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Old 22nd May 2014, 11:49 AM   #1921
stajo is offline stajo  Sweden
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I would say it probably needs some counting, testing and tuning. White CF is hard to make sound good imho.
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Old 22nd May 2014, 02:17 PM   #1922
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Thanks for the info.
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Old 2nd October 2014, 09:14 AM   #1923
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I measured the capacitance of the phono cable between the Itch & the #26 and measures 500pF (3 meters long), have I to increase the C of the Zobel step-up Jensen to 200pF?

Attached pic just for fun of increased mass of Linn Ekos tonearm, now Itch + Denon DL103R plays in other league.
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Old 2nd October 2014, 10:08 AM   #1924
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Oooops my mistake have I to reduce to 100pF?
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Old 2nd October 2014, 12:11 PM   #1925
Salas is offline Salas  Greece
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The SUT secondary termination (Zobel) is a different matter regarding the output of the full circuit. That Jensen could be fairly well compensated for square waves with 100-150pF in the Zobel too, at least on the oscilloscope tests I have shown before on my samples. You could try those values too for subjective impact.

The Itch output comes from a low impedance point (from the cathode follower part of the Mu circuit) and it can drive some cable capacitance. Its a 6mA 800 Ohm source with the 6SN7 in the V1.2.
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Old 2nd October 2014, 12:29 PM   #1926
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"The Itch output comes from a low impedance point (from the cathode follower part of the Mu circuit) and it can drive some cable capacitance. Its a 6mA 800 Ohm source with the 6SN7 in the V1.2."

Could you post a pic?
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Old 2nd October 2014, 12:41 PM   #1927
Salas is offline Salas  Greece
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Nothing different. As the output stage values in the V1.2 Valve Itch phono
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Old 2nd October 2014, 01:41 PM   #1928
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So I only have to change: R9-11 now 330R and R10 now 12K 2W?
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Old 2nd October 2014, 01:54 PM   #1929
Salas is offline Salas  Greece
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Yes, only the resistor values. The circuit topology is the same from the start.
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Old 2nd October 2014, 02:04 PM   #1930
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I have Kiwame 330R but I don't have 12K 2W
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