B1 with Korg Triode

Wayne Colburn designs the Pass Labs preamps. 😀 Has for the last 25yr or so...

The Muses 72320 is used as the volume control in all the current Pass Labs preamps, including the XS.

That’s a good enough endorsement for me to want to try it!! :yes:


🙂 🙂 🙂
 
I am very keen to try the Muses on my Build, I have listened to the Korg B1, with a variety of Volume Controls on board.
From Dual Toco's , a Single Pot, Stepped Att, and a Promethius AVC.
The Muses was to let the other owners of the KB1 have a listen to Muses.

I am even more Keen Now ! after being informed it has a inbuilt balance option.

My Investigations to date have been to produce a Dual Mono Volume Control using the Muses to offer the same experience as my Slagle AVC can offer to control the volume on each channel.
The inbuilt Balance Control should I hope be a decent alternative.
 
Put bib on some dissipation metal.

From Ultra-Bib guide:

Transformers
You should choose enough secondary voltage for the rectified DC across C1 (Vin) to reach 5V higher (or more) than your Vout setting. Rectified DC=(VAC*1.414)-1.4V diodes drop. Use 9VAC for 5- 7Vout, 12VAC for 8-10Vout, 15VAC for 11-15Vout, 18VAC for 16-19Vout and so on and so forth up to 33VAC max secondary not to burn a JFET. The reg works even with less than 5V difference because CCmA weakening starts only at Vin-Vout <1.7V for ~200 CCmA settings. At 600mA CC it starts weakening at Vin-Vout <2.5V. But more voltage space allows for mains play and for better M1's parasitic capacitance. For VA choose transformers with three times the power of your CCmA*ACV across all their utilized secondaries. A 50VA toroidal transfo for up to +/- 300mA CC should suffice.
 
Just adhered the 6L6 promoted Prismacolor Magic Rub eraser via double-sided tape onto Korg Nutube. Some magic was acheived, as there was an immediate elimation of microphonic ringing. A $3 pack is $4 at Staples. I could not find any other local store that carried them. I am wondering if making four chassis feet out of the remaining two erasers (cut each in half) would further help. May give it try. Thanks, 6L6!
 
Put bib on some dissipation metal.

From Ultra-Bib guide:

Transformers
You should choose enough secondary voltage for the rectified DC across C1 (Vin) to reach 5V higher (or more) than your Vout setting. Rectified DC=(VAC*1.414)-1.4V diodes drop. Use 9VAC for 5- 7Vout, 12VAC for 8-10Vout, 15VAC for 11-15Vout, 18VAC for 16-19Vout and so on and so forth up to 33VAC max secondary not to burn a JFET. The reg works even with less than 5V difference because CCmA weakening starts only at Vin-Vout <1.7V for ~200 CCmA settings. At 600mA CC it starts weakening at Vin-Vout <2.5V. But more voltage space allows for mains play and for better M1's parasitic capacitance. For VA choose transformers with three times the power of your CCmA*ACV across all their utilized secondaries. A 50VA toroidal transfo for up to +/- 300mA CC should suffice.

Thanks - newb alert so please bear with me if you can.

So, if the transformer secondary VAC is 25V, then rectified DC across C1 = (25*1.414)-1.4 = 33.95V which is greater than 24+5 = 29V so a good choice Voltage-wise.
My understanding is that the B1K circuit draws less than 100mA CC, so a 50VA transformer should be ample.
 
My understanding is that the B1K circuit draws less than 100mA CC, so a 50VA transformer should be ample.

Go for it 🙂
 

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MeanWell interference

Hey there, I am having mixed results with the Meanwell PSU, it seems to randomly start oscillating and radiating really nasty RF, which gets picked up by various other components in the chain. I have a krell preamp, which is particularly susceptible. anyone else having problems with those little Meanwell powersupplies?