Help. Past amp had a current of 45 amperes. New is 66 amperes. what does this spec mean?

[Reminiscent Audio Guy]

Hello,
To the point.

Past amp had a on hand current rating of 45 amperes. New one was 66 amperes on tap. Noticed the difference imidealty and it was a positive one. I was wowed by the higher current of the amp and how it powered those passive speakers.

So. If company A states 66.0 Amperes of instantaneous current capability and Company B states 45 amps peak per channel.... Does this mean the 45 peak amps are 90 amperes total? or does the amp I have which states 66.0 Amperes mean per channel or to both channels which turns out to be 33 amperes per channel?


Asking because I am trying to determine if a power amplifier that is for sale - the Parasound halo A23+ @ 45 amps peak per channel is more than my Marantz model 50 which states 66.0 amperes but not if its total or per channel. Thinking of buying panels but do not want to waste money on a amp with more rms watts but less current.

Hope this helps. And thank you again for your help. Even sarcastic comments have helped with my learning so say what you want...I have learned so much from my first post to this one.
Cheers and yes I endorse beer.. I love beer.. especially Guinness with some whole buffalo milk mixed in.

 

[terryforsythe]

45 amps peak per channel.... Does this mean the 45 peak amps are 90 amperes total?

It depends on how the company performed the test to determine that specification. If they have a single power supply and only tested one channel at a time, maybe not. If it is a dual power supply setup (dual mono) or they tested both channels simultaneously, then the answer should be yes.

Marantz model 50 which states 66.0 amperes but not if its total or per channel.

It depends on how they specify their amplifier. If it does not state "per channel", my GUESS is that it is total. But, I don't know if that is the case. I would try to find more thorough specifications for the amplifier. If you cannot find any, then reach out to Marantz and ask. Hopefully they respond to your question.

 

[NTK]

It doesn't mean squat. If your speaker has a minimum impedance of 2 ohms. It will take the amp to output 132 V to drive 66 A though your speaker (assuming that meaningless rating is peak, that means 93 Vrms).

That's also equivalent to an apparent power of (66/sqrt(2))^2 * 2 = 4356 VA [ apparent power = rms_current^2 * impedance ], or 4356 W if the load is resistive.

How low is the minimum impedance of your speaker? Or better ask, into what impedance was the 66 A spec'd?

PMPO all over again?

 

[Reminiscent Audio Guy]

It depends on how the company performed the test to determine that specification. If they have a single power supply and only tested one channel at a time, maybe not. If it is a dual power supply setup (dual mono) or they tested both channels simultaneously, then the answer should be yes.


It depends on how they specify their amplifier. If it does not state "per channel", my GUESS is that it is total. But, I don't know if that is the case. I would try to find more thorough specifications for the amplifier. If you cannot find any, then reach out to Marantz and ask. Hopefully they respond to your question.

Thank you that was helpful, I just reached out to them but they have to confirm. The fellow on the phone stated per channel but will confirm with the engineer. The other answer posted by NTK is relevant but I have to get back to them about what impudence the 66A was spec'd at. Thank you.

 

[DonH56]

Whatever the difference you may hear it almost certainly is not (due to) the output current (number of amperes) it will deliver. The maximum current can be a function of other things more audible, like output impedance (damping factor) and power output, but the current (amperes) either amplifier will deliver is likely far more than you need and more than enough to destroy your speakers.

As others have said, peak and instantaneous are both ambiguous marketing terms, so how they are defined and tested by each manufacturer matters as much as if they are per channel, for both channels, or tested with just one channel driven (all possibilities). For a sine wave, the peak value is clearly defined, but marketing can use "peak" any number of other ways such as the maximum short-term power (often without defining how short a term). Likewise, how long is "instantaneous" in their test? There is a defined (originally by the IHF as I recall) burst test using 20 ms duration signal bursts but it is rarely specified in consumer product marketing sheets.

