You obviously never have tried.
Shortest test in the world. Please try it and you are welcome to join our club. We have the best drinks, the coolest chicks, sweet music played on good equipment and we’ll arrange some pot for you. How about that?!
Shortest test in the world. Please try it and you are welcome to join our club. We have the best drinks, the coolest chicks, sweet music played on good equipment and we’ll arrange some pot for you. How about that?!
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Oh I've tried. Many times...
My current preamp uses an ATX and several DC-DC converters to power my preamp/phono. No more damned hum.
FWIW I use a linear regulator on the DC-DC output. Best of both worlds 🙂
I'm drinking a Heineken while my mate plays a video game, I have good equipment, and I have good pot here, too 🙂 If you're ever in Toronto, you can come visit 🙂
My current preamp uses an ATX and several DC-DC converters to power my preamp/phono. No more damned hum.
FWIW I use a linear regulator on the DC-DC output. Best of both worlds 🙂
I'm drinking a Heineken while my mate plays a video game, I have good equipment, and I have good pot here, too 🙂 If you're ever in Toronto, you can come visit 🙂
It would require smuggling a linear PSU in my suitcase.
Oh oh a linear regulator at the output of an SMPS. That is cheating in a way.
Oh oh a linear regulator at the output of an SMPS. That is cheating in a way.
What if I told you I have a tube system that has a full preamp, 30W-120W triode power, and can run from a car battery? 🙂
A more practical version would be the RIAA preamp that can also run on a car battery though. Cheating or smart? I didn't know there were rules to cheat against LOL
Still... No damned hum 🙂
A more practical version would be the RIAA preamp that can also run on a car battery though. Cheating or smart? I didn't know there were rules to cheat against LOL
Still... No damned hum 🙂
This is nonsense. Reliability of electronics is directly related to heat.
A temperature increase of 10 degrees C is generally accepted as cutting the life of a device in half. There are many web pages and engineering texts that explore the impact of temperature on MTBF.
Linear supplies run much hotter than SMPSs.
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The meanwell smps in my pre amp have a claimed MTBF of 80 years. Im OK with that.
There is more to that. Industrial linear power supplies run hot at a certain spot, often being the heatsink with the regulating part and the rectifiers. SMPS are smaller and all parts are hotter overall combined with many switching actions/pulses. If one repairs stuff one must have seen bulged caps in SMPS.
That 80 years MTBF is a fairy tale. When one repair stuff on DIY or professional basis one sees a thing here and there and the weakest point in audio devices with SMPS is that SMPS in many cases.
In real life very cheap adapters are delivered with various equipment that sometimes already fail within the warranty period. This discussion is going to and forth but normal equipment below 500 Euro won't have the best of SMPS in general. The low cost category is very popular and those wall warts have a reputation that is confirmed by many. I forgot the exact number but I think it is that 2 families of 4 die every month here because of phone chargers and wall warts being plugged in at night causing a fire.
Personally I have serviced heart operation equipment and the SMPS used were quite good (never had 1 failing!) so my new Linn amplifier with SMPS will be just as good. You see what I mean? OK now ask a Linn owner what he/she thinks of SMPS.
That 80 years MTBF is a fairy tale. When one repair stuff on DIY or professional basis one sees a thing here and there and the weakest point in audio devices with SMPS is that SMPS in many cases.
In real life very cheap adapters are delivered with various equipment that sometimes already fail within the warranty period. This discussion is going to and forth but normal equipment below 500 Euro won't have the best of SMPS in general. The low cost category is very popular and those wall warts have a reputation that is confirmed by many. I forgot the exact number but I think it is that 2 families of 4 die every month here because of phone chargers and wall warts being plugged in at night causing a fire.
Personally I have serviced heart operation equipment and the SMPS used were quite good (never had 1 failing!) so my new Linn amplifier with SMPS will be just as good. You see what I mean? OK now ask a Linn owner what he/she thinks of SMPS.
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Of course but in most cases the failure of SMPS is because of capacitors lose their properties over time. Do you have any solution for this?
But the failure rate is very low compared to SMPS! I guess its because of transformers has much heavier thermal mass, bigger exposed surface area & most of the time attached to metal chasis. More importantly capacitors lasts longer in linear psu....
https://www.eevblog.com/forum/chat/capacitors-on-switching-power-supply-vs-linear-power-supply/
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That's alright with me. I was just trying to share my experience working in a high reliabilty industrial electronics repair facility for 33 years. I've fixed thousands of linear supplies in that time and many hundreds of SMPSs, despite there being more SMPSs on that site than linear supplies. You are welcome to take that experience with a grain of salt. Perhaps your experience with industrial electronics differs from mine.
For what it's worth I think SMPS wall warts and ultra low cost consumer supplies are rubbish.
For what it's worth I think SMPS wall warts and ultra low cost consumer supplies are rubbish.
Possibly the “tech issue” comes to play. Example:
1 million linear PSUs are used in some devices. Then a series of 100000 is produced with SMPS.
The linear version has 5% failure in 5 years and the SMPS 20%.
What do you think repairmen will think of the linear version?
1 million linear PSUs are used in some devices. Then a series of 100000 is produced with SMPS.
The linear version has 5% failure in 5 years and the SMPS 20%.
What do you think repairmen will think of the linear version?
Agreed 🙂 Industrial, medical and military stuff are playing in another league.
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I am using one to power to power bi-amped JLH class A amplifiers, and it is amazing. The psrr of that design isn't brilliant, and with linear power supplies I can always hear a hum. The preamp uses a linear power supply, that is a Doug Self design, with a phono stage from his earlier design. I am definitely happy with it. I still try to upgrade the setup, but haven't heard any improvements with various changes (That may be due to my age, but I can still hear high notes!)
That is one of the best examples where an SMPS outperforms a linear PSU but that is because it is a class A amplifier. I also used 24V SMPS for JLH with outstanding results and no hum or ripple.
Now imagine that 5 mV sensitive phono preamp with a 50 mV noise/ripple wall wart SMPS.
Now imagine that 5 mV sensitive phono preamp with a 50 mV noise/ripple wall wart SMPS.
Fully agreed. The elephant in the room is not SMPS per se - but the wordlwide system of al cheapo stuff beeing the most successfull selling. If we would decide to design - and buy!!! - long life stuff - smps would be no longer disdadvantageous. The failure rate is most of the time a matter of internal hot spots - due to ultra-compact design as well as ultra-cheap components. There exist solutions...
my 2 c
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The caps first failing are the secondary bulk caps that are heavily stressed by ac-current in a typical 5V-flyback-charger. More often than not you will find something like 1000uF/6.3V - tiny things underrated for high current ripple demand with an ESR in the range of 1Ohm after some time of usage. Keep in mind that ac-ripple current easyly exceeds 1amp rms under load conditions. And ESR of electrolytic caps is a matter of size. Replace by 470uF/35V and the problem is fixed.
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