I played a Marshall JCM 800 Master Volume Lead amp for a long, long time. The preamp in that amp gave me as much distortion as I ever wanted. I played small clubs over the years and the master volume never got much past 2 and the preamp provided 'my sound'. I didn't quite get at all why one would want more crunch or drive by pushing a power amp section to its limit.
Fast forward a bunch of years and I get my Maz Jr. After playing it for about a year, I pick up an Air Brake. I push the master volume up to about 2 o'clock, and I'm blown away by the sound. I now get the concept of power amp section distortion. Preamp distortion is very smooth in terms of dynamics and it is consistent with its distortion. Power amp distortion gives you hair, gives you dynamics, allows you to dance between crunch and clean, and also provides a nice compression and sustain. It's almost like clean and crunchy at the same time. I recognized the sound from a few different classic licks from Brown Sugar to Springsteen's opening lick on Kitty's Back. Preamp distortion only provided cheap imitations of those licks.
Now I'm wondering, what the heck does 'Speaker Breakup' sound or feel like?
I was always careful to make sure that my speaker's power handling capability was more than enough to handle my amp.
I now realize that I was missing something without power amp breakup. What is this rock/blues player missing now without speaker breakup?
Last Edit: Oct 20, 2006 19:51:51 GMT -7 by GuitarZ
West Chester, PA Maz Jr Combo & Ghia Head American Deluxe Strat, '68 Gold Top P90 Les Paul, & Martin HD-28V named Bear
someone will be along for the technical explanation of that "speaker distortion" really is but in a mean time, for some infomative reads, i recommend that you go to: www.webervst.com/sptalk.html
and search for: motional impedance breakup speaker also does some filtering of the sound coming from the OT, kind of smoothing everything out once when you get to certain volume level.
as coreybox suggested, you can hear the speaker breakup yourself by using your amp and attenuator. dial in a good sound with no attenuation with your master all the way up (or near WOT) and start dialing in the attenuation a little bit and see how the sound change. i know that there's quite a bit of other stuff going on but this would be one way to find out how your speaker(s) play its roll in overall sound anyway.
or you can take a high-power 8 inch speaker (like 8A or 8F125 from Weber) of correct load and hook it up to your amp, then turn up the sound gradually and observe how sound changes as youturn up the volume level.
at any rate, as i understand, there are other things that "distort" as we turn up, like PI and OT to name just 2.
Last Edit: Oct 21, 2006 7:13:44 GMT -7 by mudskipper
You can hear the speaker break-up in one of my You Tube clips with the Hamer P-90s:
Even though it's "clean" you can hear just a little bit of hair on the notes. The amp is not cranked very loud, and the attenuator is only at -8dB. The Duncan P-90s aren't that hot, so I don't think it's the guitar pushing the amp to distort.
I could be wrong, but this is what I consider speaker break-up to be. With my 1x12 loaded with an EV, this breakup does not seem to exist. The EVM has a lot of headroom, while the Blues breakup fairly early. Or so I am led to believe.
I personally like the early breakup of the Blues, as it smoothes out what would otherwise be some pretty aggressive high end.
STANG RAY Head #82 w/ 2 Blues
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