dpac996;167292 Wrote: > On another note I bought a welborne labs squeezebox linear power supply.
i just came across that last night... it looks pretty similar to the other ones on the market, for better or worse (a little of both actually). but the price, while still too high IMO, is more reasonable than the alternatives. i'm currently in the process of building a SB PSU from scratch. have been researching my design options for a few months now... but more on that later. tomjtx;167327 Wrote: > > I spent 2 weeks auditioning a modded SB2/PSU that sells for 2,500.00. > sorry, but a SB supply that costs 4 digits is nothing short idiotic. for that amount you should be able to build a no-holds-barred power supply for a power amplifier. or as you rightly point out, a Transporter... +5V @ 2A with good regulation, low noise, low broadband impedance and good transient response, while not as easy as some may think, is not complete rocket science. and as Mr. Adams has pointed out, the fruits of your labor are ultimately limited by the internal supply rails anyway. i also wouldn't be surprised if the $2500 supply does not really do a better job in these respects than a well-designed commercial supply, as your listening bore out... a lot of "audiophile" supplies actually have terrible, terrible design flaws... like dpac it also irks me to see the $750 supplies which use the most run-of-the-mill parts like a LT1086 in totally generic implementations straight out of a datasheet/DIY forum. as if that weren't bad enough, they throw in some total faux pas warned against in said datasheet, like putting a 2 meter wire between the regulator and load (squeezebox), or adding undamped "designer" film bypass caps which are pretty much guaranteed to add a nice ringing to the line when exposed to the high-speed load transients of a digital device like the SB. yet people seem to be happily snapping these things up, probably for lack of better options... oh well. anyway, enough bashing, and on to a more constructive note. i think i am close to selecting a regulator... unfortunately the Jung-based "super regs" are too low in current (most top out around 300mA), and i'm too lazy/unskilled to figure out how to modify it for increased current capacity without degrading performance. so i might go with the LT1963, which has an improved topology compared to the typical LMx17 stuff, and much better noise performance than the LT1086 (40uV max vs. 130uV, specified over a wider band too). only downside is reduced ripple rejection, so i might look into a choke filter. i will probably make the main box an unregulated supply, and put the regulator in a little dongle at the very end of the DC power cable to the squeezebox. if you guys are interested i will keep you updated on my progress... happy new year! :) -- dorkus ------------------------------------------------------------------------ dorkus's Profile: http://forums.slimdevices.com/member.php?userid=3373 View this thread: http://forums.slimdevices.com/showthread.php?t=19822 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/lists/listinfo/audiophiles
