RE-ENGINEERED OLD AMPLIFIERS :-

MODIFIED QUAD 22 PREAMPLIFIERS.
Images, schematics and notes for mods to Quad22 preamps.

MODIFIED QUAD II POWER AMPLIFIERS.
Images, schematics and notes for mods to old Quad II
power amps to get better performance, the original Quad II amp schematic, and a graphs of THD.

MODIFIED LEAK AMPLIFIERS.
Images, schematics and notes for mods to TL12 Leak Point One
mono bloc power amps, and active protection, and graphs for frequency response and power output vs load.

MODIFIED DYNACO ST70.
Schematic and notes for revised integrated amp channel with power supply for 2 channels, and including basic active protection.

REFORMED JBL AMP FROM 1959.
Fig 6. Schematic for one 40W amp channel with all bjts and psu as replacement of germanium  transistors.
Explanations of schematic.
Fig 7,8,9,10, pictures of JBL amplifier after reformations and singing lessons.

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