Current Questions


More and more, I see the word “current” in audio reviews. The reviewers warn me that I’ll “need lots of current” for a given speaker but they don’t explain exactly what it is I need or how many “lots” is. I’ve looked at a few “Electronics For Dummies”-type sites but I’m still confused. A few questions:

 

—What is current?

 

—When someone writes, “These speakers need a lot of current,” what do they mean? Is sensitivity involved? Impedance?

 

—On the amplifier end, what specification measures current?

 

—Are there subjective considerations at work in that spec? The number of watts doesn’t tell me everything about loud an amplifier sounds. Does the number of [whatever measures current] similarly leave things unexplained?

 

—Everyone asks, “How many watts?” No one asks, “How much current?” Is it really so important?

paul6001

Showing 3 responses by 4krowme

Back in the late 70’s I read a review on a power amp made by (I forget) stating that the amp was capable of 35 amps of power per channel. This sort of talk lasted for a bit longer and constant current, power envelope, and other sorts of talk too.

It is pointed out in a previous post to sell the high points of a product within the confines of its capabilities. So, if there is a scratch on the hood, make sure and open it quickly and talk about the engine.

Before I continue, let me say that holmz gets it, i.e. in reference to my post. No BS, no put down or what is too commonly seen on this site, so thanks for that. Better that we can explain our writings to each such as is being done here. 

 

 Now I do agree with the idea that this involves more than a single component. The basic question however, now addressed, was about current and it's definition for the common man. We tend to automatically answer in a way we know, but not everyone knows the meaning behind V=IR, or E=mc2 for that matter. So from the beginning there little chance by this definition that the OP will 'get' the meaning.

 Man, I do remember all the talk back in the day about current/amperage output of power amps, X WPC, TIM and anything 'new' to sell.  In some cases it was relevant for the consumer, but then not so much in other cases.

 Once the idea of current is basically understood, then it is time to move to the next logical step of current need. Sorry, couldn't resist.

falconquest,

 After skimming through these many posts about a simple question, your answer has the best potential to answer the basic question asked by someone admits right up front that this isn't exactly his line of expertise. Thanks for that. The fact that some of the posts accurately describe current with the inclusion of OHMS law, or other related truth, does not help the person who is asking in the first place. 

 When working with customers, one goal is to connect with them on the level that they are at and not just spew out your vast knowledge, using terms, definitions, laws, ad infinitum about the product or subject. What seems easy to understand with a background for reference in physics or electronics, is not where most people are at.

 In my case, don't even start with the basics of a tax form. Screw it, I give you the papers and pay you money for that. Explanation will often lead to even more confusion.