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Showing content with the highest reputation on 11/12/2019 in all areas

  1. 3 points
    He opened with Gandalf - with the section with the Balrog "Fly, you fools!". Then he hauled Glamdring out of a massive box on the stage - and the pointy hat - he was given both at the end of the shooting. He then got a young person from the audience up on stage to draw the sword, and signed a program for her. No Magneto though.... He did make a comment about Dumbledore though. Apparently Michael Gambon (who played Dumbledore) was frequently mistaken for McKellen, and asked for an autograph - so he didn't disappoint the fan and signed it "Ian McKellen". We're lucky enough to have seen him on stage quite a few times, most recently (2017) in King Lear in the 250 seat Minerva theatre in Chichester. Also Richard III in Bradford (1991), Waiting for Godot (in London with Patrick Stewart, 2009), No Man's Land (in London with Patrick Stewart, 2016), and a Godfather type of play translated from the Spanish called The Syndicate, again in the tiny Chichester Minerva (2011). He flew back from New Zealand during a break in shooting Gandalf in The Hobbit to do that. We've also seen Stewart, again in the tiny Chichester Minerva. The best Macbeth (2007) I've ever seen by a mile, that then went to the West End, then to Broadway, and then was made into a movie. And a not so good Twelfth Night as Malvolio (2007). In fairness he was miscast as Malvolio. And in a rather weird play called Bingo that Stewart is obsessed with (2012), about the late life, and death of Shakespeare, and the family squabbles around his death bed about the will. This is an outtake from the superb Macbeth movie. Follows the stage play perfectly, including the goods lift you can see in the background that Banquo's ghost uses to arrive. Get the DVD. If you like Shakespeare you won't be disappointed.
  2. 2 points
    https://lwlies.com/articles/david-lynch-tv-commercials/ The commercials of David Lynch. Even the wholesome pasta one feels disturbing.
  3. 2 points
  4. 2 points
    Started the day helping some neighbors build a work-around for a trail that an asshole neighbor decided to block despite it being a right-of-way. My buddy Jim got busy after I left and got the whole thing decked. So I got busy and made a sign for the new trail.
  5. 1 point
    That's OK, since Marc had 3 NUC's I read it more in the voice of Curly of the 3 Stooges 😃
  6. 1 point
    He should do the "I am not Dumbledore" tour.
  7. 1 point
    Black (sublime) is moar bettr?
  8. 1 point
    We'll catch up to you someday Ric... MOA XI --
  9. 1 point
  10. 1 point
    work in progress hangs off the side with thin angle bracket, no drilling of holes
  11. 1 point
    You're right about the LV supply (Stax did stick in some zener diodes to sort of regulate it), but this was meant to be a simple mod. It is intended to be bang for buck, and the most significant improvement is the constant current mod. Yes the power supply could be much better, but the constant current mod is a first order improvement, the power supply is a second order improvement. The intended audience wasn't the Stax Mafia, it was people who have a Stax amp and want to improve it without going to the expense of a KGST level amp. Or are just getting into Stax and are willing to do a little DIY (or have it done for them). I think more people would be interested in Stax if they could buy a $500 used amp, put $100 and a few hours work into it for some significant improvements, instead of spending a few thousand for the amp. Not everyone is interested in building from scratch. Actually, I didn't comment on the bias supply as I was not aware that was an issue, but now that I look at the schematic, I see that there should be a 5 megohm resistor after the last capacitor for protection. Damn!
