XieguGNR1 Digital Audio Noise Filter, Noise Reduction, 22DB, Knob Control

This is an excellent noise suppression filter. The adjustable upper and lower band shaping filters/controls not so much. I have several of these and use them just for the noise suppression. I have had the BHI units in the pass and they don't come anywhere near as good as this unit. Best use is on SSB very satisfied and can recommend.

Bought this to complement my old ICOM R-70 Receiver,but made little difference,the ICOM can still hold it's own with its filters coupled with a ICOM SP8 speaker with filters, sent it back.

Xiegu GNR1 Digital Audio Noise FilterThis is a nice compact audio interface. It is roughly the same size as a mobile transceiver but not as deep. It is pretty hefty in weight, it won't slide on the table when you turn the knobs. It is quality and metal unlike some of the plastic hand held devices I considered. It really kills white noise static on the HF bands and has allowed me to turn off the high cut filter and noise blanker almost all the time. It is pretty much set and forget, I advance the "NR" knob to the first hash and have little reason to increase it. Listening to the ham bands is FAR more comfortable, there is no need to crank the volume to pull out weak stations and it seems to slightly reduce stronger station audio levels like an audio compressor. I haven't had to adjust the high and low filters but I haven't found a need to challenge it with super faint signals.Advancing the NR knob does reduce the audio output and you will have to increase output volume. If you run high levels of noise reduction and higher output audio the transition from transmit to receive will cause a 1 second noise crash as the unit "re-learns" the background noise. I suspect this will be a drawback for some people but if you don't crank the NR and output too high then it is tolerable and beats the heck out of the fatiguing white noise static that non DNR/DSP transceivers produce. If you are an impulsive button pushing knob twister you might not like this device but if you set it and forget it you will wonder how you lived without it.