Simulating Speaker Impedance Mismatch

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Guitar folklore has it that SRV and Joe Walsh intentionally mismatched their speaker impedance. I imagine others have done this. The general idea is you plug an 8-ohm speaker into the 4-ohm jack or vice-versa.

The Axe-Fx allows you to replicate this behavior using the Transformer Match control. To simulate plugging an 8-ohm speaker into the 4-ohm jack set Transformer Match to twice it's current setting (i.e. 2.0). For the other way around set it to half (i.e. 0.5).

And you don't have to worry about frying your OT.
 
And now I'm going to run downstairs and try this. Thanks for the tip Cliff! You the man!
 
Remember reading in a Mesa Boogie manual to try an oHm mismatch for a different tone.

Wouldn't dare try it with my Marshall though. :)
 
I ran an old Bassman head (4 ohm OT) with an 8 ohm speaker. Sounded really cool- the breakup came on a bit sooner. The Transformer Match control is my favorite tweak on the AFII.
 
Why not a sticky then?

there'd probably be too many on the front page of the forum. sticky's are usually for important information concerning the forum itself, or very important announcements from the company, not tips and tricks usually.

i think the Wiki or a similar site is the best place for this type of info. i was previously working on a site similar to a Wiki, but more from a troubleshooting standpoint, but also these tips and tricks.

strangely, i don't understand how to navigate a Wiki other than looking at "All Pages" or whatever it's called. it's just confusing to me and i can't find anything unless i type in google "amp block axe-fx ii wiki" hahaha! so we'll see if i can go back to developing my idea sometime soon :)
 
Yes, a separate sub-forum would be best as I post these but eventually they end up with the dust bunnies.

Why not a sticky then?

...a read-only forum perhaps, consisting exclusively of "Cliff's Notes" so these tidbits would always be easily found/seen/uncluttered and any discussion regarding the topic can be done in the regular forums?

I thought this item should be a sticky somewhere too as it contains so much useful information for how amps work and how it applies to the AFX:

http://forum.fractalaudio.com/axe-fx-ii-discussion/77539-ghost-fizz-7.html#post947075

Interesting info on mismatching the output transformer; having specific numbers for the ratios/impedance is cool.
 
Found this little knob a few days ago and noticed I preferred it around 0.6 - 0.7 something. And now I know what it actually does too ;)
 
- To search on the forum for Cliff's latest post, go to advanced Search, type FractalAudio in the User field, and search.

- All of Cliff's sticky-worthy quotes have been wiki'd over the past years. Type Cliff in the Search field in the wiki and search; the result will list all wiki pages containing Cliff quotes.

Or go to this page.

Or in Google:
"cliff site:wiki.fractalaudio.com/axefx2"
 
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Great great info! Thank you!!

Was always curious with this!!

Since my early years.....rule of thumb was always lower ohms into higher.

Was too afraid to go the other way around!....even for closer numbers!

Now,.....we can satisfy the curiosity! ...and not kill the cat (or amp) LOL!!
 
what are the general tonal implications of the mismatch - so I know what I'll listening / feeling for
 
I just did it real quick, but it seemed like 2 was squishier and more gain, breaking up easier. 0.5 was brighter and harsher. 2 was also quieter, and 0.5 was louder, so i had to adjust the level accordingly.
 
Guitar folklore has it that SRV and Joe Walsh intentionally mismatched their speaker impedance. I imagine others have done this. The general idea is you plug an 8-ohm speaker into the 4-ohm jack or vice-versa.

The Axe-Fx allows you to replicate this behavior using the Transformer Match control. To simulate plugging an 8-ohm speaker into the 4-ohm jack set Transformer Match to twice it's current setting (i.e. 2.0). For the other way around set it to half (i.e. 0.5).

And you don't have to worry about frying your OT.

PSA

For what it's worth... if you fry output transformer...

burnt2.jpg

It is time to stop the brutal and horrible mistreatment of OT in the quest for tone. How can we prevent such crimes against the defenseless OT in your tube amps? Well, the Axe-FX II = no friend output transformers. It's time to stop the brutal treatment of OT. Do the right thing. Buy an Axe-FX II when mismatching your speaker impedance.

;)
 
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