SBL Bass distortion - Too Loud?

It does sound like a fault with the driver. I had a similar-sounding problem once (different speaker/driver) that was caused by a pre-amp fault (went into oscillation while playing at high level), and the heat had distorted the voicecoil causing it to rub in the magnet gap.  

If you heven’t tried Naim direct then that is an obvious place to try, otherwise I would try Falcon Acoustics, who are both knowledgeable and helpful. If a slightly different driver you may be better of changing the ones in both speakers to match. Otherwise try a well-known aution site for secondhand ones might be the only way (deive unit or whole speaker), though it could take a while before one comes up.  I don’t know how readily they are removeable they are for change yourself, but if not straightforward there is probably info to help on tne ‘net.

I should have added, there are specialised places that repair drivers, most commonly for professional speakers but no harm in asking. A search for re-coning is likely to find possibilities.

Have the SNAXO levels perhaps been set to reduce output to allow more realistic volume control travel than the commonly ridiculous restriction to the first third to half?

Is 3pm a typo, or am I misunderstanding what you mean?

Yes 3 pm no typo. My nearest neighbour is 1/4mile away. Well it was an exceptional journey past 12pm and typically I'm at 9-10pm. Its on vinyl so not a high level input like a CD, I guess as I only play vinyl through my 52 active setup. Interesting what you say about active vs passive but I don't think there is that an appreciable difference between the two.

It might be worth checking that the seal is intact on the affected speaker. Carefully push the bass/midrange driver (with pressure on both sides of the centre) inwards, release and see if it returns, fairly, slowly to its resting position. If unsure of what this speed should be - compare with the working speaker.

If you detect a problem - reseal the gasket, asking advice (before) if unsure.

Also it may be worthwhile checking the driver bolt torques - 3.6Nm. In the absence (quite likely) of an accurate torque wrench then just check by hand that they don't seem egregiously loose.

They DO NOT need to be 'Linn' tight - they need to be 3.6Nm. Do them up too tight and they'll compress the cabinet material and - loosen.

It's also mildly possible that an internal speaker cable is fouling somewhere BUT unlikely in a speaker that has been working fine and hasn't been transported or shocked/bumped. Getting in to check should not be done lightly as - it's a bit of a bugger and you need (the correct) hylomar sealant when reseatting them.

Is 3pm 1¾ turns of the knob (as opposed to just 3 o’clock?) 

11 AM was enough to move my chest hair inside my shirt--back when I had a 250. I've never had an active system, but it seems to me that you may be hearing the room as much as the  speakers and getting all sorts of echoes and rattles.

3pm? I use vinyl mainly and never get past 11.30. It’s just too loud. 252 300 SBLs here. On cd I never get above 10. 10 and 9 respectively are more typical and even that can be pretty loud.

Good shout above on checking the seal on that speaker. However, 3pm sounds very wrong to me. Can you get your dealer to check things out?

Stu

stuart.ashen posted:

Good shout ....

:-))))

To the OP, sorry I can't help. I loved my SBLs. Yours is a brilliant username btw.

A few folks, including myself, have noted that in going active you lose "about an hour" of volume. 

Having said that, with active SL2s, I don't think I've ever achieved 3pm! 1pm not unheard of (see what I did there) and maybe on occasion approached 2pm but never 3pm.

Willy

Ps for the record my neighbors are also suitably distant and several of the internal walls are 2ft thick so I can do that whilst Mrs Willy is asleep upstairs at the other end of the house. In some way compensates for the maintenance pain in the arse that an old stone built house is.

It might just be a lead wire from the coil rubbing or just touching the main cone itself when the volume is cranked? worth checking if it's an easy thing to do...maybe ask a dealer to check them out?

Saying that, one would of thought that cranking the volume to 3pm (even active) would be on the verge of taking the tweeters out, regardless.

Hi .... just a thought on oldish speakers ........ the cones sag slightly with time ... altering the gap at the voice coil. I suggest removing the drivers and rotating them by 180 degrees ........ then run as normal and give it a little time it may help....hopefully the will settle back in.

If I ventured - to 3pm on my 552 my speakers would explode........mine is at about 90 dB at 10 o'clock.  Use a db meter on your smart phone....to see what levels you are attempting.... 

Richieroo posted:

Hi .... just a thought on oldish speakers ........ the cones sag slightly with time ... altering the gap at the voice coil. I suggest removing the drivers and rotating them by 180 degrees ........ then run as normal and give it a little time it may help....hopefully the will settle back in.

 

Won't his soundstage be upside-down? 

When I had setup my active Ovator 600s, I did a test: a full prelude + fugue (organmusic) for 10 minutes on full open volume dial. I could only see my wife talking to me on 50 cm distance. Then I decided that the setup was proper.

Before that, I had months of setup hassle. It were active leads and fraim floor protectors which did the ultimate trick.

Make sure the loudspeakers are absolutely stable.

5TooManyBikes posted:

Is 3pm a typo, or am I misunderstanding what you mean?

Yes 3 pm no typo. My nearest neighbour is 1/4mile away. Well it was an exceptional journey past 12pm and typically I'm at 9-10pm. Its on vinyl so not a high level input like a CD, I guess as I only play vinyl through my 52 active setup. Interesting what you say about active vs passive but I don't think there is that an appreciable difference between the two.

 

 

Tinnitus and bleeding ears here you come. 10.00 is my limit, timid creature that I am

Seriously - you need to understand what levels you have come accustomed to..... with a good system such as yours it will play cleanly very loud. However, assuming you value your hearing - I would have thought - you would be looking at average levels well under 95dB. I tend to like things loud - and find mid to high eighties plenty loud enough. a long session at over 85dB is not great for your hearing. Do a test - it may be your speakers protesting .... always one will give up before the other .... a bit like your hearing!!!!!

Regarding the distortion, I reckon it's worth removing the driver screws in the left one, rotate the driver through approx 180 degrees. I had an issue with a pair of elderly Road The Minstrels and turning the driver through half a turn allowed the cone to "re-centre" It's go to be worth a try.

I used to have SBL's and also when playing vinyl would sometimes crank it up to similar levels, on one occasion, full... Now though, suffering from tinnitus  (I wonder why??) I keep the volume to more sensible levels!

Thanks for the advice chaps. I shall look at rotating the driver perhaps. On my hearing listening at V LOUD levels is an exception. It's just that George Benson, Ron Carter and Herbie Hancock playing white rabbit just needs to be loud. Wen Al Green or teh O Jays go on it is much quieter.

I'll look at a db meter as well at 1 metre.

It might just be a lead wire from the coil rubbing or just touching the main cone itself when the volume is cranked? worth checking if it's an easy thing to do...maybe ask a dealer to check them out?

I'll also check this advice. I'm sure it is something simple; fingers crossed eh.

Try isolating as much as possible first.

I had a similar problem which turned out to be interference on one of the 24v rails from my hicap feeding my naxo, which showed itself in my right sbl.

You've already swapped naps with no change.

Have you still got the pxos for the sbls?

If so, remove the active components and then see if it still happens.

Swap PSUs, cables etc.