Wayne's BA 2018 linestage

[andynor]

Coloured wires are so anti-woke.

 

[rolandong]

Sorry if this was already asked and the answer can be found in 42 pages of this thread.
If I'll use this BA2018 as line stage for DAC or pre-amp (not driving headphone),
do I lost any output/voltage swing if I just retain Q8/Q10 (don't replace alternate output) with bigger TO-126 ?

 

[andynor]

Swing is not affected.

 

[_Bert_]

Hello, I'm very much interested in building Wayne's BA preamp. My question is, what are the specs for the volume potentiometer? I've got a brand new Alps 100k lying around...

 

[william2001]

6L6 has some advice about that <here>

 

[Leeuwarden]

Hello, I'm very much interested in building Wayne's BA preamp. My question is, what are the specs for the volume potentiometer? I've got a brand new Alps 100k lying around...

I used a 10K stepped attenuator first then switched to an Academy Audio muses. Difference was more than huge. Succes met bouwen!

 

[_Bert_]

Okay, 10K it will be, thanks en dankjewel 🙂

 

[gary s]

A question for Jim or Wayne, finally getting around to building this pre, I got an early kit that has 2SK209GR grade Jfets supplied, but I notice the latest schematic in the store page is showing 2SK209BL grade. Had a quick scan of the thread,but did not see any posts on this.

What is the correct Idss grade for the Toshiba 2SK209 for this design?

Thanks in advance guys.

 

[andynor]

GR is fine. They will run at approx 3mA.

 

[gary s]

@andynor - thanks for the confirmation.

 

[andynor]

There is a post regarding this, from 6L6 and some other(s). It has been built with both grades, with success. So if you got the kit from the store, I would just use the provided ones.

 

[gary s]

Jim (6L6) has also confirmed by PM, that the store only sent out the GR grade from day 1.

With the thread 209 pages long, I gave up looking for any further details about the Idss grade.

 

[_Bert_]

Okay, 10K it will be, thanks en dankjewel 🙂

 

[_Bert_]

For me it's not clear how to connect the psu. I have this new toroidal transformer that I never used. It has 2 x 15 volt AC. Actually the voltage is a bit higher, 17 volt. So I need a rectifiers for DC power. How do I go from 2 x AC to 2 x DC with 3 cables (one for ground)? Most images here I can't follow the cables. I should take the ground from the case? Do I need a ground protector loopback?