 

[DVDdoug]

That's also equivalent to an apparent power of (66/sqrt(2))^2 * 2 = 4356 VA

And you can only get 1800W out of a regular American 120V, 15A wall socket and then the circuit breaker blows. And since the amplifier isn't 100% efficient, and you might have something like a TV or CD player on the same circuit, you can't get that much continuous power into the speakers. (You could potentially-theoretically deliver more than that on the peaks because the power supply's capacitors store energy).

As long as the amplifier can deliver the rated wattage into the speaker impedance that's all that matters. We can calculate the current but unless you are the amplifier designer it doesn't matter.

 

[DonH56]

Just to be contrary (OK, "anal"), you can get short peaks much higher than 1800 W (or VA) from the wall as circuit breakers take a while to heat up and open. Still irrelevant for the vast majority of us, for whom even "just" 1800 W or even 100 W into our speakers is likely louder than we can stand (at least in the midrange).

 

[sergeauckland]

Just to be contrary (OK, "anal"), you can get short peaks much higher than 1800 W (or VA) from the wall as circuit breakers take a while to heat up and open. Still irrelevant for the vast majority of us, for whom even "just" 1800 W or even 100 W into our speakers is likely louder than we can stand (at least in the midrange).

Bearing in mind too that the 45, 66 amps or whatever don't come directly from the mains, but from the reservoir capacitors, so as long as the current draw doesn't go on too long, the mains breaker won't trip. I completely agree that these high currents are just spec points with little relevance to actual use.

S

 

[DonH56]

Bearing in mind too that the 45, 66 amps or whatever don't come directly from the mains, but from the reservoir capacitors, so as long as the current draw doesn't go on too long, the mains breaker won't trip. I completely agree that these high currents are just spec points with little relevance to actual use.

S

Yah, I started to go there as @DVDdoug also raised that point, but figured a discussion of power supply bandwidth, ripple, and all that jazz was heading too deep down the rabbit hole.

I still remember decades ago fixing a blown Sound Design all-in-one system rated 1000 W "peak instantaneous music power" from an output stage comprised of a 2N3904/2N3906 transistor pair...

 

[Reminiscent Audio Guy]

It doesn't mean squat. If your speaker has a minimum impedance of 2 ohms. It will take the amp to output 132 V to drive 66 A though your speaker (assuming that meaningless rating is peak, that means 93 Vrms).

That's also equivalent to an apparent power of (66/sqrt(2))^2 * 2 = 4356 VA [ apparent power = rms_current^2 * impedance ], or 4356 W if the load is resistive.

How low is the minimum impedance of your speaker? Or better ask, into what impedance was the 66 A spec'd?

PMPO all over again?

Thank you, I have to ask them that when they respond back.

Thank you that was helpful, I just reached out to them but they have to confirm. The fellow on the phone stated per channel but will confirm with the engineer. The other answer posted by NTK is relevant but I have to get back to them about what impudence the 66A was spec'd at. Thank you.

Here is the answer to the amp that puts out 45 peak amps into two channels...if you understand this better please explain.

"The 45-amp peak current rating per channel is measured with one channel driven at a time. This does not mean that the amplifier has a total of 90 amps available to be split across both channels. Instead, it reflects the capability of the power supply and output stage to deliver high-current transients under demanding conditions.

While the power supply is shared, it is robustly designed to support both channels with high dynamic headroom. In real-world use, unless you are driving extremely low-impedance loads at very high volumes, both channels will have access to substantial current for demanding speaker loads."

 

[Reminiscent Audio Guy]

It depends on how the company performed the test to determine that specification. If they have a single power supply and only tested one channel at a time, maybe not. If it is a dual power supply setup (dual mono) or they tested both channels simultaneously, then the answer should be yes.


It depends on how they specify their amplifier. If it does not state "per channel", my GUESS is that it is total. But, I don't know if that is the case. I would try to find more thorough specifications for the amplifier. If you cannot find any, then reach out to Marantz and ask. Hopefully they respond to your question.

