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Qobuz finally has this one.

Not sure if this is already widely known, but Cookie Marenco heard Laurie Anderson mention it, then did post to tell others. Radio Garden is a very cool app where you scroll the Earth to find radio stations. So currently listening to: http://radio.garden/listen/yumi-fm-93-0/aMOv7kiE Here’s a good starting point: http://radio.garden/playlist/rare-tongues/9M0t3goK

Oatmeal Johnny has settled in pretty well, a couple months in. He has slotted straight into “like Dunhill, but young.” Even Silver would agree, I think.

Some internet history right here: Democracy Manifest. Does contain some, ahem, dental gore.

I'm going to have a side project called, "God's Won't".

Totally missed this – thanks, everyone!

Although the KGST uses the same front-end as BH and Carbon, its simplicity comes at a cost. In the 'stock' form, the open loop gain is about 78dB and closed loop gain about 59dB. Having only moderate global NFB means that the circuit has to have a wider open loop bandwidth and good linearity to begin with. It also suggests that the measured performance would depend a lot on the matching and inherent linearity of the tubes. Below is the THD+N vs amplitude plot I did earlier on the 'stock' circuit. The max output is about 200V. It kind of falls short for an amp with ±400V supply. With the experience from the pentode experiment on Carbon, I tried a few pentodes and tetrodes with the 'stock' circuit. The first one I tried was the 6973. Why 6973? Because it's pinout is very close to the 6S4A, such that I didn't even need to cut any PCB trace in order to use it. The result was quite ok. The max output went up to 500V and the lowest THD reduced by about a half. Knowing how much the 6973 costs on ebay I think I should have a better use for them 😉 Then I tried a few others, including the 832A. It has one of the cutest bottles and yet is not that expensive. I was eyeing on the Breeze audio 832A SE amp enclosure. The box may look hideous to some people, it would be really cool to have a unique eStat amp like that - if still offers reasonably good performance. The 832A didn't pan out very well. The THD flattened out at 0.01%-ish, mostly 2nd harmonic, due to the mismatch between the two tetrode sections. Some people may appreciate the 'tuby' sound, I decided to move on. I looked for a triode with amplification factor of 30 (twice that of the 6S4A), which also allows 400V DC on the plate (800V peak). It's not that easy to find real triodes like that, unless I go with the exotics such as the 801-A/10Y. I heard about the 12HL7/12HG7/12GN7 family. The video output pentodes designed for the color TVs in the late 1960's. They allow 400V on the plate, have a mu of 30 to 50 when triode-strapped, and said to have great linearity. Below curve was captured with one of them at X=100V/div, Y=5mA/Div, Vg1= 2V/step It turns out (again) it's not easy to find well-matched pairs because the curves in the high voltage region vary a lot from tube to tube, and the g2 power would be over spec when triode strapped idling at about 400V. I did get some nice distortion plots when they are wired in pentode mode (below FFT with 12HL7 at 100Vrms output). Unfortunately not all of them are happy with 800V peak on the plate, although 400VDC is okay on paper. So I came back to the drawing board, trying to make it work with the 6S4A. In the 'stock' circuit, the limiting factor to the output swing is the signal amplitude at the 6S4A grids. Adjusting the ratio between the 200K/6.8K resistors on the active loading NPN pair can increase the idling voltage and improve the max swing into the 6S4A. The downside is that the output impedance of the driver stage will increase, and the open loop bandwidth drops a bit due to the Miller caps on the 6S4A. Also I don't need the full 60dB gain. '200mV sensitivity for rated output' was established from the analog-era when tuners and tape decks are the most popular sources, not to mention 100mV for rated output. Doubling the resistors at the source of the input JFET aught to do it. The end result is extended output swing: And a not super clean, but still okay output FFT spectrum at 100Vrms. Well, that seems to be the best I can do. I'd live with(in) its limitations, close the lid and enjoy the music!

The first mini rock opera. During the whole melee, John Entwhistle just stands still and plays the bass until he does the last verse in falsetto. If you haven't watched The Kids Are Alright, you should. Many more examples of Moon Madness and all the rest. Great interview breaks, including Keith and Ringo both totally lit. I've posted it before, but this is me and my Whomobile about a year after watching The Kids Are Alright when it first came out and months after my first Who concert where I spray painted the logo in the Oakland Arena parking lot.

