100W Ultimate Fidelity Amplifier

Questions for APEX A33

Hello, mr. Mile. I have a few questions about the APEX A33 amplifier (2 pairs of output transistors).

The maximum supply voltage is? (V)
Nominal supply voltage -? (V)
Power per load 8 Ω -? (W)
Power per load 4 Ω -? (W)
BIAS output stage -? (MA)
THD -? (%)

Thank you!
 
Hello, mr. Mile. I have a few questions about the APEX A33 amplifier (2 pairs of output transistors).

The maximum supply voltage is? (V)
Nominal supply voltage -? (V)
Power per load 8 Ω -? (W)
Power per load 4 Ω -? (W)
BIAS output stage -? (MA)
THD -? (%)

Thank you!

The maximum supply voltage +/-65V
Nominal supply voltage +/-55V
Power per load 8 Ω 120W
Power per load 4 Ω 200W
BIAS output stage 60mA
THD 0,002%
 
Hi sir Mile, you can help me about f100 psu ? I have a trafo with 2x48 AC and i want to modifi the psu for this trafo. What change need to make? ............
a dual 48Vac transformer is likley to give you ~+-70Vdc on your amplifier supply pins.
It will be higher when your mains supply voltage goes higher than the transformer rated primary voltage.

For a nominal +-55Vdc you should be using a dual 40Vac transformer, or a little bit lower (38, or 39Vac).
On my 240Vac mains I get ~ +-58.5Vdc from a 230:40Vac 4% regulation transformer.
 
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a dual 48Vac transformer is likley to give you ~+-70Vdc on your amplifier supply pins.
It will be higher when your mains supply voltage goes higher than the transformer rated primary voltage.

For a nominal +-55Vdc you should be using a dual 40Vac transformer, or a little bit lower (38, or 39Vac).
On my 240Vac mains I get ~ +-58.5Vdc from a 230:40Vac 4% regulation transformer.

Whit this trafo conected to f100 PSU AND 10.000UF JVC super audio capacitor 71v i got +- 65 VDC without f100 amp conected on the psu. At +-65v F100 amp give me 390w on 4R and 190w an 8R
that is really good. Sorry for my english. ALL THE BEST!
 
you have not measured correctly.
Try measuring the transformer when it is delivering it's rated power into the rated resistive load.

eg.
If you have a dual 48Vac 500VA transformer, then the rated current is 4.208Aac
The rated load will be 48Vac/5.208Aac = 9.216ohms
You need two power resistors rated for well in excess of 250W each with a value of 9r216, then you can measured the rated voltage when you input a mains voltage equal to the rated primary voltage.

Did you do any of that?
 
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Mr. Mile,
I have added rail decoupling near the o/p device and also ground lift.
Is it recommended?
+some reduced the PCB size to 68mmx75mm

reg
Prasi
PS; many revisions, but i want to make it as good as possible.

edit: the black jumper is optional jumper to reduce the trace length from C7 to C of T6.

a tribute to Mr. Mile.
 

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