Wanted 36ohm 1/4 Watt 1% Metal Film Resistors

[Barry]

I've been doing some research and it seems no-one knows how Dada derive the values of R13 for reduced sensitivities. You probably won't go wrong with using a 27ohm value to achieve a sensitivity of 1V, but some have expressed concerns.

These being that increasing R13 increases negative feedback, which in turn increases the loop gain, and this results in a lower stability margin and a greater chance of ringing on transients.

The preferred method is to fit an attenuator between the Hafler pre and the Quad 306. A simple series resistor of 47Kohm will reduce the source voltage fed to the 306 to 1V. That is still around 2 and half times the base sensitivity of the 306, but will allow more of the range of the volume control to be used.

(Suggest you keep the 9.1Ohm resistors in case you are unhappy with Dada's suggested scheme, so you can restore things back to the status quo. If you don't want to mess around fitting 47Kohm resistors to either the input of the 306 or on the output of the DH101, then you can use a 10dB in-line RCA phono attenuator.)