Amp protection mode or home circuit problem?

I have an older amp and I live in an old house. Some of the electrical system in the house is original.

The amp is a Proceed Madrigal HPA2, essentially a Mark Levinson, 250 amps into 8 ohm, approx 500 into my 4 ohm Aerial Acoustics 7B towers.

From time to time the amp will 'stop' briefly in response to turning on a light or other appliance in the room on the same circuit. It starts playing again almost immediately. I don't know if this is protection mode or simply the power dropping below a certain level. But, it is certainly aggravating.

I'll preface this question by saying I know very little about electricity. What I'm wondering is, would running a dedicated line back to the breaker box (which is modern and has a few open breakers available) help with this problem? If so, what amp breaker?

I will also say that this is not intended as a sound quality upgrade of some sort. I just want the amp to stop cutting out. Thanks,

George

Does this happen at all times of the year? 
 

I had a similar issue with a digital component every time I used a light switch, but only during the winter when the humidity level was very low. 

Does sound like a circuit interaction. Doubt a light bulb is the culprit.

#1 You may have a bad outlet on the breaker, ie a used outlet has become a resistor due to aging/damage. Have all outlets on the breaker checked to make

sure none show signs of heating up and that all are in good shape where the house wiring attaches to the electric outlet. This can lead to fire, thankfully

I just had scorch marks when it happened to me. The flickering when another device was turned on was my first warning there was a problem.

#2 identify whats on the same circuit. Do not share the circuit with other high current devices, such as dehumidifiers, heaters, anything that significantly drives up

the amperage through the breaker. Know what the peak amperage is for the necessary in use devices and be sure that its not approaching the limit of your circuit breaker

Do check your manual for the AC input power consumption, thats different from the DC stereo output power. Typically it will specify AC wattage, you have to divide

this by mains voltage to get the breaker current demand. An amp usually operates much like a water tower, constantly pumping AC energy into a reservoir for later discharge

into a smaller stereo DC output circuit.

Separate circuit is a good idea if you have electrically noisy devices on same breaker but one can often groom these off to a different breaker circuit. Older houses often

have a full mains panel so that adding a new circuit means changing out the mains panel for a larger one, quite expensive.

I doubt the amp is the problem, power amplifiers have a robust power supply. Most AB amps keep playing for several seconds after losing power. Protection circuits operate on the amplifier output, not the input.

It's more likely that something upstream is dropping out, leaving the amp with no signal. Try plugging the upstream gear into a decent power conditioner. This one is good value, but there are lots of choices:

https://www.amazon.com/Furman-Aluminum-8-Outlet-Protection-Conditioning/dp/B000YYVLAK/ref=sr_1_1?crid=37WZTINYLFM6H&keywords=furman+pst-8&qid=1702825805&sprefix=furman+pst%2Caps%2C129&sr=8-1

Don't plug your power amp into a conditioner. It doesn't need conditioning, and the sound will be compromised. If you want to protect the amp from power surges, you could plug an iFi AC iPurifier into the same receptacle as the power amp. The iPurifier connects in parallel, not in series, and will not compromise transient amp performance the way a power conditioner will. 

To answer the dedicated power connection I would also install a hospital-grade outlet when running a dedicated circuit. I would suggest a 20-amp breaker and upsizing the wire one gauge.

But that does not fix the underlying problem of what is causing the amp to "cut out."   In reading this review:

https://skyfiaudio.com/products/proceed-hpa2-amplifier-from-mark-levinson-perfect-for-home-theater-or-stereo-250w-x-2

 The amp has some protection features that might indicate speaker cable issues, such as a short.  

If you are uncomfortable with AC power, please get professional help.  I would add to the above suggestions that loose connections on an outlet or in the panel could exist.

rjf

1 hour ago, bobfa said:

To answer the dedicated power connection I would also install a hospital-grade outlet when running a dedicated circuit. I would suggest a 20-amp breaker and upsizing the wire one gauge.

 

But that does not fix the underlying problem of what is causing the amp to "cut out."   In reading this review:

 

https://skyfiaudio.com/products/proceed-hpa2-amplifier-from-mark-levinson-perfect-for-home-theater-or-stereo-250w-x-2

 

 The amp has some protection features that might indicate speaker cable issues, such as a short.  

 

If you are uncomfortable with AC power, please get professional help.  I would add to the above suggestions that loose connections on an outlet or in the panel could exist.

