Interest in Modded B&K ST - 202 - SoCal only

rburgess714

I have not been active on this forum for some time, but I jumped down the rabbit hole in 2016. This forum definitely gave me good advice and helped me spend my money. I purchased this amplifier from an 80-year-old audiophile who had it modified. Guy was an industry guy. When I picked up the amp, I had never seen so many different systems in one house.


Checking for interest in the local Southern California market. Don't need to sell, but it has been sitting in my closets for years until the last couple of weeks, when I paired it with an older Parasound P5. Remarkable combo. If there is any interest, please message me.

Here are the modifications and benchmark test.

The modifications below were performed by the person I purchased the amp from.

The amp was from the original series, which had the more reliable, superior Hitachi TO-3 output devices, not the later plastic ones. Unit was upgraded to the Plitron power transformer and 2SK176 and 2SJ56 outputs. The new transformer significantly increases power output. These straightforward modifications provide a sonically accurate, reliable amp with serious power. The power cord was also replaced with a larger one.

Power developed at 8 ohms, both channels operating just under clipping:
100Hz: 231 watts left, 227 watts right.
1KHz: 242 watts left, 246 watts right.
10KHz 229watts left, 230 watts right.

Power at 4 ohms: (same conditions as above)
100Hz: 343 watts left, 348 watts right.
1KHz: 357 watts left, 348 watts right.
10KHz: 331 watts left, 334 watts right.

Power measured into non-inductive loads, both channels operating at full power just under the onset of clipping. DC offset is set to 0mv after 120 minutes of idle, both channels loaded, and the unit has been biased to eliminate all crossover notches. All measurements and alignments were performed correctly.