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I somehow managed to copy H and C from HeadCase logo and mill it on the plate. picture in B/W

This is not directly related to the original topic, but ...the tiny Windows box I bought from BozosPenisRocketFund.com arrived today and I don't feel like making a general bitching about Winders thread. So this is my first experience with Windows 10. It's been updating off and on for two hours now. By Gaben's Grizzled Grin, this is why we pay The Mac Tax. For all of the questionable decisions and bizarre choices that Tim Apple makes, I cannot for the life of me understand how people use Windows as their primary OS. If I didn't have Mac hardware, I'd probably grow out a neckbeard and attempt to learn some flavor of linux.

A picnic in Sonoma Square

Picked up a gift certificate at a local spa for my wife for Mother's Day. I wanted to give the monetary equivalent of three 50-minute massages ($87 each). The person getting the GC for me asked her co-worker what 3 times the price was, and before she could even pull out the calculator, I told her the amount. They both stared at me in awe, the second one double-checked my "work" and proclaimed I was right. they spent the next few minutes completing the card, and talking about how good I was with math. Scary.... They certainly LOOKED lovely.... 😂

Alternatively

For any fans of The Wire (or just great television), the limited series We Own This City (HBO) by Justin Fenton, George Pelecanos, and yep, David Simon, has a really strong pilot. Second episode hits in a couple days.

Kevin can confirm but I am pretty sure you'll be fine - the current draw is very minimal like a few 10mA IIRC. Unless you are dropping some unusually high voltage through the GRLV there is not much heat to dissipate for the MJW21193/21194.

Mahler can test the attention span. https://slippedisc.com/2022/04/yannick-stops-mahler-twice-for-phone-flash-and-snoring/

Ladies & Gentlemen - The Rolling Stones Live album from the Exile Tour. I still think Mick Taylor was the best lead guitar player they've ever had.

I blame Colin for everything, especially Brent.

Have made a few test inscriptions on aluminum with CNC machine.

Short Ribs Fried Chicken I Blame Colin.

These Elac's are making me smile They may be small but they're kinda HUNG (while also sporting some big juicy bass balls). Zero buyer's remorse here.

Is this just a blinged-out Grado? 🤔

Coquille St. Jacques Six-Onion Soup Lamb Chops with goat-cheese grits and a mushroom,apple and baby kale medley with Crème Brûlée for dessert

Thanks for joining Head-Case. I'm glad you're here. That said, you should be aware that this isn't your typical internet forum. We're not here so that you'll have another place to sell your stuff. We're not looking for people trying to pad their post counts, or demonstrate their ability to find witty things on the internet. If you've come here looking for advice on which headphones to buy, perhaps you should check out http://www.innerfidelity.com. Tyll Hertsens, founder of Head-Room and long time community giant is the proprietor there, and does everything he can to ensure that accurate information is disseminated about headphones at every level. This is predominantly a place for friends to discuss music, audio gear, and whatever else tickles our fancy. We are sometimes quite rude, often irreverant, and regularly abusive. Think of it like the corner bar where everyone knows each other. Don't mistake our familiarity with each other as familiarity with you, even if you've seen our names in other locations before. Spend some time reading before you start to post. Get familiar with what is going on, and who the various people are. Don't just jump right into the fray. This is your only warning, but I hope you can participate. There's a lot of good information, and more importantly, good people here.

looks like this needs to be bumped occassionally

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.

