lucky we can have both with this circuit 
we can have < -110db thd plus noise with single stage, excellent!
BTW guys, dont know if anybody else is keen, or its just me thats this nuts; but i'm going to get the 400R from texas components, for 0.01% tX220Z (custom Zfoil power resistor) will be over 30USD a piece (under 35 though and only a dollar less for 0.1%, so may as well get 0.01)., pricey, but I think if going for thin film, may as well take it to the next level, well actually its another level again. they are not much use for the 200R as they are only rated for 10W but I think that will be fine for the 400R right opc?
I have asked my contact there about quote for a larger order of over 25 pieces if we can throw in and see if this can come down a bit if you guys are keen, doesnt take too many of us wanting them to use 25 devices only just over 6 boards. i'll keep the offer open for a week before I finalize the order with them for my own, so you can let me know by PM and we'll go from there, but again unless there is overwhelming interest I wont bother with a full blown GB thread, as I dont expect there will be that many of you keen.
neb001 got your PM mate, should be fine, they will be matched in pairs closer than quads, until I see the spread I cannot guarantee an 8 way match to a really high degree, will get as close as I can with what I have, but the 4 x pairs will be matched well as I can. hope that makes sense
we can have < -110db thd plus noise with single stage, excellent!BTW guys, dont know if anybody else is keen, or its just me thats this nuts; but i'm going to get the 400R from texas components, for 0.01% tX220Z (custom Zfoil power resistor) will be over 30USD a piece (under 35 though and only a dollar less for 0.1%, so may as well get 0.01)., pricey, but I think if going for thin film, may as well take it to the next level, well actually its another level again. they are not much use for the 200R as they are only rated for 10W but I think that will be fine for the 400R right opc?
I have asked my contact there about quote for a larger order of over 25 pieces if we can throw in and see if this can come down a bit if you guys are keen, doesnt take too many of us wanting them to use 25 devices only just over 6 boards. i'll keep the offer open for a week before I finalize the order with them for my own, so you can let me know by PM and we'll go from there, but again unless there is overwhelming interest I wont bother with a full blown GB thread, as I dont expect there will be that many of you keen.
neb001 got your PM mate, should be fine, they will be matched in pairs closer than quads, until I see the spread I cannot guarantee an 8 way match to a really high degree, will get as close as I can with what I have, but the 4 x pairs will be matched well as I can. hope that makes sense
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Hi Guys,
Definitely focus on grouping into pairs, since it's the pair in the diff pair arrangement where you see the advantage in distortion cancellation.
I had quite good matching in my set, and I only had to test 11 devices to get two pairs that were very closely matched in both TC and VDS.
Cheers,
Owen
Definitely focus on grouping into pairs, since it's the pair in the diff pair arrangement where you see the advantage in distortion cancellation.
I had quite good matching in my set, and I only had to test 11 devices to get two pairs that were very closely matched in both TC and VDS.
Cheers,
Owen
guys, best to use PM or email qusp (scrat) optusnet (grot) com (spot) au rather than cluttering up the thread. could everyone who has posted in here and hasnt PM'd or emailed me do so so I have it on record. got your email Stephen will get back to you later today, there is no rush, but as they take 3 weeks for production (they are made custom) I figured I would wait till tuesday next week and then send off the final order (although its all teed up), unless those interested get in contact really soon I could push it forward. I'm talking R's here that is, the fets are on the way, but wont be here for a week or 2 and i'm moving next week/weekend and need time to set up the workshop again. that should work out pretty decent timing anyway, but many more fets i'l have to think about, perhaps another 2-3 sets I can agree to until I see what the spread is. I'm sure there will be a few more than that, though not heaps more, but cant commit to more till I know.
i'm off to bed but all good at this stage....really
rather than cluttering up the thread. could everyone who has posted in here and hasnt PM'd or emailed me do so so I have it on record. got your email Stephen will get back to you later today, there is no rush, but as they take 3 weeks for production (they are made custom) I figured I would wait till tuesday next week and then send off the final order (although its all teed up), unless those interested get in contact really soon I could push it forward. I'm talking R's here that is, the fets are on the way, but wont be here for a week or 2 and i'm moving next week/weekend and need time to set up the workshop again. that should work out pretty decent timing anyway, but many more fets i'l have to think about, perhaps another 2-3 sets I can agree to until I see what the spread is. I'm sure there will be a few more than that, though not heaps more, but cant commit to more till I know.i'm off to bed but all good at this stage....really
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Hey guys,
Finally I got a source for Caddock MP930 400R at near 9€00 each & they have a stock of 23 resistors, link here:
RESISTORS Power resistors 30W 0.02Ω to 1KΩ heatsink mount resistor MP930 series
Finally I got a source for Caddock MP930 400R at near 9€00 each & they have a stock of 23 resistors, link here:
RESISTORS Power resistors 30W 0.02Ω to 1KΩ heatsink mount resistor MP930 series
Well I ordered two sets, because a lot of ppl were dropping out and I thought that I might have use for it later on.
That later on would definately be a lot of time from now, since I have a lot of work to do with my current projects.
So I could offer you one pcb and one smd-set, but you'll have to take a set of fets, too.
That later on would definately be a lot of time from now, since I have a lot of work to do with my current projects.
So I could offer you one pcb and one smd-set, but you'll have to take a set of fets, too.
Yea, I'm just crossing my fingers there is a second GB for these boards.
looks like you just missed another one :| if you ar4e dead keen and prepared to go to the trouble, I suppose its possible that you could get a batch PCB with opc's permission and help. they are pretty cheap these days for one off boards, well you would probably end up with 2 or 3. wouldnt be as high quality as ours, but should do the job. totally hinges on opc though and your willingness to go above and beyond
that being said, knowing how good this design sounds with the sabre, after feedback and impressions of this PCB come in, I would not be surprized if there was another run
Iloveswan: no sorry mate, dont have any experience with those fets. I think you'll probably find the difference is in the current rating, the FQA34N20 is rated for 34A and the FQA32N20 is rated for 32A. so are you saying you have some FQA34N20 on hand or FQA32N20? because the FQA32N20 is the one specified in the BOM, so you are good to go if thats what you have. either will do great.
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depends on the standoffs and heatsinks you use (or if you use the case for the sink), also the main supply caps, these are the tallest things on the board, so work that out and you have your height, because the dac will not be taller than the surrounding components
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