dorkus Wrote: > coincidentally i was just playing around with regulators today on my > Sony SACD player DAC supply. i recently reworked the entire supply on a > perfboard to get the impedance lower. i also added a RC "snubber", which > made a very appreciable improvement in sound quality. my values are not > optimal, i am using 5 ohms in series with a .047uF Pana P cap since > it's what i had on hand. this is one application of a film cap that is > ok IMHO in a high speed supply - as a HF stabilization element when > used in conjunction with series resistance, since the R dampens the > reactance from parasitic inductance. > > i had also changed the garden-variety 7805 regulator to a LT1086-CT5, > which is the 5V fixed version of the LT1086 you're using. someone told > me however that the LT regulators are *not* better sounding, and > actually have higher noise than many 78xx parts. while the adjustable > version obviously has better noise performance with proper decoupling > of the ADJ pin, some people feel the low-dropout design is not the best > for sonics. > > anyway, on that person's suggestion i switched back to a 7805, and he > was right - it sounds quite a bit better. interestingly, the difference > in sound quality between regulators was not as big as the impact of the > snubber, but that may be a function of me having the wrong RC values. > > in any case, thought you guys might find my results interesting. i > should emphasize that this PS stuff is not as simple as it may seem - > "better" parts do not equal better sound quality. > > btw, a very knowledgable person (the originator of the snubber idea > actually) told me to try the LM340T-5 regulator as an alternative to > the 7805. he also has the snubber values calculated already, so i may > give it a shot. > > cheers, > dorkus
Hi Dorkus When you said snubber, at first I thought you were talking about the putting RC's on each diode of the diode bridge. But, I think you are talking about a RC filter, either before or after the voltage regulator. I am guessing you put it before the regulator, after the big lytic that would be after the diode bride, effective making a CRC filter. Is this what you did, or am I way off? Randy -- randytsuch ------------------------------------------------------------------------ randytsuch's Profile: http://forums.slimdevices.com/member.php?userid=3783 View this thread: http://forums.slimdevices.com/showthread.php?t=19822 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
