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Voted. Just once, despite presidential advice to the contrary.

Fair warning: This is going be an absolutely (film) nerdy post and probably of zero interest to anyone but myself. With that said... For years my friend Brent (listeners of my radio show will know him as bludvesel) has given me shit about the incredibly boring names I use for my computers: 2012MacMini, 2011MacBook, 2015MacBookPro etc. I do this so I always know what I'm looking at on my network. My Wintendo has the imaginative name "Monolith" because it has a huge black case by Fractal Design. Now I have two Macs of the same model and year. With that in mind, I spent several hours renaming all of my Macs. Brent uses musicians that he likes for his machine names. For me that'd be an impossible task, picking which ones. Instead I went with film directors 2012 Mac Mini Quad Core i7: Kubrick, named after Stanley obviously. 2012 Mac Mini Dual Core i7: Fellini, named after Frederico. I considered Antonioni, but I found it too hard to spell. 2010 Mac Mini Core 2 Duo: Ulmer, named after the cult director. Fitting as he was a full generation older. My ailing 2015 Macintop isn't current renamed because it will mess up some dependencies in Traktor (or more to the point, data Traktor uses.) Eventually it will become Bergman.

Ahem, hard surface porn.

Meanwhile ... https://www.macrumors.com/2020/11/02/apple-november-event/ "Third event in 3 months, Apple. There better be some Arm-powered Macs this time Just One More Thing, eh?" https://www.theregister.com/2020/11/03/apple_announces_next_event_which/

One source I used. Great to deal with. https://www.ebay.com/itm/PTFE-wire-Alpha-5854-7-or-equiv-20-ga-Mil-16878-4-silver-plated-10-feet/292416116301 Many other wire gauges, solid or stranded available by seller. Do a search of his other items.

I spend way too much time on r/formuladank

Here are some photos of a recent Bespoke unit we delivered -

I have always wanted to hear Bob's Silver Seven T amps, powering his Amazing Loudspeakers.

Atmos 7.1 rig running on tube amps(!)

I am not especially fond of red headphones, but I find these really stunning. Excellent job.

Hmm so you have resumed taking in Bespoke orders, good news, Aumkar ✌️

I finished my first SRX+ build yesterday. It is overall quite satisfying. It doesn't have the breathtaking bass or unforgiving resolution of KGSSHV Carbon, but is rather non-fatiguing for long-term listening. I took the SRX+ Gerber file Kevin created (Thanks, Kevin!), added larger footprints in order to use the cheaper tube sockets, TO-92 footprints for the DN2540s and moved the heater-lift resistor dividers to the amp board so the wiring between this and the PSU board can be more streamlined. I also changed the small tubes to use 6.3V heater in order to match the surplus power transformer. The PSU board from Kevin follows JimL's original shunt PSU schematic. I added a normal bias tap in the zener diode string with a copied low pass filter, different lead spacing support on the output film caps in case a certain part number is out of stock. It is also cut short 1/2" from the original. Got too aggressive in fitting these boards into the small chassis. The internal space is barely large enough for the two boards to lay side-by-side. Had to mill off internal supports here and there, and ended up not having enough space for a real volume pot (the place holder is a rotary encoder waiting for a future attenuator board. The build started with a faint hum. Swapping tubes can reduce it to a certain level. Then I found a 55mVp-p saw-tooth ripple on the power, which is not supposed to be there (the shunt PSU has >120dB ripple rejection at power line frequency according to simulation). It turns out, the bias circuit voltage doubler drops its leg on the virtual ground and injects >1mA of ripple current, because the bias has to be ground-referenced. The virtual ground is not really a low-impedance node (about 60 ohm @ 60Hz with two 22uF caps). Any noise on the virtual ground is considered common mode to the shunt regulator, and is pretty much out of the control loop. Besides, with transformer HV voltage suitable for this design (I used 600V center-tapped), the voltage doubler doesn't have enough juice such that the 10M90 bottoms out at the low voltage points. So I modified the bias circuit to have its return tied to the output B+ and let the shunt regulator deal with the ripple current. Pro-bias is still easy to obtain, but the normal bias would have to come from dividing the B+ like in the original SRX circuit. The final assembly has 2.5mV hum in one channel and 5mV in the other. I don't think I can reduce them significantly beyond that without using DC heater and take care of the common mode noise from the header windings, perhaps also need to shield the small tubes. There is always some coupling from the heater to the cathode and it varies from tube to tube. With multiple tubes sharing the same AC heater I don't think you can balance it out completely using a pot, either. This simple amp performs well, THD+N is as low as 0.01% between 35dBV and 45dBV (40dBV being the rated operating voltage for the SR Lambda Pros to output 100dBSPL, which is pretty loud). One thing I'm not too happy about is the -2dB drop @ 20kHz when loaded with the AP (200k ohm + 66pf including cables). So I played a little with the open-loop performance. The driver stage has only -1.4dB drop @ 20kHz when disconnected from the final tubes, but the Miller cap of the 6SN7 is killing the high output impedance common-grid driver stage, dropping it to -9.5dB @ 20kHz. Negative feedback helped but didn't bring it back to ruler flat. It might help with a cathode follower stage before the 6SN7 but then there goes the simplicity. A rolled-off top end could explain the more forgiving sound, though. Thanks again to Kevin and Jim to make this such a fun project. If you are going to build it, I'd suggest using Jim's Revised shunt power supply for SRX Plus or any other dual voltage regulators. And don't use a chassis too small!

