Darling monoblocks

[Greyskale]

Hello all. I've been tinkering with the idea of doing a pair of Darling monoblocks. Cost of iron and parts for this amp make it a good candidate for mucking about with. Looking at the schematic, I'm under the impression I need to replace the cathode resistors with trimmers for Biasing. Although to be honest, as my first tube hifi project, I'm more or less taking a shot in the dark with that one. Can anyone suggest how to modify the circuit for monoblock design? Thanks in advance.

 

[billr]

hi as the bias resistors will have half the current, you need to double the value for monoblock working.

You can also do a hybrid thing, if the bias resistor is to be 1000 ohms, put in a 820 ohm resistor and a 200 ohm pot, you can then twiddle it to get the bias voltage that you want.

hope this helps

bill

 

[Greyskale]

Thanks Bill. I actually spoke with Bob on this, his suggestion was to avoid monoblock construction with this amp because the coupled cathodes have an audible benefit. I'd honestly prefer it for aesthetic reasons, but he is the creator of this amp, so I'm going to trust his judgment on this one 😉

 

[billr]

hi,

I've seen that circuit over the years, and all it's ever meant to me is lots of cross talk between the channels.

I don't know if that's a good thing or not, but nearly everyone else on the planet avoids that like the plague.

what the hell though, give it a blast and see if you like it or not. To be fair with two fairly small valves, they would be titchy monoblocks,

I would be interested to hear when you build this, if you try it with and without the coupled cathode resistors or not.

best of luck.

bill