Headphone Amplifier 7 Watts

[neonixcool]

Good day
Dear gents
In attachment my prototype of 7 watts headphone amplifier for 15 ohms load
For huge load isodynamic headphones

 

[neonixcool]

 

[martin clark]

That looks like fun!

Where are the power transistors - under the pcb / bolted to the base plate, near the front panel..?

 

[per-Sony-fied]

That looks like fun!

Where are the power transistors - under the pcb / bolted to the base plate, near the front panel..?

Take another look, you are close to right... between the headphone socket & Alps pot bolted to the base plate. And 1 in the corner, almost hidden by the headphone socket. I suspect there is 1 out of sight for the other channel by the Alps pot. That must be them.

 

[neonixcool]

That looks like fun!

Where are the power transistors - under the pcb / bolted to the base plate, near the front panel..?

Good day
The output transistors install under main board and screw to chassis on photo near volume reg and output 6.5 socket

 

[neonixcool]

The first version have a SMD output transistors Zetex FZT
But after listening with 20 ohms Snorry Trion headphones the output stage is very warm

Now time all output transistors have touch with chassis and not hot with 15 ohms loads.
Output stage have a quasy complementary schematic but not naim. This is next generation ideas of Baxandal technology with better linear class B output.
Headphone Amplifier have a 22 transistors
11 transistors per channel
Power transformer about 45VA have two windings 15-0-15v

 

[neonixcool]