Speakers
Question: can the Flextone be operated safely without speakers?Answer: yes, unlike a tube amp it can.
Here is what Line6 says about it (excerpt taken Nov 13, 2007):
Q: Can I run my Line 6 amplifier without a speaker load (i.e. not connected to a speaker)?A: All Line 6 amplifiers (with the exception of the Spider valve series) are safe to run without any speaker load connected. This is ideal for running headphones without a cabinet for fear of waking the neighborhood during those 2 a.m. moments of inspiration. ***The Spider Valve series must have a speaker load connected to avoid damage to the output transformer.***
Different speakers
The Flex3 comes with Celestion G12P80 speakers.Changing speakers has a big effect on how the Flex3 sounds. A number of Flex3 users have replaced the stock Celestion speakers with something else and like how it sounds.
Some cabs that are modeled have a frequency response that goes well beyond what the stock Celestion speakers are able to reproduce reliably. In other words, the Celestions act like a low-pass filter to the signal provided to them.
So anything you do to the speaker's high freq response you will hear well. You could hook up a pair of 8 Ohm PA cabs to a Flex3XL and use it like that. You could even use it as an acoustic amp that way. All you have to do is find a clean amp model you like and select no-cab as a cab model.
Line6' claim is that the FLextone III is a POD3 with a power amp attached to it. And so it is.
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