Voltage controlled amplifiers, or VCA's as us modular synth nerds call them, are an incredibly important part of any Eurorack setup. There is even a common saying that 'you can never have too many VCA's', and I tend to agree with that since I run out of them all the time. So in this post we're going to do the math on some popular and available VCA modules to figure out the best budget / most cost effective Eurorack VCA module.
If you're new to Eurorack, VCA's are basically the 'glue' that holds any patch together. When you want to apply an ADSR to an oscillator to control the contour of the volume envelope you can't do that directly, typically you'll plug the oscillator into your VCA's audio input and then plug your ADSR into the VCA's CV (control voltage) input. Aside from controlling volume envelopes you can also use VCA's to use control voltages to modulate other control voltages.
First of all I want to point out that despite VCA's being a very simple utility module, they aren't all created equal. They can have attenuators, switch between linear and exponential, or even dual function as mixers (also they can also be different sizes, and in Eurorack size costs money). We're focusing on cost / VCA and HP / VCA here for the most part, but i'll also mention some features as well.
Last thing before we dive into the numbers I want to emphasize this is for popular modules available through most modular retailers. Popular is very subjective and was based off of if i've seen or heard of it before and thought it was worth comparing.
Here's the data (again, in case you're new to this HP is the amount of horizontal space a modulate takes up in a rack):
The big winner here is the Doepfer A-130-8 Octal Linear VCA (link), absolutely crushing the competition in both cost per VCA and HP / VCA. I'm planning on grabbing one of these for a cost effective way to upgrade the total number of VCA's in my rack, however it's not all good news.
Not does this module not have any knobs to attenuate incoming signals, its only a linear VCA and absolutely zero bonus features like functioning as a mixer. This is 8 super basic VCA's crammed in a small size. If you know you just need raw linear VCA's, this is the best way to go. Using linear VCA's vs exponential VCA's is often just personal preference, but many people claim to use exponential VCA's for audio and linear for CV - however, it is common for envelope modules to already output exponential curves meaning an exponential VCA can give you a 'doubling' effect.
When it comes to HP / VCA's the 2HP VCA Linear (link) came in 2nd place, but its somewhat in the middle when it comes to cost / VCA. These are great for when you only have 2HP available but in raw cost and value its not the way to go especially because it can't dual function as a mixer or switch between response curves. I own several of these because they're relatively cheap and easy to buy more of them when you need them, you don't have to commit to a big upgrade like quad VCA's but they still have an attenuator knob to control how much signal goes through.
In my opinion the best modules to choose for most people are in the middle of this list. The Intellijel Quad VCA (link) and Mutable Instruments Veils fall relatively average on both cost per VCA and HP per VCA on this chart, but both of these modules have bonus features that make them more worth their price to me. Both of these can change their response curve from linear to exponential, both have offset controls which allows them to function as a mixer, and both of these have attenuators to control the amplitude of the control voltage signal.
Currently I own 2 of the Intellijel Quad VCA's but none of the Mutable Instruments Veils, also the Intellijel version has extra 'boost' switches. For these reasons i'm picking the Intellijel Quad VCA as the best buy but i've personally used it and for having that one additional feature. Either of these would make fantastic options though.
Overall Best Budget VCA: Intellijel Quad VCA - $189
Most Cost Effective Basic Linear VCA: Doepfer 1-130-8 - $90
This isn't to say that the rest of these modules are bad, but for various reasons I wouldn't consider them budget friendly. For example...
- The 4MS VCA matrix is a relatively unique approach and its massive at 26HP, and space costs money.
- The Behringer 130 is the 3rd cheapest module on this list but with only 2 VCA's it was one of the worst in HP/VCA and had a bad cost/VCA.
- The Roland System-500 Dual VCA is both large and expensive per VCA, it seems like they're relying on legacy and brand recognition to justify the price tag instead of value.
The Befaco Hex Mix VCA is an honorable mention because it fell slightly higher in the middle with Intellijel Quad VCA, Mutable Instruments Veils and 2HP VCA Linear. However if you have the tools and the time this module is available in a DIY version for a substantially cheaper cost and may be the best budget option.