Here is the answer to the first amp with 45 peak amps.

"The 45-amp peak current rating per channel is measured with one channel driven at a time. This does not mean that the amplifier has a total of 90 amps available to be split across both channels. Instead, it reflects the capability of the power supply and output stage to deliver high-current transients under demanding conditions.

While the power supply is shared, it is robustly designed to support both channels with high dynamic headroom. In real-world use, unless you are driving extremely low-impedance loads at very high volumes, both channels will have access to substantial current for demanding speaker loads."

 

[Reminiscent Audio Guy]

It depends on how the company performed the test to determine that specification. If they have a single power supply and only tested one channel at a time, maybe not. If it is a dual power supply setup (dual mono) or they tested both channels simultaneously, then the answer should be yes.


It depends on how they specify their amplifier. If it does not state "per channel", my GUESS is that it is total. But, I don't know if that is the case. I would try to find more thorough specifications for the amplifier. If you cannot find any, then reach out to Marantz and ask. Hopefully they respond to your question.

Hello, so thank you and much appreciated that you stated what you stated because I emailed both companies and asked them the exact question you phrased. I would have had no idea what to ask specifically which was how they tested their peak amps. Both companies stated what you thought, Single power source and one channel at a time. I got my answer so thank you for helping ask the appropriate question.

 

[Reminiscent Audio Guy]

Thank you to all who helped. I did get my answer. Clearly there is a lot to learn so if anyone knows of a specific book I can order about amplifier tech that would be appreciated. Thank you.

 

[Gyosa1]

FWIW , I have a Parasound A21 driving a pair of Ascend ELX Ribbon Towers … sounds great ….. I have also driven the Ascends with a PS Audio S300 amp - class D - sounds great as well …. Point being, any well designed amp will probably sound great .

The A21 and S300 couldn’t be any different from each other - polar opposites, design wise and price wise.. traditional class AB vs. class D … both sound great ..

Bk

 

[EJ3]

And you can only get 1800W out of a regular American 120V, 15A wall socket and then the circuit breaker blows. And since the amplifier isn't 100% efficient, and you might have something like a TV or CD player on the same circuit, you can't get that much continuous power into the speakers. (You could potentially-theoretically deliver more than that on the peaks because the power supply's capacitors store energy).

As long as the amplifier can deliver the rated wattage into the speaker impedance that's all that matters. We can calculate the current but unless you are the amplifier designer it doesn't matter.

Every wall socket (except for the GFCI ones [which are 15 AMP]) in my house (which was built in 1968) in Charleston, SC, USA are 20 AMP outlets (as are the breakers).
And when I had the new breaker box and new wiring done, I went with the same.

The maximum power that can be safely supplied by a standard electrical outlet in the United States is typically 15 amps, or about 1,800 watts.
However, it's important to note that this can vary depending on the type of outlet and the electrical code used in the building.

If we assume that circuit breaker limitations are not a consideration, it's still important to understand the capacity of an American wall socket. Here's some information to help you understand how many watts an American wall socket can handle:

1. Circuit Capacity: The capacity of a circuit determines how much power it can handle. In the United States, most circuits are designed to handle 15 or 20 amps. A 15-amp circuit can handle a maximum load of about 1,800 watts, while a 20-amp circuit can handle a maximum load of about 2,400 watts.
2. IMPORTANT!:-----Outlet Capacity: The capacity of an individual outlet is typically the same as the circuit it is connected to. ----So, a standard American wall socket can handle a maximum load of about 1,800 watts on a 15-amp circuit or -----2,400 watts on a 20-amp circuit.
3. MORE IMPORTANT!!!:-----Safety Considerations: It's important to note that even if an outlet can handle a certain wattage, it's always recommended to avoid overloading the circuit. -----Overloading an outlet can lead to overheating, damaged wiring, and increased risk of fire. -----It's best to distribute the load among multiple outlets or consider using dedicated circuits for high-power appliances.