OSD Audio 300W in Wall Volume Control Impedance Matching for Home Speakers, Rotary Knob White SVC300

I bought this in order to be able to control speakers within a pool cabana. With the outside speakers set at appropriate listening level, the speakers inside the cabana were way too loud! This does a great job of allowing me to dial down the volume inside without killing the volume for people around the pool.As other reviewers have indicated, a standard electrical box is not going to be your friend. I bought a standard width box but went with the 3" depth and it made all the difference for me. I punched out the circular, washer looking things (Sorry I don't know what they are called) on both the top and bottom and was able to run the input wires (from the amplifier) in through the bottom holes and the output wires (to the speakers) through the top holes. This left me enough room within the box.I had no issue with 14 gauge speaker wire but I found the secret is to keep the amount of speaker wire exposed to the absolute minimum. The wire slid in nicely and the screw tightened them up firmly.It does a great job but I only gave it 4 stars because of the finickiness of installation and the need for the larger box.

I researched many different volume control knobs offered on Amazon and decided to give this one a go! The installation was a breeze! You will need a box extender as these units are quite deep but they’re easy to find on Amazon! When it comes to the knob itself it is very well built, there’s no pausing in the audio when adjusting the level (as others have mentioned) and you won’t be disappointed! Note: The instructions could have been a little clearer when setting the impedance matching toggle... also, I didn’t see this mentioned anywhere but the higher you set the toggle example 1/2x -> 4x -> 8x you’ll notice a drop in the volume output from your speakers however that is to be expected! Overall, I was very happy with this control knob!Like the title says I ended up purchasing another one! The second one was a little temperamental at first but that was due to some wiring that needed to be replaced and due to a more powerful amplifier! I replaced some wires and reduced the volume on the amplifier and now all is awesome with this one too!

At first glance it all looks straight forward....but then the installation reality of the product ends up be anything but. The contacts for the speaker connection will not take 14 gauge stranded speaker wire and remain in place after installation in a 3 x 2 x 3 junction box. The installation diagram in the instructions shows it being installed in a 'J" box, but obviously by someone who has not installed one. The speaker connectors are located on the rear of an already deep unit forcing the wires to be bent and may disengage from the connectors and short. The only way the unit can be installed with heavier gauge wire, is to not use a device box. Use a low voltage data communication wiring bracket. This information should be noted in the installation instructions. Then finally, the volume slider feels cheap and looks it, and you cant see the graphics imprinted in the plastic. Overall poorly designed.

The unit itself is solid. The internal electrical is solid, but you do need a fairly massive gang-box to house it. The detachable wire connectors are very helpful, but could stand to be a little larger or spread out a bit better. The volume control is better than expected, although if there is any problems with grounding, there is a predilection for static/squelch. The extra face plates are a nice bonus. You will likely need a very fine tipped screwdriver, electrical tape, and fine tipped connectors/soldering skills to complete the job to a professional and foolproof level.Other than that.... they worked as well as to be expected. And, it's such a great thing to be able to control volume levels to different areas.

I read the comments on this item and my only concern at purchase was the possibility the white cover and facing was not truly "white".Not a problem. If it was at some point, the manufacturer has addressed it. The white facing is spot on.The unit had the wiring connections well marked and installation was easy.I bought this unit as a test and I'm now going to buy two more.