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Saw Death of a Salesman, RSC Stratford on Avon, today; Athony Sher and Harriet Walter, actors of the highest calibre. Awesome. http://www.rsc.org.uk/whats-on/death-of-a-salesman/ And while I'm on the actor thing, daughter has just nailed a three month tour as Titania and Helena in Midsummer Night's Dream and also as Mary Bennet in Pride and Prejudice. http://www.chapterhouse.org/

And just out of the oven, banana chocolate chip muffins.

Well, I plan on getting the black sports one. I've become a bit addicted to activity trackers (wearing a vivosmart currently, which syncs with my garmin edge), and this seams to offer the best those have to offer plus a bit more. My only concerns are the battery life when using the features i like and how accurate the HR meter will be.

The PBS series "Twice Born" is pretty amazing. Sometimes tragic and sad but you can't help but wonder if everything is possible.

i'd be interested in a Florida bike meet

Indeed

Sous vide pork chops

Prepping for tomorrow - blueberry stuffed French toast.

We have a flatiron steak in the water bath at 128F. That will be seared off later on the grill and accompanied by some spinach with shallots and mushrooms.

Thanks for your comments, pongo5. Spritzer: Actually the 6SN7GTA/B is a pretty good tube for this amp. The RCA tube manual specs are: Max plate voltage: 450 volt Max peak plate voltage: 1500 volts NOTE!!! Max plate dissipation: 5 watts/plate, 7.5 watts both plates combined. Amplification factor: 20 Note that these tubes were used in a lot of early TVs for vertical oscillators and deflection oscillators, same kind of duty as 6S4A tubes were designed for. - hence the peak plate voltage rating. When I was debugging my SRX the tubes would sometimes be sitting there for a few minutes with 600+ volts from cathode to plate - no harm done. They tested exactly the same on a tube tester afterwards as before. By comparison: 6S4A Max plate voltage: 550 volt Max peak plate voltage: 2000 volts Max plate dissipation: 8.5 watts amplification factor: 16.5 ECC99: Max plate voltage: 400 volts Max peak plate voltage: none specified Max plate dissipation: 5 watts, dissipation for both plates combined not specified. Amplification factor: 22 EL34 Max plate voltage: 800 volts (Mullard specifies 600 volts when triode strapped) Max plate dissipation: 25 watts Amplification factor (triode strapped): 10.8 The 6SN7GTA/B is at least as good a tube as the ECC99 if not better. - higher plate voltage, equal power dissipation, specified peak plate voltage of 1500 volt which is more than it will ever see in the SRX circuit. Doesn't match the 6SA4 (great choice by KG) in power but it's not far off in voltage specs, I've found matching between tube sections to be excellent (generally less than 5-10 volts difference in circuit) and in the SRX I'm running it at about 4.5 watts total dissipation - 325 volts and 7 mA/plate. Doesn't sound like much, but with the cascoded current sources, driving the current loads to clipping requires less than 5 MICROamps, so 99.9% of the standing current is available to drive the headphones. This makes a major difference compared to using resistor loads (blechhh!) where the headphone (high impedance) is constantly fighting a losing battle versus the load resistor (low impedance by comparison) for the signal current. The EL34 used in the ESX variant has a lot more power, but because of its lower amplification factor when triode strapped, plus its higher Miller capacitance, the closed loop frequency response barely makes it out to 20 kHz before rolling off. And that's with current sources, if you use load resistors it starts to roll off earlier. With 6SN7GTA/B tubes due to the higher amplification factor and slightly less Miller capacitance, the open loop response rolls off above 11 kHz, and the measured closed loop frequency response is flat to 20 kHz and r-3 dB at 46 kHz - that's at 100 volts RMS output into a 100 pf dummy load. The 6S4A does very well here, slightly lower amplification factor but less Miller capacitance, the open loop response rolls off at about 20 kHz (calculated). The issue with frequency response occurs because the input stage is a cascode, which has the disadvantage, as a driver stage, of having a high output impedance. In combination with the Miller capacitance of the output stage, this results in the open loop response of the circuit rolling off at higher frequencies. For example, with the 6SN7GTA/B it is -3dB at approx 11-12 kHz. With the EL34 (I measured the grid to plate capacitance as about 10 pf it rolls off at about 8 kHz. With the ECC99 it rolls off around 9 kHz. The circuit doesn't have a lot of excess gain to begin with. With the 6SN7 there is about 14 dB feedback (5-fold) at lower frequencies, rolling off to no feedback at around 50 kHz. With the EL34 the feedback is around 8 dB (2.5-fold) at lower frequencies. If you do stupid stuff like Mikhail did with substituting tubes for the input section you may wind up with no feedback and the circuit running open loop. So if you're wondering whether I thought about tube choice a bit - yes, I did. If you use ECL82s with the pentodes strapped as triodes you need to see if the amplification factor is high enough and the Miller capacitance low enough to make a good combination. I've just resubmitted my article on this to AudioXpress - apparently they didn't get my previous submission - where I discuss this and other things in infinite gory detail.

A large part of it is the photography, as I went for low light in a fairly well lit room so the overall lume is degraded by the settings. It is fine, but not as good as many of my other watches. Fortunately, I do not give half a shit as I rarely need to know the time in the dark.

I keep forgetting to take a photo of the steak before it is consumed. As an alternative measurement of the night -

Colin went with a Chelsea queen