They are crossed over at 120Hz, which has a wavelength of 2.9 metres. which completely ignores the structure (because it is so much smaller than the wavelength of the sound; the structure is acoustically small).

Christian McBride Big Band - For Jimmy, Wes and Oliver Available on many streaming providers Old school damn fun big band jazz. Joey DeFrancesco on B3, Mark Whitfield on guitar.

I bought a pair of Kaldas RR1 cups/drivers/pads from the previous owner about 2 months ago. They squealed, Aumkar had generously replaced the headphones for him - and didn't require shipping back the original bespoke hardware. These were among the first RR1 produced. I've been totally stir crazy due to the lockdown. Though the most I'd played with electrostats was removing rotted foam from a set of lambdas, I figured this might be a fun project to tear down, and if I'm lucky restore. I modded an old Hifiman headband, and bought a cable from Mjolnir audio. I immediately heard the electric squeal, but it would periodically go away. I had a full 2 hour stretch of silence where I realized these were awesome headphones. Though I was biased towards my Koss ESP95X - after a head to head listening session, I had to admit I liked the Kaldas more for everything but treble. Unfortunately, the squeal and/or buzzing from the left earcup grew to become practically continuous. So I used Joamat's instructions to investigate and completely disassemble the left earcup. They were fairly easy to disassemble, except for one bolt that sits right behind the mini XLR connection. The mini XLR pins being so small, and me being TERRIBLE at soldering - I tried to avoid undoing the solder joint, but broke one of the wires. If you do this, be careful to undo the wired connections last, there are tiny M2 nuts that will fall out if you're not careful. After that, I found basically the same issue that Joamat found, the Bias wire was broken, and there were strands inside the female thread of the housing. It's possible that one strand got into the driver and caused the whine and buzzing. I liked the bolted assembly, and wanted to keep the headphones easy to disassemble, so I soldered in M2 terminal connections as shown. I had to use longer heat shrink tubing because I had wiring exposed at the mini XLR connection. I used a grinder on a dremel tool to make a larger hole in the cover - I found when I assembled initially, that I caused a short and lost volume out of the left earcup. To fix it - I ended up resoldering two of the wires at the mini XLR connection. Then I blew compressed air across the driver and stators, being careful to expose the driver for the most minimal time possible. Then I reassembled as shown including the two dust covers. Eager to test my work, I reassembled the headphones and connected to my Stax SRM 717. The left earcup was completely silent - success! Funny thing - the right earcup started squealing even louder! So I repeated the process of soldering terminal connections. When I reassembled, the right earcup still squealed. I was super frustrated, but went back and did the step I skipped, I blew compressed air across driver and stators. And that seems to have solved the final issue. I've now listened for about 10 hours with almost complete silence. To be honest there's been a handful of times, totaling maybe 30 seconds where I heard a slight buzzing, and thought "Oh no! Not again!" But shifting the earcup slightly cleared it immediately. My ears touch the dust covers, so I suspect it's a different issue entirely. Perhaps with a shift, my ear presses against the stator. The final picture is of my Frankenstein Kaldas RR1 conquests. I contacted Aumkar, not for help - but to suggest a few manufacturing improvements based on my findings. Aumkar was very kind, suggested that I solder directly to the bolts - and then informed me that he'd already incorporated all of the manufacturing improvements I suggested. So if you order a Kaldas RR1 conquest now - it will be more robust than the initial versions. Overall - I think this is a great product, and Aumkar has been a pleasure to chat with. If you're willing to buy an energizer separately, these sound better than the Koss, and far better than the L300/L500 I used to own. I hope Kaldas will produce a sequel. I like these headphones so much I'm having Vesper Audio quote out slightly thicker pads so my ears don't touch - and I ordered touch up paint to fix a couple spots I scratched or gouged during my project.

I had a very scary halloween last night ...and not in a good way. Background: I am mostly blind in one eye. I see very little out of my left one. I was born this way. Had the doctors caught it in time, they could have corrected it. I'd have had to wear an eye patch for several years (arr!) but I'd have gained sight in my bad eye. None of that happened. Last night I lit a candle I got a while ago. It's got 3 wicks and sits in a (rather flimsy) glass jar. The three wicks are a PITA, necessitating turning the candle to get them all lit. I was working on the third when one of the wicks shot off a bit of ash or hot wax and hit me in the face ...right below my good eye. I said "oh shit!" and put down the candle. After insuring I was alright. I looked at the candle. I didn't get hit by wax or ash. The jar shattered and I got hit in the face with a glass shard, a few mm below my one good eye. Ulp.