2nd generation EIGENTAKT PURIFI 1ET6525SA (successor to the 1ET400A)

[Chaos01]

About what temperature differences in measured heat are we talking here?
Does the NCx get warm or hot? i mean my Marantz Cinema 50 is even in idle very warm...
So cool purifi or more power hypex, whats better or smarter to buy for use at home?

And do you have information sources about the Heat dissipation informations?
Thanks
Edit: in the power test video from Apollon the Hypex ncx gets to 66 or 80°C i think?
Found more information Here, enough maybe
Post in thread 'Deciding Between NCX500, Purifi Eigentakt and Nilai' https://audiosciencereview.com/foru...purifi-eigentakt-and-nilai.45744/post-1999271

 

[rsg]

From my experience, what make the main difference between "hot" and "cool" in daily home use are the idling losses. 1.6 W vs 5.3 W (wich is already very good).

Thanks. I would assume that this means on the Hypex based modules, one would have to use better heat sinks to mount them on. That is if heat dissipation is an issue during operation.

I'll make some measurements with an infrared thermometer once I get my Purifi based amp and compare them to my Hypex NCx500 based amp.

 

[boXem]

That is if heat dissipation is an issue during operation.

Having recently dismantled a 5 years old NC500 based amp from a competitor, I can guarantee that heat dissipation can be an issue during operation: everything inside was looking like out of an oven... No surprise that one of the PSs exploded.

 

[rsg]

Having recently dismantled a 5 years old NC500 based amp from a competitor, I can guarantee that heat dissipation can be an issue during operation: everything inside was looking like out of an oven... No surprise that one of the PSs exploded.

Wow, PS exploded? It should have shut down. That would be a fire hazard.

A 5 year old would be the previous NC500 modules? The current NCx500 is from 2022 or 23?

 

[amper42]

In a fully open air environment where turning the amp off when not in use is standard practice, the Hypex amp can last a very long time. But leave it on 24 hours a day (even in idle) can increase long term strain on components. And if the Hypex is installed in tight spaces, stacked or in a closed cabinet it can multiply the heat issue. Design challenges can also increase heat. Install 4-8 channels of Hypex modules in a single case and you have a space heater.

 

[boXem]

Wow, PS exploded? It should have shut down. That would be a fire hazard.

A 5 year old would be the previous NC500 modules? The current NCx500 is from 2022 or 23?

The safety mechanisms made their job, customer was really afraid but not any trace of flame.
Yes, old NC500 that was heating a lot more than the NCx500.

And if the Hypex is installed in tight spaces, stacked or in a closed cabinet it can multiply the heat issue.

Don't underestimate the power of dust.

 

[pma]

I am saying that Hypex NCxxxMP modules with SMPS need such heatsink as I do use. Then it can be turned on night and day and continuous maximum power is limited only by the distortion curve. I am torturing the amp since December 2021 without any issue. But to screw it at the bottom of the Al case is not enough. Purifi 1ET400A does not need such good heatsink.

 

[jamesdyson]

@pma I did ask march audio about the thd+ V snr on their forum. Alan confirmed that at the 5 watts point, their is no significant difference between the two.

New P482 Stereo Power Amplifier

Hey Alan On ASR there was a question regarding the validity of your corrected SINAD figure. The poster said it wasn't valid because the noise floor increases with increasing power output. Therefore just taking the shorted input noise figure doesn't account for the increased noise at higher...

forum.marchaudio.com

They also have released 3 1et6525 based amps. Appear to have the best measurements for this module that I have seen so far.

Home - March Audio - High End Purifi Audio Amplifiers and Speakers

Purifi Audio Amplifiers and Speakers

marchaudio.com

 

[bricesan]

As long as the amplifier you choose has a sensitivity below 5.2 V RMS, i.e. a gain above 18,4 dB, you will be able to get full power out of it.
These modules are to be integrated with an input/gain stage that is specific to each manufacturer. There is no direct link between the upstream component (DAC or pre) and the module.

exept for audiophonics version where the input stage can be bypassed

 

[bricesan]

I answered once but reread qustion. Low gain is also suitable. High Gain is just my preference. I think impedance (reactive part of it) proportion is fine.
30 may of 2022 I asked directly Bruno Putzeys via email with this question

I got answer:

Before this also were question from me.

And answer

I thanked Bruno.

I used Eval1 with hg, lg both. I stay with hg now (buffer is on) because of color or something. But electrically there should be no problem.

i use a lynx aurora n as my dac and to my ears i much prefer the sound without input buffer

 

[amper42]

@pma I did ask march audio about the thd+ V snr on their forum. Alan confirmed that at the 5 watts point, their is no significant difference between the two.

