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  1. Built a Megatron. Seems to be the perfect amp to build during the seemingly unending shortage of 10m90s. I used up my final few pieces of 10m90s and C2M1000170D for this simple build, and it gave me some mild anxiety and regret for not hoarding up those sands. However, the build experience and result are worth it. Build process and after thoughts I started off with a pair of generic chassis from Taobao. 32cm wide, 8cm tall, 35cm deep. Silver and black anodised aluminium. They weren't available in other finishes but this looks clean enough to me. They do have some minor scratches and dents if you look hard enough though. The casework was done by a laser etching service provider I found on Taobao. The end result was a clean and modern appearance. Inside the PSU are a pair of +/-450V GRHV, +/- 15V GRLV, delay board and a 270VA toroidal transformer. The idea was to create a PSU that can be used by both the Megatron and the Grounded Grid amp units. These components fit the chassis nicely with little room for a third GRHV board for the 300v rail for Megatron. Outputs are split into AC and DC outputs. Transformer specs: The heatsinks for the amp unit were probably redundant since most of the heat comes off from the top. The amp board could probably fit into a smaller and lighter chassis, but I chose the same chassis as the PSU just so that they can stack. The amp build was straight forward and relatively easy compared to a Carbon build or any of the KG dynamic amp builds, due to the low component count. I did not use any boutique components in this build. The coupling caps are Wima, and the voltage rail decoupling caps are Siemens. Volume pot is an EIZZ-style stepped attenuator, internal signal wirings are pure copper. Special care was taken when routing the heater filament wires to avoid hum. Amp testing and adjustment was simple. Just ensure the all the rails are as spec'ed and that's about it. The voltage offset settles automatically after power on. No need to fiddle with any potentiometer when the amp is powered on, so it is much safer to test than the Carbon or the T2 family. Sound I used the Megatron with ES-1A, and here is my impression of the Megatron after comparing it with GG (on the same PSU), Carbon (450V GRHV 15V GRLV) and Mini T2 (triple GRHV). Currently I am using the Megatron with a quad of Mullard XF2 and PSVane EL34PH. The front end tubes are all Valvos. The sound of the Megatron is warm, slightly thick in the mids, and non fatiguing and airy in the treble. It sounds very natural and the imaging is holographic with good recordings. While it is very detailed, it does not ruin joy if the recordings are of poorer quality. Older or poorly mixed recordings have a smooth timbre and organic vibe when heard from the Megatron. While the Megatron's treble is not as extended as the Carbon's, it complements the overall signature to create a very complete soundstage and convincing sense of separation and space. What makes the Megatron standout from crowd lies in its low end - it is an amp for bassheads. It has by far the most THICC bass compared to my other amps, even more than the Carbon. The bass extends as deep as the Carbon, but the Megatron has a nice lift in the mid bass that makes my ES 1a slam extra hard. Listening to EDMs and fast pop tracks on E-Stats is finally satisfying, and I can finally stash away my planars. Carbon is like an antithesis to the Megatron. Carbon is like a clean cutting razor with little tolerance for inaccuracies where as Megatron adds a lot of joy and flavour into the listening experience. Carbon also sounds a little linear. Although the stage is wide, it is not as deep as the Megatron's. GG sounds more organic than Carbon in general. The GG's signature is quite dependent on the tubes. With the XF2s, GG is warm and clean, but doesn't deviate far from the Carbon sound. The bass isn't as tight and fast, and treble could sound stiff and slightly shrill with the wrong tubes - such as the re-issue Mullard EL34. Mini T2 sounds slightly leaner and cleaner than the Megatron, and has a much smaller bass. It is as enjoyable a listening experience for me, but the Mini T2 was much harder to build - by sheer component count. Tube placement and choices Placing the EL34s in this manner shown below allows one to use two matched quads of EL34 if matched octets are unavailable. Initially I used cheap Linlai tubes for the front end and had issues with sound imbalance and hum - turned out that the tubes were the culprits. Switched to some cheap NOS and the issues were gone. So my advice would be to use well built tubes from reputable makers. The 12AU7s affect the sound significantly. The option to roll tubes makes Megatron extra fun to use. More photos of the internals and the back of the amp coming up soon, when I am more free. I would say that the Megatron is my favourite amp - until I build the T2.
