P801 Power Amp

Alan March wrote:
Hi

As mentioned, we don't provide in depth design details. We won't be publishing detailed pictures of the design. The situation is that other less capable companies with inferior designs want to know how we achieve what we do. Whilst there is obviously a limit to what we can do, we are not going to make it easy for them to copy 😀.

Our current PSU has all the features you mention. It's not the one shown in the link. The Micro Audio BTW is effectively regulated. The Hypex is unregulated and it's output voltage goes all over the place with mains variations and loads.

Thanks for that Alan, that's understood but unless Micro Audio have made a mistake with their documentation, they advertise their SMPS1K-PFCR2 (erroneously listed as the SMPS1K-PFCR3 in the documentation) & SMPS1K-SN as "unregulated" as you can see below, perhaps the owner Sami has made an error with his documentations but not too sure about that.

Oniiz86 wrote:
Thanks for that Alan, that's understood but unless Micro Audio have made a mistake with their documentation, they advertise their SMPS1K-PFCR2 (erroneously listed as the SMPS1K-PFCR3 in the documentation) & SMPS1K-SN as "unregulated" as you can see below, perhaps the owner Sami has made an error with his documentations but not too sure about that.
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Hence my careful use of the word effectively.

The earlier models use feedback within the switching circuit to provide loose regulation. Which is actually quite effective compared to the performance of the Hypex design. However it will struggle with reactive load bus pumping. So possibly a bad description on my behalf, it's not fully regulated.

The lower voltage rails are fully regulated with traditional 3 pin linear regulators.

The later designs improve on this with the bus pumping control techniques that regulate the main high voltage rails.

As an aside to this, we do continually look at the design options for our products and operate a continuous improvement policy. As such components will change when we feel it's beneficial to do so.

@Alan March, thanks for the clarifications, Alan ... so, to summarize the capabilities of the P801, its power supply (designed by whoever) is fully regulated on all positive and negative rails, has no issues with bus pumping, and is a 4-quadrant design? And its line regulation spec <= 1% so as to make its main output DC voltages fully invariant to input mains fluctuations? Similar specs for load regulation into 8/4/2 ohm loads?

SmartOne_2000 wrote:
to summarize the capabilities of the P801, its power supply (designed by whoever) is fully regulated on all positive and negative rails, has no issues with bus pumping, and is a 4-quadrant design? And its line regulation spec <= 1% so as to make its main output DC voltages fully invariant to input mains fluctuations? Similar specs for load regulation into 8/4/2 ohm loads?

@SmartOne_2000 I believe you meant to say a 2-Quadrant design, this type of SMPS as you know is also available from Buckeye Amps for their Purifi ET9040BA Monoblock amp, they also have an exclusive 2kW SMPS from Micro Audio (SMPS2K-SN) for their 3 Ch Hypex NCx500 amp, it's great to see other manufacturers offering superior SMPS products rather than the typical Hypex solution.

Oniiz86 wrote:
@SmartOne_2000 I believe you meant to say a 2-Quadrant design, this type of SMPS as you know is also available from Buckeye Amps for their Purifi ET9040BA Monoblock amp, they also have an exclusive 2kW SMPS from Micro Audio (SMPS2K-SN) for their 3 Ch Hypex NCx500 amp, it's great to see other manufacturers offering superior SMPS products rather than the typical Hypex solution.

Thanks for the correction! (y)

@Alan March I was wondering is there any particular reason you no longer explicitly mention that the amps utilise the OPA1612 op amp, it was listed previously on the Purifi amp product pages, it just mentions "the highest performance op amps", you still list the type of ultra low noise voltage regulators LT3045/94 which are the best on the market, all other Purifi/Hypex OEM competitors mention the chosen op amp which I'd assume most potential customers would like to know, I know you have said time & time again that the OPA1612 is the best for noise & distortion performance but was curious if you've simply opted for something else in its place?