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Buckeye Amps: 2nd Generation Purifi EIGENTAKT 1ET9040BA Amplifier

o yes sorry i jus realised this thread is about 1ET9040BA and not 1ET6525SA :D. Yes i am asking abt the 1ET6525SA
With both the 3ch Purifi and 3ch Hypex NCx500, you would unlikely hear any audible difference. The choice mainly comes down to cost, availability, the better SMPS in the Hypex (for power/wattage), or just brand name preference.
 
but later I accidentally touched the output line to the outer casing, and as a result, the power amplifier burned out, and there was no subsequent testing.

Oh that's sad. Bridged amplifiers don't take kindly to chassis grounding.
 
Actually, I have also done a simple test on 1ET9040BA, using the instruments DCA+E1DA APU+E1DA ADC. The THD+N is 0.000066% at 1K, but when the load is connected, the THD+N rises to 0.00030%. Of course, it has something to do with the ground of my power supply. Maybe my power supply is not well installed and not fully installed in the chassis, but later I accidentally touched the output line to the outer casing, and as a result, the power amplifier burned out, and there was no subsequent testing.
What the f... their short circuit protection, overload protection did not protect this condition?
That's surprising...
 
What the f... their short circuit protection, overload protection did not protect this condition?
That's surprising...
For clarity, this is not one of our customers as far as I am aware
 
For clarity, this is not one of our customers as far as I am aware
Thanks, but isn't the protection provided by the module itself?
Is there difference in protection between yours 1ET9040BA module amps vs other amps?
Or is it that your amp won't have such problem as he mentioned?
Thanks!
 
Thanks, but isn't the protection provided by the module itself?
Is there difference in protection between yours 1ET9040BA module amps vs other amps?
Or is it that your amp won't have such problem as he mentioned?
Thanks!
The module has protection, yes.

More that I cannot comment on the problem he encountered because I don't know his exact setup (such as referencing to "his power supply")
 
What the f... their short circuit protection, overload protection did not protect this condition?
That's surprising...
Short-circuit and overload is one thing,grounding the (balanced) output of a bridged amp is another.
There has to be a specific protection about it and also stated specifically (and a bold warning also) .
 
Short-circuit and overload is one thing,grounding the (balanced) output of a bridged amp is another.
There has to be a specific protection about it and also stated specifically (and a bold warning also) .
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1ET9040BA - Data Sheet (1.10)
 
What the f... their short circuit protection, overload protection did not protect this condition?
That's surprising...
It should be protected, but my actual situation did happen, and it happened twice. Both times, the MOSFET burned out. Of course, it happened when I tested with a sine wave. Maybe the music was not a problem. My 9040 module was purchased from the official store of purifi. Due to poor insulation between my terminal post and the chassis shell, when the signal was increased, the terminal post and the chassis leaked and arced, and the cause was found only after the second damage. It has now been repaired and sold.
If I'm not mistaken, the protection threshold of the bridge amplifier is to monitor the sum of the two output currents. When only one side is connected to GND, the current on one side needs to be doubled to activate protection, which should exceed the current that MOSFET can withstand. There should be no problem with a short circuit between OUT+ and OUT-.
Those who have samples can try this operation, maybe it's just this one that has a problem. I dare not do 2OHM sine wave full power test, but those who are brave can try it.
 
It should be protected, but my actual situation did happen, and it happened twice. Both times, the MOSFET burned out. Of course, it happened when I tested with a sine wave. Maybe the music was not a problem. My 9040 module was purchased from the official store of purifi. Due to poor insulation between my terminal post and the chassis shell, when the signal was increased, the terminal post and the chassis leaked and arced, and the cause was found only after the second damage. It has now been repaired and sold.
If I'm not mistaken, the protection threshold of the bridge amplifier is to monitor the sum of the two output currents. When only one side is connected to GND, the current on one side needs to be doubled to activate protection, which should exceed the current that MOSFET can withstand. There should be no problem with a short circuit between OUT+ and OUT-.
Those who have samples can try this operation, maybe it's just this one that has a problem. I dare not do 2OHM sine wave full power test, but those who are brave can try it.
Conditions matter and matter a lot.
Here's a similar failure running NC502MP BTL at 4 Ohm to torture conditions.
Protections did kicked in but amp was destroyed:

 
Very few, almost no people will use the low gain setting. Most people will need to use the medium or high gain settings to match their source equipment. 4 volt xlr or 2 volt rca. These are the gains where amps should be compared as its most relevant to most users. Otherwise just bypass the input buffer and just claim the Purifi module performance.

Could you tell more about this, I plan to buy this amplifier to power Dynaudio S25 (200W 4ohm) spekars. I calculated required gain: Vout = sqrt(200 * 4) = 28.3 Vrms, Gain = Vout/Vin = 28.3 / 5.2 (my DAC have 5.2 Vrms) = 5.44, so 14.7 dB which is below "low gain" settings of 15.5 dB (which according to calculations could power 240W 4ohm at 100% DAC volume output). Should I use medium gain anyway? Or can I use low gain and maybe even bypass gain?
 
Could you tell more about this, I plan to buy this amplifier to power Dynaudio S25 (200W 4ohm) spekars. I calculated required gain: Vout = sqrt(200 * 4) = 28.3 Vrms, Gain = Vout/Vin = 28.3 / 5.2 (my DAC have 5.2 Vrms) = 5.44, so 14.7 dB which is below "low gain" settings of 15.5 dB (which according to calculations could power 240W 4ohm at 100% DAC volume output). Should I use medium gain anyway? Or can I use low gain and maybe even bypass gain?
All your calculations are correct, on the condition that you only want 240W into a 4 ohm load, which would be under-utilising a very capable amplifier.

I wouldn't over-think it. You can change the gain and see for yourself. Set the gain to low and see if it goes loud enough for you. They're quite efficient speakers, so it probably will.
 
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There's a review of the Buckeye Purifi 9040 amp in Stereophile by Kal Rubinson. I saw it via an Apple News+ subscription, so I posted the link below. I assume it will show up on the Stereophile website (and be in the print issue). I couldn't see all of the measurement figures via Apple News+. Not sure why. Perfect for driving your Estelon X Diamond Mk II reviewed in the same issue.

EDIT: If you subscribe via Apple News+, the measurements are shown by scrolling left and right. User error on my part.

 
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This will be fun. Can't wait to show up on the Stereophile website.
 
Let me just say, when I first started Buckeye Amps, never ever did I think it would be on the audio radar large enough to be noticed by a publication like Stereophile.

Thanks everyone!
 
Let me just say, when I first started Buckeye Amps, never ever did I think it would be on the audio radar large enough to be noticed by a publication like Stereophile.

Thanks everyone!
Hi,
For this review I subscribed the stereophile for 3mo.
Is the 19kHz+20kHz-IMD measurement result within your exception?

Edit: CCIF --> 19kHz+20kHz
 
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