 

rjf

Ever taken a hospital grade socket apart? Not much difference than a regular one except says Hospital and costs more. If you got the coin go for it.

Just now, botrytis said:

 

Ever taken a hospital grade socket apart? Not much difference than a regular one except says Hospital and costs more. If you got the coin go for it.

They are about $15, and the materials in the contacts are much more robust. 

Not the ones I have dealt with. Hence why it all is your frame of reference

42 minutes ago, bobfa said:

They are about $15, and the materials in the contacts are much more robust. 

 

I’ve tried these and been very impressed with the build quality versus my standard house outlets. For like $10. 
 

https://www.homedepot.com/p/Leviton-20-Amp-Industrial-Grade-Heavy-Duty-Isolated-Ground-Duplex-Outlet-Orange-R71-05362-IGS/100356987

8 hours ago, The Computer Audiophile said:

I’ve tried these and been very impressed with the build quality versus my standard house outlets. For like $10. 
 

https://www.homedepot.com/p/Leviton-20-Amp-Industrial-Grade-Heavy-Duty-Isolated-Ground-Duplex-Outlet-Orange-R71-05362-IGS/100356987

So everyone wants to ignore the OP's clue "I live in an old house. Some of the electrical system in the house is original. " ?

hope the OP has good fire insurance if that plug circuit wiring is older than the 90's and hasn't been inspected for safety

1 minute ago, davide256 said:

So everyone wants to ignore the OP's clue "I live in an old house. Some of the electrical system in the house is original. " ?

 

hope the OP has good fire insurance if that plug circuit wiring is older than the 90's and hasn't been inspected for safety

I don’t think anyone wants to ignore anything. If you can help, please do so. 

Thanks guys. There is a Shunyata Venom Defender power conditioner in an outlet on the same line as the amp. The amp is plugged into a Furman Power Station power bar/ conditioner. So that side of things is covered.

I also noticed that today the amp blinked off for a second when a light in the room was turned _off_.

I have noticed no warm or hot outlets.

I have not followed this entire circuit from the room to the panel box but I can do that. I am pretty sure that there is some original wiring and outlets, which are 95 years old, in the circuit.

I've done home wiring before, but it was in a log cabin that we built so it was all new install and I was pretty much just doing what someone who knew what they were doing was telling me to do. So even though running a dedicated line would be fairly simple I will probably have an electrician do it.

If and when I do so I will make everything more robust as others have mentioned above.

Thanks again.

3 hours ago, GTB said:

The house was built in 1929. The existing wiring has been inspected. A lot of it has been replaced but not all by any stretch. 12 years ago when we did the renovation the inspector commented that there had been no problems with the wiring for 80 years and likely never would be. Most of the houses on my street are older than mine and most have older wiring than mine. No fires in the last 60+ years that I am aware of.

 

On the other hand, the wiring in the 1970s home I grew up in was aluminum and we had multiple scorched outlets before it was all replaced.

then the next key question is what is the amperage running on the circuit and if anything else is on it that has significant amperage, can it be moved

to a different circuit. What you are describing sounds suspiciously like a voltage sag when something is added to load.

@GTB, few things going on here.

I have a Furman box, used to protect UPS and 120V IT equipment. It has an overvoltage protection, that in severe cases latches on, and requires a manual reset. It's possible that an overvoltage occurs, but not enough for the latch to hold, but the outputs are disconnected for a time until the transient passes. Possible the Furman is too protective and is a defect unit.

A light switch can create an overvoltage (technically a transient), as the switch contact arcs as things age.

For now, plug the amp into a standard outlet bypassing the Furman and see if the drama changes.

Amps draw quite  a lot of current in pulses, rather than continuous draw. This creates stress on joints at receptacles, each one contributing to a drop in voltage. Many of these (10+) can cause problems for amplifiers. With a dedicated line, this problem is eliminated since there's no joining of wires any more, that's why (one of a few reasons) why a dedicated line is an audible improvement.

1929 wiring doesn't have the insulation properties of modern cables. If left alone, they could work, but putting an amp on them can physically rattle the insulation (due to pulses in current) over time and it starts to fall away.

Work out where the cables go from the amp back to the panel, maybe too many connections and not being tight is asking for trouble.

If you can still locate a lamp with an old fashion incandescent light bulb.

Plug it into the same AC outlet as the amp. Those old bulbs are very sensitive to small voltage changes.