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Question about high current amps versus "not high current amps"

Recently I read a reply to a post about a certain speaker, and the person who replied typed that (and I am going to paraphrase somewhat) the speaker required a high current amp to perform well and it wasn’t the WPC that was important.

Sorry as I am afraid that these are probably going to be  "audio electrical questions for dummies," but here goes:

I vaguely remember being taught the PIE formula, so I looked it up online for a quick review and if I am understanding it correctly,

P (power/watts) = I (current/amps) x E (electromotive force/voltage) .

My first question would be: if I am understanding that correctly, how can wpc NOT matter since watts are the sum of current x voltage? I mean if you have so many WPC, don’t you then HAVE to have so much current?

My next question would be, if I am understanding PIE correctly, is E/voltage going to be a fixed 110 vac out of the wall, or is that number (E) determined by the transformer (so it would vary by manufacturer) and it is that (different transformers that are used in different amps) going to be the difference between a high and a lower current amp?

Or am I completely off base thinking that P is wpc and P is actually the spec in my owners manual that lists "power consumption as 420 watts operate 10 watts stand by"?

And lastly, what would be an example of a high current amp and what would be an example of a low current amp?

Thanks.

 

immatthewj
westcoastaudiophile
466 posts
 
@panzrwagn +1 simplest test of amp current handling adequacy is to tap low frequency. driver membrane and checking voltage waveform at speaker terminals with the scope.. if voltage amplitude p-p observed is more than 10mV, then need to check speaker connectors, cable, amp relay contacts, and then try higher current amp design to see if it helps!
westcoastaudiophile
466 posts
 
@panzrwagn +1 simplest test of amp current handling adequacy is to tap low frequency. driver membrane and checking voltage waveform at speaker terminals with the scope.. if voltage amplitude p-p observed is more than 10mV, then need to check speaker connectors, cable, amp relay contacts, and then try higher current amp design to see if it helps!
moonwatcher
495 posts
 

I just wish that speaker manufacturers who make speakers requiring high current amps with amazing damping factors to simply recommend a few amps. It doesn't have to be an endorsement exactly but give a few examples and say, "high current amplifiers similar to these in specifications, quality, and capability."  That would go a long way to keeping customers happy. I'm looking at you Magnepan, but of course there are others out there too. Not all consumers are as clued into what the needs are, then they buy speakers and are not happy with them and don't understand why and maybe end up giving those speakers bad reviews on forums and such. 

helomech
1,782 posts
 


A Coda 16 has 280,000 uF of capacitance and can deliver 100 amps of current, per channel.

That’s what Coda claims about their No.8 amp as well (100A/Ch), however, my Yamaha A-S2100 integrated sounds more powerful and has considerably better bass authority than the No.8 I owned. Not sure why they feel inclined to make such an outrageous claim. They make good amps, that should be good enough.

 

dishman442's avatar
dishman442
49 posts
 

I will very quietly suggest that the best tool for evaluating how well an amp drives a speaker is to listen to the combination.  You can try to think your way into decisions but using those comparison tools on your head is much more fun and they will produce the best long term results. Shields up: prepared for incoming fire. 

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