Quote Originally Posted by mervinb View Post
I could not resist the urge to add more teeth to my Gator, so I've applied the standard Murata reg (+5V only), better supply caps mods to the receiver/dac board. The sound, which was already good to begin with, started to get more 'life', but lacked the body / authority that my best dacs provided (highly modded Channel Islands VDA-1, Zhaolu 2.0). I looked carefully at the supplies for the Gator, and felt that given the lengths of pcb tracks taken by the supplies (+15V, +12V regulated), some extra caps would be useful. I used Silmic IIs. The results? Superb. This added body to the sound, without taking away the refinement and detail.
Hi Mervin,
did you notice faint tone on background in very quiet music passages (so muting cirtuit is not engaged) after applying Muratas?

From the moment i've applied Muratas i can hear this tone mainly on HD800's connected directly to phones out of caiman with gator, but it's also on fixed output to preamp. I can hear it only on quite high volume (over 12'o clock on caiman) to which i'm listening to in some quiet recordings..

I was experimenting a bit and found that when i'm using linear PSU and set voltage below 13Volt this tone dissapears completely. By coincidence 13V and up is the voltage when Muratas are expected to start actually "work properly". I allready tried to replace both Muratas with new ones, but situation is still the same

As it was mentioned elsewhere on AOS, another member had the same issue and solved it by applying about 330uF caps to Vin and GND of both Muratas. I've done the same, but then found out that although this will remove background tone, but unfortunately it adds unpleasant noise to music when feeding caiman with 13Volt or more (up to 15,4V which is possible with my linear PSU, or original Caiman PSU).

I'm thinking if it is caused byt switched nature of this regulators and if yes what kind of filtering would help to get rid of this tone on background..