B1 with Korg Triode

Sure. The tube itself only needs about 12V, but you have to allow more for
the plate resistor bias and output swing. The character of the tube depends
on the current, plate voltage and load. Change one and you get to adjust
the others.
Thank you Nelson for your kind reply. So can I definitely go with about 21.8V? I ask this because I have a regulated PSU which gives me no more than that and I was wondering if I could keep it or change to something else...
 
All IMHO...

Papa is telling you that from a pure technical POV there is no prob running lower PS voltages, but that doing so you are likely to alter the sonic signature Papa took care to give to that little jewel - and that is quite the key of such a unit IMHO.

Of course, changing various bits you could probably find another or close sonic signature that fits your taste, but that requires R&D and some experience...

Short anwser: it is unlikely to sound EXACTLY as intented with a lower voltage. You can live with the doubt, as of me I wouldn't for the sake of a few Euros, not mentioning your SMPS has also to be a good quality one etc.

I hope this heps

Claude
 
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Hello Everyone,

I just built one of the kits for a friend of mine, and I combed through this thread somewhat carefully to see what everyone was doing for upgrades and tunes to this piece. I ended up going with the following (thus far):

KLE innovations RCA connectors
Takman REX Resistors in critical locations
Mills MRA-5 Resistors in power circuit
Vibration isolating rubber standoffs
Mundorf Supreme coupling caps (0.33uF, 1.0uF, 4.7uF) Precision matched
Nichicon UKT 2200uF 35V Electrolytics
Mogami shielded signal wire, PTFE/silver plated wire in signal path.

It was definitely a tight fit in the stock kit chassis. The coupling caps are double sided taped into the case so they don't move around, and it definitely required a bit of creativity to get the nichicons to all fit (definitely an oversight that they wouldn't clear the case top!)

The results are.. WOW. This thing competes with some really good stuff. Its clean without being solid-state-sterile. Excellent bass control, superlative mods, and realistic on the top end. Thank you to the community here for keeping such great tabs on the process, development, and mods for this little beast! Might have to go build myself one next!

IMG_4018.jpg
 
No can do. Hot water tank is powerline eth, and very chatty.

Trying to get an understanding of what's causing this; signal route ATM is DAC>pre>active speakers, when I bypass the pre and go DAC>actives... not a peep. Dead quiet. Very odd. Any ideas?
Have you tried a different power supply brick? It seems like noise in coming through the lines and the stock power supply is allowing the high frequency noise to come through.

For testing.... remember that homes have two sides of the 220 coming in... the "neutral" being the shared line. Try plugging the Korg's power supply into the other leg of the 220 ( get a long, three prong, heavy duty extension cord ). I figure your water tank, gateway are on different circuits but both are on the same leg, and your Korg is too. See if powering the Korg from the other side "solves" the problem.

Fundamentally, IMHO it's not a good idea to use networking over the AC lines... but it is what it is... so what you need is to add some filtering to the Korg's power brick AC line, or get a different one brick.
 

rmpfyf

Member
2015-12-27 6:28 am
Have you tried a different power supply brick? It seems like noise in coming through the lines and the stock power supply is allowing the high frequency noise to come through.

For testing.... remember that homes have two sides of the 220 coming in... the "neutral" being the shared line. Try plugging the Korg's power supply into the other leg of the 220 ( get a long, three prong, heavy duty extension cord ). I figure your water tank, gateway are on different circuits but both are on the same leg, and your Korg is too. See if powering the Korg from the other side "solves" the problem.

Fundamentally, IMHO it's not a good idea to use networking over the AC lines... but it is what it is... so what you need is to add some filtering to the Korg's power brick AC line, or get a different one brick.

Thanks. I'm in Australia where mains is LNE. The house has multiple incoming phases though the gateway communicates on the lot of them. I was a le to achieve a better outcome with better wiring etc. Not all noise is gone - it's within range of my tv (plasma - throws off some significant noise!!)

Tried multiple bricks, same result. Getting noise abatement right is part of why we DIY with much nuance to learn, and honestly the diyaudio community always seems to ship good parts.

I'm on the wait list for those filters though honestly I'm likely to recase the kit alongside a sigma11 PSU for fun, and switch the volume to a shunt type.
 

rmpfyf

Member
2015-12-27 6:28 am
Hello Everyone,

I just built one of the kits for a friend of mine, and I combed through this thread somewhat carefully to see what everyone was doing for upgrades and tunes to this piece. I ended up going with the following (thus far):

KLE innovations RCA connectors
Takman REX Resistors in critical locations
Mills MRA-5 Resistors in power circuit
Vibration isolating rubber standoffs
Mundorf Supreme coupling caps (0.33uF, 1.0uF, 4.7uF) Precision matched
Nichicon UKT 2200uF 35V Electrolytics
Mogami shielded signal wire, PTFE/silver plated wire in signal path.

It was definitely a tight fit in the stock kit chassis. The coupling caps are double sided taped into the case so they don't move around, and it definitely required a bit of creativity to get the nichicons to all fit (definitely an oversight that they wouldn't clear the case top!)

The results are.. WOW. This thing competes with some really good stuff. Its clean without being solid-state-sterile. Excellent bass control, superlative mods, and realistic on the top end. Thank you to the community here for keeping such great tabs on the process, development, and mods for this little beast! Might have to go build myself one next!

View attachment 1018070
Nice!!

Of interest... same pot?
 

rmpfyf

Member
2015-12-27 6:28 am
Yes, for now. If we go further with it then volume is the next step.. maybe something with a remote function. At that point it would need a larger case; I am thinking getting a deeper modushop case so the front and back milled panels could be retained.
I'm going to put mine in a more general 2U case, compartmentalise a better PSU and move to a stepped shunt attenuator.
 
I've been wading through the 7K plus posts while I wait patiently (?) for my back ordered kit. I have PMs NuTube vibration mount, rubber board mounts and a second Alps 50K pot waiting for their time to shine. My plan is to build it with dual-mono volume controls and therefore I am designing a front panel from FPE. I could use some help on the center-to-center measurements and diameter of the mounting holes of the DIYAUDIO Store's supplied kit's case front panel.
TIA, Karl
 
I've been wading through the 7K plus posts while I wait patiently (?) for my back ordered kit. I have PMs NuTube vibration mount, rubber board mounts and a second Alps 50K pot waiting for their time to shine. My plan is to build it with dual-mono volume controls and therefore I am designing a front panel from FPE. I could use some help on the center-to-center measurements and diameter of the mounting holes of the DIYAUDIO Store's supplied kit's case front panel.
TIA, Karl
Hi Karl, I‘m fairly sure that the case used by the DIY audio store is a custom version of the Galaxy 247 by Modushop/HiFi2000 with a 10mm front panel. If you are designing the case in CAD you should be able to download the DWGs of the plain front panels directly from the Modushop website (or at least that’s what I used to design a custom front panel for my B1k)