Skip to main content

Quick Tip: Differences in Eurorack Modules

When you have multiple modules of the same brand and type , you might sometimes experience small differences between those Eurorack modules.
Sometimes oscillators are tuned differently and you can't get them to match.
One may sound lower than the other with each's controls identical, yet they sound different..
This is often not something to worry about.

Four A-110 VCOs that look the same,
all sounding (slightly) different.
Although most modules are thoroughly tested, some batches may indeed sound a little different due to (internal) trim-pot settings, differences due to tolerances of the electronic parts, etc...

If you want to compare your modules, it is always smart to check the production date/ batch number on the test label and/or on the PCB (version nr) first.
Usually this can be found at the inner side of the front panel.

If the numbers match, and one of your modules does sound different than the other one, you might check out the trimming pots on the backside of the module on the PCB.
In most cases this can be easily fixed with a small screwdriver once you located the right potentiometer (often printed on the PCB or can be found in a manual).

Sometimes it just has to do with other components.
During the production-years of a module the values of all kinds of parts of your module may have been changed a bit (for example R77, R86, R88).
These differences can sometimes be audible, sometimes only to the trained ear...

Especially the specifications of a main circuit like the 74HC4046 (Used in the Phase Locked Loop - A-196 PLL module) may differ for different manufacturers (even different batches from the same manufacturer) of this circuit.
Because the PLL module is not a precision module like a VCO there are no trimming potentiometers available to balance such tolerances.
You'll just have to live with that...

Popular posts from this blog

DIY Modular Case Ideas

There are many ways to house your (eurorack) modular synth, i wrote about the pre-manufactured options from Doepfer earlier, find that post HERE, but of course you can also try to build you own case.
There are many ways to make your own A-100/Eurorack case if you start out with just the basic rails and busboard, and you can make it as cheap or expensive as you can.

Check out a few ideas;
Wooden cabinets and side-panels are still very popular amongst (modular) synth enthusiasts.
These simple case standards for the pre-manufactured LC9 cases are very simple, and can be sooo useful Also check out the other great modular pictures on his site.
Matthew Goike (@Goiks) also has some nice wooden cabinets on display and for sale on his website:

...or do what Stretta did (or rather what his brother did), make a high-end wood/brushed aluminium cabinet with integrated LED-lights and some …

Doepfer A-150-8 Octal Manual/Voltage Controlled Programmable Switches Announced

Doepfer has just released some info on their new modules for NAMM 2017 (19-21 jan.) Besides some vintage editions of existing modules, the A-135ABC VC Performance mixer modules, the A-110-6Trapezoid Thru Zero Quadrature VCO and a new A-100LC1 case (economically priced small housing with 48 HP width) there was also one other interesting new module announcement:
Module A-150-8 contains eight manually/voltage controlled switches.  Each of the eight switches has a manual control button (Man.), a control voltage input (CV), a common Out / Input (O/I), and two In / Outputs (I/O1, I/O2).  The switches are bi-directional, i.e. they can work in both directions, so can connect one input to either of two outputs, or either of two inputs to one output. 
Two LEDs show which in / output is active (ie. which is connected to the common out / input).  In addition the LEDs are used for the programming of the module: For each unit the operating mode can be selected:  Toggle or Level controlled. In Toggl…

Happy New Year From PatchPierre

Hi there, it's me again... Happy New Year!

You might have noticed that I havent posted a lot in the last 2 years...
It's been a rough time for me since the sudden loss of two parents within a relatively short time-span and I really needed some time to get myself together... to set things straight, finding myself and selecting priorities... even my regular work suffered from this breakdown.

It took a while to understand it all, and to get a better grip on it, and it's sometimes still not very clear.
I think I have found a way to cope with most of it now... although the slight autism that I have (ADD-like) doesn't make it easy for, especially in crowds with lots of people I don't know...
On my journey I also (re-)discovered the beautiful woman that has always lived inside of me and that i need to accept and cherish... more on that maybe later... I'm not considering changing the name of the blog to PatchPetra.Net 😇 (...yet), but you might spot me somewhere at mod…