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Holy shitballs, that's like conspiracy theory level of mods! Ric Shultz at EVS does some pretty crazy things at times, but I will say I have always heard improvements with his work. But yeah, what the actual fuck was that modder thinking?!
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Calwen63 joined the community
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When modding goes off the rails...
kevin gilmore replied to spritzer's topic in Home Source Components
viva does the same shit wrapping various capacitors with wool of some kind. - Today
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This is something special as none of this actually does anything. Ferrites work at certain frequencies but the wire has to pass through it... not just have it vaguely in the same area. Lumps of aluminum tape and felt on the cables... yeah nothing at all. It seems like a bad DIY project but I have a sneaking suspicion that somebody is doing this as a service and charging a boatload for it.
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Megatron Electrostatic Headphone Amplifier
JoaMat replied to kevin gilmore's topic in Do It Yourself
Thanks a lot. I've been thinking of a 300K resistor cross the h11d to limit the upper grid voltage. -
When your audiophile OCD has OCD?
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Megatron Electrostatic Headphone Amplifier
kevin gilmore replied to kevin gilmore's topic in Do It Yourself
better put a 300v zener across the output of the h11d -
Someone had a massive snake oil OD... good god. Must be a vibration damping freak.
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I wasn't sure where to put this but this is a PS Audio Perfect Wave DAC so might as well be here. Found this thing dirt cheap in Japan, clearly modded and thought... why not. Might be fun... but boy ohh boy this is utter insanity. It was showed as up and running by the seller so I needed to go in and see how I could change the voltage on it. I didn't snap any pics of it when it arrived but here is one once the felt strips had been pulled off... yeah felt strips: That's the bottom so it was covered in these strips. Now I dug deeper: So there was this layer of aluminum tape that was painted and sealed on the edges with this rather coarse paint, almost like the stuff you'd use to make chalkboard finish. Then underneath there was come copper tape and the adhesive on this was nasty shit. I attacked it with IPA, acetone and adhesive cleaner (mineral spirit) and now it is mostly off the outside. I had to use plastic scrapers to get it off and machine polish the top over (due to all the small scratches from cleaning it) but it looks okey. Now I had yet to open it as the top cover is pushed up through the bottom and you need 4-40# screws to do that... something that is impossible to get here. Two weeks ago I found myself in Chicago on my annual visit and Kevin hooked me up with some that did the trick and here is what I found: Now one starts to wonder about sanity and what hose clamps have to do with audio quality but yeah... this is the most insane shit I've ever seen. This is the top cover and here is this paint the whole unit is covered in. No idea what it is but it is rather inert and I had to scrape it off the top and bottom panels. Seriously... hose clamps. This is so retarded it isn't even funny. A few things to note, see those felt strips, same as were on the outside of the unit and those ferrite beads and rods are all over it. Now to switch things up a bit, here is what looks like a brillo pad around the transformer. It's not steel wool and it was around it all. Here is another shot of the steel what ever and those rods glued to the bottom of the chassis. Also see the silver bits attached to the cables... yeah more on that later. Here it is with the cotton? pulled out of it showing what I've stepped into. How many hours did this take? Our lovely hose clamps again but look at that transformer. It is wound in aluminum tape, then the felt, then some rod, then more aluminum tape... Then those rods on the bottom of the chassis... I've started to peel stuff off and it is like an onion Main transformer and in the bottom right hand corner are all the cable ties holding those silver bits on the cables. Yeah, that is about 10 layers of aluminum plus some small ferrites and rods... Why? Fuck knows... Main transformer peeking through the madness as I need to get to it and read its markings to covert it to 230V. I'll have to do some more cleaning but this was just too good not to post...
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I really like this album. The song selection... the way she plays. I've listened to it twice in two days. Good morning coffee music. She got a new fan. ex.
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Another great one gone....RIP John Lodge. What a voice (EDIT: along with Justin)! https://www.the-independent.com/arts-entertainment/music/news/john-lodge-moody-blues-justin-hayward-b2843232.html
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Megatron Electrostatic Headphone Amplifier
JoaMat replied to kevin gilmore's topic in Do It Yourself
Schematics auto switching. Not sure it's accurate, but that's what I've done. New Grid Voltage Control boards. One trimmer for offset and the other for balance so, both sides are controlled simultaneously. Two jumpers. For 300B/2A3, EL34 and EML 20B-V4. Works al right, quite easy to use. The -510V is achieved with help from GRHV 110V supply. Here is one with Hammond 2VA trafo on board - 2.75in x 2in. New idea - servo controlled grid voltage. Okey, I've tried servo controlled Megatron (with solid state CCS) before and that failed... -
Thanks to @JoaMat for posting the 2A3/300B auto-switching filament supply. Although the picture isn’t very clear, I’ve been trying to figure out how it actually works. I roughly recreated the layout (still very preliminary, no routing yet. So please note it may/does contain errors. From what I can tell, the circuit likely uses the voltage comparator on the left to sense the voltage drop across a 0.05 Ω current-sense resistor, distinguishing the different filament currents of 2A3 vs. 300B. The two optocouplers at the upper right appear to be controlled by that comparator and might handle auto-bias adjustment. This is still an early interpretation. I’ll keep updating as I make progress or manage to get a cleaner schematic. That looks really interesting. Can I ask a quick question: Are the two trimmers on top each setting the grid voltage vs. plate current, or are they controlling the grid potential of each EL34 individually? Also, is the 120 V GRHV section meant to supply the bias/grid voltage reference for the output tubes?
