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Moving day! New furnitature looks amazing in the new place. Hat tip to @Hopstretch who sold me his family’s old dining room set. My old apartment was too small for a dining room table so I’ve been eating meals at home on the couch or at my desk for years. Now I get to eat at a table like an adult. Feels good, man!

Milo and I got the speaker boxes mostly complete today. Made some round holes and some rectangular panels. Tweeter holes are in the Cherry baffles only, as they're not deep enough to need holes in the MDF panel too. Woofer holes and port tube holes in back. Cherry baffles got milled and drilled as well. And the first coat of Arm-R-Seal. The fluting is strictly aesthetics.

Got out of the office.

I might need to fire my photographer, but here's something new.

Second day in Sydney, lovely city this is. We're very close to the Harbor....when we got here, we took a walk down to the harbor and looked through a nice local market at an area called the Rocks. Got some absolutely amazing licorice there, the maker is a fucking genius at bringing some of the most unexpected ingredients together to make a delicious treat. Then got a distant pic of the Opera House (we'll tour it later), but some big-ass thing was in the way. Today, we did a hop-on-hop-off tour of the city, stopped in a few places including Bondi Beach, Chinatown, several market areas, and then I walked back to the hotel while Karen is still shopping Lot of walking, but enjoying this a lot!

Mentally and physically exhausted after clearing out and cleaning my old apartment. There is definitely something about packing each and every one of your worldly possessions that gets the emotions going. You wonder things like "how the hell did I ever acquire so much shit?" and "how the hell did all this shit ever fit in that tiny apartment?", but it also gives and opportunity to reflect on how you got to where you are and on all the family, friends, enemies and acquaintances who have been a part of your journey along the way. In any case, time to crack the good tequila, get drunk, and sleep for at least 10-12 hours.

Not the greatest pics, but here is the router table Steve and I built, with the horizontal and mortising setups shown below

Did some fine tuning on my Megatron. Bring the regulated HV down to 430VDC rails and changed one resistor from 21K to 15K to supply 300VDC to the front end tubes. In my case the front end tubes draw about 8.5mA total. Also changes the EL34 tubes around in an attempt to bring down the output offset. It's now down to 12VDC yet not as low as I would like. Have a few more sets of EL34 to swap and match to see how low I can bring the offset down to. The output balance is around 3VDC for both channels. The toggle switch on the back of the PSU controls the power to the CPC1117N relay on the GRHV and function as the HV delay switch.

Stairs went in easy yesterday. Solid as a rock. Not sure these beams holding up our front porch had to be replaced, but we did it anyway.

I finally built my Blue Hawaii - a single box KG 2015 which uses the mosfets, (but I will build the BJT boards too). All GR supplies. I was inspired by a Triumph Rocket motorcycle for the chrome trim and I wanted volume indication in the dark so it has a circle of leds and a delayed pointer off the heater warm up. While I was working all this out Kevin published the Grounded Grid so I am building one of those in a similar case. Looking forward to some extended listening now. Thanks Kevin for a great design

Here's the HV version set to 450v. Have to test this one still.

l cooked Steak a la Stoneham at my dad's tonight. Horace Stoneham was the NY Giants owner who brought the team to SF 60 years ago. My oldest brother came over for dinner and we watched the game while having dinner. My dad took him to the second ever MLB game on the west coast 60 years ago this week. Stoneham got Alfred's Steakhouse -- still in operation -- to make this dish and they added it to their menu. My dad has been copying it ever since. It is strips of steak tossed with spices and flour and fried up with some parsley, green onions and sherry. I'll post the "recipe" if anyone wants it, but it is mostly ingredients and methods but no quantities. Tasty stuff that reminds me of my childhood.

It is a very good question, but he's used to fitting a lot into a small space. Or so he says. BTW, here's my role in the shop tonight: Lap Dog Lap

It stopped raining long enough to take a couple of pics of the beams we replaced. I'm especially psyched about the LVL that replaced a completely rotten beam perpendicular to the house. And now we've turned into an electronics shop with Dr. Luvdunhill building the crossovers for Otis's speakers.

I too got out of the office, and went back to school.

Um, yeah. I was so drunk last night that I spent half an hour trying to find the “Who’s Drunk” thread. Never did.

