I have been thinking about his comment and your response. To be clear, I use HQP and I think it is a very good program. But, I also think it is very easy to be seduced by the power of big numbers. The idea that a 1.4 Mbps stream (44.1/16) raised to 90 Mbps via filters and dither will automatically sound better may not necessarily be true. I have experimented with my Spring 2 DAC and have found that many times using up-sampling does not improve the sound and sometimes as you found it makes it worse. On some material it does improve the sound. I now use no up-sampling (NOS) as my standard and I apply up-sampling selectively. At my age, my ears are acting as a filter as I no longer hear much above 10,000 Hz. I don't want to start an argument about all the ins and outs of up-sampling but I do want to make it clear that blanket assumptions about it may be wrong and case by case comparison is the appropriate method. Thanks again for a great review.