New 20 watt amp from Schitt Audio

[captainbeefheart]

2 hours ago, Pondoro said:

Well, he said they didn't comment and then he commented. But it does not surprise me that the manufacturers generally do not comment on these accessories. Why tick off the highest spending customers? I will say it for the manufacturers: if you buy a power cable to filter your power you are insulting the designer of the amp. 

 

Yes they never comment especially publicly not to alienate any of their potential customers, especially ones with deep pockets. Knowing I am an electrical engineer I think he wanted to save some face by saying what he said in a personal email. They send a power cable MORE than sufficient for the current draw of their devices which is the only thing to worry about, loss across the conductor which turns to heat, general rule of thumb for house wiring I believe was no more than 3% but that may have changed. For devices I am certain they keep it well under 1% which is much less of a voltage change vs the normal line fluctuations.

 

You mentioned filtering. IF a cable comes with some sort of filtering devices then it isn't the conductor doing anything to help, it is the filters which would be misleading saying "power cables make a difference" because well it really isn't the power cable doing anything it is the filters. Funny thing is people believe that the AC side filters are for the performance of the device but it isn't, the filtering that is important is AFTER the rectifiers because the rectifiers being highly non-linear loads will add distortion and ripple that needs to be filtered. We also filter for 120Hz noise being double the mains frequency from full wave rectifiers so they have a low impedance at 120Hz meaning any high frequency noise it will be a magnitude even lower impedance so rf gets filtered out. The REAL reason manufacturers place filters on the AC side of the power supply is to comply with FCC requirements to not pollute noise back into the power grid. This is why you see it mainly on computers, TV's etc..... that have switch mode power supplies which will highly pollute the grid if there weren't filters on the mains side. These usually comprise of Common mode chokes for common mode noise, Y caps across from each leg to ground for common mode noise, and X capacitors across the two legs for normal mode noise. Some also have normal mode chokes to further reduce normal mode noise.

 

If you really want to isolate your gear as much as possible from your house power then run a dedicated branch circuit for your gear, this cuts down on noise from other loads being on the same branch circuit propagating noise across inductance of the neutral leg. IF you live in an area where you power has lots of noise on it, usually this is if your house is the very first house on the branch from the pole transformer, many think if you are the last house, not true. The first house has everyone else after you propagating noise across the inductance of the line, you being closest to the transformer will see the most noise, so the house at the end of the line will make the most noise which is shown most on your house first in the line. IF this is you then you may want a dedicated filter device connected to the dedicated branch to power your sensitive gear. The power "conditioner" will have all the common mode and normal mode passive filters I mentioned. The absolute BEST way of filtering noise and sometimes more importantly distortion is to have ACTIVE power conditioners, these have been around in the industry for medical/Lab equipment that needs as clean a power as possible. They are also used in industries for power correction to keep losses and costs down. The active filtering and power correction is amazing compared to just passive filtering. I feel passive filtering is just fine for most our needs but if you the person that needs to have the best look into active power filters, they are expensive but are amazing at what they do.