Why choose a YellowRock amp?
YellowRock amplifiers are designed from scratch, not by cloning classic amplifiers. We've developed our own unique analogue circuitry and transformers to create distinctive rich tone that is YellowRock.  Our unique design coupled with quality components means that your YellowRock amplifier will have unique YellowRock tone that goes on giving.
Going Organic?
Digital amplifiers have come along way over the past 20 years and, for the listener, it's not so easy to discern an audio difference between recordings of digital and valve amps. For the experienced player the difference is often in the 'feel' of the amp and the touch-to-tone feedback valve amps produce, allowing the artist to express his or her feelings through music. APEM gives the artist natural analogue expression - Play it, Hear it, Feel it!

YellowRock amps are at home around the world running universally from 110 to 240 volts, 50/60 hertz, making them particularly versatile when touring. Contact us at info@yellowrockamps.com or visit the Events page for your nearest YellowRock showcase where you can experience the rich tone and versatility of a YellowRock amplifier.
So what is APEM.....is it a valve/tube amp or not?
APEM stands for Analogue Pentode EMulation; a method of emulating power pentodes (found in most valve amps) using analogue (rather than digital) solid-state devices. In other words we are replacing heat generating fragile power valves with our unique analogue design to generate the tones, sound volume and 'feel' you might expect from an all-valve amplifier whilst reducing heat and weight, and increasing reliability. No more power valve failures, no more valve matching and biasing. Simply, its the rich harmonic loaded tone of a tube pre-amp feeding the enhancing tone of an APEM power amplifier. As a point of reference, the warm vintage tone of a YellowRock CA35H amplifier has been described in 'Guitarist' Magazine (see 'Guitarist' review button above) as halfway between that of a VOX AC30 and a Fender Tweed Champ.
Our standard amplifier has an RMS power output of 30 watts which, using an APEM power amplifier, results in volume levels similar to 30 watts of all-valve power. In other words it's loud - usually more than enough for most indoor venues that wouldn't be miked. 

About the Engineer:
I have been interested in electronics since the age of around 10 when I was given a book 'How to build a transistor radio'. From then on I was hooked on electronics and now, too far past the half century mark, I'm still hooked. Of course the technology has changed substantially from the early 70s. However, at an early stage in my career I soon found that digital electonics didn't do it for me. So, as the song goes, i'm an analogue man in a digital world. Thankfully it's still an analogue world....really it is, and I believe there are a few of you out there who appreciate that fact - especially when it comes to the art of creating music.
For most of my career I've worked on power and analogue circuit design for space instrumentation where, of course, you can't afford to have failures in service! The knowledge gained in producing reliable circuit design, and my passion for producing great tone, goes into each unit commissioned.
I hope that you get an opportunity to play through a YellowRock amp and experience the unique tone and build quality for yourself. Let your creativity be amplified!

Yours sincerely
Robert Card