| Tube amplifier | 
| Pre amplifier-1 | 
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| It is a pre amplifier that Imade around 1970. It's the equipped is with frequency filter, round-ness, the tone defeat. Circuit diagram | ||
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| 1.Front panel is made very nicely. | 2.Rear side. | |
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| 3.Tube are using 12AX7A and 12AU7A. | 4.Wiring. | |