Just placed my Digi-Key order for the power supplies, LT4320/MosFET rectification and 47000uF > 0R2 > 47000uF times four. I should be able to start assembling the PCBs soon, once the metalwork is sent off to be tarted up.
I'm still mulling over adding a volume control. I was going to use a spare Muses module but it seems to be dead so I may put together a shunt switched attenuator.
I'm still mulling over adding a volume control. I was going to use a spare Muses module but it seems to be dead so I may put together a shunt switched attenuator.
do not - volume
even if Rin of SissySIT is highish, so not burdening preceding stage at all (and you can up input shunt resistor up to 330K without engaging brain at all) , you'll clearly hear anything detrimental in signal chain in front of Sissy
it deserves best you can give it, and passive connected attenuator in front of it - simply isn't that
why removing it from box later, and dealing with hole patching
even Muse, if not buffered properly, is Kiddie thing
even if Rin of SissySIT is highish, so not burdening preceding stage at all (and you can up input shunt resistor up to 330K without engaging brain at all) , you'll clearly hear anything detrimental in signal chain in front of Sissy
it deserves best you can give it, and passive connected attenuator in front of it - simply isn't that
why removing it from box later, and dealing with hole patching
even Muse, if not buffered properly, is Kiddie thing
OK ZM, not having a volume control makes the build simpler but what is your thinking for "it deserves best you can give it"?
The conventional options I'll have to hand will be a 2P29L tube preamp (about 20dB gain) or a buffered passive preamp (vintage BUF-03 buffer) - both have Muses volume controls.
Alternatively...
I only use a digital source, DSD based with HQ Player, which has a properly implemented software volume control. I have DSC2 and ValveDAC decoders (both of which have Lundahl LL1684 transformers on their outputs) though their output levels are lower than most digital sources at around 0.6V RMS (IIRC).
The conventional options I'll have to hand will be a 2P29L tube preamp (about 20dB gain) or a buffered passive preamp (vintage BUF-03 buffer) - both have Muses volume controls.
Alternatively...
I only use a digital source, DSD based with HQ Player, which has a properly implemented software volume control. I have DSC2 and ValveDAC decoders (both of which have Lundahl LL1684 transformers on their outputs) though their output levels are lower than most digital sources at around 0.6V RMS (IIRC).
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Some more porn for your edification...
To answer the question about the PS arrangements, here are some pictures withthe toroid temporarily in place. The 'Cap Bank' PCBs will be mounted on the opposite side of the channel section, you can see some of the holes for the stand-off bolts and the wiring feed through.
To answer the question about the PS arrangements, here are some pictures withthe toroid temporarily in place. The 'Cap Bank' PCBs will be mounted on the opposite side of the channel section, you can see some of the holes for the stand-off bolts and the wiring feed through.
DC supply noise spec
I am looking at my power supply and testing out a few options. First up is a cheapo SMPS driving a DIYAUDIO CRC board with 88mF per rail.
I am seeing around 10mV of 50Hz noise bleeding through from the SMPS. What is the supply noise spec for the SissySIT? Should I keep looking to reduce/ change to iron or is this low enough?
Top trace is output from CRC filter, 5mV/div.
I am looking at my power supply and testing out a few options. First up is a cheapo SMPS driving a DIYAUDIO CRC board with 88mF per rail.
I am seeing around 10mV of 50Hz noise bleeding through from the SMPS. What is the supply noise spec for the SissySIT? Should I keep looking to reduce/ change to iron or is this low enough?
Top trace is output from CRC filter, 5mV/div.
Attachments
Wanted to poke my head in here 
and mention that my current configuration is sounding REALLY nice. Sissy seems to have enough guilty pleasure on it's own, so I wanted to try something really clean in front of it. Wayne's LS has just the right amount of gain in stock form, super low distortion, and direct coupled..... I'm thinking of rebuilding it and going full dual mono with Jung/Didden regs to see if it can be taken even further (maybe even going with completely separate power company substations... well maybe not...)
and mention that my current configuration is sounding REALLY nice. Sissy seems to have enough guilty pleasure on it's own, so I wanted to try something really clean in front of it. Wayne's LS has just the right amount of gain in stock form, super low distortion, and direct coupled..... I'm thinking of rebuilding it and going full dual mono with Jung/Didden regs to see if it can be taken even further (maybe even going with completely separate power company substations... well maybe not...)