Erica Synths Perkons HD-01

Perkons is the Latvian name for the Baltic god of thunder, a fitting name for a thunderous drum machine.

Erica Synths are rapidly becoming one of the most prolific instrument manufacturers around. Just a year ago, I reviewed their excellent LXR‑02 drum machine, and even then, they had already announced the Perkons HD‑01, a chunky‑looking drum and drone synth. Production has been slow thanks to global chip shortages, but now the Perkons is finally available en masse.

There are four drum voices, each with a choice of three synthesis algorithms. The oscillators are digital, whilst the multi‑mode filters and overdrive circuits are analogue. The sequencer consists of four rows of 16 triggers, one for each voice, and many fun functions like probability, playback direction, modulation recording and trigger conditions. There is a global BBD‑style digital delay, with separate send per voice and a single LFO that can modulate most voice parameters.

From a glance, it’s easy to tell that the Perkons is designed for hands‑on control. It follows the same desktop build format as the Syntrx, their EMS VCS 3‑inspired semi‑modular synth. It’s a desktop unit, around 46 x 32 x 9cm. The wooden sides, aluminium powder‑blue case and substantial knobs give it an air of class, and the sequencer section is populated with satisfyingly chunky buttons. It’s an imposing‑looking instrument, but do the sounds match the look?

Synthesis

Each digital engine has three algorithms to choose from, and each algorithm has three modes. Broadly speaking, voices 1 and 2 are more tonal — good for kicks, toms and synth sounds. Voice 3 covers snares and percussion, and voice 4 focuses on noise, hats and cymbals.

With each voice having three algorithms and three modes, there are 36 variations of synthesis algorithm to choose from. In reality, some modes only change minor details like a transient volume. In others, they are more like different algorithms, drastically changing the sound.

The panel layout for each voice is identical. Each voice, algorithm and mode offers the same pitch control, decay, filter cutoff, overdrive, effects send, overall level and two ‘param’ controls specific to the currently selected algorithm mode. This generic layout makes things simple. A knob will generally do the same thing no matter where you are. But the lack of algorithm‑specific labelling means you are flying in the dark about what the ‘param’ controls are supposed to do. The algorithms and modes have numbers rather than useful names. Instead of memorising the algorithm and mode numbers or keeping the manual nearby, my preferred approach was to blindly switch modes until I found something I liked. Some extra information on the panel might have helped.

Voice 1 will likely be your kick‑drum sound, although the algorithms allow you to stray far from that brief. You can choose between wave folding, wavetable and FM algorithms, with the three modes performing tasks such as transient shaping, wavetable selection, or in the case of the third algorithm, a more drastic tonal shift caused by changing the FM waveforms.

Voice 2 contains three flexible ‘drum’ engines. Like voice 1, they use wave folding, wavetable and FM synthesis, but the algorithms are tuned differently. This voice is more suited to percussion, synth, toms and effects.

Voice 3 will focus on snare, clap and tom‑type sounds using noise, ratcheting, FM and Karplus‑Strong synthesis. It introduces noise and would also suit more experimental sounds.

Voice 4 concentrates on hi‑hat, metallic and noise‑based sounds utilising different noise types and some specific closed, open and ride synthesis models.

Overall, the synthesis feels simple, bold and flexible. Despite its digital sources, the Perkons sounds massively analogue. The result is a sharp sound with plenty of body and enough low‑end to knock a house down. That is assuming the neighbours don’t call the noise pollution police first!

The excellent analogue multi‑mode filters offer low‑, band‑ and high‑pass modes. No resonance control exists, but you will find a very usable analogue overdrive circuit. With no resonance, the filters are used more like an EQ to shape the oscillator sound. The only possible modulation is via the global LFO or by automating using the sequencer. It’s a shame there isn’t a way to use the amplitude envelope to vary the frequency, but that would have needed another control on the front panel.

