System advice

Octave always gets stellar reviews with the caveat that, especially for tube amps, they have a relatively neutral sound.  If that’s what you’re looking for Octave is obviously a strong choice, but at those prices there are probably other options as well so might wanna look into what else is out there in that range.  That said, I’m sure that Octave gear with the Pulsars would sound stunning as it should at those prices. 

I think the Octave has plenty of tube magic, but the only question is if it has enough warmth as it tends to sound more neutral.  The Octave won’t sound thin or sterile by any means, but If you’re looking for an amp to add warmth it may not be your best option.  But that’s a personal taste thing.  

Yeah the way they listed the specs was confusing as they listed output as “low” and “high” that I didn’t realize was pentode or triode.  I’d have no reservations in pentode, and it might even work in triode for most music/situations. 

Don’t know what PA is.  I love Octave and would own it myself, but at 75 Wpc I’d be a little concerned if it has enough power.  Also, from what I’ve read of Octave their house sound is on the neutral side as tube amps go but that may work for what you’re looking for.  Personally I’d like at least 100Wpc on tap, but depending on the design of the Octave it may still work.  Personally I think that Octave would sound magical in your system as long as it has enough power.  Another one I would look at would be the Unison Unico 90 that’s a hybrid and was recently reviewed by Michael Lavorgna…

https://twitteringmachines.com/review-unison-research-unico-90-integrated-amplifier/

Really depends on what sound characteristics are most important to you.  I know you’re looking for better bass, but a lot of amps will easily give you that.  And I think you’re finding the sound a little on the bright side?  Anything else?  Also, where would you be buying the amp from and what’s your budget?  Are you only buying used?

However, when it comes to rock, it’s quite poor; the sound becomes flat and chaotic, with a heavily veiled background. I’m wondering whether the charm of tube DACs is limited to the types of music I mentioned, or if this might be revealing the weakness of the very old power amplifier I’ve connected this very expensive DAC to....?

If it’s the amp I think it is it’s like an $800 amp that has no business being in a system with the Pulsars and Lampi, and I believe it only puts out 70Wpc so that’s your problem not the DAC or speakers.  You also need a much better preamp or a better integrated amp.  The chain is only as strong as the weakest link, and your pre and amp are a total mismatch for your new equipment.  

There doesn’t seem to be as big of a difference between the original and Pulsar 2 as with the Perspectives, and some even seem to prefer the original so I’d have no problem going with the original Pulsars and save the $$$.  Once you hear them you may feel no need for the upgrade, and I probably wouldn’t even bother doing it as the originals are so good.  The Perspectives are a different matter as the improvements in the Graphine version are more significant.  You can probably order Pulsar grills from JA and certainly worth checking into, but I’d negotiate with that seller for a lower price to recoup at least some of that cost if possible.  Sitting 4 meters from them isn’t a problem, but not knowing your room size it’s hard to say if they’re enough for your room, but if the Platinums were ok then the Pulsars should be fine too as they put out considerable bass for their size as you’ve probably seen from reviews.  The ProAc K1 is worth looking into if Pulsars are hard to find as it likely offers similar sound characteristics — just another potential option.  Hope this helps. 

I am a fan of JA speakers in general as they manage to sound very natural and musical while not sacrificing air/detail, and they also disappear and throw off a 3D soundstage better than most anything else I’ve heard.  I haven’t listened to Dynaudio speakers in too long of a time to say anything directly about how they sound now, but what I’ve read about them from reviews and owners would coincide with your impressions and is why I thought the Pulsars would be an improvement.  I also think ProAc is right up there with JA and are probably a lot easier to find/buy in Europe if you may need/want another alternative.  Hope that helps. 

Upon reading some reviews of your speakers I can see why there could be an issue with glare or an over abundance of detail in the upper mids and treble and may be what you’re hearing.  You could try these Joseph Audio Pulsars (original version) that could be much better/more refined in that area but not lack for transparency like the Dynaudio speakers — best of both worlds of you will.  If you buy well and they don’t work out for some reason you should be able to sell them for little/no loss so not a lot of risk, but I’d bet on you keeping them.  Just one idea FWIW. 

https://www.ebay.com/itm/186915696094

It’s good that you really appear to know what you like. If your Arcam stuff is that old I’d upgrade the pre/amp first and get that right because it may affect which direction you might wanna go with a DAC, and there will be other used Lampi DACs available in the future if that’s where you end up wanting to go so there’s no real need to rush on that important decision. And yes I’d be hesitant to drive your speakers with a 30W amp, but you can try it with your music at the dealer and see. If I’m you I’d give that Octave a serious listen and if you like it (or the Ayon) borrow it and see what it sounds like at home, but I have a feeling that might be a great match for your tastes and speakers. And again, once you have that sorted then see which direction you wanna go sonically with a DAC. Getting a DAC now would be a big shot in the dark at this point, which is why I’d wait on that. Just my $0.02 FWIW.

How does the system sound since you put the Arcam gear back in?  What DAC are you using now?  What specific improvements are you looking for over what you’re hearing now?  All important info to make any recommendations.  That said and without knowing anything more, I’d be inclined to upgrade the amp/pre first assuming you wanna do that anyway and go from there.  I’d be concerned the Ayon amps don’t have enough power for your speakers, but the Octave could be very interesting and I bet will sound great with your speakers, but it ain’t cheap unless your looking at a used unit.  I’d definitely demo the amp that sounds best at the dealer at home before making any decisions and deal with the DAC later.  Be interested in your thoughts once you hear the amps.  

Should I buy Lampi and then try to match up a amp to it or the other way around?

Since you liked the sound before with the CD5/Arcam combo I’d try to get that sound back in place first and then try a DAC, which could well provide significant improvements.  Which DAC will depend on what specific improvements you’re looking for at that point, but I’d get the base system squared away first before throwing another variable into the mix. 

Chalk this up to an expensive lesson learned — never just blindly follow a salesperson’s (or anyone’s) advice because your ears are the only thing that matters.  A good dealer should let you borrow equipment for a day or two to let you hear it in your system, and in this case that would’ve told you everything you needed to know.  Time to start over and get rid of the Naim amp/pre so you can start enjoying music again.  Obviously Arcam is a good place to start, but their sound could’ve changed over time so again don’t just buy blindly.  Luxman and Parasound were mentioned and would also be worth exploring, and I’ll add Ayre as another good candidate.  I’d try to get an amp with at least 100Wpc to make sure you have enough headroom for your speakers.  Best of luck.