Install a 250 Ω, 1/8 watt, 1% Metal Film resistor between the 1/4" TIP and SLEEVE.

Install a 750Ω,1/8 watt, 1% Metal Film resistor in SERIES with the +4 signal, to the tip.

The two resistors will form 1kΩ load, voltage divider with 12 dB of attenuation.


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750 Ω |
\
/ 250 Ω
+4 dB In \ -10 dB Out
/
\
|
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