Power Conditioning / Surge Protection

audio2design, Let's assume that amp draws from mains 1A during music peaks.  It will likely be drawn in spikes of amplitude reaching 10A.  If filtering coil has 1 ohm resistance it will cause voltage drop of 10V equivalent to 20% of max power loss.  In addition inductor in series supposed to filter out high frequency content (electrical noise) while normal current (narrow spikes) also has high frequency energy.  Of these two factors I would guess that inductive reactance of the coil will have bigger effect, unless inductor has high resistance (thin wire).  Such power loss might only limit maximum output peaks in well regulated amplifiers but might still be audible at any output power in less regulated amps (zero feedback etc.)

My amp has the same dynamics plugged into Furman or the wall.  Many people reported loss of dynamics with conditioners and that's the only plausible explanation I can come up with.

Why do you keep talking about noise and voltage spikes?
The problem is in narrow current spikes (pulses) charging capacitors that increase power losses on any impedance in series.

During orchestra forte voltage on power supply caps drops.  It is because of capacitor ESR, but also because of voltage drops on on transformer windings (copper losses) and any other impedance in series including power cord, house wiring, conditioner coil etc.  Simply, power supply is not load regulated (voltage vary with load).  Some unregulated supplies are better than the others often because they have oversized transformers.    Increasing capacitance should also help, but creates another problem - lower voltage ripple that results in much narrower and much higher charging current pulses, that will create even more power losses (including core losses for hysteresis and eddy currents because of high frequency content).

Capacitors charge in narrow current spikes, but they cannot charge to the same full voltage when there is voltage drop on impedance in series.

Perhaps spikes would be 1/12 less since we drop 10V of 120V.   It doesn't change anything.

I did not say more noise.  I believe that amplifier with less regulation will be less linear with changing power supply voltage.  Less linear = more distortions (like loss of dynamics).

You want to protect and to filter.  The problem is that filtering places resistance in series that causes big voltage drops and kills dynamics.  Most of power supplies take current from mains in short spike of huge amplitude (about 10 fold of average).  I use Furman Elite 20PFi.  They call it "Power Factor Correction", but in reality it is huge inductor in series with large capacitor (in parallel to load) that stores energy delivering up to 55A current for spikes (it presents resistive load to mains).  It also has very tight non-sacrificial over/under voltage protection with circuit breaker, that resets itself.

https://www.furmanpower.com/product/conditioner-power-ht-20a-power-factor-ELITE-20%20PF%20I

In addition, I installed whole house protection in form of dual 20A breaker (Siemens panel style), by just swapping breakers.  Even if you have to hire electrician it is worth it.  Today everything is electronic, including appliances and even bulbs.

Audio2design  I did not say that ripple current gets higher.  You argued that voltage on capacitor doesn't drop because charge time is higher.  I only stated that when charge time gets higher - ripple is higher (capacitor is charged from the bottom of the ripple to the next peak)

I only argue that at the moment when net capacitor current is zero (peak of the wave) voltage on capacitor depends on source voltage and source impedance.  That's the peak supply voltage for the output stage.  How much it will drop depends on total source impedance including house wiring, power cord, fuse, transformer windings resistance and added impedance of the filter in conditioner.   If this filter is poor then voltage drop, especially on inductive reactance, can be high.  Even if we assume only 10% it will result in 20% loss of max power - equivalent to about 6% of drop in perceived loudness.  I agree that in this case when amp is within 80% it should not be audible, but people claim it is.  Perhaps voltage drops even more.  Large linear supplies have a lot of filter capacitance reducing voltage ripple to very small resulting in even narrower and higher charging current pulses and much higher voltage drops on conditioner's filter impedance.  Many people report big loss of dynamics with some conditioners.

Unless the amp is voltage clipping you have not made a good argument for true loss of dynamics though the loss would not be much different than line voltage variation. That resistance limits the peak current but extends the charge time so I your 10A example the peak may drop to say 5A but charge time increases and the voltage drop becomes small overall.

This argument is nonsense.  Charge time increases because voltage ripple gets higher, but capacitor get charged to the lower voltage because of the voltage drop on additional impedance in series.  At the peak of the wave max voltage on capacitor is equal to source voltage (peak secondary voltage after rectifier) minus load current multiplied by the source impedance.  Adding any impedance in series lowers voltage on capacitor at the same output load.

We agree to disagree.

I'm just tired of arguing, especially most of people don't follow the subject.  I also don't understand some of your statements.  Capacitor is charged only from the bottom of the ripple to next peak.  Bigger ripple means longer charging time - ALWAYS!, but you disagree with this.

Ripple is a function of capacitance and load current.  At constant load current when capacitors get larger (big capacitance) voltage ripple gets smaller hence current charges will be narrower (and usually of higher amplitude because of lower ESR).  Yes, additional impedance will make charging pulses smaller, because they depend on source voltage divided by impedance in the charging circuit - but charging time will not get longer!  It will be charged exactly the same amount of time - from the bottom of the ripple to next peak. Additional impedance in the charging circuit will only result in the voltage drop and the lower voltage on capacitors. It does not affect charging time within each cycle.

Yes, Furman's output capacitor appears to be connected in parallel to electrolytic caps, but is not.  It is on the the other side of the rectifier on the AC side.  Voltage on this capacitor follows AC voltage cycle but any loss of charge caused by PS charging pulse is replenished from energy stored in the inductor thru the whole cycle.  In addition this (huge!) capacitor has very low ESR.  That way during narrow charging pulses current comes from this capacitor and not from the inductor.  Removing this capacitor would have huge effect on the amp.  Just connect big inductor in series with mains and you will see results.  There are power supplies that charge/discharge capacitors during whole cycle because they have big choke in series but then capacitors' voltage is an average and not the peak of the waveform.

Perhaps we're hijacking this thread?

Charging pulse starts at the bottom of the ripple and ends at the peak of the waveform.  When ripple is larger this time gets longer.  When you comprehend this we can go forward.

Amount of ripple depends on capacitance and load current and does not depend how capacitor is charged since ripple is an effect of voltage drop during capacitor discharge cycle hence has nothing to do with capacitor charging.  The way capacitor is charged will affect voltage on capacitor but ripple will be always the same percentage of this voltage.  When you comprehend this we can go forward.

The ESR of the film capacitor is almost meaningless as it does not charge the capacitors of the amplifier.

ESR is very important since any ESR in the charging circuit will limit maksimum voltage on capacitor.  When you comprehend this we can go forward.

Of course it will get longer. How do you think an LC based PFC works? It works by essentially extending the conduction angle .... i.e. the time the capacitor is being charged.

No it won't.  Voltage droop on capacitor after peak is related only to capacitance and load current.  Amount of this voltage drop (amplitude of ripple) defines width of charging pulse, since capacitor is charged only from the bottom point to next peak.  This bottom point was defined by discharge cycle thus charging has nothing to do with it.  PFC does not work by by extending conduction angle but rather eliminating (shifting) phase between voltage and current to present resistive load to mains.  Averaging (filtering) current pulses coming from PS to draw current from mains during whole cycle is exactly what Furman does.  They call it (improperly) Power Factor correction but it does not change any conduction angle.  It only averages current pulses over whole period.  When you comprehend this we can go forward.

Your understanding of electronics is poor, IMHO and I find you keep arguing just for the sake of it.  Sorry, for the "when you comprehend..."  but that's the unpleasant language you use and another reason I don't want to continue discussing this and perhaps anything else in the future.