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Class D must read papers and publications

roog

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I have viewed a couple of YouTube interviews with Bruno Putzys but have yet to find a decent paper on his Purifi Eigentakt, anyone seen any decent explanation?

I could have sworn that I once found a link to the patent but haven’t been able to find this again.
 
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pma

pma

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roog

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Is it this one?

It might be, I recall seeing a fuzzy schematic showing his feed back loop, I’ll give it a read thanks for the link.
 

Sam Ash

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I tried Class D (N-Core module based) amps by ATI and really like them. Class D tech seems to be progressing positively. Has anyone come across, used or experienced amps made by a Spanish company called RAM Audio? They seem to have a good reputation and I think they build their own class D modules. Not sure how they compare to N-Core and Purifi. Anyone here have any idea about RAM Audio amps? especially the MDi range?
 

Killingbeans

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From what I can tell on the product pages, those RAM Audio amps are Class H? In other words Class AB amps with voltage rail trickery to make the efficiency much higher.

EDIT: Nevermind. I was looking at the Zetta. Not the Deneb or MDi.
 

Spkrdctr

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You are fighting a pointless fight at the Walmart headquarters in Deafenville. All amps, dacs and maybe speakers too sound the same to these deaf audio scientologists as soon as they start the el primo ABX tests. They will gleefully get their mass produced cheap Chinese smps boards primarily aimed at boosting manufacturer profit margins. These class D connoisseurs are the quintessential Walmart shopper: cheap, utilitarian and sterile.

So, save your breath and let them have their well deserved future.
Interesting view. What about the many great pioneers of audio who have made major strides in giving us better equipment and used blind tests to further the SOTA? I will say you did a fine job of using flowery words that would make any subjectivist proud. Words like Deafenville, scientologists, Walmart shoppers etc. Remember it has ALWAYS, 100% been the subjectivists who refuse any blind tests. Why would something that is supposedly easily heard by anyone all of a sudden be gone when a blind test is performed? It should at least make you wonder why.
 
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joeren

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Interesting view. What about the many great pioneers of audio who have made major strides in giving us better equipment and used blind tests to further the SOTA? I will say you did a fine job of using flowery words that would make any subjectivist proud. Words like Deafenville, scientologists, Walmart shoppers etc. Remember it has ALWAYS, 100% been the subjectivists who refuse any blind tests. Why would something that is supposedly easily heard by anyone all of a sudden gone when a blind test is performed? It should at least make you wonder why.
The best of class D is already performing as well class A amplifiers and will continue to improve with new designs using Gallium Nitride (GaN) power devices. GaN is capable of MHz switching frequencies and rise/fall times in the nanosecond, allowing 10s of nanosecond dead times. Technology and scientific deniers can keep their fingers in the dike with their eyes and ears closed as long as they like.
 

Sam Ash

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The best of class D is already performing as well class A amplifiers and will continue to improve with new designs using Gallium Nitride (GaN) power devices. GaN is capable of MHz switching frequencies and rise/fall times in the nanosecond, allowing 10s of nanosecond dead times. Technology and scientific deniers can keep their fingers in the dike with their eyes and ears closed as long as they like.

interesting. Can you explain GaN a bit more...
 

joeren

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interesting. Can you explain GaN a bit more...
Gallium Nitride (GaN) properties are quite different from silicon. Early on in the technology, devices made with GaN were depletion mode devices (on at zero gate voltage and needed a negative voltage to turn the device off). Enhancement (off at zero gate voltage) mode devices are now available. GaN’s advantage are smaller physical size for the same current and voltages as silicon, lower conduction losses, higher operating temperatures and much faster switching times, which reduces switching losses. Here’s a link to a company that produces GaN devices and modules. Two of my former colleagues currently work here.
 

