Luxman m900u comes alive when not plugged into P20

I’m very concerned why my Luxman m900u has begun to really come alive after I decided to give the wall outlet a try. Prior to switching the cord from the P20 the sound I was getting-was good at best from the P20. Since I plugged it directly into a $3. Outlet, magic. Everything has increased even the power.
Luxman doesn’t use a standard ground system.
There’s no ground prong. I’m wondering if this has anything to do with the issues I’m having.

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Sorry I can’t answer your question but how do you like the Luxman?

Not a Luxman owner. I have a Pass 250.5. However, I stopped plugging my power amplification into power conditioners years ago. I have consistently found the life is sucked out of my power amp and I think it simply has to do with the sheer current draw a power amplifier wants. I don’t believe any claims of no current limitations made by any power conditioner manufacterer.
Source components, digital or analog, different matter entirely. Those components in my experience benefit. Note source components don’t draw anything like the kind of current a power amplifier with any decent oomph does.
Just my 2 cents. If your Luxman sounds great out of the wall, why fret? Sit back and enjoy!
Btw the power supply in most good power amps is way overbuilt. Manufacterers assume in design and testing the user will be operating off of an ordinary AC circuit.


Don’t be concerned. Not all amps like being plugged into a box first. And not all power boxes can handle or help all amps.

Be Happy.


The P20 is a power regenerator, designed to use with amplifiers.

It is an AC waveform regenerator. I use a Furman AC regenerator (a SPR 20i). A 20 amp unit. My comments apply to experience with an AC regeneration conditioner. Regeneration of a waveform should not be confused with power delivery or instantaneous overhead margin. I stand by my observations. I find good results with my source components. I do not find good results with my power amplifier. That applies to other power conditioners, not just the SPR 20i. hiendmmoe’s observations are what they are, happen to be similar to mine and simply show that he does not have an issue because his Luxman doesn’t do well with the P20.

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Actually, instantaneous overhead, is, exactly what PS Audio says, the P20 delivers.

(Grabs popcorn)


I can’t remember who posted this gif first In some other thread but it’s my favorite and I think it’s what @aangen was looking for



I believe that was @Elk

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Yes, a distant cousin.

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Kyle is correct. I agree that you made the correct decision to stop plugging your amps into powers conditioners. They raise the impedance and suck the life out of power amps. But a Power Plant is the exact opposite of a power conditioner. Instead of sucking
life it injects new life because it lowers impedance far beyond that which is available on the AC power line.

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The Furman is a voltage regulator, not a regnerator - at least as most of us think of these things. I expect it has plenty of instantaneous current reserves for a home system, as doe the P20.

I use a Furman regulator/conditioner in my location recording rack. It is a great unit and perfect for when one never knows what power will be like.

As already noted, not ever piece of kit is better plugged into another box first. And not all boxes are created equally.

Luxman are very popular with my Harbeth speaker supplier and he sells lots of them, and he probably wouldn’t know what a regenerator is if it landed on his foot (and he’s been selling hifi since 1974). I understand that this amplifier has a very sophisticated power supply and is very high power, so a regenerator may not be needed to fix anything.

My experience with regenerators, conditioners and cables is that there is no clear logic as to what does and doesn’t work, just go with what sounds better.

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My Chord mono blocks were plugged into wall sockets while my P10 was away getting fixed for 4 months, long story, so I got very used to the sound of them plugged into the wall sockets.
I got a big sound performance increase when my P10 returned and the amps were plugged into it.

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I don’t think you can generalise on all power conditioners in such a way. It is certainly not the case with the one I bought.
I bought it after a trial, never having previously known of the brand. I never read anything on their website before buying.
There are P20 users who put in these conditioners after regeneration.

Some say, that’s actually Elk.
I’m not saying. But some say.

I live in a 220V country. When I got my P12, I plugged all my gear into it and expected to be astounded. The opposite happened. It sounded lifeless, just like what the OP experienced. So I checked its settings. According to its LCD display, the P12 was regenerating 220V (its default setting) while my wall outlet was giving me 240V. Could this be it? I adjusted the P12 to match and holy cow! I heard the powerful and dynamic sound I was looking for. Additional tweaks via auto-tune and then manually adjusting multi wave and phase brought about further improvements.

This got me thinking. Perhaps the default output voltage of a regenerator should be as close as can be to the input voltage but not exceeding the standard variance?

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But Paul, he was using P20, and it was sucking the life out of his amp, so obviously P20 isn’t working in this situation. I always wondered HOW a power regenerator in the path of signal could possibly provide instantaneous high current during some music passages, it must by laws of physics change delay the current delivery.

The Power Plants all have current reserves to respond to sudden demands.

Amplifiers do this as well, in this case with capacitors.

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