How To Increase Inputs On Your Audio Interface

Focusrite Scarlett audio interface. Used for DAW's.

When people first get into music production, one of the first investments they’ll make is in a DAW (digital audio workstation) – this means they will buy an interface, some software, and some monitors.

In my case, I bought an MBox 2 Pro Factory with ProTools LE 7 over 10 years ago. It’s a great way to start, and today it’s significantly cheaper to pick something up that is newer and better.

If my memory serves me correct, I paid around $700-$800 CDN for my MBox 2 and the software which came with it. That was brand new. Today you can get something similar or better for half the price. One comparable interface today is the Focusrite Scarlett 6i6, which is only $359 CDN.

However, you may find it won’t take long before you’re trying to figure out how to expand the number of simultaneous inputs you have. Especially if you are trying to record drums, record a band live off the floor, or use multiple microphones on the same source to blend and shape your tone.


Spencer making a frustrated face extra holding XLR and TRS cables in his hand while all his DAW channels are all used up behind him.
Need. More. Inputs….

I got the idea for this post because I’ve always wanted to increase the number of inputs for my DAW. However, I was never able to do it because it always seemed like I was going to have to spend thousands of dollars in upgrades to do it.

I recently started over with my research, and I am kicking myself because I can’t believe I didn’t figure this out a long time ago – and it’s dead simple.

In other words, this is the post I wish I had found a long time ago…

This post is going to cover two things:

  1. Two ways you can increase the number of simultaneous inputs on your DAW.
  2. If you are in the market for your first DAW (or replacing your old DAW), how to plan ahead. This way when the time comes, you can increase the number of simultaneous inputs on your DAW quickly and easily while minimizing your expenses.

Lastly, if it interests you gear geeks, I have a fairly comprehensive list of my gear you can check out.

Increasing the number of simultaneous inputs on your DAW

There are numerous ways you can do this and I won’t be able to accurately cover all the possibilities. Frankly, some methods of doing this can be highly dependent on your audio interface and the software you use. So there’s no sense in trying to cover all the different software and devices.

I will only focus on two ways that will likely have the greatest use to most people while being less dependent on specific audio interfaces and software.

Two Quick Disclaimers


Generally speaking, these methods should be relatively universal. More specifically, one method universal to Mac users, while the other should be universal to almost everyone.

However, there are always exceptions dependent on what your hardware and software is. I have only ever really used Pro Tools and Digidesign/Avid hardware so I will be writing from that perspective.

If you use a different DAW such as Logic, Cubase, Reaper, etc., or another interface, then these methods should still work the vast majority of the time. However, I make no guarantees.


This post contains affiliate links. This means if you click on one of these links and make a purchase you will not be charged a penny more, but I might receive compensation. You can learn more by reading my Affiliate Disclaimer.

1. Create An Aggregate Device To Increase Inputs (Mac Only)

Screenshot of Macintosh Audio Devices window when setting up and aggregate device.

If your DAW is Mac based, then one work around is to create an aggregate device. In the most basic sense, this allows you to combine two audio interfaces so that your Mac sees them as a single device.

Unfortunately, it is not quite as simple as plugging both devices into my firewire ports on my Mac. But it is pretty close.

Creating an aggregate device is one way to “trick” ProTools into thinking you are using one audio interface. In my case, this would allow me to combine the 4 inputs on my MBox with the 8 inputs on my Digi 003 – giving me a total of 12 inputs.

This is especially useful for older ProTools LE systems such as mine. These systems will only communicate with one audio interface.

A Known Catch Using Aggregate Devices

However, I did find a catch. My Digi 003 can not be used as an aggregate device. Despite my research telling me this, I thought I would try it anyways. Sure enough… no dice. The Digi 003 will not be an option when combining devices. So if you are running a Digi 003 or 002 series, you’re probably out of luck. But who knows? It’s not hard to do, so try it anyways.

That being said, if you have two or more audio interfaces that don’t have an optical output (see next method), such as two MBoxes, then it is definitely worth exploring. It should work just fine in most cases.

