All You Need to Know About 70V Volume Controls

Understanding and Wiring 70V Volume Controls: A Comprehensive Guide

This blog delves into the details of 70V volume controls, providing valuable insights into their functionality, wiring, and applications to best suit your audio requirements. Whether you're installing a commercial sound system or seeking a better understanding of in-wall volume controls, this guide will offer you essential information.

How Does a Speaker Volume Control Work? Speaker volume controls work similarly to dimmer switches for lights. Just as a dimmer switch allows you to adjust the brightness of a light, a volume control lets you adjust the audio level of a speaker. In 70V systems, these controls are especially useful for managing the volume of individual speakers or groups of speakers without affecting the entire system.

While there are both 8-ohm and 70V volume controls, this blog focuses solely on the latter. The 70V volume controls are commonly used in commercial audio setups. A key aspect of 70V volume controls is the built-in transformer, which enables the volume control to adjust the audio level without distorting the signal, ensuring clear and consistent sound across all speakers. For example, the AT100D decora volume control from AtlasIED is a popular model that fits into a standard single-gang wall box. Other manufacturers, such as JBL Professional, Lowell Manufacturing, and Pure Resonance Audio, also offer reliable options for 70V volume controls that can come with a decora wall plate or stainless steel wall plate.

Creating Multiple Audio Zones with 70V Volume Controls 70V volume controls offer a significant advantage in creating multiple audio zones within a single system. This flexibility is particularly valuable in environments like restaurants, offices, or retail spaces, where different areas require different audio levels.

For instance, in a restaurant, the main dining room might need a louder volume than the kitchen or restrooms. By wiring each area with its own audio volume control, you can easily adjust the sound to suit the specific needs of each space. Additionally, you can mix and match different types of speakers, such as ceiling speakers, wall-mounted speakers, or subwoofers, all controlled via speaker volume controls within the same system.

Whether you're dealing with a small office setup or a large commercial space, understanding how to wire and configure these controls ensures a seamless and customizable audio experience, allowing you to get the most out of your audio system.

How to Wire an In-Wall Volume Control for Speakers One of our most frequent questions is how to install volume controls correctly. While wiring an in-wall volume control for speakers may appear challenging, it becomes easier with careful attention to detail and the right approach. Here's a step-by-step guide:

1. Understand the Wiring Configuration
   Each audio volume control has a set of screw terminals labeled as IN and OUT. The IN terminals should be connected to your amplifier, while the OUT terminals should be connected to the speakers. Maintaining consistent polarity (positive to positive, negative to negative) is crucial throughout the wiring process.
2. Understand the Layout
   The goal is to wire the wall volume controls so that each one only affects the designated speaker(s), similar to how a kitchen light dimmer should only control the lights in the kitchen and not the lights in the bedroom.
3. Wire the First Volume Control
   Connect a wire from your amplifier to the IN terminals on the audio volume control. The wire includes a positive and a negative cable, so make sure to connect each cable to the matching terminal on the volume control. Then, run another wire from the OUT on the volume control to the speaker, ensuring that the positive and negative cables are correctly aligned.
4. Adding More Zones
   If you have multiple zones that need an in-wall speaker volume control (i.e., different rooms in a restaurant or office), similar to 70-volt speakers, you can daisy chain volume controls. If you have multiple speakers in a single zone, you can parallel wire them to a single speaker volume control. This means running a wire from the first control to the next, and so on, while maintaining the correct polarity throughout. Using the "IN" side of the control is crucial when adding new zones to prevent one control from affecting another. This method allows for consistent volume adjustment across all speakers in that zone.

Best Practices and Tips When wiring multiple audio volume controls, it's important to keep several key points in mind.

1. Avoid Excessive Home Runs
   A "home run" refers to running a separate wire from the amplifier to each speaker volume control. While this approach can work, it quickly becomes cumbersome, especially in larger setups with numerous zones. Instead, daisy chaining the controls is usually more efficient and less prone to wiring errors.
2. Watch the Wattage
   Each 70V volume control has a specific wattage rating that determines the maximum power it can handle. For example, the Atlas Sound AT100D and the Pure Resonance Audio VC100W decora volume controls are both rated for 100 watts. On the other hand, the Atlas Sound AT35 stainless steel volume control is rated for only 35 watts, while the Pure Resonance Audio VC50S is rated for 50 watts. It's important to ensure that the combined wattage of the speakers connected to the in-wall volume control does not exceed this rating. Exceeding the wattage can lead to system failures or reduced audio quality.
3. Properly Manage Polarity
   Always double-check that the positive and negative wires are correctly connected at each point in the system. Miswiring can damage the equipment and cause poor performance.

Understanding how to wire and use a speaker volume control can significantly improve the flexibility and functionality of your audio system. Whether you are setting up a restaurant, office, or commercial space, the ability to control audio levels in different areas ensures a comfortable and customized listening experience for everyone.

