Leaderboard

Here's the final board I just sent out to get manufactured... I added some more optional parts that help stabilize the current sense circuitry. The board is now 10mm x 58.4mm x 1mm. Parts are ordered, so it's a race to see if Mouser can ship my order before the boards arrive.

Building the world’s least efficient hardwood cutoff storage cabinet. Really needed the drawers above it so instead of doing the typical, proper, vertical cabinet, I went half-assed and threw all the sticks in a big drawer with sheets goods held behind the cabinet against the wall. Oh Yeah, the reason for the uneven overhang is I am going to mount the Wilton Woodworking vice on the one side and needed all the clearance. Oh Yeah Part Two, I also FINALLY got around to hanging the small French cleat panel I made way back. The craftsmanship in these holders in embarrassing.

In other news, I just got back the analog input board and assembled the amp. The sandwich is 6.2mm thick + bottom components for a total of about 9mm thick. Batteries are about 10mm on top of the input board. Back plate on and plugged into USB-C (charging LED on) Why we did this... Portable music Just analog from my phone at the moment. DAC is up next PS The Weight is 12oz or 340g

I used to call one of my cats Tawny Kitten when he was young....wife never understood why, I just explained it today. RIP Tawny....

Here is the simple adapter I made. Black wire connected to left and middle pins of the green holder and red wire to right pin. Black banana to E on the meter and red to C. At some point I must have changed C and E connectors on the meter to bananas but I can’t remember having done that… P.S. Found this in cyber space: https://jestineyong.com/duoyi-dy294-meter-repair/ https://www.pa4tim.nl/?p=6022

Adapter was the magic word. Made one with a 3-pin Dupont connector... very easy to swap the transistors. Thank you very much, champs! The 2cs3675 test somewhere between 1030-1120V on the DY294. Any special test procedures I should follow? Testing first with the Peak DCA75 checking pin's and type then the breakdown voltage with the DY294.

Some "old, beat up gear" given to a guy on /r/audiophile by his GF's dad.

Happy Belated Shelly, looks like it was pretty damned happy. 🙂

Thanks for all the birthday wishes! I had a great day building the Lego Roller Coaster set and had a fabulous dinner at a new favorite restaurant, MAD (for Madrid)! https://www.madhouston.com Everything was amazing!

Attempt #1 in gluing quartz to wood. Definitely should have worked with the handplane before attempting this glue up. Not sure how well it is going to work. Also hung up the clampseses.

This is how my first attempt to mill a pcb stencil turned out. The aluminum sheet comes from a Burgenfels beer can.

Switched from Megatron to the Blue Hawaii this morning. Different sound signature but equally as satisfying. This one is not the BJT version but the one that uses 2SK216/2SJ79 with cascoded CCS and adjustable plate current.

Any speculation on potential partners? I, for one, welcome our new Googleheiser overlords.

the opamp blows up at +/-40V would have to check the other parts, but +/-30V should absolutely work speaking of power... unbalanced/balanced/cast to balanced input block for all sorts of things, but mainly the uberamp, just need to find a way to get it into the box will probably involve splitting off the driver section. Uses GR power supply +/-30V for the front end and another GR power supply +/-40V to run the regulated output voltages to the output amp. If i add zeners to the servo amp, can easily go to +/-50V and as shown, its 100 watts of pure class A, and something north of 225 watts A/B front end NO feedback of any kind, .0025% thd at 20khz, 2nd harmonic. 3rd harmonic not measurable. output amps are current feedback. i think i have created a monster

