Build Thread - A New Take on the Classic Pass Labs D1 with an ESS Dac

sorry only 1 extra is cut off. but thats ok, 0.01mv is enough for good measurements. there are a couple of rogues that seem a bit high from early on, that i might test again if i dont get any repeats. early in the piece i wasnt using the digital count down timer, just an egg timer and i found that if it was done too quick the gm was higher than it should be and settled fully after about 4 mins even though it appeared to have stopped after 3
 
Hey opc: hehe indeed, i'm also hoping those couple of really high measurements are legit and there is more. there is a bit of a trend there with a few larger ones, fingers crossed!! regardless it seems about as consistent as one would think and the expression seems pretty linear through the cct now i've got rid of the dc error, so i'm pretty happy with the final results so far.
 
guys, i need to call for interest again to confirm numbers for the fets. please pm me or email to confirm. i have done 90 now and will stop at 140 so by wednesday latest. i will send emails to those addresses that i have at hand easily saved in the group folder, but i know there were many more than this. thanks
 
hey hey, well i hear a few people's fets have arrived and more should be arriving every day. so where are the builders?

heres an old pic of my ackodac akd12p when it was mostly done, its been rearranged with a brand new usb board and some more suitable transformers will be here on monday.

but i'll post these pics just to get the ball rolling and to give a few ideas.

will post more during next week. at this point i still hadent figured where i was going to put the caps, was pretty crowded, thus moving to 2 box build and dual diff
 

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its a class D amp chassis from hexateq, they dont have them like this one anymore and they dont really list chassis on their site, i scored this used on the forum, but its not big enough without using an external psu, well not for my dac anyway hehe it says something when a power amp chassis isnt big enough for your dac.

one box of transformers arrived today which is cool, only had the aleph jx ones in there though, the other is close behind and has the dac and circlotron iron in there.
 
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hey hey, well i hear a few people's fets have arrived and more should be arriving every day. so where are the builders?

heres an old pic of my ackodac akd12p when it was mostly done, its been rearranged with a brand new usb board and some more suitable transformers will be here on monday.

but i'll post these pics just to get the ball rolling and to give a few ideas.

will post more during next week. at this point i still hadent figured where i was going to put the caps, was pretty crowded, thus moving to 2 box build and dual diff

Congrats nice job, how do you fix the heatsink to chassis?
 
thanks, there is m4 tapped holes in the corners, i use metric m4 threaded rod bolted through the floor. in that pic it was just sitting there. i also have some m4 titanium bolts on the way to use. to find such hardware, look at motobike/motocross racing parts supplies stores online.
 
Hi Guys,

This will be the official build thread for the I/V stage PCB group buy. Please post all build related questions here.

Also, feel free to post pictures of your build, chassis ideas, parts suggestions etc...

I'll start things off with a final schematic and SMD BOM which people will need for the build. I'll have a BOM posted for the remainder of the PTH parts, and it will include all the parts I used in my build.

Cheers,
Owen

Hi Owen,

How to buy this PCB ?
 

opc

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Merlin:

You'll have to clarify exactly what the problem is. The datasheet does not specify a maximum input voltage, or a maximum output voltage, but rather, a maximum input to output differential of 40VDC. That means you can put whatever voltage you want on the input, so long as the output isn't more than 40V lower.

I've been using my board with the LM317 and LM337 for a year now, without a single problem.

Going from 56V down to 45V won't be a problem for those regulators.

JBdv:

I'm glad you got your hands on kit! I think you'll enjoy it very much.

I'm sure qusp still has a few matched fets hanging around, and I think he also had some other goodies like z-foil resistors and whatnot. Ping him for more details.

The heatsinks are probably all gone by now, but it doesn't hurt to ask. If not, I'm sure qusp will share his drawing.

Let me know if you run into any troubles during the assembly. If you're quick, you could have it up and running by tonight!

Cheers,
Owen