B1 Rev. 2

Here's my version. Board files will be published soon if anyone's interested, just need to do a bit more testing and compile the files :)
 

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Interesting. It would be interesting to hear your listening impressions between WLS and the B1.
I will update along the way, and if it all works from the get go I’ll post something during Christmas. I’ll be powering it from Gaz’s regulated bipolar PSU, much alike the Whammy PSU. I don’t have the neg Salas board yet, but I think I will get a good impression of the circuits potential :)

Toshibas are 10mA IDSS. So they’ll dissipate approx 120mW @ 12 volts. But I might not want to lower the PSU as far as 12 volts, it reaches 21 max. Maybe I’ll settle for 150mW, and perhaps sink the JFETs if they run hot. I have TO-92 sinks.

Edited to add: I really love the WLS. Fantastically clear and liquid. But it is way to gainy for my F2J, like mentioned before. So wanna try a buffer, capless this time. Dreaming of the IP, but this is less expensive. Had all parts except for an Adafruit @ 5 bucks.
 
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I had ringing issues when I used ir with a pair of LaScalas. Apparently. Other than that I haven't had any issues. I did put a piece of dampening material (a square of weatherization tape. Somewhat thick stuff) on the chassis of one. Dampening the chassis seemed to help.
 
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Interesting. It would be interesting to hear your listening impressions between WLS and the B1.
Immediate impressions, after just a few songs, apart from very improved gainstructure, is:

1: Even more relaxed and smooth midrange. Especially noticeable on female voices, for example Eva Cassidy. This means it is possible to play even louder without it ever getting harsh or making my ears oscillate :rofl:

2: Very good bass, it is just as good as the WLS, perhaps even more natural? Hmmm

3: Highs are very relaxed, but also extended. The WLS still has the upper hand on overtones, but it is too early to tell since I only use pin sockets for JFETs and pots, whose wipers conduct the output signal. Also, the WLS does have better cabling drive capability (large output devices), so shortening them through a change in chassis layout might inprove things even further.

4: A tad more natural and relaxed. This might be due to a bunch of factors, including things I did or did not do with my WLS (matching, etc). But, given no feedback and extremeley low number of parts, there are several reasonable explanations.

Both are winners, but in my system I think a buffer is the way to go :)
 
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Very cool! It sounds like it would be a fun and worthwhile little project. How does the imaging compare to the WLS?

When I assembled my 2nd WLS preamp, I matched everything with a little transistor tester to get the closer performing components in pairs. However, I didn't try to match the SMDs because I am not a masochist. Surprisingly, things were pretty close which is likely due to them being bought in bulk originally.

My first WLS board that I assembled, I didn't go through that effort. I did not hear a difference. between the two.
 
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