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Review and Measurements of Purifi 1ET400A Amplifier

David_M

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It's really simple. Set the jumpers as shown in the picture for enabling the gain stage. Have jumper shorts across all 4 terminals horizontally as shown in the picture.
 

Kelims

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Can you explain why it is better on ...... 4V and not 5,2V I mean the input and output sensitivity should be comparable
 

David_M

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Due to the high overall gain of 27dB, I believe with 5.2v, you'll clip the amplifier way before you reach the 5.2v output, meaning you don't get to use its full dynamic range. But the 4v, you'll have a much better chance of using the entire 4v range before clipping, hence taking advantage of the D90SE's full SINAD and DNR at full signal.

Anyways, try both options and see what sounds best to you, if any.
 

anphex

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Since I've already got two Hypex Monoblocks and I still want to try out a EVAL2 Monoblock configuration, is there a relatively easy way to switch out the NC400 at its position inside the case for the EVAL2 and somehow use premade cables to connect to the wiring ports at the case back? This way I could reuse the SMPS and case.

Edit: looking at the EVAL2 connector board it just like some twisted wire from the speaker ports to the case ports would suffice. Question is how to connect the XLR in of the EVAL2 connector board to the back of the XLR in on the hypex case. Maybe I don't even need to use an EVAL2 and can go straight for the 1ET400A but I can't wrap my head around how to wire this 23489 pin out thingy.

Edit2: looking at the XLR connector cable from Hypex again, I think even I might be able to open it up and just solder it a little to another plug so it's still removable.
 
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phoenixdogfan

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Since I've already got two Hypex Monoblocks and I still want to try out a EVAL2 Monoblock configuration, is there a relatively easy way to switch out the NC400 at its position inside the case for the EVAL2 and somehow use premade cables to connect to the wiring ports at the case back? This way I could reuse the SMPS and case.

Edit: looking at the EVAL2 connector board it just like some twisted wire from the speaker ports to the case ports would suffice. Question is how to connect the XLR in of the EVAL2 connector board to the back of the XLR in on the hypex case. Maybe I don't even need to use an EVAL2 and can go straight for the 1ET400A but I can't wrap my head around how to wire this 23489 pin out thingy.

Edit2: looking at the XLR connector cable from Hypex again, I think even I might be able to open it up and just solder it a little to another plug so it's still removable.
Why not disassemble an XLR plug and use the prongs to plug into the Eval 2. Then run wiring to the XLR inputs on the back of the Hypex case.

Like this:

https://www.audiosciencereview.com/...iy-purifi-amp-builds.10478/page-8#post-296386

You could also use banana plugs without the housing

 

mocenigo

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Since I've already got two Hypex Monoblocks and I still want to try out a EVAL2 Monoblock configuration, is there a relatively easy way to switch out the NC400 at its position inside the case for the EVAL2 and somehow use premade cables to connect to the wiring ports at the case back? This way I could reuse the SMPS and case.

If these are NC500 monoblocks then the SMPS is most likely a 1200A700 with (IIRC) 84V. The over voltage protection of the Purifi modules will shut them down over 75V and so you need a 1200A400 that delivers 72V. Otherwise the modules will not start.
 
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anphex

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If these are NC500 monoblocks then the SMPS is most likely a 1200A700 with (IIRC) 84V. The over voltage protection of the Purifi modules will shit them down over 75V and so you need a 1200A400 that delivers 72V. Otherwise the modules will not start.
Don't worry, it's NC400 and two SMPS600N400. Should match the EVAL2 just fine.
 

birkbott

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Anyone know what the difference is between the Apollon Purifi 1ET400A Mini and Stereo amps are? There are no pictures of the inside of the stereo amp but it’s considerably more expensive for what looks like the same specs and functionality. Aside from the larger chassis is there an additional power supply? Or is it in the op amps?
 

grobalt

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email :)

do the 1et400a create pop when turned on via 230v ? I ask as i have multiple to build and i have power distribution units with switchable plugs :)
 

birkbott

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email :)

do the 1et400a create pop when turned on via 230v ? I ask as i have multiple to build and i have power distribution units with switchable plugs :)
This would also pertain to me I use a master switch, I hate pops.
 

jmillar

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Real world? Maybe a very good PA from Germany or Austria. Only € 579 at home, Spain.