First of all my mailman is awesome. This is what it looks like right now outside my apartment. All that snow on the deck is fresh, and it's going to continue for another 5 or 6 hours. The entire town has pretty much shut down (I didn't have to go the hospital, so I spent all day comparing headphones, what a life) yet I still get my package! This pair is bone stock, NOS. Overview My K340 says "electrostatic-dynamic systems" on the earcups. I'm not sure if they are bass heavy, bass light or the third one. What I do know is that they are a NOS pair that only has around 10 or so hours on them. I've been in contact with my seller the whole time who was really friendly and just today he told me he was the first owner, didn't use them much because he didn't like the way they sounded out of his receiver. Thus they've been in storage until he decided to sell them. I have not burned them in, I just had to listen to them as soon as they arrived. The headband is really plush, I don't see myself replacing it and the the elastics are pretty strong, not as strong as the ones in my K1000 or a K501 I used a lot, but they stay on my head really well. The cord on my pair is perfectly intact, no tangles so I was trying to be really gentle with it. It stretches out just over 6 feet, which is pretty short. Comfort is amazing. It's probably the most comfortable phone, ties with my (now sold) AudioTechnica A500 which just disappeared off your head after a few minutes. The only thing that puts the AT ahead is the K340 is really heavy. Thepleather pads (which are in perfect shape) are alright, but became uncomfortably hot and sticky after 4 hours of continuous use. Any sudden head movements doesn't move the headphones much unless I'm really trying. I still might replace the elastics for a slightly tighter fit. So far music I've played: Massive Attack - Mezzanine The Prodigy - Fat of the Land Mogwai - Mr Beast Sigur Ros - Takk A strange selection of music? Yup. I mostly got these for electronic music, which none of my other headphones really excelled at. The K1000 just can't do really low bass, and I prefer intimacy in electronic music. The HF-1 is too congested and small sounding. TheHD650 was what I turned to...it was acceptable but wasn't bringing me the last bit of nirvana. The Mogwai was thrown in since it has many dynamic passages going from really loud to quiet. All music was encoded from CD in lossless. Equipment: It's unfortunate but I have to use the headphone amp in the Lavry for the time being. However I feel that it has an excellent, discrete headphone amp that competes with most of the SS offerings that I've heard under $400. Also the DA10 has a ridiculous amount of overhead, putting out 7.75V at max volume (# 56). For my preferences I listen at soft to moderate volumes at all times and prefer to listen in a perfectly quiet environment. The HD650 will be the main headphone I'll be comparing it with, since they're both roughly in the same price bracket and like I mentioned before I want a notable phone for electronic music. For most of the music listed the HD650 was played between 12-20. The K340 between 20-28. The K340 is much harder to drive. I didn't have an SPL meter, but I feel I did an alright job in level matching. These are impressions from about 5 hours worth of listening: Mezzanine: First album I played was Mezzanine. Angel is a good track to test for bass extension, and volume. It was a little weird hearing this on the K340, it didn't sound exactly like how I wanted it to. The bass was absolutely amazing, went really deep and had great body and slam. But, there was something really weird about the rest of the percussion, the snare and cymbals sounded more distant and slightly muffled. Next came Risingson. Now this gave me goosebumps. All of the percussion just sounded perfect. When the guy started to sing it just sounded holographic with the background vocal stuff (dream on...), incredible my eyes went wide open. I played the track again 3 times Really the rest of Mezzanine was the same way. It was like hearing the album for the first time, the midrange was just amazing. Risingson, Teardrop, Man Next Door are my favorite tracks and this was the best I'd ever heard them. Most impressive about this headphone (that I gathered from this album) is the very textured deep bass, amidrange that gets out of the way (doesn't impart a house sound), 3D imaging, handles dynamic passages very well without the need to be cranked up to uncomfortable levels. Verdict: I listened to the album again on the HD650 and it didn't hold up well. The K340 clearly had it beat. The H650 midrange just wasn't cutting it, and it sounded 2-dimensional, which isn't doing justice for this album. Fat of the Land: Not as well recorded as Mezzanine. Not so many oohs and aahs here. Still I grew up on this album in high school, destroyed 2 CDs now on my third. This CD sounds good on the K340, but equally acceptable on the HD650. One thing I heard for the first time is the echoing off of the vocals on certain tracks that the HD650 wasn't doing, the Senn sounded more flat and dead for most of the vocals. Switched to K1000 to make sure this wasn't a result of the closed design and I heard those additional details I was hearing in the K340. Also on theHD 650 bass it hits hard, then disappears. A lot of the bass on this album is pretty distorted and is meant to fade in and out very quickly, the K340 was able to capture this attack/decay pattern more accurately. Still this album needs to be heard on a speaker system to really hear the bass effect. Verdict: K340 slightly edges out the HD650. I could live with either. Mr Beast: This album starts off slow then explodes into absolute madness (from Auto Rock to Glasgow Mega-Snake). I really loved this album with theHD 650, it has lots of bass, and is able to capture the magic of the piano. I'd usually listen to it on the K1000, simply because it was more dynamic, where theHD 650 made most of the album sound like every other generic post rock band (quiet, static, compressed). The K340 just rocked this album. Congested parts (Glasgow Mega-Snake) sounded congested and compressed. Dynamic songs (Friend of the Night) sounded dynamic and full of life. Plenty of body and warmth. Still the K340 lacked that absolute last level of high frequency extension that made cymbals sound a bit more artificial. TheHD650 made them sound more real. Verdict: aside from the last bit of high freq. extension the K340 lacked, I can say I enjoyed this album with the K340 just as much as the K1000. More in some parts that required the warm low bass andmidbass. Takk: Ah tough album. Very difficult to capture all the beauty and emotion in this one. If I had a world class speaker system I could just turn up, turn off the lights, this is how I'd like to experience it. But that's not happening in an apartment...so onto the headphones. I really love this album. I played it twice through on the K340, then once on theHD650. The K340 did it. The midrange was able to capture every last drop of emotion from the vocals, background singers, and the rest of the electronic parts. After hearing this the K340midrange is definitely more upfront compared to the HD650. The HD650 sounded dark, and sucked out a lot of the magic in this album. Verdict: I'd keep the K340 if only to listen to Sigur Ros, over and over, and over again Conclusion: On the headstage - it's very intimate. Not very wide or tall, but very deep. Imaging is superb, sounds meld together and seperate effortlessly creating a 3D image, I haven't heard this in any other headphone save for the Qualia, HE90, K1000 and the Omega 2 (I have not spent much time with the R10). If I had to compare my K340 to any headphone I'd say it sounds closest to the Omega 2. Prominent, textured bass, stunning midrange, 3-D imaging, intimate headstage, with a high end that is slightly rolled off in the extremes. Next up I plan on playing a lot of classical and jazz. Of recent I've been obsessed with the Star Wars soundtracks so I'm looking forward to seeing how they fare. I have another pair of K340 on its way (maybe tomorrow?) so I'm interested to see how if it sounds different or the same. All in all great day, god bless snow.

