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Buckeye Purifi Eigentakt 1ET9040BA monoblock power amplifier Stereophile Measurements

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The supply core doesn't even know about the input voltage and thus doesn't behave any different

Ah, yes it does. The supplies are optimized for high side full rectification and the losses are roughly -10% for low side voltage doubling. EU/AU/UK supplies outperform the same supply switched for US voltage.
 
Being an audio heretic, I have better results with industrial SMPS like MeanWell, than with “audio” SMPS like Hypex. Those industrial SMPS have both line and load regulation, thus independent on mains voltage fluctuations. They also provide detailed test reports, that you almost never find for “audio grade” units. And the price is much more acceptable. Just make a choice of the one with rated current high enough. I only add reverse voltage parallel protecting diodes.
 
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Being an audio heretic, I have better results with industrial SMPS like MeanWell, than with “audio” SMPS like Hypex. Those industrial SMPS have both line and load regulation, thus independent on mains voltage fluctuations. They also provide detailed test reports, that you almost never find for “audio grade” units. And the price is much more acceptable. Just make a choice of the one with rated current high enough. I only add reverse voltage parallel protecting diodes.
We use some MeanWell "off the shelf" PSU products in our high-availability production/distribution environment - and I also use them for misc items at home. They have served all applications exceedingly well.
 
We use some MeanWell "off the shelf" PSU products in our high-availability production/distribution environment - and I also use them for misc items at home. They have served all applications exceedingly well.
Should someone mail them maybe? ;)
 
Ah, yes it does. The supplies are optimized for high side full rectification and the losses are roughly -10% for low side voltage doubling.
Isn't that more or less what I wrote? The core only sees the final 320V or so DC voltage.
 
"This is a review and detailed measurements of the Purifi 1ET400A Class-D amplifier module. Company was kind enough to send me a complete, assembled kit consisting of two modules, power supply and case, ready to go"
And since then (which was 2019 I believe)?
 
And since then (which was 2019 I believe)?

Afaik, the only recent Purifi reference to a Hypex supply is in the 6525 app note. They do not make a comparable ref for the 9040.

Otherwise, Purifi’s design documents are very open and flexible about power supply specs and do NOT endorse Hypex or any other vendor specifically.
 
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And since then (which was 2019 I believe)?
The point is once they built a reference design, they broadcast to OEMs everywhere its ok to take our reference design and tweak it to your liking as needed. Some OEMs hardly changed anything, even the buffer board that they could have modified to their liking. Others with the engineering chops designed their own buffer boards in addition to a few extras of their own.

This is how its done everywhere in electronics design to speed up faster time to market. If you want to use the latest chips, wait for the manufacturer's reference board designs, which were used to test and validate their chips performance. Then you modify the design to your own application needs. This is how I and my fellow engineers do it, a method that has worked wonders for ages, to the manufacturer's delight, I'm sure when they see increased orders for their products.
 
Afaik, only recent reference to a Hypex supply is in the 6525 app note. They do not make a comparable ref for the 9040.

Otherwise, Purifi’s design documents very open and flexible about power supply specs and do NOT recommend Hypex or any other vendor.
See my post above
 
Perhaps @restorer-john can correct me, because he's had a much wider range of devices on the bench than I have or @SIY , but I seem to recall throughout history that most domestic power amplifiers have non-regulated supplies feeding the output, current-delivery stage. This is why recovery from impulse is a useful test for showing PSU lag etc.
 
See my post above

I stated the facts as an engineer who works with Hypex and Purifi. Not disputing your general experience but if you want to verify, both companies are very good at responding to email.
 
Ah, yes it does. The supplies are optimized for high side full rectification and the losses are roughly -10% for low side voltage doubling. EU/AU/UK supplies outperform the same supply switched for US voltage.
Just like computer enthusiasts overclock their CPU's, I would have thought any US based audio guy would have his own wiring with at least 230v :cool:
 
The point is once they built a reference design, they broadcast to OEMs everywhere its ok to take our reference design and tweak it to your liking as needed. Some OEMs hardly changed anything, even the buffer board that they could have modified to their liking. Others with the engineering chops designed their own buffer boards in addition to a few extras of their own.

