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Which brand of Capacitors do Naim use?

hp1 said:
Would it be the front or back end of the nap amplifier circuit that is most affected by the regulator?
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Front end. Lots of the alternatives (Voyager, NCC200, HackerNap ...) use some measure of extra regulation for the front end, and run the high current output stage from a raw rectifier/capacitor supply.

I've never seen the circuit for a NAP300 or 500, but understand that they have separate regulated supplies for the front-end.

A brave (or foolish) 250 or 135 owner could do the same thing; this would probably cure (or at least bypass) many of the drawbacks of the regulator design.
 
MY NAIM IS GR8T said:
Having just had my two 250CB amps serviced I dont actually see any improvement in what I am hearing. I had a few resistors that obviously had seen better days (cracked) nothing obvious was wrong visually.
After nearly 30yrs it seemed a good idea to have all the recommended parts replaced.
Would I spend the same money again.......nope.
If there is nothing obviously wrong with your kit I would spend the money elsewhere.
It may be a better option only to overhaul a pre amp, but again I think not. I have a 72 pre and a 32, both are getting on a bit now, I have done plenty of back to back comparisons with them and I would say there is barely any difference in what I hear between the two.
If it aint broke dont fix it.
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I'd suggest you have the 72 serviced. Your not noticing an improvement afters servicing power amps due to the pre amps being in need of a service.

I had a similar experience but the other way round, I replaced various capacitors in my 62 without achieving much improvement, when I replaced the old tantalum caps in the power amp with new tantalum caps there was a massive leap in improvement. The 30 year old caps where holding back the whole system.
 
Adding to what fatcat has written. I recapped my NAC72 and NAP140 at the same time because they had begun to sound erm… ‘flat’ (though still very nice and certainly good enough to impress people with ‘lifestyle’ systems). I like the ‘Naim sound’ (i.e. I didn’t want ‘improvements’) so after extensive research (most threads linking to pfm :)) I replaced my tants with good quality modern equivalents (Kemet & AVX) because the original blue (NEC?) were unavailable. The (red) roederstein electrolytics were also unavailable, again after research (again most threads linking back to pfm) I purchased nichicon KZ (Muze). The Naim sound I originally liked was back……big time, the improvement was not subtle.
 
fatcat said:
I'd suggest you have the 72 serviced. Your not noticing an improvement afters servicing power amps due to the pre amps being in need of a service.

I had a similar experience but the other way round, I replaced various capacitors in my 62 without achieving much improvement, when I replaced the old tantalum caps in the power amp with new tantalum caps there was a massive leap in improvement. The 30 year old caps where holding back the whole system.
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I currently have a a nait 3 & cd3.5 from '96 & '97 , they sound great, how can you tell if they need a service, it is quite expensive also through Naim with the original Naim parts.

Even through a couple of other dealers it's not a lot less.

What benefits in sound improvement would be heard after a service with this particular equipment in your opinion.
 
The PRT never left, but had (over the years) become subdued. After the re-cap PRT back as before (at least as I remember), I also regained (big time), dynamic contrast, 'joie de vivre' and a 3D soundstage! (although only with vinyl).
 
finkaudio said:
I don't know about the blue ones, but the "modern" yellow ones in NAIM units are not Kemet....

ATB KH
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I suspect they are since their marking system is completely consistent with Kemet apart from the omission of the K.

Probably been "unbranded" to order.
 
I do not understand why replacing a tantulum capacitor would change the sound significantly, they do not "wear out" as other electrolytic capacitors do as there is nothing to wear out, they do fail but since they invariably short circuit its quite obvious when they fail.
 
Years ago Naim used yellow STC tants and they are definitely best replaced, and the system sounds a lot better for it.

I've never experienced any sonic benefit from replacing the late 80's/early 90's red ones or the later blue ones, but they do get replaced in normal Naim factory servicing.

I suspect it's just that they become more prone to failure as they age, but I didn't bother changing them when I recapped my SC since its a lot of disassembly for no obvious benefit.
 
colasblue said:
I've never experienced any sonic benefit from replacing the late 80's/early 90's red ones or the later blue ones, but they do get replaced in normal Naim factory servicing.

I suspect it's just that they become more prone to failure as they age, but I didn't bother changing them when I recapped my SC since its a lot of disassembly for no obvious benefit.
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A few years ago I had an olive XPS serviced at Class A (official Naim service centre). When I spoke to Darren concerning the cost, he offered the option of a part service, which involved not replacing the main reservoir cap but only replacing the tants.

