Kudos X2 "boomy" bass

After a month of misfortune I finally got the kudos X2.
I first connected them to the naim nait2 (serviced june 2020) and I immediately noticed an excessive emphasis at the bottom, so I thought of connecting them to the CB NAP250 / HC / 62 (serviced December 2020) thinking of controlling the bass better but the result is the same.
So I thought about buying some bass reflex plugs and it should arrive Monday.
In the meantime I tried to insert a sock in the refelx duct and the situation has drastically improved, the bass is tighter and no longer “swollen and rubbery”.
Has anyone else had an experience similar to mine?

I have. I tried a pair of X2s here and experienced the same. My amplifier at the time was a NAIT XS. I really wanted to like them but couldn’t tame the bass. I expect you have tried to get them farther away from the walls. IIRC Kudos recommended placing them 2m apart with some toe-in.

My conclusion was that my room isn’t big enough. I’ve settled on a pair of SBLs.

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There seem to be some rooms where reflex loaded speakers simply don’t work. I’ve never been able to get them working in my room and have stopped even trying. PMCs were fine, but of course transmission line designs are different. For me, sealed boxes are so much better. In your profile it says you have Harbeth P3ESRs; did you try the Kudos before swapping? I’d imagine they could be a step down.


I placed them 30cm away from the back wall, and even if they sound good 1m away from the back wall I can’t keep them that far ahead.
i installed the spikes but it gave the same problem.
In any case, the sock has corrected the bass by far and being a straw, I believe that the sponges must work better.
Now everything is more balanced, the bass is tense and deep.

The trouble with bunging the port can be that it reduces a range of bass, not just the possible one or two notes that boom. Positioning of speaker and listener can make a huge difference, depending on what exactly is causing the boom.

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I have not had the opportunity to listen to them before and I took them in a poke.
I must admit that solved the bass problem I like them a lot and I prefer them to the P3ESR, paradoxically the voices are much more enjoyable with the Kudos

@ carruthersesq

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I recently got Kudos X3’s - which are a bit bigger than the X2’s. I don’t recognise what you say, at all. Currently running my X3’s on my NAP140 and they sound fine. No Bass problems - and I have them only around 100mm from the wall.

I have also run mine with my NAP250 - and again - all was fine.

YMMV… clearly.

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I’ve had my X2s in a couple of different rooms, one of which I would describe as difficult, with bass nodes around the room etc. and the other room being much better behaved. I wouldn’t describe the bass from the X2s as ‘boomy’ in either of these rooms. If there’s an exception, it would be when I first had the X2s and ran them from a Superuniti. There was a bass null in the listening position, and greatly exaggerated bass in the room corners. While these may seem like classic room acoustic problems, they pretty much vanished when I upgraded the electronics to NDX/282/200.

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Bottom line is that every room is different. I also had a bit of bass boom in my room when my Kudos 606 first arrived. I did some measurements using the minidsp kit and dialed down the bass frequencies (via Roon) that was causing the boom. No more boom :smiley:

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Twas always thus - better amp = better control = better bass.

starting from the fact that I feel the need for a remote control, do you think that switching to a NaitXS3 could be a downgrade?

For me it was the amp upgrade that made a big difference, in particular the 282 in comparison to the preamp in the Superuniti which it replaced. So I’m not sure an amp downgrade would help cure your bass issues. Still, there’s no harm in trying, but ideally you would want a home demo to try it.

I think there is something in that… and matches my experience… a speaker that is resonating with a room at certain frequencies will benefit from an amp that has greater power and exerts greater control over driving the speaker.

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Indeed, I’ve been lambasted in the past for suggesting that a preamp upgrade might cure room acoustics issues, but that’s the way it worked for me.

Your experience is yours. No further need for validation.

A lot earlier in my Naim life, Mike Creek of Epos once said to me, ‘It’s not speakers that boom, it’s rooms.’


My X2’s are also new, arrived with me on 30th Dec. I positioned them approx. 2.25m apart and around 35cms from the rear wall, they are about 1m away from corners. The TV is in between the speakers and the TV sound is actually played through the speakers.
The speakers are being driven by my Supernait 2 and I must admit being surprised initially by the bass response on first listening. Over the following few days I left the TV on a low volume over night to speed up the burn in and I also moved the speakers a few cm’s here and there but I think they just settled/burnt in and sound became controlled.
They remain positioned very closely to where they were first placed, maybe marginally closer together and I’m very happy with them and I can confirm I don’t suffer with bass boom.

I’d suggest giving them a good few hours to settle in and then re-evaluate then.


I’ve not had X2s but I did have a pair of C20s (similar design, but larger) driven by a Supernait and HiCap and encountered similar problems. I also ended up using port bungs, though eventually decided they just weren’t right for me and swapped them for PMCs. Oddly, the (closed box) active ATCs I now use don’t give me the same problems even though they are bigger three-ways with much more powerful amps. As others have suggested room/speaker/electronics interactions are very idiosyncratic especially in typical smaller UK listening rooms also used as family rooms with limited scope for acoustic treatment.

I hope the reflex plugs work well for you.


I have X2’s and also get some bass boom on some tracks. I definitely feel this is the room rather than the speakers. I may try the ‘sponges’ and see if that makes a difference.
May I ask the op what reflex plugs he has ordered?
I will be interested to hear your findings.
I will say though, on the whole they are great speakers. I hope you manage to find the right balance in your room.