The output impedance of a power amplifier is always less than 0.1 ohms. There are no 8 ohm amplifiers on the market!
You can use your so called "4 to 8 Ohm's output" amplifier for your 10 ohms loudspeaker. All amplifiers have an output impedance of less than 0.5 ohms. You use impedance bridging when you connect the 10 ohm's loudspeaker. The "4 to 8 Ohm's output" means only that a 4 to 8 ohm loudspeaker will be adequate and not that the output impedance is 4 to 8 ohms! Scroll down to related links and look at "Impedance bridging - Wikipedia".
On any given day you can hear manufacturers, distributors, sales people or even customers talking about amplifiers with a "4 ohm output" or an "8 ohm output". You might even hear them refer to something called an "8 ohm amplifier" if they have a loudspeaker with this impedance (resistance) that they wish to connect. This is a rather unfortunate and also inaccurate use of technical language. There are no 8 ohms amplifiers on the market. The source impedance will be less than 0.5 ohms.
First, you must know: There is no 4 ohm amplifier. All audio amplifiers have an output impedance of smaller than 0.5 ohms. So you use impedance bridging. No problem to connect the 0.5 ohm output to your 4 ohm loudspeaker. Scroll down to related links and look at "Impedance bridging - Wikipedia".
Hook it up. You must know: There is no 2 ohm mono amplifier. All audio amplifiers have an output impedance of smaller than 0.5 ohms. So we use impedance bridging. Scroll down to related links and look at "Impedance bridging".
The most used instrument amplifiers are also some of the most popular amplifiers namely Marshall, Crate and Fox amplifiers. The impedance of these amplifiers does not need to match making it perfect for instrument use.
For smaller values (eg below 1000), simply use ohm, for biggers (above 1000000) use megohm, between them use kilo-ohm.
He uses a Randall amp.
We do not use transitors from 4 to 10 ohms. We use resistors.
The most used instrument amplifiers are also some of the most popular amplifiers namely Marshall, Crate and Fox amplifiers. The impedance of these amplifiers does not need to match making it perfect for instrument use.
yes
No. Not and maintain good balance and dynamic range.
Yes, if you use two 4 ohm speakers or or one 4 ohm resistor and a 4 ohm speaker to equal the 8 ohm resistance per channel. An important thing to note about this, is that you will need to make sure you get a resistor that can handle the current. You can go higher in resistance but not lower, it must be equal to or higher. Something important is added: The amplifier will have an output impedance of around 0.04 ohms. In hi-fi we have always impedance bridging. Zout