MuzikMan said:
That was a very lucid, well thought out, articulate rebuttle.
Thanks, Man.
I'm home from work; sick with the flu. You're just seeing about three and a half hours of an audio-obscessed technician's fever-influenced thoughts.
I've been pretty frustrated with some of the dogmatically spoken advice I usually see here concerning choosing speaker and head ratings. It takes just a little more wisdom and knowledge, and a little more understanding of the user's requirements to make much more intellegent optimizations.
The most common 'potentially wrong' advice I see is this obiqitous, dogmatic general proverb that "your amp should be at least twice the rating of your speakers". This is does not hold-up all-alone as 'blanket-statement' like that. That statement is only a good rule-of-thumb if the requirements are that '
you want your speakers to be as small as possible, and you want to produce an authoritive, hi-fi clean-tone'.
That over-simplified proverb would be much-fixed if it were restated "your amp should be at least twice the rating of the loudest average power that you'll ever use it for - assuming you want a clean-but-authoritive, hi-fi sound". It could be pretty-well all tied together, yet still be reasonably true in a general sense, by adding "if you've already chosen an amp by the above criterion, and it's as small as as you dare have, and now you want to select the weakest speakers that you dare to go with too, then choose them to be half the rating of the amp".
The question is begged "should bassists really put their rigs together by these priorities, in this order??".
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If you simply break that proverb apart into a few of the important facts that it's derived from, and consider them seperately, we can be offering MUCH more accurate advice to the many questions that we're trusted with on this subject:
- The main trick to authoritive, modern, hi-fi, CLEAN-tone (IF that's what you want) is to be able to accuratly preserve short-duration dynamic transients all the way from the string to the audience, that exceed average waveform peaks by about double-the-power.
- Short-duration, non-clipped, low-distortion waveform excursion headroom is NOT included into amp power specs, but IS included into speaker specs. This confuses some. You may simply double your required average continuous power requirement to approximate the amp headroom that's desireable for this kind of sound-feel.
- If a bass signal waveform is clipped - whether it be by an effects pedal, or in a preamp or power stages of an amp... doesn't matter - then most any amp, if it's volume is pushed, will be able to truly output considerably MORE than it's rated power; theoretically, for a worst-case, hard-clipped square-wave as-compared to a pure, simple sine wave (both of these extremes unlikely for normal bass guitar playing), an amp with a perfect, 'stiff' power supply (won't be the case either, but a heavy-duty, over-built amp could get close) can make available to a speaker TWICE the power it would be capable of for the pure sine - that's abslolute worst-case.
- A clipped waveform is a valid, reasonable sound for making music with a bass. This axiom goes along with 'it's valid and reasonable for a bassist to never require a certain clean, dynamic, hi-fi 'headroom'-sound out of his amp'.. DANG-IT!!
- If a waveform is compressed - like with a compressor-limiter - then usually the average power over time is appreciably more than the same practical volume settings without the compressor - both in the amp and speakers.
- Certain not-super-uncommon kinds of compression - like fast-attack, higher-ratio, lower-threshold setups - tend to reduce the benifit or need for waveform excersion headroom, but this is partially offset by some more technical considerations; things like supply sag from input transformer regulation or resiviour capacitance, or heat-related issues. This makes the 'have twice as much amp power rating as you'll need at the loudest gigs' still hold as a reasonable rule.
- The only reasons to have your total cab power-handling capability 'just barely be enough' are reasons like if you're looking for minimum size and weight, or minimum cost, or that it's somehow what you're just 'stuck with it' or something - otherwise, there's nothing wrong with having more or bigger speakers than you need (there are a couple reasonable arguments for advantages gained from 'a larger cone area', in fact). An exception to this may be that I've read reports of some cabs inwhich their sound somehow blossoms or otherwise firms-up or gets better 'when you drive them hard', but I don't think most cabs are like this.
- Uhh
... ... ...
I think my fever's getting worse. ...Must rest now...
Joe
