milan.pohancenik
Inspired
I own a TwoNotes Captor 8ohm. I've been using this load box for quite a while, but was never really satisfied with it. When I used it as a DI box between amp and cab, it was fine (the amp was seeing a real cab load). But when used as a load box, it sounded like the amp wasn't really getting a reactive load. So I made an experiment. Took the Matrix, plugged into the captor, made a cable with just 0.2 ohm 50W resistor and measured the impedance curve. I also measured the DC resistance of the captor and even the voltage of the Matrix at the output through the whole spectrum, so that I can then correctly calculate the impedance.
And now the reveal ==>
The DC resistance of an 8 ohm load box was 25.1 ohm!!!! (What????) -> I'm not sure if this is just a bad battery in my multimeter, but I'll verify.
And this is the actual impedance curve plot made with a 20Hz-20kHz sine wave sweep. This just confirmed, that the captor is not really a reactive load as it should be...
TwoNotes Captor 8ohm:
And this is the frequency plot of the Aiken Amps designed load box (well ... it really looks different than the Captor's)
AikenAmps designed load-box:
Bonus -> The Matrix frequency output plot
It may seem that it's not really flat, but it is veeery flat indeed. Notice just a difference of not even 1dBu between 20Hz and 20kHz!!
And now the reveal ==>
The DC resistance of an 8 ohm load box was 25.1 ohm!!!! (What????) -> I'm not sure if this is just a bad battery in my multimeter, but I'll verify.
And this is the actual impedance curve plot made with a 20Hz-20kHz sine wave sweep. This just confirmed, that the captor is not really a reactive load as it should be...
TwoNotes Captor 8ohm:
And this is the frequency plot of the Aiken Amps designed load box (well ... it really looks different than the Captor's)
AikenAmps designed load-box:
Bonus -> The Matrix frequency output plot
It may seem that it's not really flat, but it is veeery flat indeed. Notice just a difference of not even 1dBu between 20Hz and 20kHz!!
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