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Showing content with the highest reputation on 03/30/2019 in all areas

  1. 3 points
    I was with Alex in his first judo championship... My champion. [emoji16]
  2. 2 points
    Took me a couple years to track one down in my size, but it's sure worth the wait.
  3. 2 points
    I also don't think Fang really understands what is going to happen now. I'm going to track down a Shangri-la jr. amp no matter the cost just to rip it apart.
  4. 1 point
    Pat Metheny Group, Imaginary Day.
  5. 1 point
    Pub Fish & Chips (Joanne for scale) Then later after a nice country walk
  6. 1 point
    Test Tone @ Home live right now: http://mixlr.com/illuminator/chat
  7. 1 point
    Joanne is having Lamb ... I'm having Steak & Chip's Then Sticky Toffee Pudding Not all which made it to it's intended recipient
  8. 1 point
    Tubelab SE This is what I built. Since 45's run on a lower bias current, an output tranny for a 45 amp is cheaper than a 300b tranny, so while the iron wasn't cheap, it wasn't as much as I thought it would be. I bought the low imd version, which adds a bit to the cost. He wound quickly too, my iron was delivered to my house a week after I paid for it. Its their DHT board. Does take some research and figuring stuff out, because it supports different tubes you need to pick a tube, and then pick the iron and some other parts based on your tube. EDIT: He's revising the TSE to replace obsolete parts and make some other tweaks, I don't think the new board is available yet but it should be out pretty soon. BTW, one other "problem" I had. When I was swapping rectifier tubes soon after I got it running, I accidentally hit the switch to use the 300 ohm secondary. When I listened to my he500's like this, amp would distort when playing louder passages in a song. I thought somehow I had broken something, until I figured out the switch was in the wrong position. All good when I switched it back. I running it at a relatively low bias, around 25 ma. If I upped the bias, should put out more power before it distorts, but I don't need the power as long as the switch is in the right position lol. Randy
  9. 1 point
  10. 1 point
    Thought I would share a pic of my current project as an introduction, since this is my 2nd post here. The board is from Tubelab, its his Single Ended board, so this is a TSE amp. For you purists, it uses sand for a current source, they are under the board so you can't see it in the pics. Big tubes are 45's, driving Electraprint output iron which were wound for headphones, [email protected] with 46 and 300 ohm secondaries Edcor power tx, 5V4 rectifier into a CLC filter for B+ of 300V, and for now, a fairly simple DC reg for the DHT heater power. Working on its chassis now, a wooden box made from curly maple. The TSE pcb will be under a fiberglass plate that is all drilled out and ready. I have a few other coupling caps I will try out, see what I like the best. I also have a Coleman DHT filament heater that I am planning to use to drive the heaters in the 45's. I'll also have a wiki page at some point soon, with more details on what's inside and how it was built. Randy
  11. 1 point
    I took these two fellows.. …on a ride to big brother who has his own original Kevin DIY T2 PSU (reduced voltages - everything else as original). With this PSU both mini T2 are silent - no annoying hum. Here they are all together.
  12. 1 point
  13. 1 point
    That stuff is just too funny. So let's start at the beginning, 1k in series with the output is better than nothing (Cavalli, Woo, Kingsound etc.) but it should be around 5K. How 1K is similar to 5K and offer the same protection is beyond me. Does anybody at Hifiman understand Ohm's law? There are indeed two 2M resistors on that board. When I initially wrote that I had only looked at the amp board and was still trying to untangle the mess of this build. Still that should be 4.7M but 4M is close enough. Also, while the amp is very reminiscent of the SRA-10S... it does have the opamp input. You know what amp is based off the SRA-10S and has an opamp inputstage? The SRM-001... aka the 1995 portable amp. Yup there are some similarities there as well. So the output stage uses FQPF4N90C's as can be seen here: ...and the datasheet is here: http://www.mouser.com/ds/2/149/FQPF4N90C-195517.pdf Go down into Dynamic characteristics and there we have output capacitance, typical 65pf. So the headphones are roughly 130pf or so and you have two of these per driver. Yup, stellar job of keeping the Cob low. For reference, the 2SC4686A used in the KGSS and KGSSHV, 2.2pf. So the output capacitance here is just about 30 times higher. Same goes for what Stax have used for years. Also, notice the black cans on the source pins, those are inductors for some reason. Inductance and capacitive loads don't really mix, just look at the train wreck that is the Woo WES. For any laymen reading this, many know about the 10 times rule when matching sources to amps. The goal there is for the input impedance of the amp to be at least 10 times higher than the output impedance of the source. Same goes for preamps into poweramps etc. Same thing applies here, how do you think the amp likes driving the capacitance of the headphones when it first has to overcome its own output Cob? Bottom line, if anybody like JimL wants to take a look at the Jade2 amp, I'll send it to you for free. The only things I did to it was simplify the input wiring, as it makes no sense to go from the sockets to the amp PCB, then to the volume control, then back again. I also redid the earthing of the amp as it was very lacking for CE safety requirements. One more thing that amuses me endlessly with Hifiman is that familiar Chinese trait... victim hood. I still remember it well at Canjam 2010 when somebody gave Tyll a set of HE-5's (I think) to measure and Fang freaked out. It was his own personal set so he could do what ever he wanted with it but Fang did not approve. That speaks volumes about his character. I'm all for right being right but what about addressing the flat out lies in the specs, that a few parts were not properly soldered to the boards or that I'm sure the same crap applies to the 50K$ Shangri-La. They certainly use the same cable...
  14. 1 point
  15. 1 point
    Meanwhile, in Soviet Russia...
  16. 1 point
    Brisket Fairy came out and played a little. Cooked up some brisket, pork butt, and pineapple/cheddar/jalapeño sausage for our staff.
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