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change the input resistors to as low as possible compatible with what is going to drive it. 10k is probably what i would do.

The Outlaws (Prime) - fun watch. We're through the first two seasons, looking forward the third.

A small update on the Super Carbon troubleshooting. After replacing the 5pF capacitor with the 470pF value shown on the schematic, the oscillation was reduced significantly. However, there is still a very noticeable background noise. At this point I'm starting to suspect the XLR input stage instead of the power supply. When I short IN+, IN−, and GND together at the input, the background noise disappears completely. That makes me think the input stage may simply be too sensitive. @kevin gilmore do you think it would make sense to reduce R48 and R49 from 500kΩ to something like 200kΩ or 100kΩ? Or perhaps add a small capacitor for some RF filtering at the input? I'd appreciate any suggestions before I start experimenting further.

Condolences and ... just yeezh, that just sucks of a situation.

Condolences Brent and family. RIP Bones.

Thanks everyone for the kind words and thoughts. Talked to my brother today. Turns out he (Bones) didn't have life insurance, nor any preplanned funeral arrangements. Turns out it's going to be 4500$ to have him cremated, and none of us are able to swing it. This sucks, because it's just putting more and more stress on my mom. I can't even fly back to be with her right now since hurt my back a month ago and can barely walk some days, much less travel across the country. Glad I was able to go out a few months ago, but hate I can't be there now.

I am working on a CFA3 build where the original THAT340 input devices have been changed to a JFET input pair. For a rough simulation I used these models: .model 2SJ103 PJF VTO=-1.5 BETA=10m LAMBDA=0.01 RD=20 RS=20 CGS=50p CGD=45p IS=10p .model 2SK246 NJF(Beta=2.5m Vto=-1.5 Is=1e-14 Cgd=4p Cgs=5p) This is only intended as an input-impedance / loading check, not a final device-accurate distortion simulation. With the current SS input/feedback network: R24/R26 = 5k R44/R49 = 50k C9/C10 = 20p I get approximately: SS mode input impedance: ~11.7k ohm per phase at 1 kHz ZF mode input impedance: ~50k ohm per phase at 1 kHz So even though the input devices are JFETs, the SS mode input impedance is still relatively low because of the surrounding SS input/feedback network. The practical concern is that I changed the volume control from 10k to 50k. With a 50k attenuator, the source impedance around mid attenuation can be much higher than with a 10k control. That seems like it can load/interact with the ~11.7k SS-mode input impedance, while ZF mode is much less affected. I am considering scaling the SS input/feedback network values upward while keeping the same approximate ratio and compensation time constant. Current: R24/R26 = 5k R44/R49 = 50k C9/C10 = 20p Conservative option: R24/R26 = 10k R44/R49 = 100k C9/C10 = 10p Simulation: SS input impedance rises to ~20.2k per phase SS gain changes from about 15.0 dB to 14.7 dB More aggressive option: R24/R26 = 15k R44/R49 = 150k C9/C10 = 6.8p Simulation: SS input impedance rises to ~26.6k per phase SS gain changes to about 14.5 dB The idea is to reduce the current drawn from the volume control and raise the effective SS-mode input impedance, without changing the low-frequency feedback/input ratio too much. Has anyone tried this on a JFET-input CFA3, especially with a 50k volume control? Does scaling R24/R26 and R44/R49 like this seem reasonable, or is there a known preferred value set for JFET-input builds?

