• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Testing Amplifiers / Pad

On a completely different note from my other post, does anyone here have experience with testing using Distortion Analyzers or Harmonic Analyzers? Specifically, I have access to some really nice equipment, but I would need to build a pad to convert from my standard output impedances to the 600 ohms that most test equipment uses as the input impedance. It would also have to attenuate significantly, if I understand correctly.

This is part of a senior project for school, and I haven't found any resources on this topic yet. Any advice is greatly appreciated.

Hey Zap,
No distortion analyzer I've ever used required a 600 source for it's input. And I have used many different types including SoundTech 1700B, Amber 3501A & 5500, HP 334A, 8903A/B, Tek AA501, Boontons & my current favorite, the HP 339A shown below. But many sources do have a 600 ohm output impedance which has been the standard for many years to provide a level of compatibility between products.

Distortion analyzers have built in attenuators on the input for setting level. Some even have automatic level setting. You'd only need to attenuate if your source amplitude was past the range of the unit's maxium input. This is up to 300 volts RMS for the HP units.

Sooo....what analyzer have you acquired?



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