Any examples?
Are we talking about the same thing? To me it sounds like you are talking about integrating the DAC with the amp, instead of having a truly fully digital amplifier (where the signal never enters the analog domain (voltage or PWM) even internally).
Fair enough - I am pointing out why that subjective perception might not tell us much.
Lyngdorf to name one.
Nope. I'm talking about a full digital controller (offering all kind of inputs and DSP capabilities ) feeding a separate full digital power stage.
By making two devices out of it there might be a chance to address a wider market.
I brought that up because I was suggesting that Putzey doesn't want to limit the addressable market by going full-digital with a single product that'd include all kind of inputs.
Yes, they use "fully digital" as a marketing phrase, but is it really?
What is your definition of "full digital power stage"?
No, it has nothing to do with markets, and all to do with feedback theory.
Have you done the mathematical analysis of the effects of quantizing and delaying the feedback loop?
Lyngdorf can be considered one of the pioneers in the all-digital area with the Tact brand.
To be more specific: Have a look at the rather recent TDAI-3400. (Analog inputs are ADCed )
Even Putzey must have realized by now, after working with Lyngdorf, that a more holistic view by covering a system and not just a single device can change perspectives:
"finding the better compromise"
Meaning: If the issue identified by Putzey is much less of a problem than the potential upstream gains that come with a full digital amp, he'd have no arguments to keep his direction. Except - for marketing/commercial reasons.
And I do recall that Putzey had taken the position you're outlining during his Hypex times. Hypex focus was solely on analog input Class-D amps during these days. And that argument was and stil seems to be a killer argument
to shut all critics up.
The real issue by going HQ full digital: People get bored. Not much to change. Not much to tweak. And for the Pros: Not much to sell!
Back to Purifi!!!
To be more specific: Have a look at the rather recent TDAI-3400. (Analog inputs are ADCed )
Even Putzey must have realized by now, after working with Lyngdorf, that a more holistic view by covering a system and not just a single device can change perspectives:
"finding the better compromise"
Meaning: If the issue identified by Putzey is much less of a problem than the potential upstream gains that come with a full digital amp, he'd have no arguments to keep his direction. Except - for marketing/commercial reasons.
And I do recall that Putzey had taken the position you're outlining during his Hypex times. Hypex focus was solely on analog input Class-D amps during these days. And that argument was and stil seems to be a killer argument
to shut all critics up.
The real issue by going HQ full digital: People get bored. Not much to change. Not much to tweak. And for the Pros: Not much to sell!
Back to Purifi!!!
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I ask again - what is your definition of "all-digital"?
It is not simply "an issue" - it is a major hurdle, in a very fundamental way.
Again: Have you done the mathematical analysis of the effects of quantizing and delaying the feedback loop?
You can look the principle up. There's a nice tool called "google"
Please stop this nonsense. I think you very well understood what I am saying.
It simply doesn't matter if the overall audible result speaks for itself.
And coming back to the actual topic. Looking at what kind of pull ups (buffer stages / power supplies / pre- amps / DACs / streamers ...) people have to do
to get the Purifi (and most other analog amps) properly up 2 speed, I'd consider a well done full digital implementation well worth a try.
I am very familiar with the principle. I am asking for *your* definition. Feel free to use google...
It only becomes nonsense if you can't define the terms you use.
"If it sounds good, it is all digital, even if it isn't"
I suggest you go ahead and try then!And coming back to the actual topic. Looking at what kind of pull ups (buffer stages / power supplies / pre- amps / DACs / streamers ...) people have to do
to get the Purifi (and most other analog amps) properly up 2 speed, I'd consider a well done full digital implementation well worth a try.
I think the question here is: can we manufacture a power DAC? All attempts I am aware of have failed. The point here is that we cannot probably use a feedback loop because it would be too slow (need an ADC to convert back and compute the error). Then, high order oversampling and noise shaping — which needs the ability to switch very quickly, in the high MHz region. Silicon FETs are not suitable. Then GaN may come to the rescue. Which has however still more noise than Si. Maybe we will get there. Having a single analog step and everything else digital should be the holy grail – if attainable
Exactly. It is a major challenge, not just some inconvenience you avoid for marketing reasons.
Well the converters are 1-bit. So there is some additional processing after that. Also, they had demos in 2017, but no product yet for the market. Indeed, there are difficulties in this.
Not much, if anything at all, changed. I have to admit though the system wasn't playing much, maybe 15h, since last week.
However. Positive impressions prevail.
One thing of course I hadn't considered is that the Purifi and the Hypex SMPS can deliver much more power than my Anaview.
That already can make up for quite a difference.
I typically use Scheherazade-Reiner-Chicago_SO-Track4 as my orchestral test track.
A nice tape transfer from the 50s.
The Purifi paints the full stage nicely balanced in all directions (left/right, up/down, back/front).
Nope. My Anaview can't do that, presenting such a equally balanced and equally dynamic soundstage.
But again. My Anaview was also doing a pretty good job on that track.
A higher power spec could of course already make quite a difference on such a demanding piece.
One thing I need to analyze a bit further is my early impression that e.g. a Conga drum
sounds a bit like listening to the skin being played only. Somehow the body sound
of the instrument is almost gone. The sound that comes from the skin is very nice though.
A similar feeling I had with an acoustic guitar btw. , where the strings and the finger work
where nicely present but the guitar body sound didn't really show up.
But again. The sound balance is different with this amp. It's hard to tell for me if something is really right or wrong.
There's so much right with this amp that I usually forget analyzing each and every situation.
*******
A Q to others:
My amp and HYPEX PS is still mounted on wood. No case (yet).
Now. The whole setup is currently floating, NOT connected to GND/earth.
Just hooked up to phase an neutral.
I am wondering if this setup could face an issue or a weak spot by running it that
way???
THX
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