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Eric Valentine PT. 2: The MPEQ-1 And UnderTone Audio's Future

Posted on September 9, 2014 by Eric There have been 0 comments


When Vintage King last caught up with UnderTone Audio co-founder and famed producer Eric Valentine, we talked about the birth of the brand and his start in the world of building gear. The focus of our conversation now turns towards UTA's MPEQ-1 rack unit, a Class A mic preamp and EQ, based on Valentine's original console design.

As UTA's product base shifts from consoles to outboard gear like the MPEQ-1, the ideal behind the products still remains the same. The focus remains on creating products that are uncompromising and fit Valentine's specific needs, all the while knowing that as long as there are others who require flexible gear, UTA will be around for years to come.

Having used the EQ already in the console, what made you decide to add a mic pre to the MPEQ-1 rack unit? What did you want to get from this piece of gear?

Consoles are extraordinarily expensive and there were a lot of people interested in the equalizer who just couldn’t afford, justify or want a whole console. It made sense to create a single channel so people could take advantage of the equalizer.

The way I really envisioned it being used is that we paired it with the mic preamp. Partly, because there wasn’t enough room in a single rack space for a stereo equalizer, so this gave it more space with the mic pre in there. It’s really a great capturing device when you’re recording into a computer. So if you have one of these things and you are using a small rig and just doing overdubs, everything will work well with this device. The equalizer can cover whatever you’re doing, whether its vocals, drums or bass, it can just do anything.

You can get the sound pretty much done as far as the mic pre and the voicing, or the EQ of it, all with this one device. It’s a one stop shop for capturing sounds and getting the frequencies balanced the way you want. That’s essentially the way I use this stuff in my studio.

What is the most essential element of a great EQ and mic pre? How did you bring those elements to the MPEQ-1?

My whole approach to recording is that I love to have a lot of control and a lot of flexibility. There a lot of people out there who don’t want that. They just want to have it narrowed down to one thing and I totally get that approach. My thing is I do vastly different styles of music, from bluegrass to hardcore punk rock bands, all kinds of stuff. I need equipment that can work in any context, so everything we design is massively flexible.

The equalizer can do anything I want it to do and because the transformers are passable, there are ways to drive the mic pre more if you want to get a more vintage, driven sound. The MPEQ-1 circuit has a volume trim on it, after the mic pre, so you can turn that down and turn the mic pre up to drive more if you want to. Our piece is done in a way that doesn’t change the sound of the mic pre and you can really get out of it want you want. If you need something pristine, you can bypass the transformers and it’s a huge open sound.


In the manual for MPEQ-1, you have notes on presets for all of the classic EQs including Neve and Pultec. What was the idea behind giving people these options from the start?

It was part of the process of creating the equalizer. It’s relevant to the shelf EQ function. When we were developing the equalizer, there was a certain Neve EQ that I liked the sound of. So, we looked at the circuit and checked how they did it and realized what they were using. They used to two filters together to create a shelf shape. Basically every EQ that has a shelf on it, the designer has to commit to a certain shape for that shelf.

When we did the initial prototype of the equalizer, we put a little trim pod in there so I could have some control over the blend of these two featured filters. As soon as I started playing with it, I realized, “This has to be a control on the front panel,” because it allows you to create any shelf shape you could want.

As we were developing the equalizer, I would go and try and emulate other EQs that I had around. I had a GML, an API and an old Neve, and I tried to replicate them exactly.

A lot of people, somewhat naively, will take two equalizers and put them at the same settings on the faceplate, put them both at the 10k shelf, boost them both 10db and think they should sound the same. How different designers interpret what those different shelves and boost are completely different from one another. You listen for the difference, they sound completely different and people think, “Oh the API shelf is so much better than the Neve shelf” for that certain application. In reality, the boost they are doing is not even remotely the same.

I just thought it would be real useful to people because the controls are kind of complicated on the MPEQ-1. If I know I like these settings on an API, I can set the shape control here and the cue control there, I can pick a frequency and boost and it will have the same exact character as API. It’s really, really close.

Are you still planning on bringing out a 500 Series version of the EQ at some point?

We are definitely are going to make that happen in some form or another. It’s going to be incredibly challenging. Honestly, it’s sad that the world has fallen in love with the 500 Series. You ask any designer and they fucking hate it. It sucks. The limitations on a 500 Series Format are ridiculous. It’s such a drag, but it’s definitely possible to have the features of the equalizer in that format.

The challenge is that the circuitry is Class A, it draws a lot of current, it takes up a lot of space and there is a lot of heat. That’s part of what Class A is all about. The Undertone stuff is much more efficient than other Class A circuits, but even with that, it’s still going to be challenging.

What’s going to get figured out is how much Class A can be preserved in the 500 Series version. That, at end of the day, will be the difference, and we'll try to keep it as pure as the original, but there are going to be some places we can use the discrete Class A gain stages the way we did on the rack mount. If you really want the pure thing, you’re going to have to get the 19-inch rack mount. The 500 Series will sound great, but it won’t be quite the same thing.

What else is coming down the pipeline for Undertone?

I’m trying to get the Unfairchild back on track. All of this stuff mostly ends up being a time issue for me. Now that I have my two favorite consoles in the world in my studio, I very much want to spend my time using them. So it’s been challenging to have this all going on. Right now, we’re building the last two Undertone consoles. I just don’t have time to do it anymore.

Also, The MDI-4 is a 1RU 4 channel mic pre-amp. It will be available in about a month. It is the same mic preamp that is in the MPEQ-1 but has some cool extra features. The output transformer is bypass-able via a switch on the front panel, instead of having an alternate output on the back. There is a "Load" switch that adds extra harmonic coloration to the circuit. There is an output pad switch that drops the level by 10dB so you can hit the mic pre harder and not clip digitally on your DAW. Every channel has an amazing DI input as well.

So that’s going to happen. The 500 Series is going to happen. In lieu of the consoles, I’m envisioning a smaller summing mixer type product that has the features that are addicting from the current collection of summing mixers out there. When I’ve looked at that stuff, there are some really essential things that I think need to be available. I’m going to try and design it so that it’s really modular. There will basically be a bunch of Lego parts that people can put together in various configurations and they can figure out how they want to do that.

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