YY -- do not lump all power devices into the same category. There are basically 4 kinds of devices:
1. Regenerators
2. Conditioners
3. Isolation transformers
4. Balanced power units
The first device to try is really not a device: dedicated circuit(s) with or without isolation (transformers)
1.) REGENERATORS: If you can't install DCs for some reason, the next best thing is a power regenerator. Basically a PR takes wall current -- dirty, noisy, fluctuating, inaccurate wall power -- and "re-manufactures" it into perfect, theoretically ideal AC power. The best (most electrically efficient) one currently on the market IMO is the ExactPower EP-15A.
2.) CONDITIONERS: Power conditioner/surge protector units, including a very well respected one named after one of the Greek Furies, are basically an assemblage of chokes and other filters plus some fast acting diodes. They can filter and cancel most line noise, but they do not improve the quality of the wall AC itself, and they do not offer meaningful protection against voltage spikes. The internal components they use can greatly slow down energy transfer (especially important for amps) rendering even the biggest power cords useless. I totally pass on these devices, and so should everyone (in my ever-so-humble opinion!)
3.) ISO TRANSFORMERS: These can be used with regular wall AC, dedicated circuits, regnerators or balanced power units. They are most often found with dedicated circuits and no other devices. They offer excellent protection from ground spikes (lightening) line noise and some powerline irregularities. They need to be large capacity to work with big amps, and can be expensive, but seem to be most popular with audiophiles who are also electrical engineers -- they must know something ;--)
4.) Balanced power units are an excellent way to provide quiet -- really quiet! -- power to source components. They represent a "finishing touch" after you have done dedicated circuits and/or 1 or 3. They usually do not improve amplifier performance, so buying one with sufficient capacity to handle an amplifier is not cost-efficient.
Your electronics and speakers are a nice combo, regardless of what other ppl use. If you ever have the chance to score/upgrade to a 26s and/or a 27.5 or 23.5 do it, and keep the speakers.
The 390S is in the top ten. It's not in the top three, but would have good synergy with your 26 -- use the balanced interconnects with it -- either Madrigal CZ GEL or PAD Venustas. Also use balanced PAD Venustas ICs between the 26 and 27 and for the spkr cables.
Get rid of the cheap power conditioner but don't spend money on an expensive one! If dedicated circuits can be installed DO IT before spending money on ANY power devices. If they can't be installed, then get an EP-15A and plug everything into it. That may be all you ever need.
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