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P = Vdc*Vdc / Z
The question I asked is simple: which is the graph of the output impedance of the 1200AS2 class D module?
Dropped in my Nord 1200AS in place of my Hattor NC500 based mono amps. Out of the gate the 1200 throws a spectacular soundstage, left, right, front, back and up. Very 3D and airy sounding with almost exaggerated detail. Sounding a little thin but it is early. It does some amazing things and is a very initial WOW sounding amp. A crazy contrast I thought about as I carried the Nord in the house under one arm. I remember needing a hand truck and some serious heave ho to get my Parasound A21 in the house. Maybe this is why it sounds a little thin
Inside Hattor NC500[IMG] http://www.hattor.com/images/nc500_premium/4.jpgHypex SMPS heatsink does not protect the NC500 module, bad decission. And short distance too.Same bad decission in Nord NC500. At least the distance is greater than in Hattor. Then is OK.[IMG] http://www.6moons.com/audioreviews2/nord/open1.jpgNord NC500 stereo[IMG] https://static.wixstatic.com/media/bee373_558296dd2b0946578b76a0aa1db06d3a~mv2_d_4032_3024_s_4_2.jpg/v1/fill/w_1120,h_840,q_85,usm_0.66_1.00_0.01/bee373_558296dd2b0946578b76a0aa1db06d3a~mv2_d_4032_3024_s_4_2.jpgApollo NC800SL, with NC500 in stereo, the Hypex SMPS heatsinks are better placed.[IMG] https://www.apollonaudio.com/wp-content/uploads/2018/02/Apollon-Audio-Hypex-Nc500-based-Amplifier-top.jpgRouge Audio STUDIO N-7, with NC500 in stereo, the Hypex SMPS heatsinks are better placed.[IMG] https://static.wixstatic.com/media/ae8ca7_84e167196cc94daf91064a01d65f4b7c~mv2_d_2529_2144_s_2.jpg/v1/crop/x_534,y_228,w_1739,h_1284/fill/w_600,h_443,al_c,q_80,usm_2.00_1.00_0.00/ae8ca7_84e167196cc94daf91064a01d65f4b7c~mv2_d_2529_2144_s_2.jpgI can see a RF/EMI filter.
The heatsinks works as a shield.The very expensive Hypex SMPS are of low RF/EMI radiation, so leaving a reasonable distance there will be no problems.If the case has space, the logical thing is to take advantage of that shield <- good engineering.
There are actually two types of AES-17 filters for Audio Precision analyzers.* One is internal and is designed to give you the standardized bandwidth for general work. That filter is NOT sufficient for class-D amplifiers, nor delta-sigma DACs with a lot of noise shaping. These products have such high slew rate that they screw up the front-end of the analyzer, resulting in erroneous THD measurements and may even confuse the auto-scalar.* For these measurements, you must use the external, passive AES-17 filter as I have been using...
Well, there are phase shift but much less than IcePower 1200AS2, 700AS2 or Pascal M-Pro modules. Better engineering with frequency/phase in Hypex NC400.
You made the same mistake with the three graphs you posted of class D amps (can't find the post now, it was yesterday or the day before). The first graph showed one amp's impedance response, while the other two graphs showed the phase of the other two amps' frequency response.
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