEAVEY in the 90’s . Which is able of produce up to 800 Watts of audio power at 4 Ohm loads and 1200 Watts at 2 Ohm loads by 75VDC symmetrical supply.
INFO
The important thing you need to know is that the CS800 came out in the late 70’s with a height of 4u.
Then in the 80’s PEAVEY made the CS800X and in the 90’s made an amp with the name CS800S but comes in a height only 2u.
Why is the CS800S thinner than earlier amps but delivers the same power output?
The answer is because the amplifier uses Switching Power Supply Technology to produce a symmetrical 75VDC voltage with a current of bigger than 10 Ampere.
Meanwhile, the Elco they use for DC Output Filters is only 4 units of 1000uF/100V.
Elco DC filter resulting from the rectification of the diode which is a direct Line Power is only 2 pieces 2200uF/250V.
This means that it is very simple and concise even though there is a risk of additional SMPS circuits.
The appearance of the CS800S is as follows:
SCHEMATIC
The service manual contains 28 pages containing supporting documents of this amplifier such as a material list, schematic and PCB layout.
However, I only used the power amplifier scheme, and removed some of the difficult features of this scheme instead.
Firsly, the preamp uses a differential amplifier system involving Q114 and Q115.
While Q116 and Q117 are bias current stabilizers for preamps.
Q118, Q119, and Q121 are current mirrors for this amplifier to support the Q120 which acts as a voltage amplifier.
This circuit does not have feature a servo driver like other amplifiers.
But he has a DDT feature which I didn’t include in this circuit because it’s complicated.
This power amp has an Over Curent Protection feature by involving transistors Q122 and Q123.
The power driver uses 2 transistor levels starting from Q124 and Q126 and Q125 and Q127.
Finally, the power amplifier uses 4 pairs of power amplifier transistors with numbers 83180A and 73180A.
NOTE
Transistor number 83180A is equivalent MJ15024.
Transistor number 73180A has the same as transistor MJ15025.
Output power up to 250 Watt ( SOURCE ) .
With 4 pairs of transistors, its can be the power amplifier is capable of producing an output power until 1000 Watts in theory.
Moreover, if we calculate based on the supply voltage, The amp will be able to produce an up to 506 W at 4 Ohm load per channel or 800 Watt at 2 Ohm load.