Pro Acoustics offers a wide range of 70V in-wall speaker volume controls and other audio equipment to suit various needs for those looking to install or upgrade their audio systems. We're here to help you design and implement the perfect system for your needs. Contact us at (888) 256-4112, visit our website at www.proacousticsusa.com, or email us at sales@proacoustics.com.

Check Out The Full Video Transcript
On this week's Pro Acoustics Tech Talk episode, Nathan and Coltin discuss 70V volume controls—how to wire them, control them, and use them to meet your needs.

Hey everybody, thanks for joining us for another Pro Acoustics Tech Talk edition. I'm Nathan. I'm Coltin. And we are back again here at our Salado, Texas location. We will talk to you guys more about volume controls, particularly 70-volt volume controls. We've done a little bit of 70-volt talk in one of our prior videos, but we want to dive in a little deeper, show you how it works, show you how to wire it up a little bit, and give you just a little bit more oversight on how this all works.

All right, Natha,n volume controls. We have a good visual representation of what's about to happen going on behind us. We're going to show you how to wire them. I always get asked how they get involved with the entire system. How do we control one area and not affect the other areas' volumes? So, let's do the breakdown. Give it to me straight. What's the purpose of volume control, and what do they do?

You got it. You got it. So, there are eight-ohm volume controls and then also 70-volt volume controls. 8-ohm volume controls tend to be used in home audio applications. Check out one of our other videos for more info on home audio versus commercials, but we're talking all about 70-volt volume controls here. Why does it matter? It matters because there is a transformer on the back of some of these volume controls. Actually, almost all of them. And the electrical voltage matters. So, I have an Atlas Sound AT100D in my hand. It has a white faceplate to go into a single gang box on a wall, just like your light. They also make a stainless model. We also have some volume controls from Lowell Manufacturing.

A handful of other manufacturers make some of these 70-volt volume controls. Awesome. Most of the time, they click with each adjustment. Typically, you get either a dB or 3 dB bump each time you click it. The idea is you run from your amplifier into the volume control and out of the volume control to the speaker. So, you can think of it just like a dimmer knob for your lights to where you come from your breaker panel into your dimmer knob out of the dimmer knob to whatever lights you want to control. Obviously, in this kind of scenario where you might have multiple volume controls when done correctly, the dial will only adjust the speaker you want - when done correctly, just like Coltin's house. When he turns the dial on the wall in the kitchen, it does not turn down the lights in the bedroom.

We don't want it to be that way. We want to ensure the dials are wired to the appropriate speakers you want to control. So, whether it's stainless or white decora style, you've got to wire them correctly. Whether they're in a rack, they also make rack volume controls from some of these same manufacturers, so you can have all this done in a nice, neat little rack plate, or whether it's in the wall, it's important to wire these correctly. Importantly, I'm going to go ahead and just let everybody know for visual purposes the back of every volume control has a handful of screw terminals on a Euroblock. Each of those will correspond to whether it's an attenuated or an unattenuated signal; those are big words that I'll explain in a little bit, but basically, is it affecting the audio volume or not? Then, it has positive and negative connections.

So, each of these volume controls is drawn for us by our wonderful web team. Each has an amp positive and negative IN and a positive and negative speaker OUT. Those are the labels on the back of this little bitty Euroblock plug I'm holding up here. For our intents and purposes here, anytime I color to the top of the volume control, that will be the amp IN, positive or negative. And then when it's coming out of the bottom as a speaker OUT positive and negative. It is very important to read what it says on the volume control when you're putting the wire in. Yup. So, from here, we have our makeshift restaurant or office or whatever it is, where we have a mixer amplifier, hopefully, a Pure Resonance Audio MA series mixer amplifier, or any other manufacturer, feeding from the mixer amp into multiple volume controls to feed to the speakers.

So, right off the bat, how do I wire this? So, you always have the option of using 70-volt audio to run multiple home runs. What's a home run? Just baseball. Exactly. It's all about Albert Pujols and the boys. No, for home runs, we're talking about running just one wire to either one speaker or one volume control. You can run a wire from this volume control if you want to. And when I say a wire, I mean a cable with two wires inside a positive and negative. You can run from there to there. You can run from there to there. You can do an individual home run for each volume control if you want. The problem is, I did a doctor's office the other day that had 24 individual rooms.

That's 24 home runs. It's 24 positives and 24 negatives. It's not a good thing. And what am I going to do with 24 cables? So, at that point, if you're an electrician or somebody more electrician-minded, you can take all 24 of your positives, tie all those together, all 24 of your negatives, and tie those together using proper electrical safety standards because, once again, audio is electricity. You can tie all those together. You can build a terminal block and do that kind of thing, but I would advise against it. It's not the easiest. It's too many cables. It's too possible for a stray wire to fall out of a wire knot or something like that. And it's generally not a good practice.

