gofar99 Messages: 1950 Registered: May 2010 Location: Southern Arizona
Illuminati (5th Degree)
Hi Wayne, both kinds of noise can be problems. But with my latest foray into SS preamps I use SMPS. In the ac powered one two of them. One for conversion of 90-240 VAC 50/60HZ into 12VDC and a second to turn it into +/-12 VDC. The parts count is quite low (below what a more common supply would have) cost is low, and the stability (regulated supply feeding a regulated supply is quite excellent. Noise is zilch, but easy to filter with a single 470uf bypassed with a 0.1uf on each leg. I do put the same in between the SMPS as well. The noise level in the output of the high gain phono / tape mode (60db gain with appropriate equalization) is at the noise level of my shop in the -103 or better level. For home brew stuff I doubt it gets any better than that.