The Difference A Speaker Can Make in YOUR Guitar Amp

The Difference A Speaker Can Make in YOUR Guitar Amp

Okay, lets say ya got a gig, and you want to be heard above the drums.  What will serve you best, a 100-watt Marshall or a 40-watt Fender?  Yea, that’s a "loaded" question.  There is no answer, because I have left out the most important piece of the equation.  I didn’t say anything about the Speakers!

Let’s start with this stat: a 100-watt Marshall is only about 3dB louder than the same model in a 50-watt version.  Twice as loud?  Not even close!  Truth is, once you get above about 40 watts or so, simply throwing more watts at a speaker cabinet is like urinating into a stiff oncoming breeze.  Call it the law of diminishing returns if you want, the logarithmic nature of SPL really starts to kick in the governor when your trying to get into the same volume realm as a snare drum being whacked silly by an energetic young musician.  It’s the physics of sound; you gotta play by THESE rules.

So if a doubling of wattage (from 50 to 100)only results in a slight increase of overall SPL, what the heck is a club guitar player to do?  Just give up and admit that we will NEVER be as loud as the snare drum?  I think NOT!  It’s all in the speakers.

This topic is fresh in my mind; let me tell ya why.  I just recently bought a used Bugera 2x12 cabinet on craigslist real cheap.  It’s a nice looking, well built cab with that cool mono/stereo 4/8/16 ohm switching, and physically, it’s a perfect match for my Bogner Alchemist head.  I plan to cut about the center third of the back out to make it a semi-open back.  Also, I knew the speakers were some seriously light-weight cheapos, and that the only way they could be rated at 70-watts RMS was to open up the voice-coil gap to a point that they would be VERY inefficient; I was right about that!  Not a problem, as I’ll be re-loading the cab with WGS anyway!

So, why did dude sell the cab cheap after only one gig?  Glad you asked!  This is where it gets good.  Along with the Bugera cab, dude bought an 88-watt rated Egnater Tweaker 88.  Then came the reunion gig with his old band mates from high school, the other guitarist still had his old 65-wat solid-state Peavey Bandit with a Scorpion speaker, and that old Peavey ate his lunch.  Why?  The SPEAKER, of course!  Say what you want about those old Scorpions, they were LOUD!  A scorpion is a speaker with an efficiency in the 100dB range, and the Bugera is at 87dB.  That’s a 14db difference.  That’s huge, that, in fact is more than TWICE as loud.  But wait, there’s more.

Dude also said that his tone was boomy, and disappeared anywhere other than straight in front of his cabinet.  Meanwhile, the old open-back Peavey was filling the room.  Ah, that’s what I love about open-back cabinets; you don’t have to be directly in front of the cab to enjoy it.  Sure closed-back cabs are the kings of chugga-chugga thump-thump, but they sure are directional as all heck above about 200Hz.  The result:  in a club setting, most folks only hear the thump-thump, or in other words, they don’t hear a darn thing you’re actually playing.  In yet other words: the dude with the 30 year old SS Peavey blows your new golly-gee-wiz big dollar tube amp off the stage.

Just for the fun of it, the first thing I did with the new 2x12 Bugera cab was to A/B it against my semi-open back Avatar loaded with a WGS Reaper and Vet 30.  In all honesty, the Bugera didn’t sound BAD, it just didn’t make much sound at all.  Using my handy little Radio Shack SPL meter that I’ve had since my own high school days I measured an average difference of 15dB between the two cabs. That bears repeating: 15db!  Holy Cow!  That means that a 15-watt 2-EL84 amp would get about the same SPL (volume) through the WGS loaded Avatar as dudes 88-watt Egnater through the stock Bugera 2x12.

Do speakers matter?  Think about it.

See ya all next week! 

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