TU-8200DX - guidelines for exchanging the capacitors for better sound quality.

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8Ω loaded
UL 8W + 8W (6L6GC)
Pentode 8.2W + 8.2W (6L6GC)
Triode 4W + 4W (6L6GC)

The circuit around the jumper plug has high voltage and it is dangerous to touch the PCB without caution. Make sure to turn OFF the power and unplug the AC power cord, then wait for at least 10 minutes before changing the jumper connection.

Also, changing the connection while the power is ON could damage the tubes and the output transformers. Therefore please refrain from modifying the amp, such as adding a switch to change the connection.


Triode configuration



Here are some guidelines for exchanging the capacitors for better sound quality.

1. Exchanging the cathode bypass capacitors with conductive polymer aluminum solid electrolytic capacitors with low ESR
is very effective. In this amp, the 4 capacitors of C1, C2, C5, and C6 are used as cathode bypass capacitors. By default
they are 220μF 16V aluminum electrolytic capacitors. If you exchange, make sure the value is between 150 to 220μF, and the rated voltage is 10V.

2. Coupling capacitors affect the sound as well. In this amp, the PCB is designed with some extra
space around C3, C4, C9, and C10 so that users can exchange those coupling capacitors with different ones. However, those originally included are polypropylene non-inductive film capacitors that can cover high frequencies. Therefore you may not hear the effect even after they are exchanged.
If replacing these capacitors- the value should be higher than 0.1μF, and the rated voltage should be minimum of 400V. Please
make sure to select one which can fit in the provided space on the PCB without interference with other parts.

DX Model includes
• 4 X Amtrans AMCO 104 Metalized PET film capacitors (GOLD plated OFC leads)C3, C4, C9, and C10
• 4 X Nichikon conductive polymer aluminum electrolytic capacitors C1, C2, C5, and C6

 
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