Rega P10 arm screws for cart

I see that my Lyra Kleos is fixed to the arm by 2 screws. But I see another hole . Should a third screw be fixed?

@Suedkiez , Nlot, Richard Dane ? Thanks to clarify

The third screw hole is there only for compatible cartridges, e.g. Rega’s own.


Apheta 3 on my P8 for instance.

1 Like

But isn’t there a third hole in in his picture, meaning it’s a compatible cart?
Only looks to be a small diameter, not sure if that’s the same as “compatible” ones.

1 Like

It looks rather small. Probably one for Lyra to confirm or otherwise.

…? coincidence that the Lyra and Rega holes seem to be aligned.

Is it me or is that smallest hole the last of fours holes gradually getting smaller and I see it as just a design feature ? If it was a hole for a screw would it not be countersunk in some way to match the 2 slots being used ?

No, not for Rega cartridges, which have 3 screws. The three point fixing on Rega arms means that overhang is automatically correct for Rega cartridges, and adds some tighter coupling too.

It would be a bit odd if the same applied to the Kleos, because Lyra are obviously not intending to build a cartridge that is fully compatible to Rega arms, or else they would most likely set the VTA for Rega arms without a spacer (and I would have given @frenchrooster an easier time :wink:)

But who knows, maybe that’s the overhang they recommend for Rega arms and they figured why not add a third screw hole. Best to ask them.

(Side note: the 4 holes in general are not just a visual design thing but are there to minimize arm weight without harming stability)

The mystery remains. I will try to ask Lyra. Maybe a little screw can be added?
Thanks for now for all your replies


…maybe Lyra are planning an accessory!

Like what?

A special screw


Maybe it’s to fix the underneath part?

…that’s more mysterious. It must have some purpose…

1 Like

I send a message to Lyra France and Michael Fremer.

I found this written on the vinylengine forum but cannot vouch for this user knowing what they are talking about:

“The Delos is a good match for Rega arms, there’s a small guide hole on the top of the cart that matches up with where the Rega’s 3rd mounting screw normally goes. So assuming the cantilever is straight it’s pretty easy to dial in the overhang”

In particular not clear whether this guy means if it’s on purpose or just happens to match up

Using Rega’s three bolt cartridge alignment means you also accept using their chosen alignment geometry, which is Stephenson, IIRC. Not every one wants to use that. I use a Clearaudio IEC alignment geometry, which is closer to Lofgren A (Baerwald).

Yes but this thread is about the Lyra cartridges and not Rega’s. The Rega cartridges were only mentioned because they come with the third screw by default, feel free not to use it. The question here is what the purpose of the little hole is on the Lyra, which is clearly not a mounting screw hole

So it’s to make a right alignment?

Looks like that’s a good explanation.
I prefer that it is for inserting uranium rods (oops, I hope that the CIA’s AI does not pick up on that one).