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    SKU: VMS-300-PAR

    OSD VMS 300In Wall 300W Slider Volume Control, Speaker Impedance Matching (White, Black, Brown) Decora Style

    Purchase OSD In Wall 300W Slider Volume Control, Speaker Impedance Matching White, Black, Brown Decora Style
    • Outdoor Speaker Depot SKU: VMS-300-PAR vmheduimmasl
    • $38.44

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    OSD Audio’s VMS300 is an impedance-matching volume control for adjusting the volume of a pair of speakers within a whole house audio system. Ideal for dining rooms, saunas, porches or other areas of the house where you want to add sound, the VMS300 maintains the full hi-fi audio frequency response with no low frequency roll-off and is equipped with the same features of volume controls that cost twice as much. Rated at 300 Watts peak, the volume control includes adjustable jumpers to add up to eight pairs of 8-ohm speakers simultaneously, and the impedance-matching feature helps stabilize the ohm load going back to the amp or receiver to avoid overheating. This is a complete volume control kit that fits into a standard single-gang box and includes the VC, junction box, screws and assorted color trim plates (white, ivory and almond) so you can choose the color that best matches the room. Compatible with almost any dedicated audio zone or whole house system, the electronics inside the VSM300 are designed with a ruler-flat frequency response while the 12-step slider provides noise-free volume control and a wide range of listening volumes.

    • Decora style impedance-matching volume control for whole house audio systems and dedicated audio zones
    • Rated at 300 Watts peak with minimal bass roll-off
    • Impedance-matching helps stabilize the ohm load to avoid overheating
    • Accepts up to 14-gauge wiring and fits in a standard gang box with a depth of 2.9”
    • Includes junction box, screws and white, ivory and almond trim plates to match any room décor
    • Precision electronic design provides low distortion and a ruler flat frequency response
    • 12-step linear slider for pop-free control and a wide range of listening volumes
    • Installs easily and works with almost any audio system

    What Is Impedance Matching Volume Control?
    Impedance is a measurement of resistance to alternating current. Speakers are specified by impedance, and a common value is 8 ohms. When you’re connecting multiple speakers to a receiver or amplifier, you need to stay above the amp’s minimum load requirements because going below the impedance rating can overheat or even damage expensive equipment. Volume controls such as the VMS300 have selectable impedance so you can match the impedance with the number of speakers being controlled with the capabilities of your amp. A basic multi-room system will typically have an amplifier/receiver, a speaker selector, four to eight pairs of speakers, and volume controls. Impedance-matching volume controls feature three settings depending on how many speakers you are connecting. For one to two pairs of 8-ohm speakers, the setting is 1/2x; for three or four pairs of 8 ohm speakers, the setting is 4X. Volume controls do not add gain (volume) to your speakers but simply attenuate the volume up or down. During setup, you'll set the source volume to its optimum level, then the volume control turns the sound down to inaudible levels.

    Warning: California's Proposition 65


    This product can expose you to chemicals, including vinyl chloride, which is known to the State of California to cause cancer. For more information, go to

    • Volume Control Type: 300W Impedance Matching Slider Style
    • Power Handling: 300W Peak; 150W RMS Per Channel
    • Frequency Response: 20Hz - 20kHz
    • Total Attenuation: 52 dB (Max)
    • Steps: 12 (Make Before Break)
    • Impedance Matching for 1/2, 4, 6, or 8 Pairs of Speakers
    • *Can be Used as Non-Impedance Matching if Leaving Default on Jumper Setting at 1X
    • Wiring Requirement: Up to 14 Gauge Wire
    • Removable Input and Output "Quick Connect" Phoenix Connectors
    • Fits in a Standard Single Gang Box - See LV1 for Mounting Bracket
    • Unit Dimensions: (L x H x D) 1.62" x 2.5" x 2.5"
    • What's Included: White, Ivory and Almond Plates, Inserts, Screws, and Slider
    • Additional Colors Available: Black or Brown
    • Warranty: 5 Years
    28 Questions asked
    Have a Questions?

    What's on your mind?

