Why is low voltage bad for amps?

[Mikey Bates]

kinda like being dehydrated. but for amps its depowered. you can run as fast. but someone is pulling you with a rope making you. at some point your oing to collapse (:

[LZTYBRN]

Why does it pull more current? Like what physically goes on inside the amp to make that happen?

I believe it's because of the regulated power supply, which attempts to always keep power output the same.

[skittlesRgood]

ohm's law.

its not just a good idea.

its the law.

[Skullz]

Low voltage creates a spiraling death for regulated amps, as the voltage drops it requires more power to play the same volume and as the voltage continues to drop it draws even more power and gets to the point of no return and goes nuke and makes the magic smoke.

Unregulated power supplies will decrease the volume as the voltage drops so it will save your amp from going nuclear on low power and conversely if you add more power to the amp it will increase in power output.

[SnowDrifter]

That's an interesting point, Skullz.

So is this less of an issue with unregulated power supplies? Like for example by BC3500, would that be less effected by drop than an amplifier with a regulated power supply?

[neuspeedescort]

ever tried to spool a small turbo on a large motor. its kind of the same theory. to much effort for what is designed for.

NEUMAN

[STEvil]

You mean a large turbo with a small motor, but no that analogy doesnt work if you understand it really.

The components are meant to work at a certain voltage (12-18 as mentioned before) and if used at that voltage they will consume a known amount of current (amperage) to produce a known amount of output power. With current regulated amplifier technology this is controlled by cycling the mosfets on and off to create a steady amount of power for the second half of the amplfier. Less voltage means the controller of the mosfets cycles the "on" time longer which means the mosfets build up more heat. Heat creates resistance which means the fet controller must cycle the fets longer again which can create further voltage drop.. which means longer duty cycles...

This is known as a "thermal cascade" and as you can see it is not the voltage that is the actual death culprit but just a factor that drives the issue.

High voltage can kill an amplifier by creating what is known as electron migration. Basically arc (stick) welding inside the electrical components. Computer processors are an example of something that is very suceptible to this - hence why overclocking with increased voltage has the possibility to degrade or destroy processors. Pentium 4's were great examples of this

[8ight]

You mean a large turbo with a small motor, but no that analogy doesnt work if you understand it really.

The components are meant to work at a certain voltage (12-18 as mentioned before) and if used at that voltage they will consume a known amount of current (amperage) to produce a known amount of output power. With current regulated amplifier technology this is controlled by cycling the mosfets on and off to create a steady amount of power for the second half of the amplfier. Less voltage means the controller of the mosfets cycles the "on" time longer which means the mosfets build up more heat. Heat creates resistance which means the fet controller must cycle the fets longer again which can create further voltage drop.. which means longer duty cycles...

This is known as a "thermal cascade" and as you can see it is not the voltage that is the actual death culprit but just a factor that drives the issue.

High voltage can kill an amplifier by creating what is known as electron migration. Basically arc (stick) welding inside the electrical components. Computer processors are an example of something that is very suceptible to this - hence why overclocking with increased voltage has the possibility to degrade or destroy processors. Pentium 4's were great examples of this

Here is some good info. As for processors, extra voltage is OK since you have far more diverse and powerful cooling options than you do with an amp.

[SCS_Audio]

Why does it pull more current? Like what physically goes on inside the amp to make that happen?

I believe it's because of the regulated power supply, which attempts to always keep power output the same.

How many of today's amps have regulated power supplies as opposed to unregulated? This would mean for the most part they can output the same power on a range of input voltages (say 11-15 volts). They will obviously draw more current the lower the voltage goes to make the same output power (Ohms Law).

The most common amp that comes to my mind is the JL 1000.1 Slash series. These are regulated on both the input and output stages from 11-14.5 VDC and 1.5 to 4 ohm loads. Power output does vary slightly (a few hundred watts tops) but they are much more consistent than unregulated amps. Major drawbacks are efficiency and all that heat created when the voltage drops and current goes through the roof!

[STEvil]

You mean a large turbo with a small motor, but no that analogy doesnt work if you understand it really.

The components are meant to work at a certain voltage (12-18 as mentioned before) and if used at that voltage they will consume a known amount of current (amperage) to produce a known amount of output power. With current regulated amplifier technology this is controlled by cycling the mosfets on and off to create a steady amount of power for the second half of the amplfier. Less voltage means the controller of the mosfets cycles the "on" time longer which means the mosfets build up more heat. Heat creates resistance which means the fet controller must cycle the fets longer again which can create further voltage drop.. which means longer duty cycles...

This is known as a "thermal cascade" and as you can see it is not the voltage that is the actual death culprit but just a factor that drives the issue.

High voltage can kill an amplifier by creating what is known as electron migration. Basically arc (stick) welding inside the electrical components. Computer processors are an example of something that is very suceptible to this - hence why overclocking with increased voltage has the possibility to degrade or destroy processors. Pentium 4's were great examples of this

Here is some good info. As for processors, extra voltage is OK since you have far more diverse and powerful cooling options than you do with an amp.

Depends on the process used for the processor. Some are high leakage, some are low, and cooling doesnt change electromigration until you get near to the point of superconductivity of the silicon used to make the CPU.. if you can get there without hitting a "cold bug" point first.