Audio Radio Ruisfilter Stereo | Car Stereo Audio Filter Isolatie Automotive versterker ruisonderdrukker

Sound is noticeably muffled but does removes pops an bangs now aftermarket stereo fitted. Afraid I just binned it

Il prodotto fa diminuire il volume della musica

The item was easy to install fitted to rear of stereo stopped all noises going through subwoofer great item thankyou

Typically these filters are pretty simple designs It's a box with some ferrite cords and a capacitor.This doesn't really work very well and drastically shifted the signal to noise ratio to being well noisier.

This compact unit consists of just two audio transformers operating in a passive mode - no power required. As with all transformer based circuits, there is some loss to be expected from input to output, and the lower audio frequencies will tend to drop off noticeably.Not mentioned in the listing is that this unit is ideal for interfacing equipment as it provides excellent isolation. There is no physical path from input to output.For Amateur Radio use I would thoroughly recommend this unit, it handles the narrow range of frequencies required very well and its performance for data transmission (FT8) is excellent. The only addition that may be required is the provision of isolation for CAT control. A suitable optocoupler would suffice.The poor frequency response is no doubt due to the small cores of the audio transformers.Surprisingly, the transformer resistances differ from input to output suggesting the windings ratio is not 1:1.220Ω/155Ω were measured although it will be the actual impedance that matters most. Perhaps the difference is an attempt to overcome natural losses in the transformer?Also noted, there is no strain relief on the wiring, so pulling on the wiring should be avoided.The writing on the box is in Chinese but translated is:Green side - "Audio Filter Wiring diagram" with (enter & output) in tiny graphicsWhite side - "Audio filter"Good product, decent price and well worth it. It will certainly filter out some external noise from the line, but if you're an audio connoisseur then you may well be disappointed with the device's frequency range.