I used to replace the well known IMO rather destructive standard output coils of Class-D amps with custom-wound Mundorf copper air foil coils years back.
That worked extremely well on low power setups - due to low EMI.
"Very clean, airy and fast" - that's always been the impression.
Not any other coil I tried would beat that performance.
Many of us know what different type of coils do to the sound when used e.g. in crossovers.
The impact of coils is well known. And yep. It's IMO still a weak spot of Class-D.
It seems that Putzey finally figured something out.
"Granuarilty in sound" , as outlined in the report, can have a lot more causes though.
To list one more:
On Mundorf home you'll find measurements what vibrations on coils do to the signal/sound.
You IMO can add big caps to that list as well.
Once more. What I really consider a weak spot on the Purifi amp is the lack of vibration dampening.
After more time listening to the amp by now, I still can't say, I'm fallen in love with the Purifi amp.
Enjoy.
That worked extremely well on low power setups - due to low EMI.
"Very clean, airy and fast" - that's always been the impression.
Not any other coil I tried would beat that performance.
Many of us know what different type of coils do to the sound when used e.g. in crossovers.
The impact of coils is well known. And yep. It's IMO still a weak spot of Class-D.
It seems that Putzey finally figured something out.
"Granuarilty in sound" , as outlined in the report, can have a lot more causes though.
To list one more:
On Mundorf home you'll find measurements what vibrations on coils do to the signal/sound.
You IMO can add big caps to that list as well.
Once more. What I really consider a weak spot on the Purifi amp is the lack of vibration dampening.
After more time listening to the amp by now, I still can't say, I'm fallen in love with the Purifi amp.
Enjoy.
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VERY interesting. However, I am not too keen in doing such surgery to my Purifi amps, they are splendid as they are...
Well, my build is about 9 Kg, top and bottom lids are 3mm aluminium dampened with two layers of alubutyl each, and the feet are sorbothane, so I am not worried about vibrations.
My Build
Here is my Purifi build, some details:
Custom linear supply for +/- 18 VDC to the input stage and modulators
WBT 0708 binding posts
Neutrik XLRs
I have been too busy enjoying the sound to wire up my standby switch yet, hence the blue nAmpon wire just tied to ground. I'll get around to it eventually.
Here is my Purifi build, some details:
Custom linear supply for +/- 18 VDC to the input stage and modulators
WBT 0708 binding posts
Neutrik XLRs
I have been too busy enjoying the sound to wire up my standby switch yet, hence the blue nAmpon wire just tied to ground. I'll get around to it eventually.
Attachments
Another Purifi amp build - in Audio Research chassis
Here's my Purifi amp build using a vintage Audio Research chassis. Details here:
Purifi Amplifier Project
Mike
Here's my Purifi amp build using a vintage Audio Research chassis. Details here:
Purifi Amplifier Project
Mike
Attachments
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barrows, mikebarney,
Very neat builds, congrats to both of you!
Once you spend more time listening, do tell us about your impressions. Also please share a bit about your system and what amplifier the Eigentakt is expected to replace/dethrone.
Have fun listening!
p.s. mikebarney, visited your website where you've documented your build - well done and should be helpful for other folks.
Very neat builds, congrats to both of you!
Once you spend more time listening, do tell us about your impressions. Also please share a bit about your system and what amplifier the Eigentakt is expected to replace/dethrone.
Have fun listening!
p.s. mikebarney, visited your website where you've documented your build - well done and should be helpful for other folks.
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NC-400
My prior main amp was a DIY NC-400. I have also had the Merrill Audio veritas twins (2x NC-1200) and a friends NC-500 Nord amp, with the rev 3 input boards in my system.
VS the NC-400 it is close, but there are meaningful differences, slightly more detail, a little more body and more natural sounding.
My NC-400 beat out my prior Pass Labs amp...
My prior main amp was a DIY NC-400. I have also had the Merrill Audio veritas twins (2x NC-1200) and a friends NC-500 Nord amp, with the rev 3 input boards in my system.
VS the NC-400 it is close, but there are meaningful differences, slightly more detail, a little more body and more natural sounding.
My NC-400 beat out my prior Pass Labs amp...
Actually...
I work in high end audio for Sonore. This chassis was obtained from the chassis supplier we have build our chassis for Sonore Signature Rendu SEoptical. It is not actually available to DIYers in general.
I work in high end audio for Sonore. This chassis was obtained from the chassis supplier we have build our chassis for Sonore Signature Rendu SEoptical. It is not actually available to DIYers in general.
Huh?
I was answering a question about where I obtained my chassis. I do not even know what a "high end" belief system is??? And what does this have to do with the DIY Purfif amplifiers we are talking about here? Let's not take the thread off topic. I come to DIYaudio to learn and share DIY audio experiences, not to discuss my work in audio. If you would like to make any further communication on this topic, please feel free to do so by PM.