    Jeremy • 12/17/2019, 2:17:43 PM Does this volume control work to completely mute a set of speakers?
    Customer Service • 12/17/2019, 2:17:43 PM
    Hi Jeremy, If the volume on your receiver is very high, even at the lowest setting on the VMS300 volume control, you could possibly hear sound. You can find a balance by turning the volume at the receiver lower. That way the lowest setting on the volume control is inaudible. Our SVC205 volume control includes an on/off switch; however, it is a knob style. CL/MA 1685
    Joe • 12/17/2019, 2:17:43 PM Can this volume control be used in a screened porch where it won't be exposed to rain, etc. or do I need to use one of the enclosed box style controls. I'd like to use this since it can be mounted in the gang box where our ceiling fan switch/controls are located.
    Customer Service • 12/17/2019, 2:17:43 PM
    Joe, Good question! The main concern would be exposing this non-marine rated component to moisture or hot/cold temperatures. I wouldn't recommend it, but I'd say it's doable if you protect it with even something such as a weather proof cover, similar to the one we carry. Would the wall that it's being installed into be part of the house or outside? -BM 2084
    Nik • 12/17/2019, 2:17:43 PM I connected a pair of OSD Audio ACE840 to this volume controller. I then connected the outputs from the receiver (Denon AVR 1905) to the volume controller. When I turn on the receiver the setting on the volume controller needs to be set at the max setting to hear even a faint sound from the speakers. when I turn up the volume on the receiver the it then shuts down within several seconds. I'm pretty sure I have all of the setting correct. Can anyone please shed some light on what the issue may be?
    Customer Service • 12/17/2019, 2:17:43 PM
    Nik, I just answered your question on the ACE840 page, but it looks like I have the information I asked for here. It sounds like a defective volume control, but can you tell me what the impedance switch is set to on the volume control (1/2x, 4x or 8x)? -BM 2448
    Ken • 12/17/2019, 2:17:43 PM I'm planning to set up my home theatre system. I'm using a Denon AVR e300. I'll have main front Left/Right/Center and surrounds. This will be the main listening area. There will be two additional zones. One for the Kitchen L/R and the patio L/R primarily for music. I am going to run the main speakers front Left/Right, the kitchen L/R and the patio L/R through a speaker selection switch. I will put in-wall volume controls on the Kitchen zone and the Patio zone. My question is: Should I also put the main front L/R speakers on a volume control or should I just control that with my receiver.
    Customer Service • 12/17/2019, 2:17:43 PM
    Hi Ken, That is one of those questions that would be based on preference. Personally i wouldn't have your main LCR on the speaker selector either. Control your whole surround sound from your receiver and then have your other 2 zones on the speaker selector with volume controls. CS 2571
    Pete • 12/17/2019, 2:17:43 PM Trying to use 2 of these on a single stereo channel pair of outputs off an amp to power 2 indoor and 2 outdoor speakers for 2 zones (stereo in each zone). I think a switch would be redundant since u can just turn down either slider to essentially turn off a zone. The amp will only do as low as 8ohms per channel. Based on what ive read, it sounds like the amplifier side of these transformers is only 8ohms. The issue is that if the amp side of the volumes are 8ohms, with 2 volume controls on each channel output, the amp would see 4 ohms. Each speaker is 8 ohms. Soooo, can i use the impedance matching to change the amp side and get each slider to show 16 ohms per channel, so that when there is two transformers wired in parallel, each channel on the amp is actually seeing 8ohms? I'm essentially just wiring the exact diagram in the manual that they come with, but its not clear on if the impedance matching function also can be used to adjust the impedance to the amp. Soo- 4- 8ohm speakers. 2- 8 ohm amp channels (1 left, 1 right). 2 zones, each with 2 speakers, 1 left, 1 right. And 2 volume faders, one for each zone.
    Customer Service • 12/17/2019, 2:17:43 PM
    Hi Pete, Good question. If the amp/receiver can only handle 8ohms, we have to be very careful. The volume controls will not show it a set impedance, so that wouldn't be a solution. Do you know the exact model number for the speakers you are using? Can you let me know? Most 8ohm advertised speakers are actually 16ohm per speaker but they advertise it as 8ohm, because they are expecting you to run it with another pairing speaker, which drops the load to 8ohms. If that's the case, then you should be safe just setting the volume controls to 1/2x. BM 2643