Wednesday, June 1, 2011

An Interview with Rick Holt- The Force Behind Frequency Central

Rick is the sole driving force of Frequency Central, he makes plenty of mind blowing custom pedals as well as sub-mini and 12ax7/au7 tube amps (like the one above). I reached out to Rick for an interview to tell us more about his unique creations and maybe provide some guidance to all you budding DIY folks out there. Read on for more information on Frequency Central!

Tell us a little bit about yourself.

As a kid I used to dabble with electronics, building noise makers and such, and screwing around with cassette recorders, splicing tape loops and using a couple of recorders for sound on sound recording. I was into noise way before I could play a note. Moved onto analogue synths, then the world went digital – bad move world! I was always a wanna-be guitarist, then I joined a band in which the requirement was to reproduce the recorded sound live, which meant I ended up playing guitar as well as keyboards. I started buying a few pedals, then thought it might be fun to build some……

What inspired you to start Frequency Central?

It kind of happened by accident. I designed the Murder One submini tube amp a few years ago, for myself really. I got a couple of requests for builds through the DIY forumswhich soon turned into a regular stream. Then I did the Superfly submini tube amp, more power than Murder One but even smaller – same thing – people asked for builds. I’ve never consciously designed a product for sale, it all comes out of my personal sound experiments. I never had a business plan as such, I  just happen to put things together that appeal to people . More luck than judgement if I’m honest.

The Murder One
Your circuits are all very well thought out, neatly wired, and some are very complex (like the Sonic Death Ray 14 stage phaser). How did you learn to design these unique circuits and execute them so neatly?

The older Sonic Death Ray design

My background is in analogue synths. I bought a small Roland 100m modular system some years ago and my brother (an electronics engineer) encouraged me to build some extra modules for it. The more modules I built, the more I learned. I ended up designing a few custom modules and eventually a whole synth from scratch, it just sort of came naturally. Compared to building synths, building pedals is child’s play. I find that I tend to look at pedal design in the context of a kind of small modular synth dedicated to guitar processing. As for the neatness, I just do it the best I can, good assembly processes mean less debugging of the finished item.

The Sonic Death Ray looks to be a very time-consuming build with 14 stages, why did you decide to go so far beyond what other manufacturers were doing? Would you mind briefly walking us through the steps of building one?

The new Sonic Death Ray design
Ah, the Sonic Death Ray. I went on a quest to find the ultimate ‘swooshy’ phaser pedal, built a number of different stock phasers but found I still wanted more. As I research the subject, it occurred to me that there were a number of unexplored avenues which could be implemented. Sonic Death Ray originally started life as a 6 stage, but the more stages I added the better it sounded. Finally I got up to 14. As there were now so many stages it made sense to add options for multiple regen taps. One day I found myself toggling the switch between odd and even stages and really liked the effect, so I added a sub-circuit with a second LFO to automate this process.

You also design submini and 12ax7/12au7 tube amps that are about the size of an effects pedal, where did this idea come from?

The Obsession II: A 12ax7/12au7 powered amplifier
I discovered submini tubes a few years ago – I was amazed that such things could exist! I became completely obsessed with the damn things – designed submini tube tremolos, vibratos, boosts, overdrives…….then I researched voltage multipliers and found that it was possible to generate hundreds of volts in a very small package from just a 12 volt power pack. A tiny amp was just begging to be made. Technically, it’s a challenge to fit it all together in such a small enclosure, but the results are well worth the effort. It’s great to have a really small low wattage tube amp around that you can totally crank up without breaking your ears.

What does the future hold for Frequency Central? Can we expect any more production model pedals or will you be sticking to mostly custom work? Any new amps in the works?