I doubt Darren would be offering to only change the tants (blue ones) if there wasn't a noticeable sonic improvement in doing so.
 
Ragaman said:
I currently have a a nait 3 & cd3.5 from '96 & '97 , they sound great, how can you tell if they need a service, it is quite expensive also through Naim with the original Naim parts.

Even through a couple of other dealers it's not a lot less.

What benefits in sound improvement would be heard after a service with this particular equipment in your opinion.
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I remember speaking Naims service department concerning the service of a 62 and Nap90. They described the improvement as reinstating the sparkle that had been lost over the years.

Just looked a photo of the Nait, there are a lot of capacitors in there, although not all will need replacing, some may be associated with relays. I can imagine it will be expensive to service.

All depends on how much you value sparkle.:)
 
fatcat said:
I remember speaking Naims service department concerning the service of a 62 and Nap90. They described the improvement as reinstating the sparkle that had been lost over the years.

Just looked a photo of the Nait, there are a lot of capacitors in there, although not all will need replacing, some may be associated with relays. I can imagine it will be expensive to service.

All depends on how much you value sparkle.:)
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Sparkle, yes that’s it. My amps have their sparkle back. :)
 
digestive said:
Sparkle, yes that’s it. My amps have their sparkle back. :)
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Mine sound smooth, crisp, attacking & vibrant, maybe the "sparkle" would add brightness which i'm not too concerned with, could be why I love the sound as it is now so maybe best leaving it alone as there is no going back.
 
Ragaman said:
Mine sound smooth, crisp, attacking & vibrant, maybe the "sparkle" would add brightness which i'm not too concerned with, could be why I love the sound as it is now so maybe best leaving it alone as there is no going back.
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Erm…... no. Definitely not brightness. Struggling for the correct terminology. Joie de vivre/sparkle. But hey, if you like it as it is and have not become dissatisfied. Don’t change a thing. Just Enjoy. By the way, I kept ALL my original parts. JUST IN CASE. ;)
 
Joie de vivre is definitely not missing so I imagine having a service would be fruitless & costly though I have nothing to compare it so could think differently if I had.
 
Another thing wrong with the Naim regulator circuit (although this applies to amplifiers too):

The integrating capacitor is connected to the wrong point - the collector of the gain device. If it was connected to the output terminal, the output devices are included inside its feedback loop, so you no longer get output impedance rising with frequency, but a low constant impedance.

The compensation will need to be recalculated, as the slow output devices are now inside the inner loop, and so phase shifts will need careful watching.

At this point we should have a regulator that works well right across the audio band, and well above.

I'll try running something up in the simulator when I have time.
 
fatcat said:
A few years ago I had an olive XPS serviced at Class A (official Naim service centre). When I spoke to Darren concerning the cost, he offered the option of a part service, which involved not replacing the main reservoir cap but only replacing the tants.

I doubt Darren would be offering to only change the tants (blue ones) if there wasn't a noticeable sonic improvement in doing so.
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I think Naim servicing is a whole lot more about being a money making scam than sonic improvement in most cases.

The big BHC and SLCE/Felsic caps in power supplies and power amps don't really go off unless they get hot. XPS's HC's & SC's don't get hot so should last a very long time indeed. The tants in the regulator circuit aren't in the signal path at all and have very little effect on sound quality.

Never observed ant benefit at all in changing power supply tants in isolation, signal path tants (particularly yellow STC) yes but power supplies - nada.

My recently acquired 30 year old 135's certainly didn't actually need any servicing really. They got some but only to component match them to my other ones. In my view this makes the Naim 8 year recommendation highly questionable. I think it's mostly based on the particularly poor lifetime of the 10uF 63v BC components cap they put on the 250/135 regulator board.

There is definitely some benefit in servicing power amps which have run hot because they genuinely need it.

A lot of the benefit of servicing pre amps I think derives from the replacement of poor quality components with better quality ones. I know people rave on about maroons but they aren't that good to my ear, and those gold ROE and SLCE caps that went into the olive wide box pre's are truly questionable. The ROE's sound veiled and the treble from the SLCE's is very harsh.

Kendeil 22000uF make a big difference to HC's but curiously very little to SC's or power amps.
 
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