hey guys, my friend recently purchased a NDX2+SN3 and is uses a B&W 804 D3.
he was having a party the other night and cranked the volume passed 12 o’clock.
he complaint that the the SN3 suddenly stopped playing for about 5 seconds and the lights started blinking, then it continued playing.
since then, he’s stopped playing at that volume.
he also mentioned that he when he tried the mark levinson and hegel amps, he could push it pass half way up without tripping.
your thoughts guys?
If the top of the SN3 is almost too hot to touch when it dies it will be protecting itself and cutting out before any thermal damage is done. If my memory is correct this feature is described in the manual.
My Nait 5i came with exactly the same issue after extended periods at “party” volume. I replaced that with an SN2 which had the same problem, but sounded fabulous. I then added a NAP 250 DR and the problem transferred over to it… but things sound AMAZING!
As these things are passively cooled, my workaround is to have a small clip-on fan gently blowing over my NAP 250 DR if things are likely to get raucous. That seems to have negated the problem and the top of the unit never gets too hot now and the fan is barely audible… especially at ludicrous level.
take care on your hearing though. from my own experience with my handed me down NAC52, 12 oclock is really loud. maybe your friend would benefit from the NAP250 or NAP300. just curious what songs were you guys playing?
12 o’clock on a SN2 is brutal!
I can’t recall a time when my NAIT’s ever made it to midday for any length of time. That’s got to be pretty loud by anyones standards surely?
It sounds very much like it’s protecting itself from terminal damage on this occasion.
Maybe hire a PA system next time 
My CB NAP250 would do this at the slightest hint of a party! Replacing it with fan cooled 135s solved the issue completely. I’ve never had any trouble with my Nova which seems to have decent heat sinks.
Any decent amp should be able to rock out without conking out!
That would make a good T Shirt 
A bit like dying at an old age, but from something you’d do as a young man.
I’m in bed by 10 most days!
Might need to do a version tuned to my particular circumstances, namely, “Dad Out without Conking Out”
I own a Supernait 1 and can not imagine putting the volume past 12 o’clock.
The only reason I can think of is that his inputsignal is far to low.
Enjoy listening
Theopa
I used to have a CB NAP 250 that would heat up and shut down at higher volumes. I then had a Superuniti that would also shut down when I really pushed it, but it would take more abuse than the CB 250.
This would happen after about 10 minutes of enthusiastic playing, and I didn’t play much more than that, at that volume.
As Mikey did, I ended up putting a small computer fan beside it that blew across the top and bottom, and the issue went away.
My SN2 has never shut down.
Dave
Me can’t help thinking that going past 12 is pretty loud into most loudspeakers. And even if it is getting hot, I’d expect a little SN to be well into clipping, and sticking dc into the speaker voice coils. Which they don’t like.
My power amp is a bit of a beast. My daughter managed to destroy a pair of Ruarks during a party. The voice coils were melted!
Of course it was not her fault.
There was a happy ending as I sold the cabinets for more than I paid and was forced to by my first set of PMCs.
Thermal protection only occured to me many years ago with Nap 140.
I imagine that 12 'o clock or beyond with an avarege modern recording and digital source is absolutely way too loud. With Nait XS the sweet spot is at 10 ’ clock and with 552/500 at 9/10 'o clock. However some electronic music or indie/wave is tripping the 500 fan quite easily.
Regards
Roberto
My SN2 only shut down once and I did have the music cranked for a couple of albums when it shut down! I called the dealer and he explained the auto shut-off feature and the unit did come back to life.
It was a Friday afternoon/evening after a long week of work and the house was empty, no party just a bit of mania…
Love the SN2 and do not have an issue with the safety feature.
It seems a bit odd that the amp shut down for such a short period if it was overheating (even if overheating isn’t that surprising if you work it that hard). You would expect it to remain off until the internal temperature had recovered. Was it the CD button that was flashing?
Hi NMB,
The SN3 has two protection states - flashing CD input button = over temperature & flashing Tuner input button = over current.
I suspect in this case it was over temperature.
Using any non fan assisted Naim amplifier at those kind of levels will likely make it overheat, assuming that the source is ~ 2V output level.
As has been said, the output is likely clipping and sustained use will cause damage to crossovers/drive units. Clipping will occur even if fan(s) were keeping temperature levels down.
Obviously it can be tempting when a little oiled by the booze wheels to push it - but it does seem like hi-fi suicide in the cold light of day.
I’d politely suggest that your friend should consider a dedicated party system!
Using the volume knob position as a benchmark as to how far you can push an amplifier across different manufacturers is really not very scientific!
Regards
Neil.
Hi Chris,
It’s feasible that transients at those kind of levels may have triggered the over current protection, which as you say would be a shorter interruption of the output.
Even so, see my above comments!
Regards
Neil.
Edit: admit, I skimmed over the 5 seconds bit!
Many years ago at uni someone in my house had a rega tt/ Cambridge audio amp / mission speakers (iirc) and that thing could be pushed to maximum volume! Not that we could stand it of course.
With my current sn2 I can’t get anywhere close to 12 on the amp, it’s far too loud. 10 yes, 11 is probably the limit.
I’ve only ever pushed my SN3 to 10 o’ clock maximum and that was really eye watering loud! I suggest your friend has their ears checked out and have them syringed by the local nurse!
IIRC the original 800D series speakers had a complex crossover that initially caused Naim power amps some problems and would regularly trigger the protection circuit quite early on. It led to Naim making a modification to the protection in the big amps. However, it might suggest that the 804s are perhaps not quite as benign a load as their nominal impedence suggests. Certainly running such a speaker at those high levels I would expect it to be working very hard indeed, and in hot environmental conditions cooling may well have been an issue, but as Neil mentions above, current protection can’t be ruled out either.