    14 points
  2. Another way to build floating shelves, without purchasing the steel supports.
    14 points
  3. Attained the ability to leave the country (and re-enter legally) Now awaiting communication from 'M' with details of "Your next mission, Mr. Bond"
    14 points
  4. 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
    13 points
  5. Working on party favors for a little headphone/craft beer nerd get together this weekend. Took forever to cut the 3D rendering of the logo but all done and used the new keyhole bit to cut keyholes for mounting on the back. Putting sealer on tonight so I can finish with boat varnish tomorrow. Then just add the bottle openers and done.
    13 points
  6. I did sous vide picanha for the first time today. A simple rub of spices, smoked salt and olive oil, then cooked in the bath at 133F for 6 hours. The 'grill' part comes from very briefly finishing on the pellet grill, just one minutes a side, with the flame box open and the temp at the absolute highest I could get it, about 700F! Served with fresh chimichurri, I was in meat heaven.
    13 points
  7. Homework! The interview I had earlier this week gave me homework, so that's a good sign.
    11 points
  8. Got my new little Mac Studio for work
    11 points
  9. RIP Choco Taco(s) https://thetakeout.com/choco-taco-discontinued-1849327038 https://www.npr.org/2022/07/26/1113692240/choco-taco-discontinued-ice-cream https://www.washingtonpost.com/food/2022/07/26/choco-tacos-klondike-discontinued/ https://www.washingtonpost.com/food/2022/07/26/choco-taco-appreciation-nostalgia/ The Choco Taco saved me in my hour of need, when, while undergoing a grueling wait outside the temple of encased meats, the now defunct Hot Dougs, some kindly gents took pity on us, and provided sustenance for us, in the form of the aforementioned Choco Taco(s). They were well received. Choco Taco, We Salute You! You will be missed.
    11 points
  10. You know how I feel about pussy.
    11 points
  11. Picked this up yesterday. I blame Andy @blubliss. 😜
    10 points
  12. This is what the thread is about. Detroit Style Pizza! With a BIG pepperoni. 🤩
    10 points
  13. Great news, at least for the fencing crowd and our family. The US men' and women's teams medaled, silver...even without Lance's help. The French women's Olympian whom Lance used to train with and bested a few times, took gold. She was coached by her fiancé who used to train at the club as well. While training in So Cal they used to come over for my BBQ and Booker Syrah. I truly believe that is what led to their results and medals.
    10 points
  14. 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!
    9 points
  15. Went to one of my local dealers today, got to listen to the LX-60's as well as the LSX II's. The 60's are amazingly balanced top to bottom, very smooth yet detailed sounding; the bass is deep yet very tuneful I'd say. Yet at times I thought it was still a little too polite...maybe TOO refined..... The LSX II's were a little more bloomy in the mids; I actually heard more of the room & reverb on a couple recordings. It may not have been as flat as the LS-60's tonally, but it was not glaring, and it sounded quite nice. I think the LSX II's with the KC62 subwoofer (they have a line level output for subs I believe) would be an awesome pairing at about 1/2 the cost of the LS-60's. But damn do those 60's look nice!
