SL2 tweeter set up and speaker cable suggestions

I know there’s plenty of tips on the forum on setting up SL2 speakers. I’ve been experimenting with the best speaker placement in my modest sized listening room but I’ve run into some problems.

I’ve been running TQ Ultra Black II cables with my old ATCs and I love the sound of the cable. I’m realising now though that they may not be a great match with the SL2s. The top end is clear and to an extent I can hear a lot more detail than I could with my ATCs. However, I’m struggling to listen to music over extended periods. The treble while clear, is at times jarring and now my tinnitus has really kicked in! I’ve tried positioning the SL2s with and without toe in so the tweeter is not directly firing at me but nothing makes any difference.

Any suggestions on which speaker cable works best with SL2s? (I’m assuming NACA5, Superlumina or Witch Hat Phantom?).

I’d welcome too suggestions on how best to get the tweeter centrally aligned in the front plate. I’ve tried loosening and realigning the three screws at the back of the top plate that hold the tweeter unit - can these be used to align it or is it best only to adjust the four screws on the front panel?

I would use NACA5 - indeed that’s just what I do use with my own SL2s.

Don’t mess around with the 3 bolts holding the tweeter on the arm - these are really for helping alignment at the factory and shouldn’t be messed with unless absolutely necessary. Loosen the front shroud and vaguely centralise it. And make sure each side of the tweeter arm is fully seated in the base. Any deviation here puts the arm askew and then alignment is really difficult. Then, when you think everything is OK, align the front shroud so there’s a nice even gap around the tweter and tighten it up.


Ok, thanks Richard.

I’ll see if I can arrange a loaner NACA5 cable from my dealer at the weekend. I’m hoping that will take off the hard edge I’m hearing with my TQ cable.

I’ll need to reset the 3 bolts holding the tweeter as they were as I’ve already adjusted these slightly. I’ll then adjust the front shroud and make sure each tweeter arm is fully seated as you suggest :+1:t3:

I initially used TQB and very quickly swapped to NacA5, and later to SL. Have the speakers pointing straight forward or with the merest hint of toe in - mine are 3mm nearer the wall on the inside edge. I sit 1.8 times the distance from tweeter to tweeter away.

As Richard says, get the tweeter arms seated and absolutely vertical. The front plate is likely stuck tight. Lay the top box on the floor on its back, remove all four bolts from the plate and pull it off. Replace the box, centralise the plate and tighten it up.


And make sure the tweeter has a sort of springy bounce when you tap it…

Also experiment with having the speakers slightly further apart than you might imagine feasible.

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The tweeter doesn’t have a springy bounce as it’s rigidly attached to the stand. The speaker cabinet should move if you tap the front with your knuckles, while the tweeter remains stationary.

I think you misunderstand me, Nigel. I’m sure we set SL2s up the same way.

Let me put it in more detail which will moreover be more helpful for the original poster.

The tweeter is mounted rigidly on its plate and to the arm but the bolts at the bottom of the arm should not be tightened up so tight that when you tap the tweeter mounting plate it and the arm do not move. The assembly should give slightly and bounce back. This is the SL2’s equivalent of the slotted decoupling plates on the IBL, SBL and DBL.

However, I’m not at all sure what you mean by:

The top speaker cabinet on my SL2s didn’t move unless you gave it an almighty great shove :slight_smile: The front baffle plate is bolted to it and it rests pretty solidly on its pips.

In my experience the cabinet should not move, but the tweeter mounting assembly should have some springy/bounce on the arm rather than be completely rigid. I hope that’s clearer.


Yes I’m pretty sure that if you prod the tweeter it will move back and forth.

Similarly if you prod the lower cabinet it will move independently of the tweeter arm on its leaf spring which remains still.

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Exactly! What’s important is that the tweeter returns to its original position rather than simply moving if you push hard enough and then staying where it’s moved to. A position flush with and centred within the plate is essential.

I’ve found that unless you tighten the tweeter arm’s bottom bolts as much as humanly possible, the arm flops against the back wall or the cabinet. So it’s effectively stationary at all times. It’s the cabinet that rocks on the leaf spring while the tweeter remains stationary. The key thing is to get the cabinet absolutely level and planted four square on the floor. @Richard.Dane has provided excellent instructions on here.

Bang on. But in having to tighten up the arm bolts so much, it can move the arm out of the bottom bracket slightly, so ideally you want to be pushing down on the arm hard (but ensuring it remains perfectly upright) while you tighten.

Quite so. Doing this with the top box out of the way means it’s easier to push down while tightening. I really don’t understand this idea of the tweeter arm bouncing. Mine certainly don’t.

Certainly the arm itself shouldn’t bounce.

I don’t think they mean bouncing just oscillating back and forth when gently tapped. That’s what mine do but both cabinets are rock solid.

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Exactly. If you gently prod the foam bit of the tweeter it moves gently back and forth until residing in its original position flush with the shroud.

If that’s the case they are set up wrong. The cabinets should oscillate. The tweeters should not. If you tap the cabinets they should move while the tweeter stays put. Maybe you just think it’s the tweeters moving when it’s actually the cabinet.

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Well, let’s not exaggerate about the arm bouncing - I’m talking about the tweeter being able to cede position when pushed and spring back into the same (correct) position with a bit of oscillation (right word RackKit, thank you!).

That’s what the dealer who installed mine recommended and indeed he was very careful on more than one occasion to set it up that way, so that if pressed in it would return with a slight vibrating spring to it. The Naim dealer who sold me the Shahinians confirmed this tweeter setup.

Either both got it completely wrong or it’s simply the word bounce that isn’t er… resonating with either of you…

One way or another they sounded superb.

Nigel, what happens when you give your tweeters (obviously not the domes!) a very slight push? Do they move and spring back?

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Yes, when you press the box it should oscillate back and forth (no side to side rock or wobble) and the tweeter will give the impression of bobbing piston-like back and forth a few times within the cut out.

We’re talking about two completely different things here, as much as they are interconnected. Completely agree about the bottom box and leaf spring - I think everyone is. This is really just a question of the tweeter arm being positioned level and tightened sufficiently.