I was saying that the only reason it *would* make a difference to sound would be if it was defective in some way. I doubt that would occur in practice.
If one wants to make a linear psu for the purifi amp, then that's a personal preference. But I wouldn't bother doing so because you think it's going to sound any different !
I would only do it for the sake of long-term reliability. I don't think SMPS last that long. I'm already seeing failing caps on my Hypex SMPS600N400 - they run very hot. Meanwhile, linear PSUs in amps I have that are 40 years old are still going strong.
Yet, over time, the energy usage of the linear PSU will be far greater - bad for the earth - and will cost more to run. Therefore, overall, the SMPS comes out the best option, even with the odd cap replacement every 5 years.
* Because they will sound the same *
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That's very debatable.
SMPS are more complex; cap failure might damage the SMPS so replacement would not help.
When linear power supplies last long (my 30 years old humble Rotel power amp still has it's 15kuF electrolytics and show now leakage), and SMPS would require cap replacement on a regular basis, my choice would be simple.
If efficiency is of the outmost importance, listening to music on any loudspeaker is a good way to waste energy since most loudspeakers are terrible in terms of converting electrical signals to mechanical motion. We are looking at a few percentage and of that, only 50% is useful since half of the acoustic output is not used. A linear PSU is hugely efficient (50-60%) compared to the loudspeaker. As we (humans) move over to more and more reusable energy delivery systems, waste becomes less and less of a concern. So am I worried about the consumption, no not really. And besides, I don't listen at 100+dB for hours on end, some do yes, but not me. A debate about energy consumption is a slippery slope and at one point we will probably end up at "stop listening to music"
I do notice that most, not all, agree that linear is a safer bet than a SMPS. While SMPS has its clear advantages, it is also clear that when it comes to the electric quality and while it has approved, there seem to be SMPS issues that still need to be dealt with. I am not an engineer so I am not going to propose any solutions, but what I can do is weigh the advantage and disadvantage of both PSU variants.
Like mocenigo pointed out, a capacitance multiplier is a good way to reduce any ripple and noise. While SMPS has developed since the late 1950's and efficiency and overall quality has steadily increased, I'm not convinced that for audio, it is the best option.
Let me put it this way. The amount of heated argument and "hate" towards each members view of which SMPS should be used is in itself an indicator and in order to have a chance to know if the SMPS of choice is any good, you first need to become a proper engineer.
I don't advocate any specific PSU, that is not my role. My role for myself is to make a choice I know will work in the long run and if that mean "older tech" then so bit it... I guess
If that's how your discussions go, then that is absolutely your problem.. I dont have that problem. I am able to have a discussion about power supply choices without going to the ridiculous. I'm sorry you have trouble with focus. Anyway, your daft argument is flawed - the more efficient power supply also reduces absolute losses via the speakers. Simple multiplication.
The basic facts are:
SMPS and linear with Hypex/Purifi sound the same. So there is no choice to be made on sonic grounds.
SMPS are ready-made, off-the-shelf components that provide everything you need to get the amp running perfectly. They are efficient so they are good for lowering your energy usage (whilst still doing what you love) and lowering energy costs.
Linear PSUs can be far more expensive to build, time consuming to build and source components for, are less energy efficient and cost more to run.
SMPS *may* need occasional, easy and cheap repairs, linear likely not. But those repairs over a life-time are likely less time consuming than the total build of the linear PSU in the first place.
Given you're currently looking to replace whatever current amps you have - you haven't decided to stick with an amp with linear PSU for decades - your usage of the amp will probably be restricted to a few years anyway, so aspects of long-term reliability aren't that great a consideration.
As you are not an engineer, perhaps you're better off with the SMPS then? No knowledge needed.
The basic facts are:
SMPS and linear with Hypex/Purifi sound the same. So there is no choice to be made on sonic grounds.
SMPS are ready-made, off-the-shelf components that provide everything you need to get the amp running perfectly. They are efficient so they are good for lowering your energy usage (whilst still doing what you love) and lowering energy costs.
Linear PSUs can be far more expensive to build, time consuming to build and source components for, are less energy efficient and cost more to run.