New P482 Stereo Power Amplifier

Hey Alan On ASR there was a question regarding the validity of your corrected SINAD figure. The poster said it wasn't valid because the noise floor increases with increasing power output. Therefore just taking the shorted input noise figure doesn't account for the increased noise at higher...

forum.marchaudio.com

They also have released 3 1et6525 based amps. Appear to have the best measurements for this module that I have seen so far.

Home - March Audio - High End Purifi Audio Amplifiers and Speakers

Purifi Audio Amplifiers and Speakers

marchaudio.com

The power specs quoted on the March Audio site are the manufacturer specs. You will want to take them with a grain of salt.

If you live in the USA the problem with March Audio is price. Not only does March charge more for the amp, but shipping is more than double what Boxem charges. March charges $122 for shipping a Purifi amp to the USA. Boxem is about $48 in comparison and Buckeye is free.

If you put all three brands on an AB switch and move between them in a blind test you won't be able to reliably distinguish which one is playing. So it comes down to looks, which to be honest at 8' to 11' away is not that different. Maybe if it sits 2' in front of you while listening you may prefer the Boxem or March case?

Bottom line, choose your Purifi amp from the source you TRUST to service you after the sale. How expensive is it to have it repaired out of warranty? How easy is it to get a response from the company? When you do get a response does it fully answer your question? Do they ship in a timely fashion? Do they post measurements on their site that were verified with their build? Or is it just the Purifi module spec? How flexible are they with special requests? You get the idea. Looking for .0001 better posted measurements from the builder will likely be a mirage and in the unlikely event it's true will never be heard.

 

[boXem]

exept for audiophonics version where the input stage can be bypassed

As long as people understand what it means, good for them.

 

[jamesdyson]

The power specs quoted on the March Audio site are the manufacturer specs. You will want to take them with a grain of salt.

If you live in the USA the problem with March Audio is price. Not only does March charge more for the amp, but shipping is more than double what Boxem charges. March charges $122 for shipping a Purifi amp to the USA. Boxem is about $48 in comparison and Buckeye is free.

If you put all three brands on an AB switch and move between them in a blind test you won't be able to reliably distinguish which one is playing. So it comes down to looks, which to be honest at 8' to 11' away is not that different. Maybe if it sits 2' in front of you while listening you may prefer the Boxem or March case?

Bottom line, choose your Purifi amp from the source you TRUST to service you after the sale. How expensive is it to have it repaired out of warranty? How easy is it to get a response from the company? When you do get a response does it fully answer your question? Do they ship in a timely fashion? Do they post measurements on their site that were verified with their build? Or is it just the Purifi module spec? How flexible are they with special requests? You get the idea. Looking for .0001 better posted measurements from the builder will likely be a mirage and in the unlikely event it's true will never be heard.

I don't see a reason to doubt the power numbers. I have done a lot of research on these competing amps and the March power data is consistent with what's in the datasheet. They just don't have an undervoltage Hypex PSU. This is measured data not module spec. Still waiting to see more comprehensive measurement data from other manufacturers.
I ordered a March Audio P482 yesterday. It's shipping from stock so no delay from build time. Should have it in the UK by next Monday. I considered the things you mention and have no reason to doubt March and trust they will offer excellent service. 5 year standard warranty. Looks? Well personally I dont want cheap bent sheet for a case. Anything better is similarly priced. So far had excellent comms by email and on their forum. I like the extra attention to detail which provides the best performance. I will let you know how I get on.

 

[rsg]

Some initial temperatures of the boXem A 4216/E4 using a an infrared thermometer with laser pointer. 4-channel Purifi 1E6525SA module based amplifier.

1. No load and turned on idle for >1 hour.
2. Ambient air temp around 76F (24.4C) with low humidity.
3. The top of the chassis is 89F (31.6C).
4. The outer two modules are cooler than the two inner ones. Outer two are around 102F (38.9C).
5. Inner modules are >106F (40.5C)
6. The Hypex SMPS3K power supply transformer is >118F (47.7C)
7. The power supply's large capacitors are at 91F (32.7C)

The heat sink plates look large, but heat venting is at bottom of chassis. The modules are mounted upside down which is an interesting design choice, but I assume this was done to avoid dust accumulation and accidentally spilling liquids in to the unit by mistake. Mine will be in a cabinet, so I will have to raise the feet by 1 inch (2.5 cm) and ensure adequate air flow.

These temperatures of the modules and PS are higher than my 3-channel Buckeye NCx500 amplifier with the Microaudio SMPS2K power supply. It too has good sinks.

 

[boXem]

Some initial temperatures of the boXem A 4216/E4 using a an infrared thermometer with laser pointer. 4-channel Purifi 1E6525SA module based amplifier.

