Some of you will remind me that I promised to post more measurements for Buckeye’s NCx500, but Dylan also had me busy with a couple of other tasks. Both involve MicroAudio (MA) supplies, but only one was already shipping. So, he sent me a new Purifi 7040 monoblock to test. One major test was to compare the 2 ohm performance of the Purifi 7040 using the MA supply. Fortunately, my new dummy load can be configured for 2 ohm testing and with some air cooling, worked out well. As a bonus, knew there would be interest in how it compared to being powered by the MA versus the Hypex A400.
So, here it is...
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As I have mentioned elsewhere, my high power dummy load is a bit noisy, so these plots are only
THD vs Power. The blue trace is the 7040 with the MA supply and the dark red one is the Hypex. At clipping, can see the amp yields about another 230 watts powered by the MA.
In a related topic, another forum question has been how the Purifi 7040 compares to the Hypex NCx500. The NCx500 here is a Buckeye 2 channel amp with the Hypex SMPS1200A700 supply. Am only drive one channel on the NCx500 but otherwise the conditions are identical (1kHz at 2 ohms). Here is that look...
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Using a different setup, I did verify that both amps were very low noise. While admittedly this is one simple comparison, my takeaway here is these amps perform similarly and would leave my decision to other criteria (like quality, price and features).