Active NAP500 DR Upgrade
Posted by: Darke Bear on 13 August 2016
I recently got my set of three Nap500 re-capped and upgraded to DR two weeks ago. They were eight years old so I was going to get it done in the next year or two anyway, but hearing friends DR update performance-lift in passive systems I was suitably impressed and wondered how it would sound in Active use.
Last year I purchased the S1 Pre which was a large upgrade in performance from the 552 I had been using. Add to that the full loom of SL leads I got at the same time and I’ve experienced a large lift in musical performance already – I was wondering if I was being greedy, the answer is obviously yes! 
I’ll leave aside the painful run-in experiences, aside from that I really needed ten days warm-up to get from variable ‘HiFi’ sound to music-making. There is still run-in going on, which manifests as a meandering sinusoidal increase and decrease in performance over time, but it has settled enough to get some first impressions.
I’m very pleased and impressed with what the DR does. There is a lift in clarity and removal of ‘gaps’ in the resolution when music becomes complex or loud – it was as if before things gently smeared-out the resolution at transients. This is especially noticeable on drums and bass guitar notes when played fast. Now there is more power and definition on busy riffs that was not there before.
Overall the Amps produce a bigger and brighter picture of the performance – a larger window into the musical performance.
For example, on the old Renaissance ‘A Song for all Seasons’ which is a complex Prog-Rock with Orchestra, guitar, synth and Annie Haslam’s powerful soprano vocals the album becomes a live album! A friend who knows the Album well and my system, was convinced I’d swapped the CD for a live version – I had to extract the disk for his scrutiny before he admitted it was the same old CD. That particular CD (an old version) has large dynamic range and a lot going on that is now beautifully rendered with clearer insight into the performance and Artist-intent than I’ve heard before.
Overall the DR 500 resolves lower frequencies better and has lower distortion in the high frequencies. The LF does seem to have a lower roll-off point too – it is more seamless and fulsome in a good way. This matches what the S1 Pre did, as that also took the bass performance much lower with far better power and control. The combo CD555S (2x555PS)- S1 Pre – 3x500 DR with Ovator S800 works together beautifully as a system in my opinion.
The usual question is – ‘why don’t you go Passive S1 Monoblocks instead of Active 500DR?’
They are different systems in what they each do well and I prefer what I have done along the Active path.
I’d love the S1 Monoblocks as they are beautiful and in a different league to the NAP500 even with DR, but you still get the passive effect I don’t like – a gentle smothering of the dynamics and immediacy of the performance that is portrayed so much better Active. I can’t afford a set of four S1 Monoblocks - love to but can't.
Back to the DR 500: It is difficult to properly describe what I mean by grater ‘clarity’ - I'll try. The reproduced note-structure and power of both voice and instruments is as if they are playing inside your body at times – I’m not meaning playing loud, just more clarity and power in the harmonic structures with less smear.
And the system does go a lot louder with less dynamic ‘cloying’ at the edges – it is clean, clear and fulsome. One thing I like about a good Active system is the removal of dynamic effects of one part of the music treading on another – this is done much better now.
In short – if you are dithering about getting your NAP500 DR updated – get it done, funds permitting. 
My thanks to Naim for turning it all around in two weeks and my Dealer, Signals, for making it all happen.
DB.
Less distortion Energy = Cooler.
With an Active system distributing the load over three Amps and without any Passive crossover losses ... if you are running hot I would not want to be your neighbors. 
DB.
Darke Bear posted:Less distortion Energy = Cooler.
With an Active system distributing the load over three Amps and without any Passive crossover losses ... if you are running hot I would not want to be your neighbors.
DB.
just as well i decided to have my 500s DR'd and one of them serviced -- this must have reduced distortion significantly, evidently...
no problem with neighbours as my listening room doesnt share a common wall with them -- just as well since i sometimes play my system quite loud
enjoy
ken