Measurements and conclusion
Contents
We also measured the Yeti Reference 1000 watts, of course. We took “synthetic” measurements as well as a practical measurement on the Bryston Power Pac 300 power amplifier.
Measurements were made with the Prism dScope III, a GW Instek programmable AC generator, Rigol Function generator (60 MHz) and the Rigol spectrum analyzer.
We see that the Yeti can suppress noise with 55dB. Neat! When measuring with the Prism, we see that filtering starts around 2500 Hz, which again is a fine performance. We see a maximum of 42 dB, however, we are measuring within 100 KHz there. On the Rigol spectrum analyzer it is a bit more, but we are at 1 MHz there. All in all, very neat results.
What is more interesting is the effect in a real life situation. For that, we measure at the speaker output of the Bryston amplifier. This is connected to an 8 Ohm dummy. The Prism sends in a 1 kHz signal. The power delivered is 1 watt.
We can now see that the Yeti really does improve the noise floor. It’s not so much that the entire noise floor drops, but the whole thing becomes quieter. We see spikes disappear.
If we then do a measurement through the AC generator and add some noise and DC as well, we see that even then the Yeti continues to do its job well. Unfortunately, we cannot add DC when the Yeti is in between: the balanced transformer does not let DC through, causing the AC generator to go into protection mode.
All in all, these are neat results that we see. This filter just does its job: audibly and measurably.