I have no commercial interest in the Purifi company, or its products at this time. I also paid full retail for the modules.
I was answering a question about where I obtained my chassis. I do not even know what a "high end" belief system is??? And what does this have to do with the DIY Purfif amplifiers we are talking about here? Let's not take the thread off topic. I come to DIYaudio to learn and share DIY audio experiences, not to discuss my work in audio. If you would like to make any further communication on this topic, please feel free to do so by PM.
I have no commercial interest in the Purifi company, or its products at this time. I also paid full retail for the modules.
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Ummm...
I prefer the Purifi to the NC-400, yes.
Vs. NC-1200, that is a different question as the comparison is apples to oranges given the different power output. I suspect that kind of comparison would have more to do with the reqiuirements of the speakers involved.
For a comparison from NC-1200 to Purifi, I think it would be best to wait for the Purifi "800" modules, with closer power output to the NC-1200.
Bruno Putzeys has mentioned that the long time plan for Purif includes scaled up modules with 2x the power output of the current "400" modules.
I prefer the Purifi to the NC-400, yes.
Vs. NC-1200, that is a different question as the comparison is apples to oranges given the different power output. I suspect that kind of comparison would have more to do with the reqiuirements of the speakers involved.
For a comparison from NC-1200 to Purifi, I think it would be best to wait for the Purifi "800" modules, with closer power output to the NC-1200.
Bruno Putzeys has mentioned that the long time plan for Purif includes scaled up modules with 2x the power output of the current "400" modules.
thanks for your opinion. My friend just built one last week His initiate impression is, purifi has power but lack of dynamic. Did u have such experience? Would it be better after burn in? He didnt use LPS for the buffer part. He just use the unregulated power from the same Hypex power supply.
One last question, when u imput LPS,do u need to switch the jumper or something? Purifi buffer has its own regulator
Ummm...
1. I perceive no problem with dynamics here with my build.
2. I do believe the amp has improved after about 200 hours of playing time.
3. My linear supply for the input stage and modulator section is set to +/- 18
VDC, so nothing needs to be changed on the Eval board to accommodate it.
Yes, the Purifi board has onboard discrete regulators which reduce the voltage
to the working voltage. Of course, two stages of voltage regulation are often
superior to just one as long as the regulators used in the first stage do not
impede current flow, my linear supply uses Belleson regulators which feature
extremely low output impedance, so no worries there.
1. I perceive no problem with dynamics here with my build.
2. I do believe the amp has improved after about 200 hours of playing time.
3. My linear supply for the input stage and modulator section is set to +/- 18
VDC, so nothing needs to be changed on the Eval board to accommodate it.
Yes, the Purifi board has onboard discrete regulators which reduce the voltage
to the working voltage. Of course, two stages of voltage regulation are often
superior to just one as long as the regulators used in the first stage do not
impede current flow, my linear supply uses Belleson regulators which feature
extremely low output impedance, so no worries there.
Purifi 1ET400A / Hypex NC500 Input Buffer
Purifi 1ET400A / Hypex NC500 Input Buffer – Neurochrome
[ This input buffer is intended for use with the Purifi 1ET400A and Hypex NC500 Class D amplifier modules.
Unlike other buffers, including the Purifi EVAL1 and the Hypex NC500 Evaluation Board, this Input Buffer will provide a differential output for the Class D amplifier, even if the input to the Buffer is single-ended. This ensures that even a single-ended source can drive the 1ET400A and NC500 to clipping, something the Purifi EVAL1, Hypex NC500 Evaluation Board, and many other input buffers cannot do. Many also report improvements in sound quality when the Purifi 1ET400A and Hypex NC500 are provided a differential input.
The buffer is a single-channel (mono) buffer, with the following features:
Purifi 1ET400A / Hypex NC500 Input Buffer – Neurochrome
[ This input buffer is intended for use with the Purifi 1ET400A and Hypex NC500 Class D amplifier modules.
Unlike other buffers, including the Purifi EVAL1 and the Hypex NC500 Evaluation Board, this Input Buffer will provide a differential output for the Class D amplifier, even if the input to the Buffer is single-ended. This ensures that even a single-ended source can drive the 1ET400A and NC500 to clipping, something the Purifi EVAL1, Hypex NC500 Evaluation Board, and many other input buffers cannot do. Many also report improvements in sound quality when the Purifi 1ET400A and Hypex NC500 are provided a differential input.
The buffer is a single-channel (mono) buffer, with the following features:
- Differential (balanced, XLR) input, which can easily be configured for single-ended (unbalanced, RCA) operation as well.
- True differential output with common-mode feedback, which ensures a differential output, even when used with a single-ended source.
