I just woke up around noon. I found that it was fine when I opened the window. I decided to go to Hi-Fi Do and I went out taking a broken full range speaker immediately. I showed it to the manager as soon as I arrived at Hi-Fi Do. He said, " It looks ok as far as I look over on the surface. So, check the condition by connecting it to an amplifier." It did not sound even though it was connected. He said, "Why don't you buy another one because it only cost JPY100 per unit." It was so cheap that I decided to buy 3 units. I went the speaker shop and found 3 sets of speaker were available. I chose three units in good condition and paid JPY300. I connected them soon after I arrived at home. I found one of them could not sound at all. However, I had to put up with the broken speaker because it cost just JPY100.
I remembered that I saw the rare speaker at Hi-Fi-Do and I asked about it to the manager on the phone. He said , "It is CORAL BX-800." My negotiation made him offer reasonable price. So , I decided to buy it. I have not listened to the sound of BX-800 yet but I am auusred that it will produce excellent sound.