    9 points
  16. The pentode experiment gets a little twist - with a beam tetrode. In my search for an acceptable output device, I went through the popular low-power transmitting tubes. The 807/6L6 family has such a wide, kinky curve in the low current region with typical Vg2 (250V) and was rejected as a candidate at the first glance. However, the curves around zero Vg1 looks quite linear. Lowering the Vg2 could sort of 'bring them down' to the low current region. With about 60V on the G2, the kinks are largely gone, and the linearity looks pretty good (pictured below X= 100V/div, Y= 5mA/div, Vg1= 0.5V/step). Another benefit is that Ig2 comes down considerably with such a low Vg2, which allows me to use the same simple G2 supply used with the GU-50 (zener diode paralleled with a 10uF cap). I compared quite a few tubes on the curve tracer. The National Union 807s (shown above) from WWII era seem to have the best linearity and are the most stable. The RCA and Sylvania tend to oscillate on my test jig. 1625s are about the same. Unfortunately I don't have enough National Union for a matched quad. The earlier 6L6/6L6-G are not officially rated for 400V plate voltage and have to be excluded. The Tung-sol 6L6WGB/5881 (the real deal, not the 'reissue') looks much more linear compared to the 6L6GC. The Sylvania 5881 (shown above) although has the same internal structure as the Tung-sol, doesn't seem to be as linear. The 1624 would be an interesting direct-heating variant that has a bit higher gain than the 807. The 2E26/2E24 brothers are suitable, too. Here are the 807s on the test bed: The result is convincing: The 100Vrms output FFT shows harmonics -115dB below the fundamental: The 1624 turned out to be a disaster. It was hard to get a clean, low capacitance filament supply. When attached to the signal path, the common-mode noise would kill the S/N and the capacitance would mess up the frequency response and THD. I have to admit I don't have much experience with direct-heating tubes in circuits where every uV counts. It would be nice if the few exotic direct-heating tube eStat amp owners can get their units measured and share their secret to success... The grounded-grid cascode output stage is such a nice thing that it allows us to play with many tube types, as long as they have enough plate voltage and power ratings and are reasonably linear. We could end up having unique amps that still have top-notch performance.
    9 points
  17. A delicious omen for the weekend...
    9 points
  18. I turned 20,000 days old today... (yes, really) ...and counting
    8 points
  19. Lamb kefta kabob lollipops with local squash and onions. Home made tzatziki not pictured.
    8 points
  20. Oh dear God! If I owned a Blackstone grill, I'd cook this for the entire neighborhood! Damn this is good!
    8 points
  21. Finished the new drill station, which meant I get to trash one of my earliest builds, back when I just got the Track Saw and had nothing else. Just need to add some kind of finish, cut out a power cable hole or two and put a cleat on it.
    8 points
  22. Got to see my favorite, Mark Burgess of the Chameleons, at a special tour he's doing. He does acoustic, and he has a guitarist doing the echo-y/reverb-y stuff for which the band is well known. REALLY interesting concept, and last night's venue was a little "Coffee Haus" above a Firehouse museum type place. All in Millis, MA, pretty much nowhere. The room was very nice and quite intimate. Took my son, we both loved it, and got to chat with Mark before and after. Lots of good chat about the songs and his history, stuff we had never heard before. Quite a great night. And I'm going to see him again Thursday night at another place.
    8 points
  23. Returned from a shopping trip to Paso Robles.
    8 points
  24. Swapped back to the AT cartridge and did some listening this evening!
    7 points
  25. Sometimes I think I'm the only one who understands what "retirement" means. Or maybe I'm just fucking lazy.
    7 points
  26. Visited Killington Vt and their tribute to the Beatles (or Charles Manson)
    7 points
  27. Have been listening to a bunch of Cocteau Twins and This Mortal Coil and highly recommend it.
    7 points
  28. >8 year bump. Allison and I were talking through this exact topic last night and i remembered this discussion from forever ago... pretty fun to go back and see where I was and where I am now. some things remain and some don't. I feel a lot more confident these days especially in honorable mentions as I've build up far more breadth and understanding of some genres, especially metal. Top 5: The Smashing Pumpkins - Siamese Dream. Still as complete as ever. Neko Case - Fox Confessor Brings the Flood. Still the best female vocals for me. Radiohead - In Rainbows. Over time I've realized that it's nice to just hear how amazing Radiohead can be and not have to think too much about it. Their most listenable album. Tool - Lateralus. Still the best metal and progressive blended together and polished beyond imagination. Sufjan Stevens - Carrie & Lowell. I go to a lot of different individual songs when I need to come to grips with death. This is the only full album though. Couldn't count the number of times I've cried while listening to this one. Honorables: The Dismemberment Plan - Emergency & I. Not sure why this wasn't on the old list. Not far off of Pumpkins in terms of an album I would want people to think of when they think of me. Converge - Jane Doe. I have absorbed so much heavy music in the last 3-5 years and amongst all of it, this is truly supreme for chaos. HUM - Inlet. I'm a child of the 90's and this is the closest anyone got in recent times to peak 90's rock. On permanent repeat. Tash Sultana - Flow State. The album that got me back into caring about headphones because I became obsessed with making this sound as good as possible. Legendary opener. Kaki King - Dreaming of Revenge. My favorite acoustic album with stellar intimate vocals as a big plus. Art Pepper + 11 - Modern Jazz Classics. Art had it all and this is 100% bangers. The Beatles - Revolver. Love arguing with Allison about why this is the best. Do Make Say Think - Stubborn Persistent Illusions. My favorite post rock. A perfect deep thinker. Tool - Aenima. Has closed the gap with Lateralus over the years. I find the two completely complimentary now. Wouldn't argue with anyone preferring this from the full cataloge. See ya'll in 2030.