- Jumper-selectable gain: 0 dB and 13.2 dB for a total amplifier gain of 12.8 dB and 26.0 dB, respectively, when used with the Purifi 1ET400A.
- Gain can be further customized by adding a resistor (1206 size SMD and leaded/PTH supported).
- Plug-and-play connection with Hypex SMPS1200 and future Purifi power supply.
- Opamp power supply: Use the AUX supply provided by the SMPS1200, or add your own regulator. A small daughterboard with support for the Hypex HPR/HNR, LM7812/LM7912, and LM78L12/LM79L12 is available as a product option.
- Status indicator LED output (NC500: CLIP and READY; 1ET400A: READY).
- Speaker output is provided both on 6.3 × 0.81 mm quick-connect spades and a terminal block accepting up to AWG 10 (5.2 mm2) in size.
- The buffer can be disabled by removing two resistors. A three-pin connector footprint provides direct access to the Purifi 1ET400A / Hypex NC500 input.
- A two-pin connector footprint provides access to the remote sensing pins of the Purifi 1ET400A / Hypex NC500. ]
Purifi 1ET400A / Hypex NC500 Input Buffer
Purifi 1ET400A / Hypex NC500 Input Buffer – Neurochrome
[ This input buffer is intended for use with the Purifi 1ET400A and Hypex NC500 Class D amplifier modules.
Unlike other buffers, including the Purifi EVAL1 and the Hypex NC500 Evaluation Board, this Input Buffer will provide a differential output for the Class D amplifier, even if the input to the Buffer is single-ended. This ensures that even a single-ended source can drive the 1ET400A and NC500 to clipping, something the Purifi EVAL1, Hypex NC500 Evaluation Board, and many other input buffers cannot do. Many also report improvements in sound quality when the Purifi 1ET400A and Hypex NC500 are provided a differential input.
The buffer is a single-channel (mono) buffer, with the following features:
In addition, the following options are provided for advanced users:
- Differential (balanced, XLR) input, which can easily be configured for single-ended (unbalanced, RCA) operation as well.
- True differential output with common-mode feedback, which ensures a differential output, even when used with a single-ended source.
- Jumper-selectable gain: 0 dB and 13.2 dB for a total amplifier gain of 12.8 dB and 26.0 dB, respectively, when used with the Purifi 1ET400A.
- Gain can be further customized by adding a resistor (1206 size SMD and leaded/PTH supported).
- Plug-and-play connection with Hypex SMPS1200 and future Purifi power supply.
- Opamp power supply: Use the AUX supply provided by the SMPS1200, or add your own regulator. A small daughterboard with support for the Hypex HPR/HNR, LM7812/LM7912, and LM78L12/LM79L12 is available as a product option.
- Status indicator LED output (NC500: CLIP and READY; 1ET400A: READY).
- Speaker output is provided both on 6.3 × 0.81 mm quick-connect spades and a terminal block accepting up to AWG 10 (5.2 mm2) in size.
- The buffer can be disabled by removing two resistors. A three-pin connector footprint provides direct access to the Purifi 1ET400A / Hypex NC500 input.
- A two-pin connector footprint provides access to the remote sensing pins of the Purifi 1ET400A / Hypex NC500. ]
smps1200 has only one power socket. Do we need two 1200? They should also give us an special cable which can share the same smps1200
Hi all, I'm new here on this forum and on the verge of building my very first amplifier using these Purifi modules along with the SMPS1200A400 power supply.
I'm reasonably technical, but this is my first time dealing with electronics and I don't have an electronics background.
In my build I would like to add a push button to the front of my case to toggle between standby/on, as well as a 12V trigger input to the back for integration into the rest of my system.
I had emailed Hypex about their soft start module (which would have made integrating a front switch pretty easy) and they said that module doesn't support 12V triggers.
So a few questions:
1. Is a soft start module with inrush current protection really necessary?
2. If yes to 1, does anyone know of a way to integrate a 12V trigger with such a module?
3. If no to 1, what is a good and relatively easy way for a beginner like me to build in a front push-button and 12V trigger? All I know at this point is that I'd need another 12V power supply for the trigger functionality.
Thanks!
I'm reasonably technical, but this is my first time dealing with electronics and I don't have an electronics background.
In my build I would like to add a push button to the front of my case to toggle between standby/on, as well as a 12V trigger input to the back for integration into the rest of my system.
I had emailed Hypex about their soft start module (which would have made integrating a front switch pretty easy) and they said that module doesn't support 12V triggers.
So a few questions:
1. Is a soft start module with inrush current protection really necessary?
2. If yes to 1, does anyone know of a way to integrate a 12V trigger with such a module?
3. If no to 1, what is a good and relatively easy way for a beginner like me to build in a front push-button and 12V trigger? All I know at this point is that I'd need another 12V power supply for the trigger functionality.
Thanks!