Slightly different energy.

Godspeed, Olivia. Thank you for my prepubescent crush... HS

Saw Grease when I was 10 and Sandy Olsson gave me some completely new feelings. Olivia seemed like a terrific person in real life too. RIP.

R.I.P The luminous Olivia Newton-John https://www.bbc.com/news/entertainment-arts-62472100 and a live tributes timeline ? https://www.bbc.com/news/live/entertainment-arts-62470505 https://www.hollywoodreporter.com/news/music-news/olivia-newton-john-dead-grease-1235194880/ https://www.nytimes.com/2022/08/08/arts/olivia-newton-john-dead.html https://www.billboard.com/music/music-news/olivia-newton-john-dead-obituary-1235123935/ https://www.hollywoodreporter.com/news/music-news/olivia-newton-john-dead-grease-1235194880/ R.I.P Olivia

This is what the thread is about. Detroit Style Pizza! With a BIG pepperoni. 🤩

Homework! The interview I had earlier this week gave me homework, so that's a good sign.

Finished, with minutes to spare a set of these. Kasia asked, of course, why there are two openers on each and the answer, of course, was because this is fucking Head Case. and not that I gave fuck all thought to where screws were coming through the front when laying out the keyholes in the back

Well, Nutella cost us $1,300 and counting today. Against our better judgement, we left some party decorations up for Piper’s birthday week. Found some chewed pieces of plastic streamers on the ground yesterday morning, and she didn’t finish her breakfast so I feared the worst. After multiple rounds of vomiting, including parts of streamers, she spent much of the day at the emergency vet. Long-story-short, looks like she’s going to be OK without surgery. I’ve admittedly been a bit of a mess… It was not a fun night, or enhaoyable day waiting to hear. And everyone was determined to welcome her home.

No need to justify, Justin. I know the work deserves a high price tag - I'm just trying to determine how much money to set aside :). The power question is because I have no idea anything from an engineering standpoint. I'm just trying to gauge from a tier standpoint is this like a T2 level amp or more like a megatron... etc

It's more power than BHSE, but not by much. There isn't really much point. There are already several competing tube amps that put out less voltage swing than STAX's entry level amps. Pushing the envelope on component specs to achieve another fraction of a dB more output wasn't the goal. as for the price, well over 10k. there is absolutely no way this amp wouldn't be. I could exceed that in bill of materials easily. How much is the MSB, 40k? The Sennheiser HE1 w/ headphone is $59k. The Shangri-la Sr w/ amp is $50k. This will be much, much less than either of those and sound better with SR-X9000 or CRBN.

I was able to bring the other channel to the same THD+N performance. While I was at it, I tried the current production low-noise JFET from Toshiba, the 2SK209. The first 2 from the cut tape matched really well at 5.9mA Idss at Vds=10V. I'm surprised that I was able to do it without using the microscope or magnifying glass (pardon the flux residue though). I guess I no longer need to pay the hefty price to get the LSK389 or the obsolete K170s. Regarding jacking up the bias of the SiC FET, it has its limits. The original bias resistors set the SiC FET G at 450*20/(175+175+20) = 24.3V to B- with a -450V supply. After adding 260k in parallel with the 175k Ohm resistor, I was able to set the G at 27V to B- with a -407V supply. Note that the VGSmax for the G2R1000MT17D and the C2M1000170D are 25V, and is 23V for the MSC750SMA170B. So I'd better dial it back a little. In normal operating conditions, the voltage on the 20k resistor will never apply entirely to the G-S. But it kind of tells me how intricate the original design was, with all corner cases considered.

RIP Ben Stelter, a 6-yo who died of Brain Cancer. As a hockey fan, it was incredible to see the impact he had on the Edmonton Oilers, and the love they had for him. Fuck cancer...fuck it hard especially for attacking such young kids.... https://www.nhl.com/news/ben-stelter-young-oilers-fan-dies-play-la-bamba-baby/c-335242756

Issey Miyake Dies at 84 https://www.nytimes.com/2022/08/09/fashion/issey-miyake-dead.html Missed this a few days ago. Of significance for me as Erika had an Issey Miyake dress as her wedding dress.