SKU: VMS-100-PAR
OSD VMS100In Wall 100W Slider Volume Control, Speaker Impedance Matching (White, Black, Brown) Decora Style
OSD Audio’s VMS100 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 VMS100 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 100 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 VSM100 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.
Features:
- Decora style impedance-matching volume control for whole house audio systems and dedicated audio zones
- Rated at 100 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 VMS100 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
Warning:
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 www.P65Warnings.ca.gov.
- Volume Control Type: 100W Impedance Matching Slider Style
- Power Handling: 100W Peak; 50W 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
View Product Information
31 Questions asked
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Bill • 12/17/2019, 2:17:43 PM
I have 9 sets of remote speakers attached through zone 2 on an Onkyo receiver. All of the speakers work fine except for one set, where I just installed the volume control kit. At both the 8x or 16x switch setting, I can barely hear through the speakers when the volume on the control kit is turned up all the way. This also was true with the last volume control kit. I have checked the connections and they are correct. Any suggestions? Thanks.
Customer Service • 12/17/2019, 2:17:43 PM
Hi Bill:
I did not see any mention of a External Amplifier or Speaker Selector as part of your system. Can you let me know a little bit more about your system. Sounds like you have a lot going on.
tim@osdaudio.com
TL/4501
John S Alcorn • 12/17/2019, 2:17:43 PM
Hi, folks,
I was just online with one of your reps to discuss this topic, and got cut off (by him?).
I want to connect 2 pairs of 4 ohm speakers to my amp; one pair to Speaker A outputs and one pair to Speaker B outputs. I am assuming that I would use one VS100 control for each pair of speakers (confirmed by your rep).
Here are my questions:
1. Consider only Speaker A outputs from the amp. If I hook this to your VS100 and one pair of 4 ohm speakers, how should I strap the control?
2. If I am supposed to strap the control for "1/2x", then what would the impedance be that the amp sees, if I connected a pair of 8ohm speakers? (I am guessing 8 ohms?)
3. If I am supposed to strap the control for "1/2x", then what would impedance be that the amp sees, if I connect a pair of 4 ohm speakers? (I am guessing 4 ohms)
4. If your answer is that the amplifier 'sees' 8 ohms in each case, what mechanism is used to automatically sense the lower 4 ohm impedance load of the 4 ohm speakers and somehow adjust the impedance seen by the amp, with no change in strapping? If that is being done, then why not automatically sense and adjust for every additional pair (no straps!)? Is there such a thing as a dynamically adjusting transformer? I would think this would take real smarts (costing real $$$), so this doesn't seem to make sense?
5. If the reality is that, if strapped for "1/2x", a pair of 8ohm speakers will load the amp with 8 ohms, ea. and a pair of 4 ohm speakers will load the amp with 4 ohms, ea. (because the control is strapped the same for each), then, can I present an 8ohm load to the amp by strapping your control for four pairs of speakers instead of "1/2x"? (I am thinking the answer is probably, 'yes'?)
If you can tell me how to deal with the 4 ohm problem, I am waiting to buy. By the way, it would be helpful if the little installation sheet for this control covered this topic explicitly. The chart on that sheet only covers 8 ohm speaker pairs and multiples thereof...
Thanks for your help!
Best Regards,
John S. Alcorn
Tel: 864-972-3702
Customer Service • 12/17/2019, 2:17:43 PM
Hello John:
I am sorry for the confusion. Most impedance charts are based upon 8 ohm loudspeakers with 8 ohm Amplifiers or eight ohm speakers with 4 ohm amplifiers. So when considering 4 ohm drivers to work with an 8 ohm amplifier you have to calculate each 4 ohm loudspeakers should be considered as two 8 ohm speakers. There used to be a 1X setting before we combined it with the 2X (now 1/2x). It was basically a pass through with no impedance matching. So someone figured we would just combine the 1X and 2X to just a 1/2X to simplify things. In your case if you have the VMS100 on Speaker A and a 4 ohm speaker set to 1/2X you multiple the 2x times the 4 ohm of the speaker and get 8 ohms. So if you had a VMS100 connected to an 8 ohm speaker it wold be 2 x 8 or 16 ohms the amp sees. But since you are adding a second VMS100 and a pair of 4 ohm speakers to that you would get 8 ohms again (2X times 4=8 ohm). But if you listen to both A and B at the same time then you have two 8 ohm drivers in parallel so the amp would see a 4 ohm load overall. Can your amp handle a 4 ohm load? If you had (2) 8 ohm speakers with VMS100 set at 2X each so a 16 ohm load and you wanted to play them at the same time the load would be 8 ohm times 2 (16 ohm in parallel is half or 8 ohm). So in order for you to use (2) 4 ohm speakers each with a VMS100 impedance matching volume control you would need to set the Impedance at 4X on each Volume Control. Ironically by dropping the impedance from 8 to 4 your are asking for more current which increase power as well as heat. The weak link here is the VMS100 because it is rated at 50 watts rms/100 watts peak. This will cause the transformers to saturate causing distortion at lower levels. So I always recommend going to the highest value (either our VMS300, SVC300 or OVC300) especially in your application.
It can be confusing, but it is better to error on the safe side (higher Impedance)
Good luck
TL/4681
Tom Morton • 12/17/2019, 2:17:43 PM
I purchased 3 VMS100 controls to control 3 pair of 8 ohm speakers. All will be running off a basic 4 channel stereo amplifier. 4 speakers will be 1 indoor zone and 2 speakers will be 1 outdoor zone again each pair with its own volume control. What impedance setting do you recommend for each VMS 100?
Thanks
Customer Service • 12/17/2019, 2:17:43 PM
Hi Tom:
Safe setting would be 4x for all three VMS100. Especially if you are using a standard 8 ohm Receiver.
TL/4886
lee peoples • 12/17/2019, 2:17:43 PM
I've had this slider control for about 5 years and it has been working well except that recently i've noticed one of the channels (left or right speaker) cuts out from time to time. If I move the slider up and down it both channels come back on. Is there a way to fix this - blow out with compressed air, lubricate with silicone grease / WD-40 or something? Or should I just replace?
Customer Service • 12/17/2019, 2:17:43 PM
Hi Lee:
I can see blowing it out with compressed air. But would hesitate with the other options. I would contact OSD Audio customer service directly and talk to them. One to ask if they can check with the internal; technician on what other solutions there might be. Or think about replacing the current units where we can give you a replacement deal.
TL/4996
andre • 12/17/2019, 2:17:43 PM
Hi there, I'm using a Niles SI-1230 Systems Integration 12 Channel Power Amplifier using 30 watts RMS per channel into 8 Ohms, powering 6 pairs of Yamaha speakers 110 W;Impedance-8 Ohm and using this volume control for each pair, should I set the impedance to 8?
Customer Service • 12/17/2019, 2:17:43 PM
Hi Andre:
Since each speaker is connected to a dedicated Amp there is no need to worry about impedance matching. The impedance settings on the VMS100/300 are 2X, 4X, 8X and 16X. These numbers refer to the number of 8-ohm connections you have to a single stereo amplifier and in your case, you only have a single 8-ohm pair connected so 2X should be the choice. The question I have for you, have you already installed all the VMS100? Please let me know because there are other options I could recommend. tim@osdaudio.com
TL/5053