So it's okay if you do a couple of individual home runs, maybe all the volume controls on the east side of the building and all the volume controls on the west side of the building. That's a good way to look at that, and you can do what I'm about to do here, basically times two, but the idea is instead of doing all those home runs, like when we were doing 70-volt speakers, remember we would run them in parallel one after the other. Instead of paralleling our speakers here, we will parallel our volume controls because we want to get these volume controls in the mix. We're going to daisy chain volume controls one after the other. It's extremely important to always keep positive to positive and negative to negative when you're doing this.

So once again, as I mentioned before, the top portion of our volume control is going to represent the amp IN. That's unattenuated. That's just the cable coming in and then the cable coming out—no adjustments made whatsoever. So, to go to our first volume control, I will come out of my positive terminal and go into the amp IN on my first volume control. I'm going to repeat that same thing with my negative. From there, I will come out of the speaker OUT, which is the attenuated side. This means that it's adjusting the level. And come down into the positive terminal of the speaker. Positive to positive and negative to negative. Then, I'm going to do the same thing with a negative.

Speaker one is done. That dial controls that speaker. Let's say that it can be my patio, and that could be my inside. That could be my outside. That can be room one at the doctor's office. That can be whatever I want. To be clear, if you had multiple speakers on that patio, it would bounce one after the other. If I wanted to add more speakers, I could come down here, do another one, and jump off the negative. Do another one on down, all the way down. All intents and purposes forever. Most people don't, but that is the idea there. That gets us done with zone one because it's the same input source coming from this amplifier, but it's a different volume.

So, we will move on from zone one to zone two. What do I do? The last thing you want to do is to come out of the speaker OUT over there. Cause at that point, this dial controls that dial, which means that if you're in Coltin's kitchen, you're turning down the lights in Coltin's bathroom. You don't want to do that. So, instead, we will come out the amp IN side. So, we will either splice from this wire here or come out of the same terminal and from that volume control to the amp IN from the next volume control. We're going to do the same thing with black. And again, positive to positive, negative to negative. It's essential to pay attention to your appropriate polarity, both positive and negative. From there, we'll come out of that volume control on the speaker OUT. This will be on the attenuated side, which lowers or raises the volume, and we will go into the speaker's positive terminal.

We're going to do that again.

You guys probably get the hang of it now, but I will draw the rest for the folks at home. And then do it again with your negative.

While he's doing that, the same concept must apply if you have multiple speakers in multiple zones. The same concept applies if you have four speakers on that first volume control, then ten on the second, and you're going off one speaker off the next. So, if this looked like 10, this looked like 4, this looked like 15, and it keeps going and going positive to positive, negative to negative.

You can definitely always have zones with more speakers or with fewer speakers. So, in our restaurant scenario, this can be our main dining room. This might be a hundred-watt volume control. It might be a 200-watt volume control. We might have 20 speakers on this one, but say this is the kitchen where we've only got two speakers, and say this is the restrooms, and then this is private dining. We don't have to have an equal number of speakers on each volume control. When wired in this direction correctly, paralleling your volume controls one after the other, always using the amp IN or the unattenuated side, we can do as many volume controls as we need in this scenario. We can also mix and match ceiling speakers, wall-mounted speakers, pendants, speakers, subwoofers, or anything else, as needed.

This is a great way to create multiple volume zones inside your 70-volt system, and it's also very inexpensive. Most of these volume controls in a hundred-watt model may run anywhere from $25 to $50 or so depending on whether you want the décor look—the white plate, the cream plate, the pretty black plate—or stainless, which tends to be a little bit cheaper.

And then we also have lower wattage volume controls. So, each volume control has its own wattage rating. These are AT100D, 100-watt attenuators from Atlas Sound. That means it's rated for up to a hundred watts on the speaker output side. It doesn't matter if more wattage goes to the amp input side. It's just based on the output side. So, the sum of these speakers is what matters about being less than a hundred. So, you want to ensure that you stay within the wattage rating of the volume control itself.

Hopefully, this makes sense to you guys. If it doesn't, and you have questions, shoot us a comment below. Like the video, let us know that you're watching now. Feel free to subscribe, or you can always give us a call. Our 800 number is (888) 256-4112. You can visit us online at www.proacousticsusa.com. We have several packages with pendant speakers, in-wall or on-wall speakers, and in-ceiling speakers with volume controls and without, available on our website and our Amazon store. If you want to shop there, by all means, or if we can help go over anything for you or put together a custom package, we can help get you the right number and type of speakers that you want with the right volume controls and walk you through how it all goes together. Just reach out to us and let us know how we can help. You can reach us at sales@proacoustics.com. And don't be a stranger. Let us know what we can do to help out. Like us below, subscribe, tell your friends, and stick around for our next video. Until next time. I'm Coltin. I'm Nathan. See you.