Korg Volca Keys Delay Circuit Noise

KorgVolcaKeys

I have had the Korg Volca Keys for a little over a week and have gotten quite comfortable with the unit. The feature set can be learned in a matter of minutes, but the sonic range of the instrument is impressive and much more broad than I expected. The strength of the Volca Keys is in the modes: poly, unison, octave, fifth, unison ring, and poly ring. The sound I posted earlier, for example, demonstrates the poly ring modulation mode. Lately I’ve been enjoying syncing the Volca Keys with my DSI Tempest and Korg Monotribe, but more about that later.

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Of course a hardware analog synth that exhibits the diminutive size and cost that the Volca Keys does is bound to have some limitations. From my perspective the most obvious limitation is the quality of the onboard delay. According to Korg’s block diagram the delay is the final circuit in the signal flow. Therefore, high frequency noise coming from the delay can’t be rolled off with the filter. The noise is most obvious when playing a sound that is programmed with the cutoff frequency most of the way down, the delay time at the slowest setting, and the feedback at the highest setting.

To illustrate the noise introduced by the delay circuit I created a few versions of a simple test sequence. One without delay, one with the internal delay, one with Ableton’s Simple Delay, and finally one with my Electro-harmonix Memory Man Delay. The sequence sounds pretty clean on its own, but buzzy, high frequency aliasing becomes audible when the Volca’s delay is introduced. In comparison, Ableton’s Simple Delay doesn’t add any noticeable noise, while the Memory Man adds a little noise (and pleasant chorusing), but nowhere near as much as the Volca delay.

Korg Volca Keys Sequence with No Delay:

Korg Volca Keys Sequence with the Internal Delay:

Korg Volca Keys Sequence with Simple Delay:

Korg Volca Keys Sequence with Memory Man Delay:

Some might find the buzzy delay noise desirable at times. To me it sounds more-or-less like a cheap, digital delay circuit that uses some down sampling and/or bit reduction to handle the memory requirements for the repetitions. I have also noticed that the filtering on the delay trails is significant. Cranking up the cutoff and lowering the attack, decay, and sustain on the EG produces obviously muffled delay trails. All of these limitations are not that noticeable when you’re using the Volca alongside two or more other instruments, but I plan on using my Memory Man as an alternative to the on board delay when it’s convenient to do so.

Post-prepared Piano Animated Sequence

I put together this animated sequence of the media from Post-prepared Piano to illustrate the relationships between the spectral analysis, the mapping with nails and twine, and the music from the piece. Thanks to Photosounder developer Michel Rouzic for suggesting that I make a video combining the sound and imagery after seeing the documentation I posted a few days ago.

Post-prepared Piano by John Keston and Piotr Szyhalski

Piotr Szyhalski and I have just finished installing a piece titled, Post-prepared Piano, in the Burnet Gallery at Le Méridien Chambers, Minneapolis. Our installation is part of a show called Interactions and features the work of select MCAD MFA students in collaboration with their mentors. Our piece consists of several components. The first part is a 14′ wide and 17″ tall inkjet print of spectral analysis from a short piano composition that I performed and recorded using my custom built, binaural head microphone (otherwise known as Vincent).

Below the print is an installation that Szyhalski constructed from tarpaper, nails, and one continuous piece of twine. This handmade mapping of the spectral analysis was then photographed and converted back into sound using Michel Rouzic’s excellent application, Photosounder. Thirdly, we installed an iPad with headphones that allows the visitors to hear the original recording, the nails and string version, and a combination of the two layered on top of one another (visit the tablet optimized webapp). The show opens today and runs through February 24, 2013 with an artist’s reception on January 31 from 6pm to 9pm. Read on for more details, photos and sounds. Continue reading

Casio Micro Microtrack

I created this microtrack from a tiny sample of a chord played on my Casio CZ-1000. I looped the chord and then ran it through a effect chain with five plugins, including Ableton Resonators, MDA DubDelay, Auto Pan, Chorus, and Reverb. I automated several parameters such as the delay feedback and tone.

Casio Micro Microtrack

Words to Dead Lips Closing Night Excerpt

As I’ve mentioned in some previous articles, I have been working on a multi-media dance collaboration, Words to Dead Lips, with Annichia Arts since last December that has finally come to a close. We staged three performances at Intermedia Arts in Minneapolis this weekend to a mostly full house. My part in the collaborative effort was to produce the music, and I was given an open mandate to do so. As is my preference, I opted to perform the work to the dance and projected imagery, rather than submit pre-recorded material. Although I adhered to an agreed framework for the soundscape, the improvisational nature of this approach made every performance unique.

The main tool that I used to generate the sound was my Max for Live patch, Grain Machine that explores granular synthesis via a multi-touch controller. I loaded it with five samples including Snow Melting into Lake Superior, One Hundred Sounds in Eight Seconds, High and Low Frequency Drone, and a couple of others for the piece.

Another component to the sonic environment was the noise shield. This device, that I built into saucer sleds, was used by the dancers to synthesize sounds using body contacts and a light dependent resistor. Here’s a five minute excerpt of audio from the closing night’s performance.

WTDL Closing Night Excerpt