One neat little bonus is the ability to turn the Perkons into a drone synth by increasing a voice’s decay parameter to 100 percent. The VCA will stay permanently open, and the oscillator will drone indefinitely. Suddenly the Perkons is a very different synth, but the ability to automate the decay parameter means you can drop in and out of ‘drone mode’ with some simple automation.

A pattern is limited to a maximum of 16 steps per voice, but you can chain multiple patterns in any order to create longer sequences.

Sequencer

Nowadays, a good drum machine can stand or fall by its sequencer, and the Perkons delivers plenty to get excited about. A pattern is limited to a maximum of 16 steps per voice, but you can chain multiple patterns in any order to create longer sequences.

The grid of 4x16 trigger buttons enables or disable steps in the sequence. There is also an optional Accent mode that allows two volume options per step. If programming patterns isn’t for you, you can record live using the four trigger buttons, MIDI input or the analogue trigger inputs.

The Perkons measures 315 x 454 x 90mm (including the knobs) and weighs in at a hefty 3.7kg.

Tracks can play back in different directions — forward, reverse, ping‑pong and random — with individual clock division, multiplication and loop points. Every step can also benefit from ratcheting up to five triggers within a single step. Per‑step ‘odds’ also dictate how often a trigger will play. For example, set it to 1/4, and it will play every fourth pass through the sequence. Set it to 7/8, and it will play seven times out of eight. Finally, probability can be set to 10, 25, 50 or 90 percent, randomising the chance of a step triggering. These functions allow for much more complicated and evolving patterns than the initial 16 steps might allow.

The most potent trick up the sequencer’s sleeve is the ability to store parameter changes per step. Any combination of knob and switch automation can be stored, allowing for dramatic or subtle sound changes per step. Holding a step button and moving a control on the associated voice will commit that change to the step. You can even hold a modifier to store that parameter for all four voices at once, allowing for kit‑wide automation. Alternatively, you can put the sequencer into record mode and, as it plays, move knobs and switches. The resulting parameter changes will be recorded in the sequencer. It is a step sequencer, so the recorded automation is quantised to the steps of the sequencer, but you can enable a glide function, which can smooth out the automation between steps. All these features can be used in tandem while the sequencer is running, making the Perkons a live performer’s dream.

There are some additional tools to help in your programming adventures. For example, you can easily copy and paste individual steps or delete automation for the whole pattern or individual steps when things get too crazy.

Patterns can be saved, as can kits. By default, kits and patterns are saved and loaded separately, which means if you have a killer drum groove, you can try out other kits. But if preferred, you can enable ‘kit linking’, which will load the corresponding kit when loading a pattern.

The Perkons can save up to 64 patterns and kits in a bank, and the SD card can store up to 64 banks. That’s a whopping total of 4096 kits and patterns. There is a slight pause when switching between banks while they load from the SD card, so if you need instant kit or pattern switching for a live performance, you must stay within a bank. I suspect 64 patterns will be plenty for a live performance though, so no problem there. Speaking of performances, anyone playing live will appreciate the many ways to sync the Perkons to other machines. The usual MIDI Clock options and analogue sync with adjustable ppqn are available. You can also tap tempo for manual sync, and tempo nudge for keeping time with other musicians or DJs.

The final sequencer features worth looking at are groove and shuffle. Groove allows you to choose one of four groove templates for each voice. These grooves apply a volume map, varying the volume on specific steps. There are three preset grooves and a random one. Shuffle uses a standard 16th swing. Applying shuffle and groove per voice makes for combinations that can subtly or drastically change the feel of a pattern.

L... F... O...

The Perkons’ LFO is another fun source of modulation. It can be assigned to any of the eight knobs for each voice: tune, decay, param 1, param 2, filter frequency, drive, effects send and level. There are seven waveforms and a simple master speed and master level control. Although it’s bare‑bones, it helps create some non‑sequencer‑specific movement in a kit and can be used subtly or drastically as you see fit. The only thing I miss, something that the Erica Synths LXR‑02 has, is an LFO reset feature. Being able to reset the LFO using a sequencer voice trigger was something I used a lot, and I miss it here. LFO setting are saved with the kit.

