Amperage 2 vs 4 channels amplifier

Although an amplifier max current rating doesn't represent anything useful, however, if two amplifier both rated 100watt/channel, one max current rated 50A and the other one rated 30A, we can assume that the 50A rated one has a beefier power supply.

Max current represents how beefy the output stages are but it does not  mean the power supply could handle more than 1 channel doing this at once. It's' just a measure if the amps ability to handle difficult loads. Bragging rights, if you will.

Also keep in mind for HT, the center channel has most of the output, surrounds have the least, especially if following the THX model of crossing them all over at 80 Hz. 

@imhififan
Not necessarily, especially if the amps being compared are from different manufacturers, because (using your example) the amount of time the 50 amperes and 30 amperes can be supplied for is not usually specified. For example, the 50 amperes may be suppliable into zero ohms for only 10 milliseconds, while the 30 amperes may be suppliable into zero ohms for 25 milliseconds.

Also, the amount of current that can be supplied into zero ohms for these brief amounts of time may be limited by the output impedance of the particular amp, which is unrelated to the power supply.

So generally speaking I don’t think these specs can be used as an indicator of power supply "beefiness," or of anything else for that matter.

Best regards,
-- Al

We have 2 amplifier from one manufacturers.

Amp 1 - 4 channels, 125 Watt, Maximum Current: 60 Amperes peak per channel.
Amp 2 - 2 channels, 125 Watt, Maximum Current: 100 Amperes peak per channel.
If we connect these amplifiers to identical speakers, first amp using bi-amping (all 4 channel in use)
and another (2 channels) just using bi-wiring cable.

Which amplifier will have more control on speakers?

Not necessarily, especially if the amps being compared are from different manufacturers, because (using your example) the amount of time the 50 amperes and 30 amperes can be supplied for is not usually specified. For example, the 50 amperes may be suppliable into zero ohms for only 10 milliseconds, while the 30 amperes may be suppliable into zero ohms for 25 milliseconds.

@almarg
That's true, thanks!