Eurorack Hardware (EH) Modules - DIY Builds
Spring is on its way and it is the perfect time for new modules to be hitting the market. We were stoked when the gang over at Synthrotek recently announced that they going to carry a new set of modules made by a relatively unknown company known as Eurorack Hardware (EH).
A total of 5 new modules in all, the OR, E-OR, ATT, AMIX and RING are going to make a splash on the modular scene. With that being said, we are excited about taking on the new DIY Kits from Eurorack Hardware (EH).
Who is EH? Who makes these new modules?
Eurorack Hardware (EH) has actually been around awhile, you just kinda know them in a different persona. Have you ever heard of Division 6? What about the Dual Mini Sequencer? Eurorack Hardware (EH) was founded by Scott Rise, who is also is the director of Division 6 Labs. Division 6 manufactured the infamous Dual Mini Sequencer and they produce other synth circuits and video game hardware mods.
EH are mainly known for manufacturing hardware for eurorack modular systems. They specialize in various rails, brackets and screws, and pretty much anything you would need to build a custom rack.
Upon partnering with gang over at Synthrotek the world was introduced to the OR, E-OR, ATT, AMIX and the RING. The five modules are described below, each with their own time lapse build, build notes and gallery.
Let’s get one with the builds…
Click on the link below to jump to the build:
OR – a passive dual OR Combiner module.
E-OR – described as a passive “selectable gate mixer.
ATT – you guessed, it a passive 2HP attenuator.
RING – a 4HP dual ring modulator for Eurorack
AMIX – a three channel active powered mixer in a 2HP module (ACTIVE SMD Build)
Eurorack Hardware (EH) Modules
OR - Passive Dual OR Combiner
The build of the EH OR module is relatively quick and easy. It is literally a few diodes and jacks. The panel is a black matte with white letting which gives the module a nice aesthetic. We used top down soldering with bottom touch up soldering on all of the points on this build.
One nice thing is that the red PCB soaks up solder easy and you have plenty of room to move your iron about as you tack everything down. As you can see from the build video below, one is done before you know it and you are ready to put the module to work.
E-OR - Passive Selectable Gate Mixer
Like its brethren kin, the E-OR is another quick build. The BOM consists of 4 diodes, 2 resistors , a couple of switches and a few jacks. The matte blank panel with white ink is consistent with the EH style as is the red PCB. We used top down soldering on a majority of the build and cleaned everything up by a quick reflow if needed.
Did you just bake a panel? Why yes, yes we did!
As you can see from the build gallery, we clear coated the EH panels and baked them on low for a short amount of time (20-30 min). This not only helps seal the panels, but it reduces the scratching of the panels during use.
We did this to all of the panels in the EH family and do this consistently with a lot of our builds depending on the style of the panel.
Links to fully assembled module, DIY Kit and BOM are found below:
ATT - Passive 2HP Attenuator
As with the other builds, we did bake the panel on the ATT to help resist scratching and wear and tear on the module. We know we are going to be using this one quite often. With its small size, being passive (requires no power) and its ability to handle 3 independent IN/Attenuate/OUT circuits, this module is a no brainer to pick up!
Links to fully assembled module, DIY Kit and BOM are found below:
RING - Passive 4HP Ring Modulator
The build of the RING module took a little more time than the other EH modules (aside from the AMIX). This was partially due to the transistors and being careful to keep them elevated above the PCB.
After mounting some of the jacks, you have to clip the soldering points to level them out with the PCB. We took the time to cover the area cut down with Kapton tape so that it would double protect the circuit. You can see the space needed in our gallery of the build below.
In the end, this was an easy build and we can’t wait to get this in our rack!
AMIX - 3 Channel Active Power Mixer in 2HP
As you can see from the build video and the gallery, take your time with the SMD components. Using solder paste, this helped keep the parts in place when we tacked everything down. Upon completing the SMD part of the kit, we moved on to the hole-through. Jacks were the first item to mount. Take note here that there is one set of jack pins that will need to be cut flush so that you can mount the power header.
Kapton tape was used again to cover the cut jack pin. This lines up with the power header to prevent cross touching of components. This isn’t required, but its just a protection measure we take from time to time.
Next, we move onto the power header. Here, you have to cut 4 pins from the underside of the header to ensure that it flushes up to the bottom of the PCB. After wrapping all of this up, move onto the potentiometers and standoff.
Like the RING build, take a little dab of solder to tack down the sides of the pots to the PCB. Pop on the black matte panel (we clear coated ours) and tighten everything down and you are good to go. You can now mix CV or audio signals and bring layers to your mix.
The Final Word.....
The EH line of modules are a modular utility dream apart from the RING filter (the RING isn’t a utility module). Being that most of the modules are passive and their footprints are relatively small, these modules just make sense. Everyone has a couple of HP to spare in their racks at some point. You can always use another attenuator or Either/OR circuit to help layers of music/CV intertwine.
The black matte with white lettering is also right on par with the recent influx of matte panels. We made sure to clear coat all of our panels to help with scratching. Though this isn’t required, it sure helps the longevity of the panel.
Building the modules was not a time consuming task. In fact we conquered all of the modules in about 3 hours total. This included panel baking, switching music and grabbing a ROCKSTAR to help us power through the builds. In the end, all of these modules are easy to build, with the exception of the AMIX if you are not confident in SMD soldering. Use of a digital microscope, Frog Tape and helping hands assisted in our builds and made things go a lot smoother.
In the end, we really enjoyed building the EH line of modules and look forward to what comes next for the company. With their low cost, low to no power consumption, these modules are a must have for any system.
If you are interested in picking the kits or the completed modules, jump to the links above and grab them from the gang at Synthrotek.
If you have questions about the build process or suggestions/feedback about this article, feel free to let us know by contacting us. We look forward to hearing from you!
Until the next build …