Naim Chrome Bumper

There are 6 drive units in each Isobarik speaker. Another mid and tweeter sit on top and fire upwards and there is a second bass unit inside the cabinet in line with the visible one.

2 NAXO 3-6 in like a stereo setting? Each one looking after each speaker, could that be done?

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This, basically… If I have to have mono leads made up to run them as NAP 125s, then so be it, but I’d like to try and get them working in stereo.

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Dare I say, I ran my Isobariks in a period with one Nap 140, even a Nait 2. :sunglasses:

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6x250 is a massive installation, too much cables :slight_smile:

I’d like to have a picture of the cables dressing🙂

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I currently have an olive NAC62/HC/NAP140 and recently paired them with a set of Fyne F501’s - a match made in heaven for the setup I think.

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Question about the chrome bumper part of the chassis…

If there is rust or discoloration on the “chrome” is the solution to sand it down with steel wool or paint over it? In other words, did the chrome come from having sanded it down to the raw metal beneath, or was it a silvery paint that was applied to the chassis?

It is raw metal. I imagine that the chassis was painted and then the front ‘bumper’ sanded down to reveal the ‘chrome’ (it is actually an aluminium alloy I believe).

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I think they are extruded aluminium and simply cut, leaving the bare ally finish

Others will know better, but it is either bare aluminium, or the same aluminium polished and coated with say a lacquer.

Aluminium does corrode, and quickly too in an oxygen rich environment. But this passive oxide layer also protects against further oxidation/ corrosion.
However its not as bright as the bare aluminium. Hence, if polished, any lacquer would need to be applied quickly.
My guess is that naim did not go to the expense of lacquering. But I’m guessing.
If they did not, then I’d take a green scouring pad and lightly rub, in one constant direction, to remove any marks and expose fresh aluminium. Brush with the exiting brush marks.

One thing for certain, it is not chromium.

I wonder how many have, or have thought about, sanding down the front face of the sled on their Olive gear…

I did think about it. But only from the position of " what the difference is" between the two.

Happy with my Olives.

Absolutely. I love my Olive gear too abs it looks magical in the dark too.

Easy to convert to the CB look I have an Olive 52 PS converted to Supercap for my 32.5 and I just took the cover off and hand sanded the edge with a block and 80 grit to match the course finish of the other CB power amps looked a bit brighter for a week or so, now identical no lacquer used

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TimD You need 6x135’s :wink:, not sure if just disconnecting one channel is the same ?

Well I am amazed. I was a Linn dealer, mad for active, and never have heard of split Isobariks. Thinking of your schematic, I don’t think you need to modify the SNAXO, just get the leads for each of the 6 outputs (the ones used for 6 x 135s) to split into two cannons, and thus feed each side of the 250s. The schematics on the back of the SNAXO and the 250s will guide you.
I am guessing the splits came out before 135s were available. Or after Linn went their own way with amplification. Their LK1/2 was OK but didn’t really have the oomph for Isobariks, (IMHO), so maybe this was their fix. I will have to hit Google

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Your post reminds me of a readers system in one of the UK mags, quite a few years ago now. IIRC it was a Linn system using 12 LK series amps powering fully split Isobariks. The gentleman whose system was being covered in the article was trying to create the wall of sound he and his wife had experienced at a New Order concert…

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Just using Dr Google, there is some chatter on splits. I had forgotten the passive crossovers were basically two independent circuits. Last time I was grovelling around inside an Isobarik was about 35 years ago. Time flies. But I still remember how difficult it is to get the bass drivers out.
But looking at my old SNAXO rear plate I can’t see any problem with the wiring up.
As for recreating New Order, well… as much as I loved my PMS system, I know that no matter what you do the SPL of a live concert is beyond their reach. I think the better stereos actually sound clearer than concert PAs, (if you dare plug an electric guitar of microphone into your hifi and be very amazed. I have an opera singing friend and … WOW. Just be careful about dynamic range). But as for moving air, nothing can match huge bass bins.

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Yes, splitting makes sense with 'Briks – at least, the ones with two Xovers in the base – because it changes the passive version into two eight-ohm speakers in each cabinet instead of a single four-ohm one, so easier to drive. You then use two stereo amps to drive them, or a single stereo amp if you common the two passive inputs. The splitting was a third-party modification.

Just need one more CB NAP 250, and I’m there…