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More Than A Feeling by Boston (1976) Because: There is a lot going on, and it was all done in the analog domain. impressive. So crank it up, and sing along like no one is watching / listening. You know you want to. Tariff Free!

finally. higher signal to noise ratio, more than 110db. takes signals up to 20 volts peak to peak unbalanced, 40v peak to peak balanced. no input attenuator that adds noise for those stupidly high voltage dacs. ( requires 30v power supplies) (volume control in the middle) thd about .005% no feedback. work in progress 4 layer board. preamp2025f.PDF

After watching this: I thought I might try to make my latte look like something. I have never really cared in the past. After a two failed attempts during the week, I didn't have my foam right. Today I made a thing. Not great - but still drinkable... that's all...

I think you're right-- thanks for picking up on this. I do still think it matters; if the CM signal is getting converted to DM, the system's CMRR will be limited, no? Bill Whitlock of Jensen makes a big kerfuffle about balanced impedances. Here's an AES presentation that you may have seen. It's a bit goofy, but gets the point across. https://www.aes.org/standards/webinars/AES_Standards_Webinar_SC0505_20210726.pdf If I'm being honest, I didn't realize there was a CMRR test. 😁 I'll be using this more often. It can't do sweeps and I don't think it can append results in APx500 v4, but here are some results tested at 1kHz with a 1VRMS signal. I tabulated some data at different positions. Looks like there is a "sweet spot" with the conventional pot hookup, whereas the shunt pot does very well once you clear the first few degrees of rotation. Position Shunt pot CMRR (dB) Series pot CMRR (dB) Min 50.800 16.024 77.772 23.607 89.748 27.03 99.328 29.009 98.410 30.802 97.917 39.849 97.656 73.718 97.362 67.308 97.228 40.310 96.271 35.341 95.442 30.717 94.715 32.493 94.031 45.187 Max 93.844 86.054

The distance from earth to AC and other components is scary small there. I'd at least put in isolation slots as the voltage can creep over the PCB.

I may be a hack, but I switched from using 4-gang pots to shunting stereo pots because I think they work better. A big part of the reason why I would build a balanced circuit is to benefit from its CMRR (and even order distortion cancellation by proxy). I measured the matching between gangs on a 20k RK27; it's better than the specified 20% tolerange, but it's not great. Here are some measurements at arbitrary rotations. Gang A Gang B Matching 51.4 51.6 0.4% 255.7 252.8 -1.1% 623 624 0.2% 1299 1300 0.1% 3042 3089 1.5% 4230 4368 3.2% 8470 9080 6.7% 14680 15420 4.8% 19100 19930 4.2% 19900 20380 2.4% The matching is directly proprotional to the CMRR. So I took a measurement of CMRR using the following circuit. The idea is that this simulates the balanced input of an amplifier and will tell us how balanced things actually are. Not very, it seems. Each trace is a different rotation angle on the pot, with the -115dB one being with the signal fully shunted. (There is some resitual resistance with the pot at 0.) -35dB of CMRR will significantly degrade an amp's performance. I repeated the measurements with a shunting pot configuration, using Yageo 1% 2k resistors and the same 20k pot. Although the AP input capacitance degrades CMRR at high frequencies, even the worst 1kHz measurement is about 12dB better than the best measurement with the series pot. The low frequency degradation is most likely caused by the AP's 1/f noise-- we're measuring microvolts at this point. If I wanted to further improve performance, I'd use resistors with better matching. The Vishay ORN arrays are available in 0.01% and would probably be my pick. LT5400 isn't bad either. https://www.mouser.ca/ProductDetail/71-ORNTA1001ZUF I don't know that this is necessarily relevant to the design in the first post-- looks like it doesn't use a pot at all-- but the circuit has its place.

Welcome back! So sorry for your captivity.

Two quick listens. Chicken Heads 50th Anniversary by Bobby Rush (2022) https://open.qobuz.com/album/p1a5wnkma1tzb Example: Just 4 versions of the same song: Bobby Rush, Buddy Guy, Gov't Mule, Christone "Kingfish" Ingram... I like Bobby's more raw blues, but the others are fun. And then more fun. A lot of things still hit: "Well, he may be a fool but he’s our fool" Good Old Boys by Randy Newman (1974) https://album.link/fw6p7j6rpszzd Example: Some really pretty tunes along with the hard hitters.

the idiot at eddie current was big on that circuit. and did that on his electra. and then tried to get too much gain out of it. and the tubes went into saturation and then you have to hand pick the tubes etc. biggest problem with that one is the 100k pot starts off with 2nv of noise all by itself.

Thanks @skullguise and @guzziguy well yea, we still got cats hanging around in our garden, unfortunately nearly all of the cats I was familiar with are gone considering stray cats life expectancy and the amount of time I was "gone". 2 of our family is gone too. One of them, Pamuk died cuz of FIB, other one (Şirin's son) Duman cuz of pneumonia. But my father took good care of them while I was "gone". I'll post pics from our garden shelter soon. And thanks for the warm welcome back guys. I thought I won't be remembered. And title system changed i guess, I lost my beloved title.

Multiple by Joe Henderson (1973) https://album.link/tgfvb24bkbtbt Example: Goes a little far now and then into the 70 experimental jazz, but always keeps it musical. I did really enjoy this outing. Lots of flavors to enjoy.

Joni Mitchell - Ladies of the Canyon Hiromi - Out There

I was going to wait longer to post until I read further, but, at least today it's (Kindle and Apple Books versions) $1.99 (of course after I just paid $14.99 three days ago ) and one of the sources for the Martyr Made podcast I recently mentioned. Should any recent government actions make you daydream about resistance (ex. SDS, The Weathermen, The Symbionese Liberation Army, The FALN, The Black Liberation Army, etc.), even if sometimes ineffective, dangerous, or misdirected, give Bryan Burrough's Days of Rage a try. So far so good. https://www.amazon.com/dp/B00LFZ84PC?_bbid=259687172&tag=bookbubemail1-20 https://books.apple.com/us/book/days-of-rage/id895204913

Based on the recent @mikeymad Casual Jazz/Gleason post in the music thread.

I loved Norm and love Anthony Jeselnik. They found out during the recording of this about the news. Norm hurts a lot more than most I've seen lately.

Trending #2 - right behind the Apple event. (edit - Trending #1 - over apple) And this was a clip that I was looking for.

What about his famous Bob Saget roast when he confused everyone? Ran from nasty all the way back to the 50s.

I cannot remember why - but I literally watched that in it's entirety two weeks ago (not knowing his condition). RIP again to Norm, for being relentless and fearless.

Better Than Ezra drorpped a beautiful tweet which has one of my favorite jokes of all time. Fuck cancer, as they say.

Rest in peace, Norm. Goddamnit he was funny.

he was my favorite comedian for a very long time.

RIP to a fearless storyteller.

This is a shitty copy of what I consider to be one of the best jokes of all time, and what I think about when I think of Norm.

Godspeed, Norm. Thank you for all the belly laughs... HS

That really sucks. Almost ten years battling cancer without ever disclosing it. RIP Norm

https://www.tmz.com/2021/09/14/norm-macdonald-dead-dies-cancer/ FUUUUUUUUUUUUUUUUUU RIP, Norm. You were one of my favs.

R.I.P. Norm Macdonald at 61 of cancer...