[ihavet0es]

The 220uf 450v electrolytic snap-ins have non inductive leads so switched out the the CD micas with charcrofts. I also pulled the reservoir cap and added a 20uf film in parallel.
10uf electrolytics were also pulled and switched with films. The kemets I originally wanted to use didn't fit but able to stuff in the standard z-caps. Paralleled w/.1uf Dayton/Bennic film. Things sounded thin, less pronounced but detailed bass, more atmospheric. I didn't really like the sound so I added a CD942c cap .1uf. This brought mids forward and brought life back to the low end. Not more bass but everything has more attack with no loss of atmosphere.
Freya+ is so fun to work on and sounds excellent! Now it's time to mess with the tubes!

 

[prima186]

My favorite combination
"6AU6" triode connection（use "6AK5 tube converter adapter"）.
NEC 50's 6AU6

Vacuum tube data comparison.
6SN7GTB
Heater current 0.6A
Plate voltage 250V
μ20
Ip9.0mA (bias voltage -8V)
gm=2.6m

6N1P
Heater current 0.6A
Plate voltage 250V
μ35
Ip7.5mA (bias voltage -8V)
gm=4.35m

6AU6A (triode connection)
Heater current 0.3A×2
Plate voltage 250V
μ36
Ip12.2mA (bias voltage -4V)
gm=4.8m

 

[jlemaster1957]

My favorite combination
"6AU6" triode connection（use "6AK5 tube converter adapter"）.
NEC 50's 6AU6

Vacuum tube data comparison.
6SN7GTB
Heater current 0.6A
Plate voltage 250V
μ20
Ip9.0mA (bias voltage -8V)
gm=2.6m

6N1P
Heater current 0.6A
Plate voltage 250V
μ35
Ip7.5mA (bias voltage -8V)
gm=4.35m

6AU6A (triode connection)
Heater current 0.3A×2
Plate voltage 250V
μ36
Ip12.2mA (bias voltage -4V)
gm=4.8m

Super interesting. Sonic’s cap to 6SN7GTB? Vendor source?

 

[prima186]

Super interesting. Sonic’s cap to 6SN7GTB? Vendor source?

"6AK5 tube converter adapter"
https://www.ebay.com/itm/201606491849

You will also need an "8pin to 8pin" adapter to use it with Freya.
Excellent noise performance and easy to use.
"sylvania" "RCA" "GE"
I think you will get good results if you choose from brands such as.

 

[prima186]

"6AK5 tube converter adapter"
https://www.ebay.com/itm/201606491849

You will also need an "8pin to 8pin" adapter to use it with Freya.
Excellent noise performance and easy to use.
"sylvania" "RCA" "GE"
I think you will get good results if you choose from brands such as.

Self reply,

The machine I own is "Freya+", but I expect that "Noval" will give better results.
For "Noval", a US8pin to MT9pin adapter is required in addition to the 2in1 adapter.
US8pin to MT9pin adapter is available for purchase on ebay.
1PC DIY Adapter Socket Converter 6SN7 TO ECC83 12AX7 6.3V for Vacuum tube AMP
https://www.ebay.com/itm/304111049728?