"High Current"

El: what you are basically saying is that it is possible for a low powered amp to be "high current" even though it isn't "high powered" and i agree. It is actually much simpler and less costly to do something like that than it is to make a high powered high current amp. Regardless of the rail voltages used, so long as the amp can supply enough current into the various impedances that it encounters, it will be able to sustain the same voltage levels. This is what makes the amp a TRUE "voltage source". Sean
>

All good answers so far, IMO. Do understand that solidstate amps, because of their VERY-low output impedance, are 'constant-voltage' devices, varying current delivery as load impedance changes. 'ANY' SS amp can double power as impedance halves, again and again...if one starts at a LOW-enough point. True-high-current amps can do that at least once while starting at rated ('maximum') power. The 20-year-old class-A-biased Lazarus hybrid poweramp is rated at 50Wpc into 8 Ohms, 100Wpc into 4, and 200Wpc into 2 Ohms. THAT is 'high current' indeed. IMO, any amp that won't double 8-Ohm rated power once (into 4 Ohms) is NOT 'high-current'.

BTW, it takes lots of expensive engineering to build a HC amp. The relative sizes of the power transformer(s), rectifier, wire, circuit-board traces, driver and output transistors, etc. all affect the amp's ability to deliver high current flows.

To answer your middle-paragraph question, an amp's power is limited generally by its ability to deliver VOLTAGE into the test impedance. Eventually, ANY amp will clip its output waveform at some voltage, and its rated power will be calculated at some point below that clipping voltage.

On your paragraph-3 questions, I have no idea about the 1st half, but my example of the Lazarus answers the 2nd part.
.

Jeffreybehr: As discussed in another relatively recent thread, power ratings can be manipulated by the manufacturer. Even if they are rated to "double down", most amps DO NOT really do this, the ratings are just "fudged" to look good to the consumer. That is why i specifically stated "power at clipping" as it is a much more thorough, grueling and revealing test. With this type of testing, the amp either does or doesn't "double down". There is NO guessing involved, regardless of factory ratings at various impedances. Unfortunately, very few reviews actually perform or publish this type of testing, so getting good information becomes harder when trying to make an informed decision. Sean
>

Sean,

I'm surprised by your comment:

Unfortunately, very few reviews actually perform or publish this type of testing

for this is certainly something that Atkinson at Stereophile does regularly test and publish.

Regards,

Metralla: The audio world does not revolve around Stereophile alone in terms of equipment reviews. How many other reviews / reviewers do this? That was the point that i was trying to make. Having said that, i'm glad that Stereophile does perform such tests and it is one of the reasons that i still subscribe. Sean
>