SM Pro Audio Nano Patch

[F5D]

I thought that I will start a new thread for this product instead of adding everything to the same thread. So let's continue discussion here instead...

So, the nano patch arrived 2 days ago.



It uses a different potentiometer than mpatch 2 but they are labeled the same so the one which the nano patch uses is maybe a new model of the "same" potentiometer. At least sm pro audio website claims that the nano patch has the same potentiometer as mpatch2. The build quality is ok again as with mpatch2, not pro quality but very good to expect from a 50 euro/dollar volume knob. The nano looks cool on the desk and it has rubber feet under the enclosure which keep the nano steady. The knob is very light to turn so it doesn't feel as pro as it might but it still is good. The mute switch works without any clicks or pops in the sound and feels solid as well as the knob itself. This thing won't break down easily. The connectors are ok quality. Nothing special but they work. So, it looks cool and has a perfect size at least for my use. I really like it.

Then the sound... It's a passive attenuator, so it doesn't color the sound even near as much as all active volume controls (which need a psu in order to operate). Anyway, I noticed more balancing problem with the nano patch than with mpatch 2 earlier. Every individual potentiometer is different so that is the problem. As with mpatch2, the knob is very sensitive and you don't have to turn it much to make things loud and because of the balancing problem I decided to build an extra attenuator inside the nano patch.

I used 5kohm resistors in series with the potentiometer's inputs and 1kohm resistors in parallel to the ground from the inputs. These resistor values give about 14dB extra attenuation and the input and output impedances still remain at good levels. What this basically does is that when I begin to turn the knob from -infinity (mute), the signal is 14dB quieter than before and I can easily pass the point where the balancing problem is audible before I can hear the sound. If I am listening to music on the background, I can now turn the knob to -50dB position. Earlier it was much closer to the -infinity point and the balancing problem was audible. I can still turn the volume louder than I ever want but the potentiometer can now work at more linear area and the balancing problem is totally inaudible at every level. Nice!

The nano patch is a good volume controller even without this mod which I built but it's even better with the mod. However, I use the nano patch only in unbalanced mode and built the mod only for unbalanced operation. I should mod also the inverted inputs the same way if I want to use balanced operation.

When using passive attenuation, you can feed the attenuator with 100% signal from your audio interface's d/a-converter and get full 24 bit dynamics. The sound is clearer, bass goes lower, kicks more, harshness at high frequencies is gone, stereo image and everything is just better after using digital volume control from the audio interface. I used about -56dB levels with my motu 828 mk2 which ruins the output digitally because the d/a-converter is working only at about half resolution. Now I have turned it up to -0dB 100% and the nano patch handles the volume control. Full 24bits sounds good!

[jasedee]

Looks like a cool little toy! Will definately add one to my setup soon