So for me, creating an aggregate device using my MBox and my Digi 003 Rack Plus was not an option. But it could be for you.

Other useful links on aggregate devices:

2. Use ADAT Lightpipe To Increase Audio Interface Inputs

Focusrite Scarlett 18i8 - rear view.
Focusrite Scarlett 18i8 rear view with Optical Input Circled

ADAT Lightpipe is a standard for transferring digital audio between equipment. This is the method that will work for almost anyone, as long as you have an optical input on your audio interface. You will be able to add up to 8 channels of digital audio inputs to your DAW.

I always thought ADAT was old technology used to hook up old gear like digital tape machines. Wrong.

In my case, my MBox 2 Pro does not have an optical input or output, therefore I cannot do this with the gear I have presently. However my Digi 003 Rack Plus does. So, for a relatively minimal investment, I can expand my system to 16 inputs, and you can do something similar.

How To Hook Up ADAT Lightpipe To Your Audio Interface

The video below is an older video, so he’s using some older gear and software. However, the only thing that will likely vary to any degree is how you set up the two devices to sync together. That will be specific to your DAW software. In this case he is using an older version of Pro Tools LE. Otherwise, it’s probably a lot easier than you thought.

There are other videos out there if this isn’t your specific DAW software. Just search for ADAT and your DAW software. You may also need to include your audio interface (or a similar one).

Planning For Future Expansion With Your Audio Interface

So, you are looking at getting your first audio interface or you are looking to upgrade your old one. If I were to give you one piece of advice, it is this:

Make sure your new device has an optical connection for ADAT

ADAT will be the easiest and cheapest way to expand up to 8 additional inputs in the future, should you choose to do so.

Not everyone runs a Mac and not every device can be used as an aggregate device on a Mac. In my opinion, setting up an aggregate device is kind of a “hacky” way of doing this.

However, ensuring you have ADAT on your new audio interface will ensure your DAW can be expanded using reliable, industry standard methods.

In my situation, purchasing an 8 channel preamp with ADAT now gives me up to 16 inputs – and I can do it for as little as $300 CDN. If you have a 4 input DAW with ADAT, you can expand up to 12 inputs for your DAW.

The number of inputs your DAW can potentially have will depend on your audio interface, and what you decide to expand it with. However, I think you will have a hard time getting up past 16 inputs without completely upgrading your whole system – and that can be big money.

Audio Interface With ADAT

Naturally, some of you may be wondering what some good audio interfaces are if you want to plan for future expansion. Maybe some of you already have an audio interface with ADAT and now you want to know what to expand it with.

Just to be clear up front, audio interfaces capable of ADAT will be more expensive than ones without. However, I personally think it is worth the extra cash if you plan on being able to expand the inputs of your DAW. This list will focus on audio interfaces that are under $500 CDN, and between $500 – $1000 CDN.

Full disclosure: I’m a big fan of Focusrite. They have a very well known reputation for making high end products, and they are still affordable.

Audio Interfaces with ADAT Under $500CDN

Behringer FCA610

Behringer FCA610 DAW audio interface
Behringer FCA610

The Behringer FCA610 is probably the cheapest audio interface for your DAW that is capable of ADAT. It has two mic/line inputs on the front, plus an additional two line inputs on the back. They say it is compatible with several popular DAW software, as well as Windows or Mac.

Check price of the FCA610 on Amazon

Behringer FCA1616

Behringer FCA1616 DAW audio interface
Behringer FCA1616

The Behringer FCA1616 takes it up a couple notches as far is inputs and outputs are concerned. It has four mic/line inputs on the front with an additional four line inputs on the back. This would be one of the cheapest eight channel audio interfaces you can get. So, using ADAT you can certainly expand your DAW up to 16 inputs.

If you are on a really tight budget, I would look at the FCA1616. However, if you are looking for eight mic preamps on your interface, keep scrolling. Since this only has four mic preamps, you will find you need some additional external gear to run more than four mics at once.

