MLA

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...

Or go surface mount if/where power handling requirements allow? I'm really impressed by the level of tininess and with GRLV singles, this would be a very compact amp.

Brilliant, thanks!

What would the current draw be for a balanced version? Inside or outside GRLV range ( think I saw 1,5 amps somewhere)?

As did I, and I thought I checked... Anyway, good that you caught it, and since you're very likely the first builder, please report if you run into any other issues...

There's a board for everything (almost)... http://sjostromaudio.com/pages/index.php/hifi-projects/109-dct02-the-dc-trap-high-end-style?showall=1&limitstart= http://sjostromaudio.net/shop/mains-circuits/11-dct02-dc-filter-for-toroidal-transformers.html

True, and my dac is actually quite well behaved, so no real reason However, I was going to expand my CFA2 to balanced anyway. A friend is building a Dynahi and I'm interested in comparing those two, and putting the input board in front will help test some single ended sources others have recommended.

Does sound like an interesting challenge to spot the difference! 10-15 dB should make a difference though. I'll get an input board from Sorens groupbuy and see what comes out of it...

if coming from a balanced source, is there an advantage to running it through the input board, rather than straight to a CFA2 quartet for balanced out?

I did have a pair left, so PM me your address and I'll ship them your way. 11 ptza06/56 sounds about right. Haven't seen a BOM around, but it's a very straightforward build with no superexotic parts. Square cap markings tend to be film, round electrolytic and oval MLCC. Then put RN60D in the Mouser search engine and select all values you need.

I think I have a spare pair of the SMD version (v9) at home, will check after work.

Boards arrived, all in great shape. Thanks!!!

Are those switchers of the ready made or home made variety? Thinking about trying this, but not sure what requirements to set on switchers in this use (max ripple, for example)?