Done! These are not just your standard two ways. Instead, Marc has paired basically a full range driver and a super tweeter, then customized a crossover to take best advantage of that pairing. These drivers have to stretch their legs before I can really assess them, but so far I'm impressed. They're bigger than I had originally thought I'd build them, but still, make a pretty good nearfield monitor. Bass is far better than I expected. Eventually, they will darken to match the Parasound case. The window will speed that process up.

Wow Nate, what a coincidence!

Here's the accompanying board for the GR HV & LV supplies. It's got a built-in controller to turn the HV on after a delay (if needed) along with a power LED indicator (flashing to solid). I've also added a tap for both Normal and Pro bias.

Had lunch with Grawk at Champy's in Chattanooga Great time catching up before he went off to a bacon festival he didn't invite me to Sent from my ONEPLUS A3000 using Tapatalk

I was able to get the 450v supply up and running. I did have one error on the board. The current source feeding the 10v reference gets up to 150 degree F, but I can add more copper around it. I think it will be just fine. I was running this with a 110mA load.

Long day of mountain single track, followed by BHSE and drinks.

Got the micro up and running. This is set for 12v. Depending on the op amp this should support from 5v to about 20v. The larger should support from 12v to 50v. Noise looks good but I really need a screened room.

learn the art of the bottle lip. no glasses nor shirts required.

Tikka Masala beef ribs. I can recommend these.

Lemon oregano sous vide pork loin with cumin baked potato, creamed spinach and balsamic-grilled radicchio.

I had a pair of these... And a 50" Panny Plasma in a small class C motorhome. This will be a walk in the park. We got one crossover finished, will most likely finish the other Tuesday eve. I'll glue on the Cherry baffles tonight, then it's just a matter of soldering on a few spade lugs.

I acquired 10 boxes of my friends' record collection that I helped amass and listened to daily during high school. Picked a 12" Echo and the Bunnymen for sentimental value and then something else I haven't heard in years. Fun stuff.

Smoked Panko and herb crusted Rack of Lamb. Sent from my iPhone using Tapatalk

Mini and micro versions of the gr78xx supplies...

I have finished my GRLV "portable"

BLACK & BLUE Pan-seared filet mignon tips, tomatoes, Point Reyes blue cheese on romaine with blue cheese dressing & crispy fried onions HARVEST Bacon, mozzarella, dried champagne grapes & rosemary WARM PEAR TART Puff pastry baked with pears & cinnamon streusel, vanilla ice cream & caramel sauce

Hmmm, what might these become?

Alfresco brunch hot off the fire. 12 ‘o clock somewhere etc. etc.

Really does fit your room well. Hope the floor is sturdy, because that stuff is heavy! @TMoney threw in some very kind (and tasty) sweeteners and I immediately reinvested the entire proceeds in new audio gear, as is traditional.

Built this last weekend. Peopoly Moai SLA 3D printer kit. Build took about 4.5 hours, pretty straight forward and well thought out design. For those not familiar, SLA style 3d printers are quite different from regular FDM 3d printers. Where FDM melts and extrudes plastic layer by layer to build a model, SLA uses a light source to cure a UV sensitive plastic resin layer by layer. The resin sits in a small reservoir, a metal built plate presses down to the bottom, and the light source cures a given layer. The reservoir then peels itself off the cured resin, the metal plate dips back into the liquid resin one step higher, and the next layer is cured from the light below. Repeat over and over until your model is fulled 'pulled out' of the rub. The two typical methods of SLA printing are dubbed 'SLA' which uses a laser and galvanometers to trace each layers' design, and 'DLP' which uses a DLP or LED screen to project the stencil of an entire layer. Advantage of SLA type is that it's a bit more precise/detailed, advantage of 'DLP' type is that it's cheaper and can cure an entire layer at once so it can be faster for larger models. SLA resolution is limited to the size of the laser beam, DLP resolution is limited to the pixel size but is jagged in comparison. As LED screens improve in resolution and get cheaper, I expect DLP to become more popular in the future. SLA can be kinda messy, smelly, and is slower and considerably more costly than FDM 3d printing. The resins right now also aren't that great mechanically - they're pretty brittle. The advantage they have is that they're WAY more precise than FDM printers. For this reason, they're used a lot by the dental, jewelry, and miniatures industries. I already have an FDM printer that serves me well for rough prototyping, but this printer should be much more useful for creating production level short run molds. I've wanted this ability for a while now but these machines are typically $4-10k+ all in, so this kit for a fraction of the price (~$1300) is a great deal. Those interested in something similar but even cheaper (~$500) might want to check out the Wanhao D7 or Anycubic Photon, both DLP type machines, but you have to be willing to tweak things a bit more. Anyways, enough rambling. Onto some build pics! Kit came in a big ol' box. Very well packaged. Some of the electronics and the two galvanometers. The laser shoots into those two little mirrors, which direct the laser up to the build area and control the X and Y positions for tracing out each layer. All put together. Liquid resin stays in that clear vat, aluminum build plate dips into it from above to control Z position and holds the model. Gotta keep the door closed so UV light doesn't start curing the resin. In action! It looks really cool in person. One thing I love is how quiet it is during operation - no problems letting this run overnight. The laser is coming in from below. Post processing the final part. This is just a little test ring to make sure things are working to spec and the build went as planned. Agitate it in IPA for a while to get rid of any excess resin, agitate in water to rinse off. Repeat a few times and then put in the sun or under a UV light for a while to fully harden. I might get an ultrasonic cleaner later for this step since I'm inpatient. Haven't printed anything terribly exciting yet, mainly just small calibration models to get dimensional accuracy locked in. I'll post something more interesting later.