Check price of the FCA1616 on Amazon

Audio Interfaces with ADAT Between $500-$1000CDN

Focusrite Clarett 2Pre USB

Focusrite Clarett 2Pre USB DAW Audio Interface
Focusrite Clarett 2Pre USB

The Clarett series is more expensive than the Scarlett series from Focusrite. The biggest difference being in the preamps, to my understanding. The Clarett 2Pre USB is exactly as it sounds – 2 mic preamps and connects to your computer via USB. If you are prepared to sacrifice inputs for higher end preamps, then this is a great option for you.

You can use the two preamps on this for certain applications, then get a cheaper 8-channel preamp to connect with ADAT for up to 10 mic preamps.

If you want a few more preamps in the Clarett series, then there is a 4Pre version that is still under $1000 CDN. However, going for the 8Pre version will set you back around $1200 CDN. Very nice interfaces, but you do start to get up there in price.

Check price of the Clarett 2Pre on Amazon

Focusrite Scarlett 18i8

Focustrite Scarlett 18i8 DAW Audio Interface.
Focusrite Scarlett 18i8

The Scarlett 18i8 is one of the best places to start, in my opinion. I know I said the Clarett series has better preamps, but that’s not to suggest the preamps in the Scarlett series are weak by any means – they’re not.

This interface has four mic/line inputs in the front, and an additional four line inputs in the back – much like the Behringer FCA1616.

Generally speaking, it is a much higher quality unit over the FCA1616 in virtually every way.

Check price of the 18i8 on Amazon

PreSonus Studio 192 Mobile

PreSonus 192 Mobile DAW Audio Interface.
PreSonus Studio 192 Mobile

The PreSonus Studio 192 Mobile has a unique feature that makes it stand out to me. Not only can you expand it by up to eight additional inputs using ADAT, there is a second ADAT connection to expand it even further!

In other words, this audio interface is expandable by up to an additional sixteen inputs using two ADAT connections. So depending on your peripheral devices, you can run up to 20 mic/line inputs total. Not to mention it’s capable of a blistering 192kHz sample rate.

PreSonus is usually considered to be entry level or cheaper gear, but this unit is not one of them. They might of hit it out of the park with this interface.

Check price of the Studio 192 Mobile on Amazon

Focusrite Scarlett 18i20

Focusrite 18i20 DAW audio interface
Focusrite 18i20

Finally, we get to our first audio interface that truly has eight microphone preamps. Drummers rejoice!

Having eight preamps is typically considered a must if you are recording drums. Don’t get me wrong, it has been done with four in the past (Led Zeppelin anyone?). However, more often than not you are going to wish you had at least eight preamps to record drums.

Personally, if I was in the market for an eight mic preamp interface, this would be near the top of my list. As of the moment of writing this, it is priced competitively at $599CDN.

It’s also hard to find someone who doesn’t like this interface…

Check price of the 18i20 on Amazon

PreSonus Studio 192

PreSonus Studio 192

The Studio 192 is the full version of the 192 mobile mentioned earlier. This is getting up into pro level gear, however it makes this list because it fits within the price range… barely. This is likely going to be overkill for most people reading this, however it still makes the list!

This rack mount unit has all the same features of the 192 mobile, plus:

  • Integrated talk back mic
  • Ultra low latency
  • Expandable from 8 mic preamps to 24 using two ADAT connections

This is also the most expensive audio interface on this list. It comes in at about $999 CDN.

Check price of the Studio 192 on Amazon

ADAT Audio Interface Expansion (Preamps)

I felt like it would be difficult to go through all this effort on ADAT audio interfaces without discussing the hardware you can expand it with. So, if you have an audio interface with ADAT, here are some great options to expand the number of inputs to your DAW.

ADAT Expansion Hardware Under $500CDN

Behringer ADA8200

Behringer ADA8200 8 Channel Microphone preamp with ADAT
Behringer ADA8200

The Behringer ADA8200 is probably one of the most inexpensive preamp options for expanding your inputs. As of the writing of this post it retails at $299.99 CDN. It is pretty basic in it’s functionality but what more could you ask for at this price?

In fact, this is a slightly newer model than the one used in the video shown earlier in this post. This is definitely one of your best options for ADAT expansion if you are on a tight budget.