  12. 1 point
    There seems to be some consensus on the voltage requirements for electrostatic headphone amps. Nearly all of the commercially available designs put out between 1000 and 1600 volts peak-to-peak, a range of about 4 dB. The legendary Stax SRM-T2 was specified to put out a bit more, close to 1800 volts peak-to-peak, which is 1 dB higher. This would be equivalent to almost all loudspeaker amplifiers putting out between 50 and 125 watts, with the T2 being like a 160 watt amplifier. However, there hasn’t been much discussion on the current demands for electrostatic headphone amps. Output stage currents in commercial amplifiers have run between 2 mA/channel (Koss ES950) and 36 mA/channel (Blue Hawaii). Back in 1978, Nelson Pass published in The Audio Amateur (issue 4, p. 12) some measurements he had done on the slew rate of music signals. He tried out various cartridges and LP records, and using a 100 watt amplifier with a 30 volt/microsecond slew rate, reported that the highest slew rate he found with music signals was 1.5 volts/microsecond up to clipping levels. The late Peter Baxandall also published some years ago in Wireless World that music signals required an amplifier slew rate sufficient to drive a 6 kHz sine wave to clipping with low distortion, which works out to pretty much the same thing. A 100 watt amplifier has a peak-to-peak output of 80 volts. The Blue Hawaii, to take a current state of the art amplifier, has a peak-to-peak voltage at clipping of close to 1600 volts, which is 20 times higher, so the fastest music signal would have a slew rate of 30 volts/microsecond when the Blue Hawaii is driven to clipping. So how much current does an electrostatic headphone amp need to produce a slew rate of 30 volts/microsecond? A typical electrostatic headphone approximates a load of about 100 pf - Stax specifies most of their current models between 94 and 120 pf. The amount of current required for 30 volts/microsecond into 100 pf would be 3 mA. This is the amount of current that the amplifier has to supply to the headphones alone in order to play the fastest music signals up to clipping. Since amplifiers don’t sound their best at the very limits of their capability, for any real amplifier, there should be additional capacity in both slew rate and current over the bare minimum required. John Broskie has suggested on his TubeCAD website that for low distortion the maximum signal current demand on a tube be a fifth of the standing current. This calculation also assumes that the amplifier itself does not consume any signal current. But that is not always true. Take the Egmont, a basic, inexpensive tube electrostatic amp circuit. It uses 66k resistor loads in its output stage. With +/- 260 volt supplies the output stage runs at 7.9 mA current. If we drive the headphones to 1000 volts peak-to-peak using our fastest music signal the headphone consumes 1.9 mA, but the resistor consumes 7.6 mA, using all the current the output stage is theoretically capable of supplying. The reason that an amp with a total current of 7.9 mA can supply both 1.9 mA to the phones and 7.6 mA to the resistor loads is that the current to the headphone is approximately 90 degrees out of phase with the current to the resistors – remember the geometry of a right angled triangle? The headphone and resistor compete for the available current, and since the resistor is lower impedance than the headphone, the resistor hogs most of the current and the headphone is left with the scraps. Furthermore, the amount of signal current soaked up by the resistor depends on the magnitude of the signal, whereas the amount of current going to the headphones depends on the speed of the signal, so the ratio of 1.9 mA to the phones and 7.6 mA to the resistor is even worse almost all of the time. In fact, this is a problem for any electrostatic headphone amp that uses resistor loads in the output stage since the resistor sets both the standing voltage and the standing current. Massively increasing the voltage and current so that no user will ever come close to reaching its limits doesn’t really solve the problem, it just pushes it farther away. And then, a further problem is that devices and components which can withstand that amount of voltage, current and power are expensive, which rather defeats the goal of an inexpensive design. Now, take my revision of the Stax SRX tube design using current loads. The output stage runs at a higher current and voltage: 14 mA current with the power supplies run at +/- 325 volts. More importantly, the cascoded current loads on each plate measure over 160 megohms impedance, thus requiring a mere 4 microamps to drive them to clipping, so 99.9% of the total standing current is available to drive the headphones. The maximum current required to drive the headphones at clipping is about 2.4 mA, less than a fifth of the current available. To further illustrate the value of a good current source, let’s go back to the Egmont. With the output tubes in that design delivering the same peak signal current of 2.4 mA, it would produce about 300 volts peak-to-peak with about 2.3 mA going to drive the resistors and 0.6 mA to the headphones. For the same signal voltage into the headphones, the Egmont output tubes have to produce 4 times as much signal current. Now these are “back of the envelope” calculations. But at least, now we have a reasonable estimate of how much signal current an electrostatic headphone needs to faithfully reproduce the fastest music signals. And, it is clear that replacing resistor loads with current sources is a much more efficient method. Finally, let me make a brief comment about a related matter. It is sometimes said that electrostatic headphones require voltage but no power. This is false. It is true that electrostatic headphones resemble capacitors, and with a capacitor, the drive voltage and current are 90 degrees out of phase so that no power is consumed. However, remember that a capacitor is a simplified model of a stat headphone. In fact, electrostatic headphones have to consume energy, because we can hear the sound they produce! Sound is a form of energy, and by the law of conservation of energy, one of the most fundamental laws of physics, that means the headphones have to consume energy.