PAS 2002PCA, with input CMRR > 90 dB

https://www.thomann.de/intl/pas_2002pca.htm

View attachment 28917

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View attachment 28919

PS: I have been researching for years to buy or build an amplifier for my second audio equipment, so I have saved a lot of information. Meanwhile I have been experimenting with the one I have until I get an excellent sound. Problem: I think I have reached the maximum possible improvement. The sound is still 2D (less than the original) but I would like it to be 3D and to perceive sound planes plans with certain very good recordings.
Nice, sensible, comprehensible, repairable, discrete components, no surface mounting. Looks good! No measurements?
 

mocenigo

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email :)

do the 1et400a create pop when turned on via 230v ? I ask as i have multiple to build and i have power distribution units with switchable plugs :)

No pop, rather a very soft click (from the speakers).
 

Matias

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Anyone know what the difference is between the Apollon Purifi 1ET400A Mini and Stereo amps are? There are no pictures of the inside of the stereo amp but it’s considerably more expensive for what looks like the same specs and functionality. Aside from the larger chassis is there an additional power supply? Or is it in the op amps?
There are inside pictures in both product's pages. The mini uses a single power supply and a simpler, IC based buffer board, while the full sized uses 2 power supplies, one for each module, and the fancier buffer boards with discrete voltage regulators and choice of discrete opamps, which many will.say do not matter but still.
 

kuba-phase

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Hello! Great forum, great people :) I would like ask something. Now i have amp SMSL VMV A2 (Class D). It was tested here and score 95dB SINAD. Hard to ignore is fact it has build in "DAC" which is very convenient (actually it's not DAC, but it is not important now). This amp/dac is in "blue" region of SINAD :) My goal is to squeeze as much high quality sound, as I can afford (I'm more on the science side than the "audiophile" ;) In my "money range" is possible to buy good DAC (like RME ADI-2) and Purifi amp, like this one tested (at the beginning of this thread). My speakers are big, 3 way floorstander (Faital-3WC-15 Troels Gravesen). The question is: Is it possible to hear any difference with Purifi and ADI compared to VMV A2? SINAD RME and Purifi is much higher than VMV A2, but logic says that VMV A2 already is in "transparent department". Now, I can't hear any noise coming from speakers, well.... I have to literally put me ear into tweeter to hear something. I don't hear any distortion nether. But I wonder, will be there any sonic difference, stereo effect, any differences that will expose superior Purifi/RME combo? In terms of power I don't need much power, VMV A2 has more power that I need. PS: Sorry for my English.
 

boXem | audio

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Hello! Great forum, great people :) I would like ask something. Now i have amp SMSL VMV A2 (Class D). It was tested here and score 95dB SINAD. Hard to ignore is fact it has build in "DAC" which is very convenient (actually it's not DAC, but it is not important now). This amp/dac is in "blue" region of SINAD :) My goal is to squeeze as much high quality sound, as I can afford (I'm more on the science side than the "audiophile" ;) In my "money range" is possible to buy good DAC (like RME ADI-2) and Purifi amp, like this one tested (at the beginning of this thread). My speakers are big, 3 way floorstander (Faital-3WC-15 Troels Gravesen). The question is: Is it possible to hear any difference with Purifi and ADI compared to VMV A2? SINAD RME and Purifi is much higher than VMV A2, but logic says that VMV A2 already is in "transparent department". Now, I can't hear any noise coming from speakers, well.... I have to literally put me ear into tweeter to hear something. I don't hear any distortion nether. But I wonder, will be there any sonic difference, stereo effect, any differences that will expose superior Purifi/RME combo? In terms of power I don't need much power, VMV A2 has more power that I need. PS: Sorry for my English.
Frequency response vs load and max power vs load are much more important parameters for an amplifier than SINAD.
 

kuba-phase

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Frequency response vs load and max power vs load are much more important parameters for an amplifier than SINAD.
Ok, thanks for explaining. I am not good at electronics. I thought that's the point of SINAD ranking; to shows amp ranking (higher SINAD = better amp). Now I know there are more important parameters that SINAD. But I'm still curious, about changing VMV A2 to purifi amp + adi dac. Will it be any audible differences? What is Your opinion?
 
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