It is actually voltage what amplifiers deliver to speakers, not current.
Actually it is both!
NAP 300 spec says transient power capability is 500VA
NAP 500 spec says transient power capability is 700VA
NAP 350 spec says +/-42 amps peak (1.7kW peak power).
So on paper it would appear that yes, the 350 can deliver more current to demanding speakers. This is why when I furst heard about the new range I felt that the 350 is the Naim amp I would be interested in hearing, whereas I was uncertain as to whether the 500, let alone NAP 300, would be adequate.
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So donât you control for the number of variables by changing one thing at a time?
Do you know the transient power capability in VA for the Nap 350 ?
Thatâs not surprising at all, you have to get pretty high up the OC separates range to best the NC in my experience. Hard to say what contributes to the improvement, the lower noise floor seems to be a big contributor.
Sure you compare same specs? 350 also talk about burst power.
Burst power 2 â 610 Watts 2Ω @1% THD+N
So we have transient power, peak power and burst power. Confusing.
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Yes there is some current but it is negligible, what controls movement of speaker drivers is the varying voltage levels across the frequency spectrum. The amperage is used by the amplifier to produce the voltage.
Yes absolutely but my answer was just in respect of the OPâs question.
Where I absolutely do enjoy the technical details about the power delivery (and by all means, do try to get to a consensus about it!) perhaps what I was trying to ask is what amp would drive âdifficultâ speakers better: the 350 or 500? And even better, which ones have been tested!
The 350 peak power 1.7kW is quoted into 1 ohm, which means as stated above a theoretical 42A current output (P = I2 x R 
)
Of course under normal listening conditions the amp wonât be pushing a fraction of that, perhaps only a few W. Here, as you say, current would be negligible.
Those who like a bit of volume (say 80dB+) will start to push into the headroom for peaks. Orchestral climaxes for example may hit 100dB+ peaks and at this point somewhere towards the full (rated) power output of the amp may be utilised, depending on speaker sensitivity.
There are websites with reference tables of volume level (dB) against speaker sensitivity and amp power (peak). But youâd have to push the 350 very very hard with an unbelievably demanding load to get anywhere near that 42A, I think weâd agree!
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At a recent Naim evening their reps were pretty clear - new 500 series is 3-4 years away and the 552 is hard to improve . I guess that is backed up with why the 500 series being given white lights!
Gary
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That is my feelingâŠâŠthe S1 is a great upgrade, but at 3 times the price. You can make a preamp sound different, but betterâŠâŠ
And the technical specs tell you that, as I summarised in my post!
Although the wording is different I would take it as 1700VA.
Into 1 ohm though?
Yes and I believe 500 is at 2ohm meaning it would double into 1 ohm. No speaker load go this low anyway. So Iâm guessing itâs more 850VA vs 700VA 350 vs 500 into 2ohms.
Specs donât say anything if they are not complete and comparable. Marketing often lay their hands on such and have no clue what they mean. As long as the new box have a higher number it must be better 
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The 24 bit Telarc recording of Tchaikovskyâs 1812 (recorded in 2000) is impossible to play with the orchestral parts at realistic levels without driving amps into serious clipping. Certainly when I had PMC EB1i speakers (89dB/W, 4 ohm nominal) driven by Bryston 4Bsst (capable of 500W into 4 ohms) I couldnât play with the average orchestral level at an unnaturally low 75dB level without pushing the amp into serious limiting on the canons. On paper the 350 with those speakers would allow about 5dB more, getting closer to realistic. That of course is an extreme example, but then there are other speakers that may be more challenging to drive than the EB1âŠ
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According to HiFi News, output of 500 doesnât double as impedance halves, and runs out of steam below 2 ohms (unsurprising for a bridged design): they quote 142W into 8 ohms, 228 into 4, 322 int 2 and348W into 1ohm.
Ignoring oddities like the 1ohm Apogee Scintilla, there are speakers that go as low as I ohm, with nominal impedances of 4 ohms if not higher (I do not know any specific examples, but that is what I have gathered over the decades).
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Interesting google on that recording.
Known as âthe speaker busterâ, with peaks for the canons at 8Hz. Ouch.
Yes, it is not a routine play of mine -in fact since changing my speakers a year ago I havenât tried it - this is a prompt for me to do so, especially as I now have an amp supposedly capable of 50A peak current which is equivalent to 2500W at 1 ohm (these speakers are also 4 ohm nominal - but also 2dB/W higher sensitivity, so on paper I might be able to play at 8-9 dB higher average level, which would be near enough realistic orchestral level - and canons might be approaching 120dB at the listening position (very loud, but not ear damaging). If I can play with the orchestra at proper level it would be more enjoyable, and I might play more often, though itâs not my favourite version.
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