- Yesterday
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The Knuckledragger 3rd Memorial Slow Forum Post
mikeymad replied to Knuckledragger's topic in Off Topic
- Last week
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the problem of "Agave Electrostatic Amplifier"
kevin gilmore replied to Omega_ELS's topic in Headphone Amplification
highly similar to hev70 sennheiser amp. and by that i mean n-channel fet as current source into another n-channel fet with grounded gate drive. sennheiser amp single high voltage + 600v. this amp +/-400v (initial guess on current way off) output device is infineon imw120r350m1 which has input capacitance of 3460pf. kind of high. there are better parts to use. like this one. C3M0900170D which has input capacitance of 202 pf. calculated output current is about 12.5ma and about 5 watts per heatsink. going to get fairly hot. mc33078 opamps perform very differently inverting and non-inverting. koss esp950 uses the same part in a very different way. much better ways of doing the unbalanced to balanced conversion. power supply about as basic and cheap as possible. the chinese will do this for less than $500. which means that this is infinitely better than the topping eha5. likely sounds better too. -
details -> scheme -> psu -> >Max output voltage: 280Vrms It doesn't seem like a very powerful thing. What do you think?
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The Knuckledragger 3rd Memorial Slow Forum Post
Knuckledragger replied to Knuckledragger's topic in Off Topic
Some damn, dirty hippie with entirely too many guitar amps. Taken in St. Petersburg, FL in 1973 by Joel Bernstein. -
I stumbled on this looking for something to listen to now that my queue is empty. I didn't know it existed. It's an interesting combo. All three of these musicians are obviously great. I enjoyed it but their styles didn't mesh all that great for me. ex.
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The Knuckledragger 3rd Memorial Slow Forum Post
Dusty Chalk replied to Knuckledragger's topic in Off Topic
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I recently thought about joining ICE...yes, really, but not what you think...not the evil ICE that we see everywhere, but HSI. https://www.ice.gov/about-ice/hsi The ones who investigate the real terrorist networks domestically. Mostly because I have had it with what the Russian plants did to get Trump elected and cement his position there, but also...because it would be easy. I get pinged all the time, recruitment pings on LinkedIn from obviously Russian organizations. One of them even had the audacity to communicate with me in Russian. I got as far as filling out The Questionnaire. There are a lot of questions of the "are you now or have you ever been" variety, but there are also questions that are much more to the point (see attached). I have zero problem killing bad guys. The above video is why. I do realize it's a lot easier knowing who the bad guys are in the above scenarios (they're shooting at you!), and that's kind of what I was imagining, but I do also realize that real life is not so clear cut. I had to bail (on working for ICE) for other reasons. (They wanted to be able to dictate whom I investigated and whom I didn't, being the biggest one.) But I remain staunchly pro-2A, and needed to renew my vow to myself to remain grounded and moral. There may not be people worse than Trump and Hegseth and Miller and the Heritage Foundation et al, but they wouldn't be so bad for life on this planet if it weren't for the extremist MAGA and Russians who are the real terrorists. And armed.
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Kalornard joined the community
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I made stroganoff the other day. I put too much black pepper in, but other than that, it was delicious. It was super spicy, and I wasn't even trying to make it so (the spiciest thing I put in there was black pepper, but I put my usual amount, which is about 1 cubic inch).
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RIP Ken Parker, designer of the most advanced guitar ever, the Parker Fly Deluxe. This one hits hard, I regret having to sell all my Parker Fly Deluxes over the course of the last year, they were the most amazing guitars. I just pulled the bass out of storage to fix and sell (it's just the battery compartment).
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The pressure gauge looks like one I used for fuel pressure on a 2009 Challenger I tracked for years. Love it! HS
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Not For Lack Of Trying by dodie (2025) https://open.qobuz.com/album/ukgy6v7yfn6tb Example: Second time through the album, and like it better than the first time. Released the same day as queen T above. This will have staying power in my queue.