MLA

While at it, would it be possible to test some terminal blocks as well? I've tried to figure out what the UI tests for those 300-400V ratings actually mean. I don't get it fully, but DC seems less of a problem than AC in those tests...

Not a dumb question. Apart from being bigger and having solder lugs rather than pins (which makes it a whole lot easier to mount unless you have a board for it), the 4CP-2511 has exactly the same electrical and mechanical properties as 4CP-601, at least according to TKD's data sheets. I'm not aware of any serious shootouts between the two soundwise (A/B testing style), if others have please then please chime in? I've only used 4CP-601s and am very happy with those (the ones I've gotten track well and have excellent rotation feel) but of course the much higher price must include some magic to make it worthwhile. Only one way to find out...

Steep learning curve here Now I think I've unprotected all the right things.

Thanks for letting me know; turns out I had set the sharing features wrong. Now it should be editable. I've added your 5 to the table.

GB INTEREST SPREADSHEET: state your interest for pots and boards in the spreadsheet below (and if you find errors, please let me know). https://docs.google.com/spreadsheets/d/1O_LNaSDBViihkC0dNcYe46SqjOwteiTFmRmuXMRY4fA/edit?usp=sharing The POTs section of this GB is now officially closed. Entries for pot boards (type and quantity) can still be updated and edited.

So, quotations for the 4CP-2511 10K are in, and the cost will be 105 USD per piece plus shipping from Sweden to wherever you live. No price break below 500+ units, sorry TKD can of course do 50K or 100K versions of both the 601 and 25XX, but min qty is 5 pieces for any particular configuration. I've cloned a "wants it" spreadsheet from sorenb's masterful original and populated it with interests already expressed in this thread (see link in next post). I will leave it open for a few days for people to add/change things before asking for payment and placing the order. I've also put in a column with interest for pot boards. There is no quotation for these yet, but I figured it makes sense to have the interest check for those in the same place.

Yes, depending on final interest (they don't do smaller qtys than 5 of any item for this type of direct purchase). I haven't received the quotation foe those yet, but don't expect a price break unless the GB reaches 500+ units...

Thanks for the heads-up! My previous ones were all good, but if we go this route, I'll definitely test all of them before shipping them onwards. Seems you've gotten bad product a couple of times now (Toroidy, TKD). Is this just random bad luck, or are quality checks not in place at these companies?

So, I received a quotation from TKD this morning, and it seems the pricing of 3200 JPY per piece (what I've paid before) still stands. In addition there will be shipping and customs fees for entry to Sweden, so in total, this makes a GB price about 42-43 USD per piece + shipping to wherever you live. Price breaks can be had for orders of 500+ units, so not an option here An important factor is that production lead time is quite long: 45-60 days after payment. In other words, don't plan to use these in any immediate builds...

Interesting, I paid 3200 JPY a piece in April this year, plus another 2900 for the shipping. 10K would be my preference.

For those new to the thread: there is enough interest, so a GB will take place. State you interest in the GB INTEREST SPREADSHEET (link below) https://docs.google.com/spreadsheets/d/1O_LNaSDBViihkC0dNcYe46SqjOwteiTFmRmuXMRY4fA/edit?usp=sharing The POTs section of this GB is now officially closed. Entries for pot boards (type and quantity) can still be updated and edited.

Money sent. Thanks!

Well, I checked with the seller and he claims it's really opa445 for the servo, so I ordered a board and parts-kit. We'll see what turns up

Plainly, yes

It's been a few months since so I don't remember with certainty. I think I did, but only after replacing a bunch of other parts first (cree, 10m90s, stn9360...), so something else might well have killed them. Once I got it working, I was too happy to figure out the details of the problem

Extreme long shot; I went through the same part by part routine with one of my PSU boards where the regulation did not kick in, and in the end it turned out to be the KSC5026M:s. I had to replace both at the same time to make it work. Perhaps diode test those first?

Had it wrong, so deleted.

Cool! I'll put in my number tonight, seems I can't edit the spreadsheat via phone on the road... Done.

Quick check before ordering a new batch; anyone with a pair of GG boards to spare from the GB?

That's a SE-amp (very fun build by the way, I've built two of them) so I guess it has a twin somewhere waiting to be completed?

I can recommend 3Dhubs.com. Seems like quite a few people around the world have 3D printers that are idle most of the time, and thus are happy to print orders for others . If you have the drawing and upload it, chances are someone nearby can print it fairly cheaply. I have printed a bunch of STAX jacks, speaker waveguides, etc, this way. For STAX jacks, I found the below specification of dimensions from a previous KG post, and made the CAD file using tinkerCAD, which is a free online tool. It can't do complicated stuff, but for a cylinder with holes in, it works well enough... STAX jack Imagine the socket as a 6 pin with the 6th pin missing, but at position 0,0 (x,y) The rest of the pins are at 0,.2175 -.2175,0 +.2175,0 -.1087,-.1883 +.1087,-.1883

Sounds reasonable! I'll put in a couple of pots for the gain and see what I can find out...

So, I think I screwed up somewhere, but would like to ask advice before ripping things apart I built two of these with sligthly different gain settings. Both sound brilliant with HE500, but when trying out higher ohm cans on them (HD800, HD650), it's like the whole tone curve tilts a little bit, bass goes up, highs drop. It's the same effect on both amps, so my question is, did I systematically screw both up (created a filter effect somewhere due to erratic grounding perhaps?) or is this is to be expected for current drive of higher ohm cans?

Very cool, and very impressive layout work! Would love to build one if the opportunity arises.

Okay then...