This is how its done everywhere in electronics design to speed up faster time to market. If you want to use the latest chips, wait for the manufacturer's reference board designs, which were used to test and validate their chips performance. Then you modify the design to your own application needs. This is how I and my fellow engineers do it, a method that has worked wonders for ages, to the manufacturer's delight, I'm sure when they see increased orders for their products.
Trying to follow along, but it's hard because it appears a post in the quote link chain was deleted. Are you referring to the 1ET400A reference design as quoted by @Buckeye Amps above? If so, why would anyone think the power supply in the reference design for that module would be appropriate for the 1ET9040BA under discussion here?
 
The point is once they built a reference design, they broadcast to OEMs everywhere its ok to take our reference design and tweak it to your liking as needed.
Huh?

The original point/OP post was in regards to implying Purifi endorses Hypex specifically as the SMPS users and/or OEMs should choose. There may be sporadic mention of it but they definitely do not advertise the Hypex SMPS in a way a collaboration or sole endorsement would reasonably suggest.
 
Does anyone know why Purifi recommends the Hypex 1200W power supply, knowing it cannot provide the full rated power of 1400W into 2 ohms of the 9040BA module? With this Hypex power supply, the 9040 is able to deliver a maximum of 1050W to 1100W into 2 ohms. Why not recommend another one, like the Microaudio 1500W PS, able to deliver the spec'd 1400W?

Does Purifi have some form of a contractual relationship with Hypex to only use their power supplies, maybe due to the former history of the design engineers with Hypex?
This post is what I am referring to for clarity.
 
most domestic power amplifiers have non-regulated supplies feeding the output, current-delivery stage.
That has been my experience. I think I *may* have seen one solid state A/AB/B amp with output stage voltage regulation cross my path, but the vast majority were just transformer-rectifier-cap bank. I've seen a few more tube amps with regulation (I use it extensively in my tube designs). but they're still the exception. Nearly all the Class D amps in my house (and I have quite a few of them) use regulated supplies.
 
Trying to follow along, but it's hard because it appears a post in the quote link chain was deleted. Are you referring to the 1ET400A reference design as quoted by @Buckeye Amps above? If so, why would anyone think the power supply in the reference design for that module would be appropriate for the 1ET9040BA under discussion here?
I'm not saying they should be using the same PS for the 9040. No, the point I was making is that when Purifi used a Hypex power supply in their 1ET400 amplifier reference design, which was a design-to-be emulated-by-all-everywhere-and-modify-as-needed, it was a form of endorsement that its ok for OEMs to use the bill of materials for that amp as a starting point. They haven't built a mono or stereo versions for the newer 9040BA modules as far as I know.

EDIT... sorry about the deletion of earlier post as I somehow messed up the posted images and couldn't easily reverse my errors, so I figured its best to delete and start over again.
 
That has been my experience. I think I *may* have seen one solid state A/AB/B amp with output stage voltage regulation cross my path, but the vast majority were just transformer-rectifier-cap bank. I've seen a few more tube amps with regulation (I use it extensively in my tube designs). but they're still the exception. Nearly all the Class D amps in my house (and I have quite a few of them) use regulated supplies.
Thanks @SIY my recollection is similar. I actually owned a Deltec DPA50S Class A/B power amplifier with regulated supplies, but that's the only one I came across. Subjective reviewers at that time considered regulated power supplies made amplifiers sound non-dynamic (perhaps due to a lack of unregulated burst capacity).
 
Huh?

The original point/OP post was in regard to implying (that) Purifi endorses Hypex specifically as the SMPS users and/or OEMs should choose. There may be sporadic mention of it but they definitely do not advertise the Hypex SMPS in a way a collaboration or sole endorsement would reasonably suggest.

Agree, and as you know, despite the potential Hypex endorsement that the original Purifi reference amp might imply, the datasheet for the 1ET400A (and every Purifi amp module since) have supported a range of voltages that does not show deference to any SMPS vendor. For that matter, would suspect that Purifi uses a bench supply that would show the best amplifier performance rather than be potentially limited by a specific vendor's supply.

Purifi's datasheets publish power output measurements across the range of supported input voltages. If Purifi really wanted to endorse Hypex as their recommended supplier, would expect the specs to be very close to a specific Hypex SMPS. For that matter, would expect that the performance measurements would also specify a Hypex supply. This is not the case for either Purifi specs or measurements.
 
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