SBL Drivers Shot-Help!
Posted by: mikeybaby on 19 January 2016
My SBL Drivers are Buzzing. I tried having them repaired all to no avail. They buzz with certain frequencies of the piano. I have a pair of Credos and SBLs. After comparing the two There is no contest.... The SBLs walk on them even with the upgraded crossovers. My question is this: Can I simply put the Credo drivers in the SBL? I know its been said that "physically they are the same driver but selection and matching a bit different." What does this mean?
Mike,
do you mean the scan-speak tweeters?
or do you mean the mid/bass drivers?
Debs
bass/mid
Are the silicone seals between the lower and driver-box cabinets okay?
Perhaps they may just need resealing?
Yes they are ok. I pressed the woofers in gently and they slowly returned to their normal position.
So can I use the Credo bass/mids?
mikeybaby posted:So can I use the Credo bass/mids?
I dunno if Credo type drivers are the same.
Are your SBL drivers the original mk1, or later mk2 version?
What actually was involved in the attempted repair?
It would be worth checking the x-overs:
Take the covers off and check the naca cable wires are securely soldered onto the circuit board.
Mk2...Reglue applied to outer edge of cone. Crossover wires were inspected and passed.
Have you checked the split phase plugs? They also act as heatsinks for the coil and heat generated from the driver can dry out the plastic dowel and sticky gasket ring that holds the two parts together. This could be the source of the rattle or buzz. Naim can supply a new dowel and ring kit.
SBL drivers were carefully selected and matched. AFAIK Credo drivers had a wider selection criteria and were not matched.
The split phase plugs were reglued....SBL drivers will cost me 1000 dollars. Ouch!
what is a good replacement for these speakers? The Credos sound a bit harsh with the olive 82/2HC/250/CDS2.
My Naim dealer doesnt stock any Naim speakers but he has Focal. Worth a try?
Richard. My crossovers are also on the way out. Can I use the the CXO crossovers from the Credo on SBL?
I did an experiment and to me I thought the CXOs lost a hair of detail.
The CXOs from the Credo aren't supposed to be used on the SBLs.
If you like what SBLs do then there's not much else out there that can compare apart from another pair of SBLs, SL2s, or DBLs.
How about the C/overs from SL2?
If you are having problems with crossover, this is just God's way of hinting you should go active.
Thats my helpful comment of the morning, btw :-)
Yup, others on here have successfully used SL2 crossovers on SBLs.
However, I think I like the sound of Jon's idea even more...
I will look into it. Thanks!
SBLs active are on another plane of performance compared to passive. This is exactly what you would expect with a speaker which is inherently very transparent. The passive crossover is akin to having a cart and horse between you and the music.
Jon
How do I go from passive to active?
82/250/2HCs/CDS2/SBL
mikeybaby posted:Jon
How do I go from passive to active?
82/250/2HCs/CDS2/SBL
Buzz is first priority, no?
C.
Richard you mean the beige ring around the phase plug might be the culprit?
Yes I think I am going to replace the mid/bass drivers.
The vibration is very slight but is bothering me.
The ring is adhesive that sticks the two parts of the phase plug together. However with age and heat, the adhesive weakens and dries out. The dowel also shrinks and allows movement of the end piece. In extreme cases the ends can fall off. If the end piece can move then it may just be the cause of the buzz. Either way, it's relatively cheap to fix (Naim can supply a dowel and adhesive ring kit) so has to be worth doing.
mikeybaby posted:Jon
How do I go from passive to active?
82/250/2HCs/CDS2/SBL
I doubt whether going active would cure the buzz. Although tired crossovers can cause something similar I'm told.
If you did go active however you'd need another Nap 250, a naxo 2-4 or snaxo 2-4 or snaxo 242 (active crossover) and two more runs of speaker cable. If you wanted to keep the 2 hicaps on your 82 then you'd need another hicap also to power the naxo/snaxo or you could save money and use one of your existing hicaps for the crossover. And 1 or 2 more power sockets of course. You take the existing passive crossovers off of the SBL's and the NAPs wire directly to the sockets that the wires from the passive crossovers used to go to. The naxo/snaxo sits between the 2nd hicap and the naps. i.e. 82>hc>hc>snaxo>250's>SBLs. Voila! Box fest. But the sound is fantastic. Hugely dynamic and exciting.
BR, Mark.
When I put my finger on the cone while piano is playing the buzz stops. Piano notes are the only frequencies that cause buzzing.