K340 second pair arrived: Good thing for Fridays, and nice staff I just picked up my second pair of K340 from Fedex. This pair is not NOS. Looks: This pair says "electrostatic-dynamic systems" on the earcups. Also the headband has the AKG logo on the top, the first pair doesn't, but both have stock headbands. The coiled cord has a few tangles. The headband and earpads are in excellent condition. The elastics on this pair definitely need to be replaced, the fit is really loose. Sound: I've only had them for an hour so far and I've only played Massive Attack's Mezzanine to really get a feel for the bass and midrange. This is really strange but this pair actually requires more power to drive properly! At 30 on my Lavry Black, the NOS pair is louder than this second pair. I switched multiple times during the same track to make sure it wasn't placebo. This might have something to do with the looser fit, but to get it to the same volume as the NOS pair I have to turn it up to about 33/34. Damn these headphones are hard to drive! At those levels it would be uncomfortably loud with the HD650, and the Grado HF-1 is always used under 10. So far I think that these may be the bass light version and my NOS pair either the bass heavy or the neutral (if such a third variation does exist, I tried to do my homework and came across an interesting thread showing the insides of the various versions). The midrange once again is very pleasing to the ears. I can't make any comments just yet about treble extension, but it sounds very similar to the NOS, if anything this pair is ever so slightly a bit brighter (noticeable in fast switching). Onto the bass: definitely do not dig as deep as the NOS pair. Briefly tried with my bass sweeps and it rolls off around 35 Hz. Below 30 Hz it's silent. On the NOS pair I get excellent tone at 20 Hz. Aside from the extension the overall bass volume is also less. Playing back all of Mezzanine the bass isn't as fleshed out as the NOS. It's still there and very enjoyable, had I never heard the NOS I wouldn't have found any fault in this pair. Volume wise if this comparison can be made the NOS pair's bass is like the HD650, the second pair more like the HD580/600. From a non-audiophile point of view: I had my friend come by to pick up some books, but he likes the Sneaker Pimps and Portishead more than Massive Attack (stone him!) I let him try on both sets, and he just sat there listening without saying anything. Finally he said something like "woah that sounded good, where can I get these?" (this is with the NOS) He switched back and forth a few times, and to him the only thing he noticed was the first pair had more bass, and didn't move around as much.

Oh no! Whitesnake video queen... Teenage crush. Godspeed, Tawny... HS