B1 with Korg Triode

[spades]

Please send mine at your convenience have nutube bought as soon as heard about the b1 korg unit .Regards spades

 

[cjfrbw]

I bought a Nutube from the DIY store here in anticipation of the commercially available board, hopefully with JFETs and resistors. I have caps, diodes, chassis, power supply (on way) so I am ready to screw the pooch on the project.

 

[delecoy]

One more almost done

I'm too tired to finish it tonight, but one more will be running tomorrow. Cant wait to hear it with the vfet amp.

Thank you once more Mr. Pass!

 

[dewdrop]

Excited to hear what your impression tomorrow.

 

[DQ828]

Maybe I've missed this somewhere along the line but I was hoping someone could tell me what the input (without the pot) and output impedance is. I was thinking of doing away with the Pot as both my DAC and SQB Touch have volume controls.

 

[Zen Mod]

can't go wrong looking at post #1

most left , 50K

though , if your sources are capable of driving it , you can go lower .... to 10K

or , delete it from schm , as is adequate for your case

 

[DQ828]

Yeah, I'm not sure me looking at a schematic helps me work out the input impedance or output impedance

 

[Zen Mod]

input impedance is practically 110K , sans volume pot

when volume pot used , Rin is roughly value of it

output impedance is roughly 1/S , where S is xconductance of JFet used

in case of 2SK170BL , S is 22mS , so 1/22mS= 46R

NB that S , when JFets are in case , is marked ad Yfs

me , being toob guy , used to call it S

 

[DQ828]

Ok, just so I got this right;


Without the POT and feeding the signal straight into the 10uf cap the input impedance is 110k


If I use a 50k POT the imput impeadence is 50k


(I had to look up "sans" )

 

[qwertyl]

Europe Christmas group - first batch shipped: click here

 

[Soundhappy]

Europe Christmas group - first batch shipped: click here

Wonderful work Qwertyl Thanks!

 

[delecoy]

Under construction

Now that I'm adequately caffeinated, going to get this thing going. For convenience, I ordered up one of these from Mr. Broskie:

Phase Selector switch & PCB for switching between plus-mute-minus

One of many useful things for sale on his site. This new version also has a mute which should be handy for powering up and down.

 

[Zen Mod]

from when is Korg B1 balanced ?

 

[delecoy]

Its not. I thought I could still use it....but I've been wrong before. Many times

 

[Zen Mod]

welcome to the club

though , it's always nice , later, finding something you need , already in the drawers

 

[delecoy]

That's for sure! Though at this point I'm not sure whether my parts pile is an investment, a stash or a hoard.

 

[Zen Mod]

when parts are in case , nothing wrong with hoarding

 

[TungstenAudio]

A while back I bought two pairs of Edcor chassis mount transformers, WSM600/600 and WSM600/2.4K. I was thinking of splicing them onto the output of the earlier non-Korg B1 to get some gain and/or balanced outputs. I would like to drive either a pair of ACA monoblocks or my eventual Aleph J. The NuTube gain stage seemed like the perfect addition to this wackoo scheme, so I jumped on the Xmas offer.
The tentative plan so far is to hook up a pair of transformers to the JFet output and drive XLR cables directly from those into the amps. Just crazy enough? Or too crazy?

 

[Zen Mod]

right crazy

 

[avdesignguru]

You could add a high quality output transformer like a Jensen JT-11-FLCF to balance and isolate the signal ahead of the Glassware polarity reversing switch.