Another batch of chili. This one I'm talking to work tomorrow. This is my 7 qt. Dutch oven, so it's a big batch. If I haven't posted my recipe before: Dice two bell peppers (red & orange), and a medium yellow onion. Sauté in a lg. skillet. Set aside in 7 qt. Dutch oven. Brown 2 1/2 lbs. of ground beef in same skillet, salt and pepper to taste. Use slotted spoon to separate ground beef from rendered fat. Place ground beef in Dutch oven. In sauté pan add 16 Oz. can of diced tomatoes of choice, one jar of fire roasted salsa, small can of tomato paste, 16 Oz. Red wine, 1 tablespoon of Worcestershire sauce, tablespoon of minced garlic, spices ( I use Carroll Shelby's chili seasoning). Cook over medium heat until hot and well mixed. Add to Dutch oven, along with 1 can of pinto beans and 1 can of Black beans. Mix well and simmer covered for 15 to 20 minutes. If needed mix masa flour (included w/ chili seasoning) with 1/3 cup of water. Stir into chili, recover for additional 5 minutes. This will thicken the chili nicely.

Sorry to hear of your mom's losses Brent. RIP Bones

I can't believe I'm going to bore you all about Newton. Although English, he wrote Principia and Optiks in Latin. An that is a real problem - translating back into English is a tickly thing, particularly the more fundamental stuff which is to do with what we learn as Newtons laws of motion at school. What is the precise translation of momentum for example? After that the translators have an easier job. Newton derived all his proofs in his long book Principia geometrically, step by step. He finishes off by meticulous measurements of the motion of the planets etc. At one stage he says that a chunk of the measurements was lost, but he can recall the basic idea behind the measurement. By "lost" he actually meant that his dog ate some of the sheets, or knocked a candle over and set fire to some sheets. Accounts vary. As professor at Cambridge University, his lecture course was so unpopular that no students attended. But part of his job was to give lectures. So he'd turn up and give the lecture to an empty theatre. In later life he spent most of his time studying alchemy. I'll shut up now

Sorry to see of your mother's partner's passing, Brent. Godspeed, Bones.... Sam

So sorry Brent…. With my dad’s passing, some family and friends have been reflecting on mortality a bit. Many of us are experiencing that kind of thing, people our age up through parents’ age losing folks around them. One called it the worst curse of aging, and I can agree…. Wishing your mom and family the best!

My condolences to you and your family, Brent. RIP Bones.

Frozen Charlotte by Jack White (2026) https://open.qobuz.com/album/h83ak1ouymgjv Example: Lots of heavy riffs with a groove. Like it.

Condolences to you and your mother, Brent. She must be very sad and lonely. Life can be such a bitch…

RIP Dale Jones, aka Bones, aka my mom's husband. He had been dealing with dementia and was moved to a nursing facility the day before. We knew it was coming but she has lost her brother, sister in law, a close cousin, and now Bones, all in the past few years. Not many people left in the family and it's tough for her.

VJ Dave Kendall (of eMpTyV's 120 Minutes fame -- the 2 hours I watched the most on that channel) has died Paste MagazineDave Kendall, creator and former host of MTV’s 120 Minute...Paste Magazine is your source for the best music, movies, TV, comedy, videogames, books, comics, craft beer, politics and more. Discover your favorite albums and films.

Demented fermented - James Hoffmann discusses coffee fermentation:

Few more funz from the webz

RIP actor Hal Williams, who passed at the tender age of 91.

A.I. Enhanced Costco Brownies ATK Enhanced Banana Bread.

The New NPR. 🤘

Last week I finished assembling the Super Carbon, and it's now up and running. The first listening impressions are very encouraging, but there is still some audible background noise that needs to be eliminated. At the moment I suspect it's related to the power supply compensation, possibly an oscillation. On the schematic, around the STN0214, there is a 470pF/1kV capacitor. I initially installed a 5pF/1kV capacitor there, so it's possible the compensation at that node is simply insufficient. I'm currently waiting for some mica capacitors to arrive so I can experiment with the compensation network. While simulating the circuit in LTspice, I measured approximately 540V VCE across the STN0214. Based on that, I don't think the PBHV2160(VCEO = 600V) is an ideal substitute for the STN0214, especially if you're targeting output voltages significantly above 600V. On another note, I also performed the initial testing of the D&G 211 filament supplies, and they appear to be working as expected.