Thanks for publishing these measurements

7. The power supply's large capacitors are at 91F (32.7C)

That's indeed the most important data: these are bulk caps on the mains voltage side. That makes them safety critical components whose ambiant temp must stay below the power supply rated ambiant temperature (50 °C).

The heat sink plates look large, but heat venting is at bottom of chassis. The modules are mounted upside down which is an interesting design choice, but I assume this was done to avoid dust accumulation and accidentally spilling liquids in to the unit by mistake.

Cold air intake is at the bottom of the chassis, hot air is leaving the box through the front and back vents (approx. 34 cm2). The idea of the upside down mounting came from experiments with an NC252MP whose power supply FETS are mounted below the bulk capacitors. Keeping these caps at reasonable temperatures with traditional flat mounting is quite ambitious but once you install the module upside down, heat-sinking almost becomes optional. And yes, I just hate dust in electronics, so grills on top of the chassis are a no go for boXem.
That said, there is always room for improvement and from mid December, a new heatsink allowing better bottom to top airflow around modules and PS will be used.

 

[rsg]

I'll get around to actually installing it at the end of this week or when I get some time as I have to travel out of town on business. The amp itself looks like a good solid build, the only negatives I can give on initial observation is that there is no LED on the front panel indicating the unit is on and there is no master on/off switch. This wouldn't be a problem if the venting were at the top where I could observe the Purifi module LEDs come on.

Can I purchase the new heatsink from you when you've cleared out your initial orders and install it myself and is there an on-line users manual for the A 4216 units?

Both Fred at boXem and Dylan at Buckeye Amps have been pleasure to deal with and have answered all questions. I wouldn't hesitate to purchase from either of them.

 

[amper42]

Some initial temperatures of the boXem A 4216/E4 using a an infrared thermometer with laser pointer. 4-channel Purifi 1E6525SA module based amplifier.

1. No load and turned on idle for >1 hour.
2. Ambient air temp around 76F (24.4C) with low humidity.
3. The top of the chassis is 89F (31.6C).
4. The outer two modules are cooler than the two inner ones. Outer two are around 102F (38.9C).
5. Inner modules are >106F (40.5C)
6. The Hypex SMPS3K power supply transformer is >118F (47.7C)
7. The power supply's large capacitors are at 91F (32.7C)

The heat sink plates look large, but heat venting is at bottom of chassis. The modules are mounted upside down which is an interesting design choice, but I assume this was done to avoid dust accumulation and accidentally spilling liquids in to the unit by mistake. Mine will be in a cabinet, so I will have to raise the feet by 1 inch (2.5 cm) and ensure adequate air flow.

These temperatures of the modules and PS are higher than my 3-channel Buckeye NCx500 amplifier with the Microaudio SMPS2K power supply. It too has good sinks.

The sweet spot for minimal heat is two Purifi modules (Stereo) and a standard Hypex SMPS1200 power supply. Once you start using the same case to house four modules and a SMPS3K the challenge to maintain a cool operation is significantly magnified. Purifi stereo amp configurations run cooler by design.

 

[boXem]

I'll get around to actually installing it at the end of this week or when I get some time as I have to travel out of town on business. The amp itself looks like a good solid build, the only negatives I can give on initial observation is that there is no LED on the front panel indicating the unit is on and there is no master on/off switch. This wouldn't be a problem if the venting were at the top where I could observe the Purifi module LEDs come on.

Can I purchase the new heatsink from you when you've cleared out your initial orders and install it myself and is there an on-line users manual for the A 4216 units?

No front LED is a design choice. Manual is in the ToDo list. Maybe we can take this conversation in the boXem A seies thread .

 

[rsg]

The sweet spot for minimal heat is two Purifi modules (Stereo) and a standard Hypex SMPS1200 power supply. Once you start using the same case to house four modules and a SMPS3K the challenge to maintain a cool operation is significantly magnified. Purifi stereo amp configurations run cooler by design.

I don't think it's a difficult design challenge. It comes down to case size, heat sink capacity and proper ventilation. I saw one DIY amp here on ASR that had 3/8" thick copper plates on each of 8 modules, two case fans, two PSs and a large chassis. It looked like a really nice build.

 

[boXem]

Well, I am hoping that you guys are not considering the temps measured by @rsg as "too high". Because they are frankly reasonable.
Engineering is meeting or exceeding a set of performance targets while meeting or being under a target cost. Getting the best performance at whatever cost is called a hobby. Nothing against it, but that is not how a company is run.
Heat spreader had to be modified due to manufacturing issues and solving these issues improved air flow as a nice side effect.