Check price of the ADA8200 on Amazon

ADAT Expansion Hardware Between $500CDN – $1000CDN

Focusrite Scarlett OctoPre

Focusrite Scarlett OctoPre 8 channel audio interface
Focusrite Scarlett OctoPre

The Focusrite Scarlett OctoPre is a great ADAT expansion option for anyone. Yes it is more expensive than the Behringer, but I personally think it’s worth it. It is a natural companion to the Focusrite Scarlett 18i20 interface mentioned earlier in this list. Even if you don’t have the 18i20, I doubt you will be disappointed.

For $549 CDN I just don’t think you can go wrong with this.

Check price of the OctoPre on Amazon

PreSonus DigiMax D8

PreSonus DigiMax D8 Mic 8 channel microphone preamp with ADAT
PreSonus DigiMax D8

The DigiMax D8 by PreSonus would fall into the same class as the OctoPre. They are both in that same price range and have similar capabilities.

The only thing I see as a possible issue with this unit is that they put the phantom power buttons on the back of the unit. If you are going to put this in a rack, talk about a major inconvenience. However, if that’s not a concern for you, then I would certainly consider the D8.

Check price of the DigiMax D8 on Amazon

Focusrite Scarlett OctoPre Dynamic

Focusrite Scarlett OctoPre Dynamic 8 channel microphone preamp with ADAT and analog compressors
Focusrite Scarlett OctoPre Dynamic

Confession time…

I am completely biased towards the OctoPre Dynamic, because I recently ordered one. You can expect an unboxing and demo video in the future when I get it.

Honestly, the biggest difference between the OctoPre and the OctoPre Dynamic are the built-in analog compressors on each channel. This was the selling feature for me, and the reviews on this preamp are phenomenal.

I have a really crappy & old DBX compressor that seems to be hit and miss. So, being able to slightly compress certain sources on the way in will be a huge help. Especially on vocals and DI’d guitars and bass.

Check price of the OctoPre Dynamic on Amazon

PreSonus DigiMax DP88

PreSonus DigiMax DP88 ADAT 8 Microphone PreAmp
PreSonus DigiMax DP88

The DigiMax DP88 is the most expensive ADAT expansion piece on this list. Like the Studio 192 audio interface, it is in that pro level category but barely makes this list based on the price. Like the Studio 192, it will probably overkill for most people reading this.

Since it is clearly intended to be a companion piece to the Studio 192, it’s not surprising that the price also comes in at $999 CDN.

Check price of DigiMax DP88 on Amazon

Conclusion: Expanding Your Audio Interface Inputs

If you are looking to get into recording or upgrading your system, I am willing to bet that it won’t take long for most of you to start wishing you had more inputs. I’ve been there.

If you are a Mac user and happen to have two audio interfaces sitting around, then creating and aggregate device could be the best option for you. However, it is kind of a “hacky” way of combining interfaces for more inputs… and it doesn’t work for all of them either.

Your best option is to use ADAT. By ensuring your audio interface has ADAT, you can save yourself a lot of headache in the future. In addition, ADAT is an industry standard method and it’s reliable. Unfortunately I don’t think many people are still aware of how useful and relevant it is. It has often been thought of as old technology that doesn’t really get used anymore. Myself included.

The moral of the story is, make sure you get an audio interface with ADAT.

Best ADAT Value Combinations

Personally, I think the best bang for your buck on an audio interface will be either the Focusrite Scarlett 18i8 or the 18i20. You get great quality preamps as well as at least four of them to begin with. That is a great start. Then since you have the ADAT already available on your interface, expansion is dirt simple. If you wish to add another eight mic preamps, you can do it for as little as $299CDN with the Behringer ADA8200 – and frankly, there’s nothing wrong with the Behringer.

However if your budget allows for it, I think the OctoPre Dynamic will be your best option for expansion. Again you have eight great preamps, plus analog compression on each channel.

So what audio interface would you go with? What ADAT mic preamps would you go with? Can you do it for under $1000CDN each?

The post How To Increase Inputs On Your Audio Interface appeared first on Calgary Recording.

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