I’ve kind of decided recently that my niche is tiny tube amps and big complicated pedals. My next major project will be the Gemini Dual Core Phase Shifter. The idea is a Bi-Phase work-a-like, it’ll be based on the Causality 6 ( 2 more stages than a C4), and will have two phase cores that can either be configured in series or parallel, a total of 12 stages as there will be two Causalities inside. Two LFOs, but with the option to sync both phase cores to LFO 1.  I’ve also got plans to make the Time Machine delay more than just a one-off. I’m also planning a new multimode filter pedal – Space Lab, which will be basically a whole analogue synth but without the oscillators. As for new amps, I have three different models available right now, I feel that my range of amps is broad enough at the moment, but I’m still doing research as I really want to build a really super-powerful tiny amp at some stage in the future. It’s getting harder to find the time to execute new designs with the volume of pedals I’m currently building/selling.
A mock-up of the upcoming Gemini Phaser

The Time Machine Delay
Is there any type of pedal that you would like to build but haven't yet?

You know, I’ve never built a flanger! Keep meaning to, I have a couple of flanger PCBs here but just haven’t found the time yet. I just know that when I finally build one I’ll want to mod it all to hell and add many extra features.
The ultra-compact Superfly amplifier

What is your favorite pedal or amp that you have made so far?

Usually the one I’ve just finished building. I built a Superfly to order for a guy recently with a few extra features, it blew my Superfly away! Mine is one of the early ones – I tend to use each build as an opportunity to tweak and sometimes add new features. I think I owe myself a newer model Superfly when I get the chance.

Do you have a favorite graphic or finish that you have done?

I’m moving away from graphic image decals, though I still do them by request. My new thing is etched enclosures with simple and functional graphics. I just etched and painted an enclosure for an Atomic Clock modulated delay – easily my favourite so far. ;-)
My Atomic Clock, can't wait until it's done! Stay posted for a review!

Do you usually make your own pedals or do you have some non-Frequency Central ones on your board as well?

I don’t own any pedals other than ones I’ve built. Pretty sad really. There are loads of great production pedals out there, I just get a big kick out of having a board full of stuff I’ve designed and built myself – and I’ve got a unique sonic palette into the bargain.

What kind of music do you like to play?

I’ve got a large collection of instruments. I was a keyboard player before I learned (some) guitar. I like making random bleeps and drones on my modular synths as much as I like improvising on my baby grand. Or thrashing all hell out of my Telecaster. The last two songs I played/recorded were ‘No Quarter’ on my Rhodes, through a Causality 6 to get the trademark wobble, and ‘No One Knows’ on my 5 string bass, through a Thermionic Overdrive. Both were demos for customers.
The tube driven Thermionic Overdrive

Do you have a favorite dinosaur?

Of course! Who doesn’t have a favourite? Mine’s the K'Nex Construction Dinosaurs 20+ Model Building Set 71047.

If you could go back and change any way about how Frequency Central operated, would you change anything? If so, what and why?

Yeah, I’d just build one knob boosts and sell them for $300 a piece. Gosh no, I’m happy with how things are right now. Frequency Central is small enough to be a personal service, each build is special. I do a lot of custom stuff, rather than just off the shelf, that’s part of the fun for me, listening to what a guy wants and working out how to make it happen.  I don’t want to lose touch with that.  Mass production doesn’t really interest me. Handmade is where it’s at for me. 

Yes it's a boost, no it does not cost $300 

Any tips for those of us out there looking to get into building pedals or mini tube amps either as a business or for fun?

Building your own stuff is just great, search out the DIY pedal forums, there are loads of people doing it, and many people willing to give good advice to get you started. Do the research. Read everything you can find. As for business, be creative, strive for perfection, create a niche product, value your talent and your time.

Again, be sure to check out the Frequency Central's Site. If there's a certain pedal you've had an idea for but no one makes it, I think Rick might be able to help you out.


  1. Are the small amps loud enough to use when playing with a drummer?
    BTW love that font you use!!!!

  2. Haha, no! They're 1 and 2 watts at most. Really designed to get that cranked amp sound at low volume levels, and for home practice.

  3. Yup, they're just there to boost a regular amp, probably like an ac30 with a turboRAT. The tube-based stomp box is crazy though! They'd beat any old solid-state any time of the day - more so when plugged into a bigger boss of a cab head like a Messa Boogie or a Diezel. I wish I am this good when it comes to DIY electronics, man.