Master Section

As well as the overall volume control, the master section contains the controls for the BBD‑style delay and the master compressor. The compressor is only audible when monitoring the main output, but the thoughtful inclusion of send and return jacks for each voice means that you can process each voice individually (bust those guitar pedals out!) and then loop the effected voices back into the machine to be processed by the delay and compressor. You can take this one stage further by using the master send and return jacks to replace the delay with some other effects and return the mixed signal for final compression.

The included delay is excellent. It has an analogue character, despite being completely digital. Alongside its time and feedback controls is a switch to alter the time range from short to long. With short times and the use of a second dedicated LFO, it’s possible to do a variety of modulation effects and feedback tricks. The LFO is a simple sine wave with rate and depth, affecting only the delay time. You can conjure chorus, flanger‑type effects and some wilder wobbles with it. Longer delay times allow for more traditional dub‑style delays. Apart from another switch that changes the colour of the delay tail (dark or bright) and a hidden preference that purports to give a more vintage character (although I couldn’t hear much difference), there’s not much else to it. Nonetheless, it is a very useable effect and sounds so good you’ll likely overuse it.

MIDI Control

We’ve already mentioned MIDI and analogue clock sync, but there is also an excellent MIDI implementation for those wanting to sequence the Perkons from a DAW or external sequencer.

Each voice can be triggered by analogue triggers, by different notes on the same MIDI channel, or by the same note on different MIDI channels. Sadly, you can’t play voices chromatically, which would be a nice improvement in a future firmware update. One advantage of sequencing with MIDI is velocity sensitivity. You get full volume range via velocity instead of the on, off or accented choices when using the internal sequencer (although you can use per‑step automation for level as a workaround).

Each voice parameter also has its own MIDI CC assignment, which can be sent and received. There doesn’t seem to be any way to control the master delay, compressor or LFO, however, which seems a shame. If the default CC assignments don’t suit you, you can edit a text file on the SD card to change them.

Perkons is the Muhammad Ali of drum machines. It punches hard and with effortless grace.

Conclusion

On paper, a four‑voice drum machine doesn’t seem all that appealing, especially at this price. But I guarantee that perception will change as soon as you hear it. Perkons lives up to its namesake, the Baltic god of thunder, with a colossal sound that doesn’t fail to impress. Kicks range from tuned sub‑bass heavyweights to spectrum‑filling distorted gabber giants. Percussion is snappy and sharp, covering everything from analogue toms, ratchet claps, laser zaps, claves, blocks and Karplus‑Strong plucks. Hi‑hats and cymbals sizzle brightly, and although there are occasionally some piercing frequencies, you can almost always eliminate them with careful tweaking. Overall, the Perkons excels at big, brash sounds. It is capable of subtlety, but it can be harder to achieve. If you want 808 or CR‑78 style finesse and soft edges, this maybe isn’t the right drum machine. The Perkons is the Muhammad Ali of drum machines. It punches hard and with effortless grace.

The design is hands‑on, and once the muscle memory kicks in, your fingers will be dancing around the front panel like Jeff Mills on a 909. The performance workflow of saving patterns, then slowly morphing them to something new before returning to base with a reload, is possible here. And with 64 instantly recallable patterns and kits, there is enough to keep the party going without ever stopping the transport.

The Perkons also encourages creativity. I love the audio send and returns. I spent a most enjoyable evening with the Perkons on the rug, a bunch of cables, and some effect pedals, experimenting with different chains on individual voices and the master channel.

There are some limitations, of course. If you’re a fan of stereo drums, this may not be the drum machine for you. Alternatively, you might accept the trade‑off and process a couple of voices externally with stereo effects. Also, it’s unlikely to be your one‑and‑only drum machine. With only four voices, it does need some backup occasionally. However, those four voices are quite capable of filling the frequency spectrum. Less is more in this case.

Erica Synths are on a roll. They consistently bring out unique instruments that are fun to play. The Perkons HD‑01 is no different. It has sonic character by the truckload. I think the Latvian god of thunder would approve.