SMPS *may* need occasional, easy and cheap repairs, linear likely not. But those repairs over a life-time are likely less time consuming than the total build of the linear PSU in the first place.
Given you're currently looking to replace whatever current amps you have - you haven't decided to stick with an amp with linear PSU for decades - your usage of the amp will probably be restricted to a few years anyway, so aspects of long-term reliability aren't that great a consideration.
As you are not an engineer, perhaps you're better off with the SMPS then? No knowledge needed.
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I may stand corrected. The NC500 is in my opinion a stunning amplifier, but in comparison to the 1ET400A it has one big advantage (more power) and one disadvantage which is difficult too evaluate (the eigentakt treble is much smoother, and the bass is a bit better controlled). Two fine amps, but on sound quality the eigentakt is better, or with some abuse of words, the NC500 has some treble flaws.
If efficiency is of the outmost importance, listening to music on any loudspeaker is a good way to waste energy since most loudspeakers are terrible in terms of converting electrical signals to mechanical motion. We are looking at a few percentage and of that, only 50% is useful since half of the acoustic output is not used. A linear PSU is hugely efficient (50-60%) compared to the loudspeaker. As we (humans) move over to more and more reusable energy delivery systems, waste becomes less and less of a concern. So am I worried about the consumption, no not really. And besides, I don't listen at 100+dB for hours on end, some do yes, but not me. A debate about energy consumption is a slippery slope and at one point we will probably end up at "stop listening to music"
Ultimately putting sound in the room is waste of energy as only your ears need that sound pressure. The reason why headphones are so popular is claimed to be portability but it is the energy saving aspect which has the most significant global impact
But on the other side being in an open sound field is what our auditory system evolved to.
In general I agree that most what is called "High End Audio" is monstrous loudspeakers with low efficiency compensated with high powered amplifiers. I would be interested if Purifi comes out with a lower powered version and a perfect SMPS.
As I build my own drivers I am trying to increase their efficiency but being bending wave drivers that more limited than other technologies but at least I am not using a conventional x-over which waste as much energy as the drivers do.
Curious...
I am curious as to why you would really want a lower powered option from Purifi? After all, the efficiencies involved with their current offering do not use hardly any power while idling, so the power use at lower output powers will still be very, very low. I just do not see that there would be any advantage to a model with lower output power? If you do not need the full power available from the present design, you can power it with a smaller SMPS to save a little more energy there, but still we are getting into the area of diminishing returns here. And, the 1 watt performance is fantastic, so it will sound very, very good powering an efficient speaker system. After all we are not talking about class A or A/B here with high idling current consumption.
Ultimately putting sound in the room is waste of energy as only your ears need that sound pressure. The reason why headphones are so popular is claimed to be portability but it is the energy saving aspect which has the most significant global impact
But on the other side being in an open sound field is what our auditory system evolved to.
In general I agree that most what is called "High End Audio" is monstrous loudspeakers with low efficiency compensated with high powered amplifiers. I would be interested if Purifi comes out with a lower powered version and a perfect SMPS.
As I build my own drivers I am trying to increase their efficiency but being bending wave drivers that more limited than other technologies but at least I am not using a conventional x-over which waste as much energy as the drivers do.
I am curious as to why you would really want a lower powered option from Purifi? After all, the efficiencies involved with their current offering do not use hardly any power while idling, so the power use at lower output powers will still be very, very low. I just do not see that there would be any advantage to a model with lower output power? If you do not need the full power available from the present design, you can power it with a smaller SMPS to save a little more energy there, but still we are getting into the area of diminishing returns here. And, the 1 watt performance is fantastic, so it will sound very, very good powering an efficient speaker system. After all we are not talking about class A or A/B here with high idling current consumption.
