Accuphase A75 Voltage conversion 100v-230v


Hello, I would like to request advice regarding changing the voltage of Accuphase A75 from its Japanese 100V model to 230V. While I have experience with voltage conversions, this is my first time working on an A75 model, so your assistance is greatly appreciated.

The basic modification plan involves rewiring the main transformer wires in parallel, replacing the fuse with an 8A slow-blow fuse, and changing the relay jumpers from J1 and J3 to J2. I intend to include circuit photos for reference. I have already measured the resistance allocation of the main transformer wires using an LCR meter.

https://drive.google.com/drive/folders/1jEZNpgb04ZSw6yBU3Tum0yNrq4RdXZ6P?usp=sharing

  1. Orange - 120V Red - 100V Grey - 0V

  2. Yellow - 120V Brown - 100V White - 0V

To achieve 230V, I believe I need to connect Orange to Grey and Yellow together in parallel, leaving White as it is. If you have any advice or suggestions, please share them. Thank you!!

 

yaman5055

I'm sorry! I made a mistake. 230V is connected in series.
I believe that the E280 and E380 amplifiers do not use the lower-model triad transformers, so it seems that relays and soft-start circuits may not be necessary.

YAMAN congratulation for you successfully changed the voltage of the A75!
@yaman5055 

is that only 2 step without any welding?

first step is
220V 1 = orange, 2 = red, 3 = grey+yellow, 4 = white, 5 = brown

second step is
change the fuse.

than 220v is done, enjoy the music




my friend say maybe the soft-start board should made some change, is this also correct in a75?

thank you so much, i might bought a75 or a70 too.

You will need to change the jumper on the soft start circuit. Change the J1,J3 jumper to J2. Do you have any gear? If you want to buy it, you can count on me selling it on eBay.