Sorry posted in wrong section.
I am thinking of doing 3 mods to the torroid transformer in my amp but not sure if it will help.
1. Encase the tranformer in a steel casing to block the magnetic field.
2. Isolate the teansformer from the amp. Rest the transformer on a thick fiam pad so any mechanical hum is not transmitted to the chassis.
3. Fill the steel casing with non-conductive ferrofluid. I think this will help to cool the transformer. I am hoping it will perhaps improve the efficiency of the transformer as well.
I am thinking of doing 3 mods to the torroid transformer in my amp but not sure if it will help.
1. Encase the tranformer in a steel casing to block the magnetic field.
2. Isolate the teansformer from the amp. Rest the transformer on a thick fiam pad so any mechanical hum is not transmitted to the chassis.
3. Fill the steel casing with non-conductive ferrofluid. I think this will help to cool the transformer. I am hoping it will perhaps improve the efficiency of the transformer as well.
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No matter the section, the answer is no, not at all.
All cooling will do is somewhat compensate the DCR increase caused by overheating copper and keeping power supply voltages steadier, butb thermaltime constant of many kilograms of copper and iron is so long as not to have any influence on *audio*nsignals, so no change in quality.
Mind you, I DO cool my large Musical Instrument power transformers, go figure, it is the first object in front of the fan air flow , but it´s for the reason stated above, not sound quality.
All cooling will do is somewhat compensate the DCR increase caused by overheating copper and keeping power supply voltages steadier, butb thermaltime constant of many kilograms of copper and iron is so long as not to have any influence on *audio*nsignals, so no change in quality.
Mind you, I DO cool my large Musical Instrument power transformers, go figure, it is the first object in front of the fan air flow , but it´s for the reason stated above, not sound quality.
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So this guy is lying ?-
Audio Myth - "Switching Power Supplies are Noisy" - Benchmark Media Systems.
Audio Myth - "Switching Power Supplies are Noisy" - Benchmark Media Systems.
No, not lying, but if you have hum, it's a design issue, not a feature of a linear supply.
Speaking with my EMC Engineer hat on now...
A SMPS will almost certainly be cheaper where high power is required, which is why they're using marketeering to 'sell' the idea of it being somehow better to less informed audiophiles.
The measurement they made with the mag loop antenna is one I make regularly too. The linear supply will be quieter overall, but will probably have a big emission at the power fundamental, and maybe a couple of harmonics thereof, as *might* the SMPS. The SMPS will have far more noise at the switching frequency and far more harmonics. This is why they say you can stack *audio* equipment above it. Anything operating in the hundreds of kHz / low MHz area may be affected by it. Interesting that they stated they made measurements, but didn't show the results 😉
Horses for courses. Low power, linear wins. High power these days, SMPS.
Speaking with my EMC Engineer hat on now...
A SMPS will almost certainly be cheaper where high power is required, which is why they're using marketeering to 'sell' the idea of it being somehow better to less informed audiophiles.
The measurement they made with the mag loop antenna is one I make regularly too. The linear supply will be quieter overall, but will probably have a big emission at the power fundamental, and maybe a couple of harmonics thereof, as *might* the SMPS. The SMPS will have far more noise at the switching frequency and far more harmonics. This is why they say you can stack *audio* equipment above it. Anything operating in the hundreds of kHz / low MHz area may be affected by it. Interesting that they stated they made measurements, but didn't show the results 😉
Horses for courses. Low power, linear wins. High power these days, SMPS.
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I build monoblock power amps in class A with outboard power supplies
Apache and have no trouble with radiated noise of any frequency.
I got into a lot of trouble in EW when I stated ---quote- "I prefer linear power supplies" some guys had their businesses to protect.
Thats why I posted in a round about way.
Apache and have no trouble with radiated noise of any frequency.
I got into a lot of trouble in EW when I stated ---quote- "I prefer linear power supplies" some guys had their businesses to protect.
Thats why I posted in a round about way.
A linear PSU will normally exhibit a much lower impedance to the amplifier than an SMPS design.
This on its own will generally make a linear PSU a better choice.
However, if you correctly design an SMPS supply to be a low impedance supply with adequate HF isolation and filtering, there is no reason why an SMPS supply cannot work just as well.
Most SMPS designs are built around high switching frequencies. Keep these away from the amplifier.
SMPS designs also use much smaller value reservoir capacitors. These are fine for the PSU but aren't so good for the audio frequencies of the amp.
This on its own will generally make a linear PSU a better choice.
However, if you correctly design an SMPS supply to be a low impedance supply with adequate HF isolation and filtering, there is no reason why an SMPS supply cannot work just as well.
Most SMPS designs are built around high switching frequencies. Keep these away from the amplifier.
SMPS designs also use much smaller value reservoir capacitors. These are fine for the PSU but aren't so good for the audio frequencies of the amp.
Duncan2 - know where you're coming from. For high power amplifiers, SMPS (and associated Class D topology) allow high power outputs for not much money in the pro audio world, OR much greater profit margin in the domestic high end world.
KatieandDad, indeed, there shouldn't be a problem in terms of noise at audio frequencies (unless you have one of those crazy things with no bandwidth definition, then you'll be wondering why everythings so hot 😉 )
However, in my experience it's rare to find one (outside of military spec ones with a couple more zeros on the price) that doesn't exhibit very high radiated emissions at and well above the switching fundamental.
KatieandDad, indeed, there shouldn't be a problem in terms of noise at audio frequencies (unless you have one of those crazy things with no bandwidth definition, then you'll be wondering why everythings so hot 😉 )
However, in my experience it's rare to find one (outside of military spec ones with a couple more zeros on the price) that doesn't exhibit very high radiated emissions at and well above the switching fundamental.
The noise often finds its way onto the casework, and because on the much higher frequencies, a ground isn't always a ground so the case itself radiates. Best way of bonding them is not via a bit of green / yellow sheathed wire, but with full contact to a ground plane.
We generally aim for <2.5 milliohm ground resistance. As others have said, not a problem for audio, but might be for those around you!
We generally aim for <2.5 milliohm ground resistance. As others have said, not a problem for audio, but might be for those around you!