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last batch came out nice -- more pickling.

Top Ten Most Beautiful Cameras of All Time

I just put a new cable on my second set (beause reasons) and I do like them a lot. I also ripped apart one set to examine the drivers and a lot of effort went into these. Bunch of custom molded parts though the stators themselves are PCB.

Neat list. He missed the Contura. I got to play with one of these for a bit.

We call them Homer cars now because of one episode of The Simpsons, in which Homer designs a car... and hilarity ensues.

HEDD-ADAM ATM we are beyond thrilled to announce HEDDphone® - the first full-range headphone design based on HEDD / ADAM founder and speaker veteran Klaus Heinz’ world-known Air Motion Transformer driver!! The Air Motion Transformer (AMT) is an electrodynamic transducer that allows to move air significantly faster than common voice coil, magnetostatic (planar) or electrostatic systems. Their traditional piston-like movement is overcome by a folded diaphragm that squeezes out air four times faster: A breakthrough for capturing more details in any audio recording. In order to reproduce the complete audible frequency band (and beyond), HEDDphone® introduces VVT® technology (pat. pending), a new variable diaphragm geometry that replaces the fixed geometric structure of conventional AMT tweeters. Aiming at both, the audiophile and professional markets, the HEDDphone® brings the enormous dynamic capabilities and the superior sonic resolution of the AMT principle to the world of top-end headphones. It excels where it really matters: in accurate, untamed, and touching music reproduction. We will show the first handmade units at this week's MUNICH HIGH END SHOW, May 9–12. Meet us in Hall 4 / P03, take listen, and help us spread the word on this unique new Made in Germany headphone design. HEDDphone ONE will be available in Q3 2019. The price will be well below 2000€.

Have an awesome day!

THANKS ALL.... I managed to have 3 days of events/parties and now we are holed up hiding from the virus. At least SeedLady got to plant new flowers, and harvest a huge Collard Greens.....which tonight I attempt to cook.

Been following this one closely. Right now there are reports of the headband lacking enough extension for us coneheads so I'm waiting for them to update it, which they said they would. There also have been some reviews of them with preliminary measurements, worth a look though as always, well salted. The question, of course, is do I actually need them, and are they any better than what I have already.

The nearfield monitors are getting pretty good reviews. I was a big fan of AMT Heil speakers so I'd be interested to hear them.

I had s Chance to hear these At the last CanJam in NYC. I think they have potential and I’m looking forward to hearing them in a private setting.

Genesis P-Orridge.

Ahhhh one of those 50s bubble cars inspired by the space age... Cadillac Cyclone 1959:

I’m not a real big fan of giant racks of gear in front of my screen...

Nelson Pass, along with running his very successful company, supports the DIY community with some landmark minimalist designs. This is not one of them. https://www.passdiy.com/project/speakers/the-kleinhorn-part-1

She’s amazing! Did you listen to that version of Dream On she sung with Post Modern Jukebox? I ❤️

I have a new love, sorry Dolly Parton.

Al Di Meola - Across The Universe

Happy Birthday to my favorite person!!!

Happy birthday Bonnie! Cheers

Prince Street Girls How Susan Meiselas’s home neighborhood produced one of her most influential bodies of work – a study of adolescence, femininity and the gentrification of New York

The first place I saw this circuit was in an electrostatic amp design by Joe Curcio using 6DJ8 tubes, which was published in the very first issue of Glass Audio (Vol 1, no. 0), 1988. That's where I found the reference to the Birt article. I had to go to the MIT library to find a copy of the article on microfilm. I have it in a pdf file so if you PM me, I can send you a copy. Here is a quote from the article (part II): "From a discussion of the general principles in last month's article, the requirements for the first stage of a practical amplifier are now fairly clear. We have seen that for good balance and low push-push [as opposed to push-pull] gain, [tubes] V1 and V2 should have a high gm and large anode impedance...... A better plan is to substitute cascode stages for V1 and V2. It is generally possible to achieve a higher gain in this way, and a screen grid supply is not required. The grids of the upper triodes of the cascode pair require ideally to be at a constant potential relative to cathode. This is not a difficult problem, as we may decouple the grids to cathode, and make the grid feed resistor large. Alternatively, a cross coupling arrangement can be used as shown in figure 9 [this is the cross coupling the SRX uses]. The operation of this circuit is relatively interesting. When a push-pull signal is applied, it can be seen that the drive to the upper triodes of the cascode pair is applied to both the grid and cathode, in anti phase. As far as the cathode circuit is concerned, this turns out to be equivalent to doubling the gm of the upper valve, and therefore the cathode impedance is halved and the voltage gain to this point is halved. However, the grid-to-cathode voltage of each upper triode is the same as it would be in a conventional cascode amplifier, and the overall gain is similar." My comments and clarifications are in [ ]. The article then goes on to plot the V-I characteristics of the cross-coupled circuit using 12AX7 tubes, which, surprise, look just like a standard cascode, i.e. pentode-like. You may not like to call this a cascode because it doesn't keep the grid of the upper tube constant, but considering that cascode was originally coined as a contraction of CASCaded triODE, that the connections of the two tubes are the same as a standard cascode (plate of lower tube to cathode of upper tube), the same current runs through both tubes, and that the V-I curves of this circuit are the same as a standard cascode circuit, I don't know what else you could call it. Just don't let those two extra lines confuse you. Note that the SRX input circuit is NOT an LTP into a common cathode because of the connection between the PLATE of the lower triode to the CATHODE of the upper triode ON THE SAME SIDE. The common-cathode-like connection of the PLATE of the lower triode to the GRID of the upper triode is on THE OPPOSITE SIDE. This is the cross-connection. Take it out, substitute a fixed voltage to the grid of the upper triodes and you have the Hedge circuit, which is a cascode differential pair (balanced) or cascode LTP (single ended). Given that the gain of the cross-coupled circuit is the same as the standard cascode, I calculated the gain as about 41-42 dB, and an output impedance per side of close to 147 kilohm, using the estimated rp and gain for the low current used in the SRX circuit. That's with my 250 kilohm plate resistors rather than the original 300k. If you use the standard published 12AT7 parameters, you'll get a slightly different answer. The input capacitance of the input circuit is low because of the cascode connection. The issue is the high output impedance of the input stage into the output tube Miller capacitance. With the 6SN7GTA/B, the Miller capacitance is about 84 pf, and the circuit rolls off above 11-12 kHz. There is about 14 dB feedback at low frequencies, and so the calculated closed loop gain rolls off above about 53 kHz, which is what I measured. "