Spkrdctr

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Gallium Nitride (GaN) properties are quite different from silicon. Early on in the technology, devices made with GaN were depletion mode devices (on at zero gate voltage and needed a negative voltage to turn the device off). Enhancement (off at zero gate voltage) mode devices are now available. GaN’s advantage are smaller physical size for the same current and voltages as silicon, lower conduction losses, higher operating temperatures and much faster switching times, which reduces switching losses. Here’s a link to a company that produces GaN devices and modules. Two of my former colleagues currently work here.
Wow, nice company. I checked out the website and it really brought me up to date. I'm only about 8 years behind the times. GaN is really taking over a lot of areas. It really is worth it. Best news today. Now I can drink my coffee and feel smug in knowing that the new kid on the block is taking over. I should have invested heavily in GaN. I missed the boat, again!
 
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joeren

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Wow, nice company. I checked out the website and it really brought me up to date. I'm only about 8 years behind the times. GaN is really taking over a lot of areas. It really is worth it. Best news today. Now I can drink my coffee and feel smug in knowing that the new kid on the block is taking over. I should have invested heavily in GaN. I missed the boat, again!
EPC is the front runner for GaN. There are many great videos on their website. My colleagues and I worked on some Government projects at GE Global Research but most were DOH projects with x-ray technologies.
 

Hipster Doofus

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Thank you for your wonderful post.

but, apparnetly in doing your research you have ignore the Bioregenrationcontigigous effects of vegetables and fungi,especially the root vegetables ability to communicate at levels far beyond the Audio Analysis. For measurements of this level you would need professional equipment like the VA 23HGD-2.4. Commonly known as the Vegi-Magic. This taps into the sub electron scale of giant mushrooms ability to send signals to other bio electric receptors which only recently have been discovered in Quantum -Gamaliel or black holes. These differences are audible in certain circumstances in which one consumes and becomes linked to forementioned mushrooms. In addition it is helpful to have one securely place ones tongue in ones cheek.


1673796011139.jpeg
1673796011139.jpeg
 

joeren

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Spkrdctr

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Thank you for your wonderful post.

but, apparnetly in doing your research you have ignore the Bioregenrationcontigigous effects of vegetables and fungi,especially the root vegetables ability to communicate at levels far beyond the Audio Analysis. For measurements of this level you would need professional equipment like the VA 23HGD-2.4. Commonly known as the Vegi-Magic. This taps into the sub electron scale of giant mushrooms ability to send signals to other bio electric receptors which only recently have been discovered in Quantum -Gamaliel or black holes. These differences are audible in certain circumstances in which one consumes and becomes linked to forementioned mushrooms. In addition it is helpful to have one securely place ones tongue in ones cheek.


View attachment 257280View attachment 257280
That looks like Amir testing his garden products! Amir is seeking the truth from his vegetables.
 

okok

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Gallium Nitride (GaN) power devices. GaN is capable of MHz switching frequencies and rise/fall times in the nanosecond, allowing 10s of nanosecond dead times.

thing is, any product out there actually done that? mhz? how many M, can do 500mhz? let alone GaN
 

joeren

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thing is, any product out there actually done that? mhz? how many M, can do 500mhz? let alone GaN
https://epc-co.com/epc/cn/gan技术杂谈/post/13752/gallium-nitride-brings-sound-quality-and-efficiency-to-class-d-audio
 

mdunjic

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Thanks to Amir, recently I have ditched my enjoyable and lovely sounding, but very hot running (especially during summer), Quad feed-forward ‘current dumping’ 909 power amp (still have it though), and am now biamping my Neat Acoustics Notive 1 speakers, using all class D power amp combo:

a) Buckeye 2-ch amp, based on Purifi 1ET400A board (in high gain, driving tweeter and midrange)
b) Audiophonics, Hyped nCore NC502MP 2-ch based amp (driving bass woofers) … pre-amp is Benchmark LA-4, DAC is SMSL Su-9n

According to Dylan from Buckeye, in high gain mode Purify 1ET400A based amp, perfectly matched with the voltage gain of Audiophonics nCore NC502MP based amp … Buckeye + Audiophonics combo really sounds great … he is definitely right

IMG_5988.jpeg



literally unlimited clean power per channel (500+ watts) for less than 2.5 Grands
 

Andysu

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behringer class d amplifiers
 
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