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Missed Al's post. If you want to do typing, get the 12" Macbook. Super light and small with a real keyboard plus fast enough for anything I need to do on the road! I use it all the time at work and in coffee shops and never need anything faster. The keyboard takes time getting used to but I actually prefer it now. Ordered a new iMac 27", 4.2GHz quad-core Intel Core i7, 32GB RAM, Radeon Pro 580 with 8GB of VRAM, and 512GB SSD (for those times when I need something a bit faster than the Macbook). Also, got the new ipad pro in the mail today. Excited to open it up.

Never mind the wiring rats' nest for now, it's making music! The problem I was having with one channel, worked out to be a cold solder joint on the global NFB resistor network on one tube. Was distorting the voltage (off by 10V) on its pzta56/lsk389 half and throwing the balance and offset WAY off. Once found and corrected, both channels are stable as a rock (while running 30 minutes) without the servo engaged. Under 1 volt balance and offset both channels. First listened with my SR-207 then my SR-009 (with a lousy iPhone 6 Plus as source). Using 2000 vintage SED Winged C EL34s at 20mA. Damn, this amp kicks major ass! Now time to mount the transformers, clean up the wiring and build the umbilical, wire up the bi-color power switch, replace the 12V zeners with 18V ones, get the RK50 somehow mounted in to the case, and button it all up. Will post glamour shots when done. Thank you Kevin for such an incredible 'stat amp. I'm really going to love this over my KGST.

A little change on the new iPad that I appreciate: they've moved the logic board on the smaller iPad Pro from the right side of the device to the center. The area surrounding the logic board gets quite warm under load, so its really nice that its moved from where you'd place your hands to a spot on the iPad that you don't touch as often. Hard to know whether this was done on purpose or if its just a serindipitous coincidence, but it is a welcome change. Before (9.7" model): After (10.5" model):

Thanks! A work in progress. A few questions first to start the troubleshooting on your GG. I'm only an ape with a DVM so will outline a methodology. What are your basic power on measurements: HV+/HV-, LV+/LV-, heaters? All LEDs on? Have you set your adjustments? What do they measureme: CCS/balance/offset? Where in the circuit is your amp going crazy when signal is applied? Help us understand what is "crazy". On one amp board or both PCBs? If one channel is good, use that as a standard to look for differences in the other. On one half of one LSK389 or both transistors on package? Is the symptom only at the headphone output? What are the LSK389 b,c,e voltages? Your issue might not be with the NFB. My amp's balance was so skewed that I was burning the same 50k resistor as Whitigir. Needless to say the same symptom had a different cause in my amp. The above info will be a good start at opening communication for help with evaluating your GG problem. Should not be too hard to localize and correct. I bought all my case parts/metal work complete from Head-Case member joehpj. Really nice design and product, and a great guy to deal with. Here's a photo after first receiving and trial fitting the all case parts. Listened to YouTube videos (MP3 audio with digital volume control) over iPhone on the GG with SR-207 last night. That combo was ridiculously great sounding. More headspace, bass slam and pitch, treble, detail, ambience, and just sounding quite a bit more natural than my Yggy>KGST> SR-009. Probably, the SR-009 on the GG really needs the refinement of the Yggy as source to really shine.

I haven't seen Prometheus. I'll consider myself lucky.

I published a modification for the Stax SRM-T1/T1S/006 in AudioXpress July 2017, which is just out. The modification adds 5.1 kilohm output safety resistors and cascoded constant current output loads, which with their heatsink fits the space vacated by the plate resistors - see photo. Spritzer did something similar a few years ago with an SRM-007, adding constant current loads, but he also changed to 6S4A outputs. Unlike plate resistors, constant current loads burn up practically no signal current, so while the stock amp burns up 9.2 mA signal current in the plate and feedback resistors at its specified 300 VRMS maximum output, the modified amplifier only uses 2.8 mA driving the feedback resistors, leaving much more current available to drive the headphones. Since the output tubes are much less stressed, distortion is decreased and 2 dB of extra headroom gained. The modified amp circuit is very similar to a KGST or KGDT. This is no accident, as the KGST was designed to be “a Stax SRM-007t with no cost or retail considerations,” and the 007t is a higher power T1. The modification lacks the KGST’s regulated power supply, but larger power supply caps have been fitted. Since the amplifier is fully differential pure class A with current sources or loads at every stage, the current draw is pretty constant, minimizing power supply effects. The modified T1 can drive demanding headphones like the SR-007 Mk I, something that the stock design strains to do. The relatively flabby bass, somewhat dark tonality and soft treble are largely eliminated. Replacing all the old electrolytic power supply caps should also be done as routine maintenance. Parts cost for the modification is about $35, so total parts cost is around $100. With T1 amplifiers going for $400-$700, this is the best bang for the buck, a good starter project for someone wanting to get into electrostatic amp DIY without going to a full build.

^This. Except for the part about Marmite, of course.

Have to rec this again because it's just so damn good. Bleachers -- Gone Now

You are one lucky guy G man! Joanne is such a gem. I have admired her from afar (and you're welcome to tell her so).

Joanne said she can replicate this at home (other than The Ivy part) Can confirm. $5.99 https://www.worldmarket.com/product/marmite.do locally https://stores.worldmarket.com/ca/greenbrae/2040-redwood-highway.html

To put it another way, compared to the Stax Mafia, this is like Stax juvenile delinquency.

Crumpets with Marmite butter at the Ivy. One thing I will miss!

I'll be 69 in less than a month....... and I never feel my age. I may feel younger or older at different times, but I'm glad i still feel my pulse......

Correct.

Ooops

Congratulation! Yeah this amp is awesome

Oh yes. Good lord, 120hz on a tablet feels do damn good. This thing is a monster.

fun with double talk

Resto-mod.

Cool!

I have the sweet home recommended duxtop and do not use my coil stove at all. Yuge upgrade.

Under all the hollandaise, there are Dungeness Crab and Avocado Benedicts And cornbread

Been listening to these on Spotify, and so far I've listened to the top 10 tracks by each band in the first row and enjoyed every one.

Lollers

Super Duper Burger, for Brian, *sigh*

Braised short rib sandwich