Nord User Forum

[Chaostar]

Hello to all!

I recently bought a Nord Rack 2 synth and i get the folowing problems :
Some patches dont make any sound at all or have a glitchy noizy thing
Some other patches as i just play with my keybord seem to be losing gain
or morphing constantly and changing.

My keybord is a Doepfer LMK2+ (works fine with every other rack unit i have)
and the midi interface is Motu micro lite 5x5
Im using Cakewalk Sonar X1 in my Pc

Is there a way to check if the unit is ok? A ROM check when startup or initialize or something??
I tried to store other presets with nordgen and in some cases it works in others it doesnt
overight and the glitchy sound remains.

[mjbrands]

Have you checked what comes out of the Rack 2 via MIDI when it seems to be acting up? One of the things it could be is a knob that doesn't work properly anymore. If that is the case, for most knobs the Rack 2 should start sending MIDI data, because it thinks the knob is being turned.

[Chaostar]

No i havent checked that! thanx! i will push record in my daw and filter the event manager to see the midi data that is being received! that could explain the sound that alters without me touching any knobs but the glitchy noises in some presets?

[mjbrands]

It might very well be something else, but at least this is something you can try fairly easily.

Something else you could try: switch to 'Local Off' mode (see page 58 and 61 of the manual).

When you turn a knob, the front panel (and keyboard, if you have the keyboard version) sends MIDI data to the sound engine and that makes sound. Reality is a bit more complex, but that's pretty much how it works. You can turn this off however and that's done by turning 'Local' (other Nords usually call this 'Local Control') on or off.

Send it some MIDI via the MIDI port (maybe via your sequencer), ideally a single note that is kept pressed down. If the sound acts up, try turning 'Local' on and off. If the sound changes (behaves with Local off), it is almost certainly something with the front panel. Conversely, if it has no effect, you might've just found out it is not an issue with a port or something like that.

[Chaostar]

well this is what i get when i record midi from the nord rack either Local On or Off
4 controllers are always transmitting without me touching any knobs

cc 27, 33, 37, 40

if i am correctly these are Modulation envelope decay, Osc 2 Fine Tune, Amp envelope sustain and Filter envelope sustain


you cant work like that...any way this could be fix?

[Mr_-G-]

Hm... I do not have a rack, so I can't test, but is the column to the right after "Control" the MIDI CC number? and the next one the value?
If you look at the data, it seems that the values between the consecutive CC bytes (let's say all the CC 33) are just very close to each other (55, 56, 55, etc).
I wonder if the pots are slightly worn/dirty and the encoder senses a tiny difference in the dial position/resistance (are they carbon pots or digital encoders?) over time (like if they are not making a constantly stable contact).
Have you tried moving them one way and then back, to see if they still send that data out?
If you look at the image, these fluctuations are not synchronous so I guess that it is the pots (differences detected at different times) rather than a board malfunctioning?.

[Chaostar]

yes next to control is the cc number and next the value..you can see it also in the first pic that the values are closely
i tried moving all the knobs in other positions but stil it sends these values...even if i record a knob motion all the way from left to right
it still transmits my movement and the static one

the nord rack 2 has knobs not digital encoders and i think they are not supose to transmit anything unless you do ti, right?

whats the meaning if its keep sending e.g. the Filter envelope sustain constatly??

[mjbrands]

4 controllers are always transmitting without me touching any knobs

cc 27, 33, 37, 40

if i am correctly these are Modulation envelope decay, Osc 2 Fine Tune, Amp envelope sustain and Filter envelope sustain

Yup, you are correct.

you cant work like that...any way this could be fix?

Something you could try: turn the knobs all the way from one side to the other side and do this 5-10 times. Might help a bit.

Cleaning them is one option; that might make it go away, for a while. A structural solution would be to have those pots replaced, but you might as well start with cleaning them since you can always decided to have them replaced. It would probably be a good idea to contact Clavia and ask if they have any recommendation (they have a contact form in the Support section of their website).

Cleaning them would require opening up the unit and partially taking it apart. That's no problem if you trust yourself with something like that, but I certainly do not suggest doing this if you have doubts about your own abilities/experience with something like this. You could also have it repaired via a service technician - I'm sure the importer for Greece has contact information for companies that could do that for you. You can find a list of distributors by clicking on Distributors (top-right) of the Nord site.

You might know someone who repairs electronics - he might also be able to help you. If you do decide to clean the pots yourself, be aware that there is a chance that the cleaning product you use could contain solvents that damage the pot further (in time). Generally you'd use a special cleaning agent you spray in the pot; spray (or drip) some inside the pot, turn it a few times and let the residue (if any) drip out of the pot. Now let it dry for a while. The better ones usually also contain a lubricant to keep the pot turning smoothly. I've read good things about DeoxIT FaderLube, but that stuff may be hard to find outside the US. In general there's a lot of debate about the best stuff to use and if some (all?) cause damage. I generally just stick to what manufacturers of equipment (like Fender, etc.) suggest.

[Mr_-G-]

Just imagine that the pot is set to a position where the resistance generated is a value that is between the thresholds to send bytes 44 and 45. Unless there is some low pass filtering of the pot value (and that would bring a different type of problem) you might get an intermittent switching between those 2 values. I guess that this would be worse if the encoding is fine-grained (e.g. the values encoded are 12 or 16 bit rather than 8 bit) because the thresholds get relatively closer (in magnitude) to the fixed noise in the system. So you would see more alternating bytes being sent out even if not moving the pots
The effect of this might not be noticeable depending on what the values do. Let's say the filter opening state controlled by the EG sustain varies a tiny bit. I bet you won't notice anything at all. This would happen in analog synths anyway; but in this case a continuous scale of voltages is converted to a discrete numbers.
I think you would expect this behaviour at certain position of the pots, but IANASM (I am not a synthesizer manufacturer).

[WoutBlommers]

The improper setting is the result of a bad pot.
Get the synth to a repair tech and replace the pots.
It will be gone.

BTW if the parameter jumps over a great value (e.g. from 0 to 100, which is audiable), this is the Sysex value and the physical knob on the Panel are different that way. Surely a bad pot.

Wout