    7 points
  29. Saw Jimmy Vivino and Ronnie Earl last week. Really nice Blues, all different types. We went because of Ronnie Earl, and the fact that Jimmy had grown up and went to school in the same hometown as my wife (Glen Rock, NJ); I wasn't familiar with him otherwise. Turned out to be a HELL of a show! Ronnie has a bunch of health issues, so it was great to see him live. And Jimmy was right up there in energy, voice, and spirit. he also had a boatload of great stories from clubs across the states and musicians from the 60's on....
    7 points
  30. RIP Claes 😢 This one is the one I saw the most near my offices in SF
    7 points
  31. Celebrating the Birthday of Corrinne Bedecarre.
    6 points
  32. 6 points
  33. I drove past this sight and had to turn around and take pics. Thickest and largest slabs I've ever seen in person. As I drove away, I saw the stump where this big boy came down.
    6 points
  34. Breakfast courtesy of the the city folks that came out to see us yesterday. Such wonderous things they have in the big city.
    6 points
  35. Ribeye, sautéed mushrooms & corn on the cob.
    6 points
  36. Please accept my apologies for any lowering of the signal to noise ratio in advance but my sincere and profound thanks (as a philistine of all things electronic) to people like Birgir, Kevin, Justin and the rest of you that have influenced (directly and indirectly) the creation of masterpieces such as the one below and the influence they have on the lives of us mere mortal lovers of music. This is the culmination of a dream of over 15 years in the making: Special thanks to Birgir for his efforts and support to this community at large
    6 points
  37. Okay it is only FB funny, but I still thought it was funny.
    6 points
  38. RIP Isabella - what a nice doggy. She had a great life from the pics. But it sure is tough to say goodbye to an animal companion. The difficult kind thing to do. And RIP Nichelle Nichols. Alas boldly gone.
    6 points
  39. Went to the Pacific Coast Air Museum with the Brits. Felt the need for speed. But I ain't no fortunate son. Heard some interesting tales from the docent present about how they acquired the various airframes, which are a fairly representative sample of American fighters in the Jet Age. The one with the most interesting story is AF77-102 The "First Responder" lead F-15 to arrive over NYC on 9/11. Interesting history.
    6 points
  40. BBC Music have finally put almost all the "Later with Jools Holland" archive on YouTube and oh boy I am like a kid in a candy store.
    6 points
  41. Buena Vista Social Club (25th Anniversary Edition) Buena Vista Social Club 1997 https://album.link/i/1569844173 Example: Warm day? not much fits the bill better than Cuban.
    6 points
  42. Another newborn CFA3 dual mono setup here. Thank you Mr. Gilmore and Audiostar and Mirko!
    6 points
  43. Sunday morning heart attack breakfast... Chili con queso & sausage omelet, fried potatoes and onion, biscuits (AKA Brent's Kryptonite) and iced coffee.
    6 points
  44. Our good friend, Lance's fencing coach and mentor just finished a world cup/world championship fencing competition in Cairo. As has been his record for many years, his fencers medaled! Now through the Paris Olympics he is co-coaching the Hong Kong team.
    6 points
  45. Depeche Mode – Violator Sounds better than the last time I listened to it...
    6 points
  46. 5 points
  47. Brent and I tried this escape room game out (on game pass). It is actually pretty fun! Though he makes some... I guess we can say 'interesting' choices in life, Brent's MENSA status has not been in question for me and he turns out to be a pretty decent partner for solving logic puzzles.
    5 points
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