Shruthi Knob Specs

Does anyone happen to know the shaft size (height) and diameter specs for the standard Shruthi knobs? Are these given in metric or standard units? Using a ruler, I measured the shaft height to be around 1cm and the diameter to be ~5 mm. But I just want to confirm that these are the right dimensions before ordering different knobs.

I am actually ordering the knobs for my Prophet '08 rack. The stock knobs on the Prophet are these awful hard plastic things. The standard Shruthi knobs will work on the Prophet and feel a lot better. However, the indicator line on the top of the knob needs to go in the opposite direction. (On the Shruthi, the line goes in the direction of the curved part of the “D” shaft. It’s opposite on the Prophet.) Does anyone know if you can specify which direction the line should go when ordering knobs?

Any help you can provide is greatly appreciated.


P.S. I was looking at different knobs on Mouser. But I couldn’t find what I was looking for. Is there a better resource here in the US for knobs?

You can have a look at the official BOM here:

Depends on the knob, check the data sheet to see if the knob comes with the pointer going in different directions. There are knobs at mouser that have it both ways for sure though

Thanks for the replies elektrosamplist and altitude. I went to the BOM page listed above but I don’t see any specs for the knobs, Under Step 10 of the assembly instructions it just says “Add the controls – the 4 potentiometers, the encoder and the 6 switches.” Am I missing something?

P.S. I’ve programmed about 25 patches on my Shruthi so far. They sound pretty darn good if I do say so myself and really show off what the synth is capable of. (I used to work for one of the leading soundware developers back in the day so I’m actually pretty good at this.) I would be happy to send you the patches in return for your assistance helping me select the right knobs. :slight_smile:

Isn’t there a Mouser link from the spreadsheet listing the components?

You want to look for 6mm D-shaft knobs at any rate. The only thing to worry about is the pointer orientation. Each different manufacturer uses a different way of telling. If you look at Sifam knobs for instance you’ll see that the flat part is 4.5mm. More on orientation is listed in the data sheet.

As luck would have it, the Eagle plastics knobs at Mouser will work just fine. The Eagle BA600 series is recommended for the encoder. The other pots use 450-BAx61 where x is 1,2,3,4 or 7 depending of what indicator line color you want to match the case.

I don’t think they have them at Mouser but RS components has these Sifam Knobs wich are cheap and also have the nice rubbery feel and have the indicator reversed.

Oh and you can put the patches here

Hi Jojjelito and shiftr,

Thanks for the info/help. I really appreciate it. The Sifam knobs are exactly what I was looking for - I like the ones without the “skirt” on the bottom.

The RS Components site appears to be in the Netherlands (the site is in Dutch). However, I clicked around and found a sister (?) site in North America called Allied Electronics. They carry some Sifam knobs but not the ones I am looking for. I believe the Sifam part number for the 6mm D-shaft knobs with a 4.5mm flat size is 3/03/DR110 006/26. These are the black knobs with a white indicator line without the skirt. (BLK1004/WHT224).

I will keep searching to see if I can find a distributor in the US. If you know of one, please let me know.


Just out of curiosity, where does a company like Clavia source the knobs for their keyboards? Do companies like Clavia typically buy knobs in bulk from a supplier or make their own custom knobs? Just wondering.

the rs components link was dutch because i send it to you… i get to see the dutch shop because i’m in holland.
But it’s quite big distributer with branches across the globe

Could be that clavia had made them especially for them… but could also be some knob from some factory… A lot of this kind of parts are only available directly from factories or resellers who only sell large quantity. Same goes for the really nice knobs the MI modules use…

The MI knobs are custom made (choice of color) from Rogan in the US. Sifam knobs are carried by Selco Products in the US, they have worldwide distribution.

Otherwise, I suggest looking at the current MIDIbox bulk order for encoder knobs from Albs Alltronic in Germany. They have the knobs used on the Waldorf Q synths etc.

Thanks Jojjelito. I found the knobs I was looking for on Selco! I will upload a photo of my Prophet '08 rack with the new knobs once I receive them. I might even replace the stock knobs on my Shruthi with these Sifam knobs. :slight_smile: