[AudioCats]

the parts kit arrived, transit time was a little over 2 weeks, not bad. Parts look good, actually better than in the photos. LT1083 is used, other parts are new.

 

[GarageBoy]

I'm curious how different the circuit is from a bottlehead crack and darkvoice

 

[AudioCats]

the amp portion is basically the same as the darkVoice 336se. They use different input tubes (this one uses 6DJ8, while DV336se uses 6sn7), so:
-- input tube plate resistor is 47k (the two large 3w resistors); in the DV336 it is 30k.
-- input tube cathode resistor is 820 ohms (in DV336 it is 1k)

Output stage is the same though the idle current is much lower in this one, the output tube cathode resistors are 2.8k (two 5.6k in parallel), so maybe 30~40mA? While DV336 use 1k/20w (~70mA idle).

HV:
Marking on the PCB shows "130~160v AC". If using a 150v, the voltage before the capacitance multiplier will probably be around 210v and maybe 200v after the capacitance multiplier?
The DV336 doesn't use a capacitance multiplier, it uses the RC filtering with large reservoir caps. If I remembered right the HV rail in the DV336 is around 170v.

filament supply:
DV336 use AC for filament (hence the extremely annoying hum)
This one uses DC filament supply and it is even linearly regulated, a major overkill. This one should not have any hum. I guess the board was designed before switching type converters become common, hence the use of huge LT1083/1084 chips. Nowadays it is better to use a switching power module which generates much less heat (depending on the input voltage) and is pretty inexpensive.

 

[AudioCats]

From what I can see, the additional parts needed to complete this amp, to a somewhat "good-enough-sounding" state, will be:
-- 150v/100w power transformer, ~$55
-- film capacitors for output, $50~$100 (the cheapest route will be using ASC polyprop caps, 60uf per channel, then bypass with nicer caps such as Auri XO)
-- large enough power resistors for output tube cathode, and a way to mount these resistors OUTSIDE of the enclosure. (I will not use the 5.6k in the kit and absolutely will not mount them inside the enclosure). 50w resistor with aluminum housing. ~$15
-- DC/DC modules for filament supply, probably three LM2596 modules in parallel, each set to 6.8v with 0.47ohm ballast resistors at the output. ~$10
-- volume control with knob, RCA connectors, power switches, and other hardware ~$30

then a large enough box to contain everything.

The total project cost will be ~$200 and I am certain it will sound better than the stock DV336, and without any of the DV problems (major hum, un-usable volume control etc).

But I already have two DV336's, both with the DV problems solved and maxxed out. This circuit is similar enough to the DV, I won't learn anything from the project. I will not build this one.