If efficiency is of the outmost importance, listening to music on any loudspeaker is a good way to waste energy since most loudspeakers are terrible in terms of converting electrical signals to mechanical motion. We are looking at a few percentage and of that, only 50% is useful since half of the acoustic output is not used. A linear PSU is hugely efficient (50-60%) compared to the loudspeaker. As we (humans) move over to more and more reusable energy delivery systems, waste becomes less and less of a concern. So am I worried about the consumption, no not really. And besides, I don't listen at 100+dB for hours on end, some do yes, but not me. A debate about energy consumption is a slippery slope and at one point we will probably end up at "stop listening to music"
I contend that comparing the efficiency of a linear PSU to a loudspeaker is a red herring. They are not supposed to be compared ones to other, but, rather, PSUs should be compared to PSUs and loudspeakers to loudspeakers (or other transducing systems). They are also chained - the efficiencies multiply each other and therefore improving the power conversion efficiency of any stage in an audio reproduction chain by some factor will improve the efficiency of the whole system by that factor.
Even if only 1% of the energy sent by an amplifier to a typical home loudspeaker is converted to acoustic energy, moving from a 50% efficient linear PSU to a 95% efficient SMPS will still nearly halve the power consumption. I agree that we should to get completely crazy about this, or we would end up at "stop listening to music", but I believe in the green approach I followed by moving to Class D amps with SMPSs and efficient speakers (OTOH, I probably offset that for several years negatively in carbon footprint because of all the shipments).
The efficiency comment was more in general than being scientifically correct Imagine having this debate with does who use 211/845 SE pure class A amps and vintage speakers .. LOL. In general I do agree with you, an objective improvement like moving from linear to SMPS has to be considered a good thing, same with class ab to class d
Imagine having this debate with does who use 211/845 SE pure class A amps and vintage speakers .. LOL. In general I do agree with you, an objective improvement like moving from linear to SMPS has to be considered a good thing, same with class ab to class dThe efficiency comment was more in general than being scientifically correct
Well, some of the vintage speakers are pretty efficient, only with levels of distortion and, most importantly, nonlinearity in the frequency response that would make the distortion badly designed tube amps unnoticeable.
I am presently only using class D (Anaview) or class D/A hybrid (Devialet) so I am aware of their power consumption under various conditions but high output amps have their best performance at higher output levels and would a lower powered amp not have that at lower level (in a range one really listens to it)?
Considering...
"I am presently only using class D (Anaview) or class D/A hybrid (Devialet) so I am aware of their power consumption under various conditions but high output amps have their best performance at higher output levels and would a lower powered amp not have that at lower level (in a range one really listens to it)?"
I suggest that you take a look at the power vs. distortion+noise curves for the Purifi modules. At 1 watt into 8 ohms they have <.001%. I just do not see that there would be any real world (audible) advantage to making a lower power module. Sure, the levels drop even more at slightly higher output powers, but either way, the noise and distortions are at levels which most consider inaudible.
"I am presently only using class D (Anaview) or class D/A hybrid (Devialet) so I am aware of their power consumption under various conditions but high output amps have their best performance at higher output levels and would a lower powered amp not have that at lower level (in a range one really listens to it)?"
I suggest that you take a look at the power vs. distortion+noise curves for the Purifi modules. At 1 watt into 8 ohms they have <.001%. I just do not see that there would be any real world (audible) advantage to making a lower power module. Sure, the levels drop even more at slightly higher output powers, but either way, the noise and distortions are at levels which most consider inaudible.
ermmm... im very new to diy and came across this forum (please be patience with me)... i have a SMPS1200A700 using hypex ncore 500 board in apollon mono block. i wanted to change the hypex ncore 500 board to PURIFI 1ET400A board. can i just swap out like that? i saw that the PURIFI 1ET400A are using SMPS1200A400
This might be off topic but I really would appreciate some advice on matching the NC500 with either the SMPS1200A700 or the SMPS3KA700.
I am just curious for a stereo(2 channel) set up which one would be appropriate and would 1 power supply suffice for the 2 NC500 modules?
To be honest, how many channels can I put on either one, say could I put 4 channels on one power supply?
I am just curious for a stereo(2 channel) set up which one would be appropriate and would 1 power supply suffice for the 2 NC500 modules?
To be honest, how many channels can I put on either one, say could I put 4 channels on one power supply?
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