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Agreed!

Have been having some offline discussions with JoaMat and Jose regarding the possibility of trimming the offset if desired. JoaMat came up with the idea of trimming the 100R resistors in series between the KSC2752 emitters and B-. He modeled it in a LT Spice model and I decided to give it a try. With my amp running at 14mA bias current, without this mod all the DC offset was between + 9VDC to + 4 VDC and balance was under 6VDC and I consider it totally fine. This exercise was more experimental and to satisfy the OCD part of me. I put a 50R resistor and 100R trimmer in series and adjust the sum to 90R based on JoMat's calculation. It can certainly be done with a single 150R trimmer, a fixed resistor in series with a trimmer is to protect against the small odd should a trimmer fails. I stopped making further adjustment once I got all the offset within 0.5VDC and balance within 0.2VDC. A few things to observe: 1. Turning one phase DC offset lower raises the offset in the opposite phase slightly. This gets a little tricky trying to zero out offset of both phases at the same time. 2. The bias current raises slightly as I adjust down the offset. In my case, the resulting increase in bias current was about 0.7mA. This matches what JoaMat saw in his LT Spice model. 3. The final resistance on all 4 "combo trimmers" fall between 86R - 90R. Take this as a reference only as this will vary from amp to amp and dependent on the bias current setting. I listened to the amp both before and after adjustment and frankly I could not detect a difference.

This thread has gone entirely too quiet. 3lb pork shoulder went in the smoker late last night. Hit 160 at 9 this morning and it's now wrapped/crutched and headed for 205. Looking forward to dinner.

Nah, don't mind at all, Al. Thanks Nate. If you go back to the very first post, you'll see why I gave it that name and the reservations that I had about it even then... little did I know that it would survive for so many years and become part of the fabric here. It's a great thread in the sense that it allows everyone to bring attention to notable individuals whose lives have been impactful in one way or another. But it was really meant for mostly for famous people who we don't have close personal connections to. Have to admit that it has creeped me out on more than one occasion for the very reason you mentioned, Al. Much better now. Reserve the right to call someone a fuck when they really were a fuck though... Charles Manson comes to mind in the not too distant past.

This weekend's Grand Prix junior event. For those of you who have never met Lance, he is the one dressed in white.

Different 121r and 1k trimmer in parallel. Ok, it's no nice but we haven't space on the PCB.

Now when there are nice tapping tools out there I think I try mount sands direct on heat sink. I've done this today. I cut of 20 mm of the board where the bracket should be so now it’s 80 mm x 160 mm. The layout was not meant for this so there is a need for a couple of extra jumper wires. Most things are doable. Here is my tapping tool with rather long shaft M3 tap.

How big of a dork am I that I put on my pre-moon in preparation for watching First Man? Mr. Armstrong presented me with my Eagle Scout badge; I'm very interested in seeing how the portrayal is, having actually met the man. I wish I had been able to see this in the theater, but at least I can watch it on large projection screen!

Thanks Nate. It seems more palatable. RIP Dick

I'm invoking executive privilege - changed.

Hey @Wmcmanus -- would you be opposed to changing the name of this thread to something softer like RIP Someone Or Other? Given that we use it for personal friends and family members, the original name is off-putting.

That movie was fucking amazing. I feel so glad that I got to meet the man.

@Hopstretch and @morphsci - the Google suggests that we should be watching Netflix's, Love Death and Robots.

It is watchable... Sorry...had to. HS

I did the real ID a few months ago at Corte Madera. Just show up early. It won't save you entirely from the line but in a world of shitty alternatives it is one of the least shitty ways to go.

So I've had the Massdrop version of the Koss ESP/95X sitting here for probably a month but not spent any time with them. I know I'm awful... That changed today so first some pics: Let's start with the any real change from the stock Koss version, the earpads: Now the stock pads are terrible but these are somehow worse. Cheap and nasty fabric covering the same nasty foam...yeah they went into the trash. Get some Vesper earpads but more on that later. As for the amp, well here are some internal pics: This is the same as the last unit I opened, stock 1990 amplifier board but the new PSU board. It's the same circuit, they just had to update it for new parts such as the new nasty volume control. Now for some impressions of the phones. The cable situation is the same as before, rather short cable and then they supply an extension to make up for it. As if anybody is ever going to use these as portables... So I ripped out the stock cable and fitted a wide PC-OCC Stax unit and angled Vesper earpads. I also removed the foam they have on the baffle as the Vesper pads come with some dust protection. Now this is more like it, here is the true king of budget headphones. Granted you have to spend the 500$ for the set and another 200$ for new cable and earpads but that's still the same as Monoprice is asking for their very mehhh set. The angled Vesper pads I got were a custom order and they really add something to the set. The imaging is improved and the slightly smaller cavity really helps them spring to life. They are a tiny bit top heavy now but that helps them really, makes them feel more alive. All in though, very much recommended and nice to see this 30 year old design still shine. One small caveat though, this set which is one of the first from Massdrop did ship with some dust inside the right driver so they are no noise free. One kinda expects that from the ESP950 though so it doesn't bother me too much.

Meanwhile, in Soviet Russia...

RIP to one of the Original Kings, Dick Dale....

r.i.p. Dick Dale...