advertisement


Naim SBL

say it as it is

pfm Member
Ok finally got round to putting the SBLs back together , thanks to a fellow fish new drivers fitted and added bonus they look mint, quick question mk1 vs mk2 drivers how can you tell the difference? The original had shorter phase plugs and the connections are reversed? The ones I fitted have longer phase plugs looks like 2 part.

Grilles mine came with no grilles, so I knocked up a set of thin MDF frames and covered them in speaker cloth with velcro. They look very smart and fit well but is cloth and grilles ok? I had heard the foam was used to damp the tweeters somewhat any truth in that?

Cabinets look ok have new gaskets and pads to fit when I finally install them.

As I have laminate flooring on suspended chipboard floors I currently have granite bases that seem to work well home made efforts ( 2 heavy granite boards with bouncy balls cut in half so 4 between floor and first granite and between the 2nd granite board ) With the SBLs I was going to use the spikes in aluminium cups onto the granite. Hope this avoids the issues with the flooring as cured previous speakers.

last point crossovers. I am using these passive so original crossovers. I know there are very expensive upgraded variants out there, but is it worth removing them and having them serviced ie will they benefit from new parts or generally they ok?

looking forward to eventually try them at long last but rather get all the work done and install and set them up to try them.

any help or advice very much appreciated thanks
 
Great speakers, you can get foam grills made.

Other than that, leave them stock & enjoy them for what they are.
 
quick question mk1 vs mk2 drivers how can you tell the difference?

The Mk1 drivers have a lip around the edges:

maxresdefault.jpg
 
hi yes they have the lip round the edge as per the photo, they are mk1 I think yes makes me wonder what was fitted they also had the lip round the edge the cones have gone a yellowish colour and the phase plugs are much smaller don't protrude as much and sit much deeper into the voice coil ie you can not see the joint. Ones I have fitted were matched pair supplied to a fellow fish from a Naim dealer. The differences are the phase plugs are much longer protrude much further and you can see the joint exposed from the voice coil. Also the connection as you look at the speaker are reversed( stickers upside down and colour coding on the terminals correct to the stickers ) They look good as new makes me wonder as they came from a Naim dealer at the time if they were refurbished or factory upgrade did this ever happen? the serial number make them older than the ones I took out. Was there big differences in mk1 drivers then?

Its the phase plug that has got me thinking as they look like the mk2s i have seen

how do I put pics on here and see if anyone can clarify this?

thanks
 
2k7wHRB
2k7wHRB
these are what came off with the much short phase plugs

2k7wxwU
2k7wAFe
2k7wBNp
what i fitted with the longer phase plugs but still lip round the edges and serial number puts them older than ones I took out

2k7wD2M
2k7B42S
home made grilles
 
IMG_20201117_161309011[1] by Alan McGavin, on Flickr
IMG_20201117_161317381[1] by Alan McGavin, on Flickr
IMG_20201117_161327335[1] by Alan McGavin, on Flickr
these are what I took off with very short phase plugs that go deep into the voice coil

IMG_20201117_160246009[1] by Alan McGavin, on Flickr
IMG_20201117_160324024[1] by Alan McGavin, on Flickr
IMG_20201117_160334004[1] by Alan McGavin, on Flickr

these are what I fitted with much longer and 2 part phase plugs

IMG_20201117_160502871[1] by Alan McGavin, on Flickr
IMG_20201117_160523023[1] by Alan McGavin, on Flickr

home made grilles
 
If you can track down a pair of Mana SBL bases they were very popular back in the day. Quite a lot of pairs were sold so they do come up. I actually have a pair I got for a friend for his fyne speakers. He loved them but he's just bought a pair of bigger Fynes so they might be free again soon.
 
All the drivers in your photos are mark 1.

The "short" phase plugs are much too short, they must be the outer part only of the 2 piece plugs from the mark 2 drivers.

If your replacement drive units have 2 piece phase plugs they are mark 1 drivers retro fitted with mark 2 phase plugs ( that's probably ok but the mark 1 drivers only allow the plugs to be glued in place, the mark 2 units used a brass bolt through the back of the unit into the rear of the inner half of the plug to mechanically fasten them in place, perhaps to remedy phase plugs falling off! ).

Your grilles look good!
 
Hi all yes the plugs on the original just glued into place they were both detached when I got them. The plugs are solid no holes or other means of fastening. Strange one they definitely seem way too short.
Agree the replacement are MK1 cages but the condition is very very good any they are older but don't look it. Yes looks like retro fit phase plugs but as they came from a naim dealer many years ago I can only presume the dealer or factory have worked on them at some point?
Either way they look good and the grilles fit nicely the black id actually growing on me haha.
Ok recommendations on who to refurb the Xovers then?.
Makes me wonder if fabled mk 2 drivers are worth seeking out but fact this was a mint matched pair am happy to try them.
 
I had mk1 and mk2 side by side, mk2’s were better but I wouldn’t sweat too much, especially with nice matched mk1’s.

I had a friendly forum member build me nice PXO’s, always worth a shout out in the diy room, otherwise I have seen Class A modded ones in the distant past.
 
Naim went to great lengths to continue the SBLs when their original driver supplier (Mordaunt Short IIRC) stopped making the units. They effectively brought the driver manufacture in-house, made the design better in the process and relaunched it as the MK2 which was available as an upgrade to MK1 SBLs. There are variations in the cabinets too, with some (maybe MK2) SBLs which are veneered all round (including the backs) which are said to sound better. It's possible that these were just a different veneer/cabinet maker in their build history.
 
It's worth bearing in mind that the sbl gained its reputation on the strength of the original design.

Yes, the mark 2 unit was better made and engineered (I seem to remember someone on here once saying that Naim paid MS £8 each for the original units, much worked on by Naim subsequently of course) and I think it did sound better but that doesn't suddenly make the mark 1 version rubbish!

There are aftermarket passive crossovers that are reputed to be better but the only ones commercially available advertised to my knowledge are far too expensive to make any kind of sense. You've spent quite enough already without listening to them so I'd get these up and running and see what you think before wondering about further upgrades.

Later cabinets are reputedly better, veneered on all surfaces (including inside?) by a French cabinet maker that Naim sought out to build more sophisticated cabinets for their later speakers (Allae, SL2, NBL etc), but again probably a marginal improvement over what was originally considered an outstanding speaker (when set up and working right!).
 
well removed the crossovers well the black plastic box at least, it seems very well glued in, what best way to remove the pcb without damaging it to check the crossovers?

cheers
 


advertisement


Back
Top