Sous vide pork chops.

Today's project... 50" X 19" Birch butcher block, stained Gray. This will be the top of my new A/V rack, which is your typical wire shelving, but epoxy coated Black.

I don't normally read in this thread or he wouldn't have lasted that long, sorry Al

The Copenhagen is a differential cascode circuit. The Copenhagen V uses tubes (valves) for the upper device, while the Copenhagen S uses transistors (sand). They are otherwise just about the same. It does indeed use input and output transformers (amorphous Lundahls in both cases, though the inputs can use mu metal instead). The tubes (E81L's) need not be matched at all. It is what is often called a "transconductance amp". In essence, it uses the headphone's impedance as an I/V converter, and it takes advantage of the slight Sennheiser impedance bump to make it a bit more euphonic. When used with Senns, I'd describe the sound as happy and punchy (kind of making them sound like how Grados would sound if they were not grating) - some people hate it, others love it, but it definitely has a sound. It can be linearized with the addition of some parallel resistance on the output (this is what a triode amp does except the parallel load is the tube plate impedance). Without doing that, it is not great with the Focals. Even with, they are so poorly damped that it would not be my first choice for powering them. With phones that have a flat impedance, it is pretty neutral. It's not an amp for everyone (definitely not for the objectivist crowd), but it is my favorite these days - I use a Copenhagen S with 650's for most pleasure listening.

Speaker boxes now clad in Black laminate, because we had enough left over from the router table project... Making a solid Cherry 3/4" thick baffle to glue on top of MDF baffles...

Refurbished my Ruger 10/22 Ruger BX Trigger, extended magazine release, skeletonized charging handle, Tactical Solutions threaded and fluted bull barrel, Hogue overmolded rubber thumbhole stock, picatinny optic mount, Nikon Prostaff Rimfire 3-9x BDC scope. I think it came out pretty nice. I should have taken a before picture.

First time wearing this since it came back from service.

I excited to get new electrostatic headphones from Soviet Union. Than you for your newsletter.

Lacking brisket, I grilled a tri-tip instead. It’s more CA anyway. Went OK.

Reduced voltage on my “modified” T2. DHT by night.

We did end up buying the hand made, foam and latex free bed. It was over the top, but, after daily back pain for years, to suddenly realize my back has not hurt since the day we got it has made the price worth it.

Dinner is served

I’ve two PSUs for my electrostatic amplifiers. The DIY T2 has 500 volts rails so I’m feeding all my amplifiers with 500 volts. Now I’ve been thinking of building a new PSU with 400 volts. From what I understand the only reason to go higher then 400 volts is if you really want high sound levels. Today I’ve brought down the T2 PSU to +/- 400 V and -460 V (the -560 V in my PSU is produced by its own regulator connected to ground). The only modification on T2 amplifier needed was to change the battery voltage from 740 V to 640 V – swapped the 4.7K resistors to 6.8K. Since I use offset servos similar to the opto servo Kevin introduced in his designs a couple of years ago I didn’t have to change anything else.