6BM8 triode connection non-feedback tube amplifier design production, circuit diagram, recording
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18:04
6BM8 pentode connection vacuum tube amplifier design production, circuit diagram, recording
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22:17
パクリドメイン風・8cm 卵型コンクリート自作スピーカー真空管アンプで聴いてみる
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46:21
The 5 kilowatt Crown
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16:59
Rare Old Engines Starting Up Sound That Will Blow Your Ears ▶3
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20:46
【電子工作】トランジスタ一つでオーディオアンプを作る!
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22:16
Water pump without electricity that can pump water up to the hills
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26:22
後悔先に立たず!真空管プリアンプに見る 悪徳・宮甚商店の手口
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28:54