@JimLFor starters, thank you very much for sharing. Have since found your article as well, so i'd consider me in a good place to start. And given my non-existing skillset, this is where you may all laugh heartily Am a recent Stax convert in search of a amp. Have had a lot to weigh in and eventually had it down to one out of three; i) a used T1 with your mod, ii) a used 727 -unmodded for starters- (no offense to the usual two suspects), iii) a used 353X/XBK with only a heatsink replacement, largest i could fit. Given availability, pricing and most of all condition-to-price, i 'settled' on buying a used T1 but.. i'm no longer sure buying a battered 5-hands down piece of equipment that's seen, what? Thirty years of usage? for 600ish is wise. Given my limited budget that is (it's not only the initial cost, it's also the longevity i need take in consideration). Since the newer T1 version diagram is also available -is that even legal? Tell me not-, i've decided i will start from scratch; draw the PCB with your modifications incorprated, print it and slowly go from there. Which really adds to it all in some ways, doesn't it ^^ Opinions/ideas as to the.. soundness of my (final, revision 2.0) approach are more than welcome. * And speaking of ideas, ( @kevin gilmoresince i'm tagging you anyway, not sure if i've ever thanked you before, so, sincere thanks for making so much of your work available. Leaves options for folks like me that we wouldn't ever have had otherwise. Much obliged sir) Was wondering if the above's progressed any further? And if so, would you be willing to share?

Out of Stax brand amps, I've used the 313, 007t, and 717, and preferred the 717 by a good margin. Considering the similarities between that and the KGSS, the suggestion is a very good one, if you can swing it. The L700 does tend to be a touch bright though and you may need a bit of EQ to get the highs to behave. It's not bad however, I don't use more than 4db anywhere. JimL's suggestion is the most cost effective solution for a good amp by far. I would say that they're not too amp picky and even very basic amps sound decent... as long as they're good amps.

For an inexpensive alternative, you could get an old SRM-T1, then for around $100, replace all the old electrolytic capacitors and put in my CCS mod. For another $100 substitute a TKD pot for the Alps, although you lose the balance function. Won't sound as good as the KG alternatives, but will sound better than any standard Stax amp IMHO.

Well, you can do the same mods on the newer SRM-006, and similar mods on an SRM-007 using 7.5 mA constant current loads.

Having a T1S sitting idle here I decided to have some fun with it. Drew up a small CCS board, a scrap heatsink and voila...an improved amp is born. Bias supply fixed, all caps replaced and output resistors fitted. I ran it a bit hotter than stock so I had to modify the tail resistor on the output cathodes down to 1.5K but that is easy.

work in progress hangs off the side with thin angle bracket, no drilling of holes

The cap on the bias supply output is a big no-no these days so a 4M7 resistor after that is what I've usually done. Good that you added the 5K1 resistors though. You are right that this isn't for us so adding a small switcher to power the front end would be overkill. One other "wrinkle" to consider are the first and second generation T1's. Yours is the much more common second (which Stax called "new T1") but I've never had one of the earlier ones. The circuitry seems to be a bit different but I'm not sure what they changed.

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

Good work JimL - don't mind the comment from the janitor

You're right about the LV supply (Stax did stick in some zener diodes to sort of regulate it), but this was meant to be a simple mod. It is intended to be bang for buck, and the most significant improvement is the constant current mod. Yes the power supply could be much better, but the constant current mod is a first order improvement, the power supply is a second order improvement. The intended audience wasn't the Stax Mafia, it was people who have a Stax amp and want to improve it without going to the expense of a KGST level amp. Or are just getting into Stax and are willing to do a little DIY (or have it done for them). I think more people would be interested in Stax if they could buy a $500 used amp, put $100 and a few hours work into it for some significant improvements, instead of spending a few thousand for the amp. Not everyone is interested in building from scratch. Actually, I didn't comment on the bias supply as I was not aware that was an issue, but now that I look at the schematic, I see that there should be a 5 megohm resistor after the last capacitor for protection. Damn!

Most of the parts in the T1's can be found but yeah, anybody with any sense would never mod these for other people. The PCB's aren't of good quality and easy enough to damage something beyond repair. For us it is just fun to muck around with this stuff... I for one find it to be cathartic to fix some of the older stuff even if it can try to kill you from time to time. Looks at the naughty SRA-3S in the corner...

so much can go wrong when you are working on something 20+ years old. So many obsolete parts... The people that know what they are doing probably won't touch stuff they do not own, and people willing to modify your stuff probably are the people you don't want touching it.