Wayne's BA 2018 linestage

[devize]

Another line stage is born

Testing it with a 1kHz rectangular signal looks very promising.

Running it with 2 daisy chained PSUs at +/-14V. Looks also very good.

Next step: 2 GoldPoint virtual ground (VG2) as PSUs. The GoldPoint VG2 will
allow only for +/-14.5V at 30V DC input (my estimation).
Hope that this will work without clipping. Any experiences with this anyone? Would be glad to hear about this or 14.5 V in general..

Thanks to everybody here. This thread gave so much input for me.

Best regards
Detlev

 

[Mark Johnson]

Odd to see "50 ohms" displayed along the right hand edge of the output screen.

 

[Sadface]

Am I reading things correctly that this linestage is balanced in and singled ended out?

 

[6L6]

It can be run that way, yes.

 

[william2001]

This thing makes a fantastic balanced to single ended converter. My DAC is balanced so I took full advantage of that feature.

 

[margol]

Hi.
Have anyone compared the two output transistor options soundwise?

Also how does it sound compared to BA-3?

 

[6L6]

Yes. Can’t tell a difference.

I prefer the BA2018 to the BA3 preamp but they are very close.

 

[avdesignguru]

I built two BA2018, one with and one without large outputs. Set up A-B switching and did careful gain matching. I could not hear a difference.

 

[PJN]

I also built two ba2018 preamps but with different psus, one with a salas ubib shunt psu, and another with an inexpensive chinese studer900 clone psu. The sound quality between the two is close, and excellent on both builds. The salad shunt build is better but it is a very small difference.

 

[devize]

Am I reading things correctly that this linestage is balanced in and singled ended out?

What I wanted to build is a non balanced version. When I later tested it with real audio signals I noticed that I made a mistake connecting the outputs. I have no clue, why the scope showed the correct signal. However, it masters music very well.

 

[william2001]

I never did build the BA-3 but definitely prefer the BA2018 to my BA-1/BA-2 front end that I used as a linestage for awhile.

 

[pfdavid]

I, thirdly built two BA2018s, one with and one without the large outputs. Without version is servicing my 2017 V-fet, most excellently.
Glad to hear they'll sound the same.

 

[henryve]

I also built two ba2018 preamps but with different psus, one with a salas ubib shunt psu, and another with an inexpensive chinese studer900 clone psu. The sound quality between the two is close, and excellent on both builds. The salad shunt build is better but it is a very small difference.

I would not expect a well designed audio circuit to be influenced much by DC fluctuations.

Many times I think we do this (adding DC regulation) because it makes us feel better and because we can. I for sure like to add DC regulation to small signal audio circuits if I can because it seems more complete, but I do not for one second believe that my ears are good enough to hear any improvement it might make.

 

[andynor]

I finally got to working on the WLS tonight, as a generous package of JFETs arrived in my mailbox yesterday.

It is not my purpose to brag, but I wanted to share a pic of the first soldered JFETs, because I am proud of having made it with a seemingly OK result. Looking forward to the rest of the build!

Cheers,
Andreas

 

[Zen Mod]

as I wrote somewhere (did I?) , solder flux (liquid helper) is main trick

 

[andynor]

You are never wrong, Mighty. Even when you are, you’re right. But are you ever wrong? Don’t think so.

I used big fat weller solder paste/grease, the thick and chunky stuff. Worked like a charm. A little cleaning, but well worth it. Went rarher quickly once I found my way of doing it.

 

[cubicincher]

to Andynor #2236

Hello Andreas,


soldering on the JFets is looking good and well aligned.
Continue going the quality - work - road....😉


Greets
Dirk

 

[andynor]

Thanks, Dirk! Really appreciate it!

 

[twitchie]

That is very well done Andreas!

You can absolutely brag about that!

 

[andynor]

Thanks guys! Really appreciate it.

As I neared completion, I discovered that the shopping list used from this thread, lacked 4 transistors to complete the small output stage version. I lack two 992s and 2 1845s to finish the preamp.

And... both Mouser and Digikey are sold out.

Anyone by any chance have some leftover transistors to send me?

I should obviously have double checked... but here I am.

Regards,
Andy