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Showing content with the highest reputation on 02/03/2023 in all areas

  1. Shouldn't we move on to predicting the seasons with capybaras? #stillnaptime
    2 points
  2. This week I was browsing the net and I came across this: http://bbs.erji.net/forum.php?mod=viewthread&tid=2239622 Now it is all in Chinese but these were the first pictures of the insides of the Woo Audio 3ES. This was an amp I never really paid any attention to, I'm so fedup with Woo and their sub-par crap, but finding internal pics does warrant a look. First off the pics aren't great but at least there are some schematics there and we need to try to verify they are correct. We have no further info than this as I can't find any more internal pics, so this is what know at this point. First the PSU: Now, nothing new here, same old crap Woo have been building for years but why place the output sockets right next to the power transformers like that? I mean the whole idea behind a two box solution is to place the noisy power transformer away from the amplifier and thus the output, not run the signal back into the PSU and have the output sockets right next to the, rather large, radiation field of the EI power transformers. Makes no sense but things are about to take a turn to the worse: Now... here is where things start to look a bit off and I'm going to see if anybody can spot it without venturing further. Now neither Kevin nor I can read Chinese so the markings on these two schematics that were included meant nothing to us: We focused on the tube schematic and wondered how this could work, I mean it is a simple grounded cathode 6SN7 input with a 300B cathode follower output. We are not dealing with a lot of gain here so at first the schematic had to be wrong, no way to drive electrostatics from this. Then Kevin figured it out, this is just a preamp, the latter schematic is the output for the headphones and what is that... it's a fucking Apex PA97 opamp!!! https://eu.mouser.com/datasheet/2/156/pa97u-1853045.pdf Go on, double check the pinout against the datasheet and look at the recommended values. Now look at the internal picture again and follow the wires, input selector is on the left and the preamp/headphone selector is on the right with the red wires. What's there next to the back panel with 4 identical modules and a shit ton of hotglue? The electrostatic module... which is made up for 4 of these which cost around 100$ each in bulk. This is a 14k$ amp! Now we don't know what is on the heatsinks next to the tubes, has to be a TO220 size part but no way to see what it is. The rest of the schematics make sense though. B+ goes directly onto the 300B plates and there is a grid resistor next to the "G" pin with the cap from the 6SN7's right next to it. Two large resistors next to each filament pin too. Then we have the large, brown, resistors going off the B+ to feed the 6SN7's and two identical plate resistors for it too. . Now what is the problem... well I can't see anywhere on the Woo site which says this is a hybrid amp, they talk about the 6SN7's, 300B's and the rectifier but nothing about a basic opamp outputs for the electrostatic outputs. Let's just quote them: "The new 3ES achieves the most ambitious dream in the audio world". Yeah... not so sure about that... Funny enough, clones of the Stax D10 are surfacing in China now and I have one. Guess what that one uses? Apex opamps.... and I bought one for 250$ shipped to me and it fits in the palm of my hand. Below are the rest of the pics from that Erji post for posterity.
    1 point
  3. https://www.autosport.com/f1/news/ford-confirms-formula-1-return-for-2026/10427644/ yay...
    1 point
  4. Big meteorology doesn't want you to know! Edit: Indeed! https://www.theguardian.com/world/2023/feb/02/quebec-canada-dead-groundhog-spring-undetermined
    1 point
  5. Punxsatawney Phil recommends you buy Natural Gas Futures! (Actually, we all know President Brandon fixes the price of Natural gas....)
    1 point
  6. Unrelated -- me: two new discoveries. First is big band-ish small ensemble, Mats-Up. Also, Pinhas & Sons -- Israeli nine-piece: Both of these are absolutely ace.
    1 point
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