  13. 1 point
    Sure. The equation relating capacitance, charge and voltage is: V = Q/C where V = voltage, Q = charge and C = capacitance Taking the time differential of both sides we get: dV/dt = (1/C)*dQ/dt where dV/dt = voltage change/time = slew rate, dQ/dt = change in charge/time = current = I So: dV/dt = I/C, or C*dV/dt = I For my example, dV/dt = 30 V/microsecond, C = 100 pf, plugging everything in gives I = 3 mA for 1600 volts peak-to-peak. I used to be a physics major in a previous life. ) The reason you got a different answer for slew rate is that you are calculating for a full-power, 20 kHz signal. However, music does not contain full-power signals at 20 kHz. As Nelson Pass and Peter Baxandall found, the music power spectrum rolls off above around 5-6 kHz at a rate of approximately 6 dB/octave. Because of this, for a 100 watt amp that can swing 80 volts peak-to-peak the fastest slew rate with a music signal is 1.5 volts/microsecond up to clipping, whereas a sine wave 20 kHz signal at clipping would slew at 5 volts/microsecond for the same amp. The fact is that music signals are not that fast compared to some test signals. Multiply those results by 20 for a 1600 volt peak-to-peak signal at 20 kHz gets you to 100 volts/microsec, which is what you calculated, or 30 volts/microsecond for music signals, which is what I got. You'll get the same answer as me if you plug in a full-power signal at 6 kHz, which is what Baxandall said was needed to reproduce music. Now, the calculations in the second post assumed a signal of 800 volts peak-to-peak, which is 400 volts peak, whereas your calculation was for 800 volts peak, hence your answer is twice as high as mine. My number also includes the 1.5 mA current into the capacitative load of the headphone, and because that current is 90 degrees out of phase with the current to the resistor, the overall answer 8.1 mA (rounded off) rather than 8 mA for the resistor load alone.
  14. 0 points
    Scheduled a boiler cleaning after I had to cancel the previous one last month. The company is now booking for January of next year. I'm on schedule for the 29th. I also called an outfit that cleans chimneys to do a cleaning and inspection of my mine. It's got a stupid cap on it that is so clogged with creosote that I can't burn at all. Fortunately, the chimney outfit is booking much sooner ...Dec 4th. UNfortunately, it's dropping to 10º tonight. Lastly, I called the guy who replaced my well pump last fall. I don't know if I mentioned this, but a pipe he worked on had a cap that blew off a month ago and flooded my basement, taking out some of the electrical wiring. I'd be more upset about this, but the entire house is a teardown at this point. Home ownership is a lesson in constant expense. I'd bitch more about it, but I see what people pay in rent for a shitty two bedroom apartment and I conclude that I get off "easy."
  15. 0 points
    I thought I would post this here because it seems appropriate. Cassius Winston is the All American point guard for the MSU Spartans. His brother Zachary stepped in front of a train (intentionally) on Saturday night. I am deeply moved by Cassius's instagram post. This young man gets it. Every day we talk to someone who is hurting, fighting for life, facing demons. Treat others well. You may be all that stand between them and death. Cassius Winston pens emotional message to brother Updated 1:28 PM;Today 11:39 AM AP Michigan State's Cassius Winston, center, stands with teammates during a moment of silence in honor of Winston's younger brother, Zachary, before the team's NCAA college basketball game against Binghamton, Sunday, Nov. 10, 2019, in East Lansing, Mich. Michigan State won 100-47. (AP Photo/Al Goldis) 15 236 shares By Kyle Austin | [email protected] Cassius Winston stayed silent on Sunday night as he played for Michigan State less than 24 hours after the death of his younger brother. In the hours after the game, he took to Instagram to post an emotional message to his brother, Zachary, who was struck and killed by a train in Albion on Saturday. Police say they believe he intentionally walked in front of the train. Here's Winston's message to his brother in full, marking his first public comments on the situation: Ima put this on here cause I need you to read it, and I feel like this the best way for it to get to you. I love you bro, w everything I have in my entire body. I love you so much, if I could carry yo pain I would wear it on my shoulders just to see you happy and wouldn’t think twice. I understand it was to much, I understand I really do and yo story won’t end here. I can promise you that, the next time I run into someone in your situation ima save them, cause that’s wha you would want me to do. I wish it was a term that goes deeper then brother, cause that’s what’s you are to me, 1/3 of my heart. And I’m struggling because there is nothing that can replace that Smoothie. I need you, I miss you. But I’m so proud of you, bro you fought every demon w everything you had in you. You went to war w yourself every single day not knowing if you could win that battle. And you won time after time. You stood tall and you let your family love you, you gave me everything I asked for, just one day you didn’t have enough strength. And that’s ok man, that’s really ok, ppl can’t go through wha you went through, you are the strongest, wisest, kindest, most caring person. The best brother/ gang member I could ever ask for. And I wouldn’t replace you or change any single thing about you. Not one. I don’t like doing these cause I feel like they for show, but I need to you to read this Smoothie and I need you to know, that I love you and I care for you. And the only reason I can sit here and still stand is because I know you not in no more pain. The only reason I’m still standing. After that bro we really got beef, and when I see you again I’m beating yo ass. Cause it’s no way you got me out here trying to adjust to life w out you bro. This shit so deep bro we suppose to see all this out together. But we’ll have that convo the next time I see you Smoothie Bean. Rest up my baby and keep watching over us, save me a seat. And when it’s all said and done ima have so much to tell you. You gone already know but ima tell you anyway. Love you Gang member🖤 wish your story coulda had a diff ending, it’s ok tho enjoy it up there. Ima see you soon enough #LuvSmoothie🖤