I’m a size or two down, 804D3 driven by 250DR and love the combo (have always liked Naim B&W combo), prior to that was N805S by 200 - no issues just wanted MORE, and had the spare funds to allow hence the upgrade, room is 22’ by 14’ relatively low ceiling…each to their own!
Was fortunate to have local dealer and home demo though and for that expense I would say a listen (in whatever environment allows) would be a must no?
Good luck in your search
I think there must be something seriously wrong with any speakers that can’t be driven comfortably by Nap500…
I can’t help directly on 800s, as I am another with 804 D3s. They work very well with an olive 250, ever better with 300DR.
As someone who disliked the B&W tweeter on particular for many years, I find D3 and D4 significantly better - smooth, sweet and airy when appropriate and no beaming (if you see what I mean) from the tweeter.
I have also heard 802s work well with a 250DR, but have not heard it driving 800s.
Can you hear these speakers at whoever is offering them ex-dem?
I can demo but if it’s a non starter I’d rather avoid the cost and hassle.
It’s really not a non-starter imho…
I’m sure I will end up with 300dr at some stage in the future and would not want to have to change the speakers again.
NAP500 is not a particularly powerful amplifier in the grand scheme of things, though it is sufficiently powerful to drive, probably, the majority of speakers. It might be pitched as upper-mid in terms of power delivery but there are a gamut of speakers which, for one reason or another, have been designed with impedance curves that require a higher power amplifier. There are also a gamut of higher power amplifiers on the market. It doesn’t mean there is anything wrong with the speakers for being demanding or with the NAP500 for being unable to drive them, they are just incompatible designs. At that juncture one is left with 3 choices; live with the incompatibility, change the speakers or change the amplifier. If you want to stay with Naim amplification, Statement is next in line.
Don’t think the statement or 500 is in my price range.
From the graph it doesn’t look like it’s dropping well below 4 ohms so why are they considered power hungry?
Someone better at interpreting these curves that I am can provide more detail, but I see they are below 4ohms from about 60 to 800Hz - thats not a dip, thats prolonged operation well below 4ohms, from upper bass to mid-mid range mid range. The speakers will spend a lot of time operating here and if you want to let the speakers really show their capabilities, this isn’t the easiest of loads. If they will be at low volume, for example in a small room, they might be fine - that would fall into my live with the incompatibility (compromise) category, which is a perfectly valid option.
Citing from Stereophile:
There are minima of 3.15 ohms at 91Hz, 3.1 ohms at 620Hz, and 3.67 ohms at 21kHz. Given that there are current-hungry combinations of 4 ohms and –52° electrical phase angle at 62Hz and 5.3 ohms and –39° phase angle at 8.6kHz, I believe this speaker should be rated as a 4 ohm load rather than the specified 8 ohms.
And now from Naim website:
The NAP 250 is stable into any load and able to drive a 2-Ohm load for long periods of time.
It means very little to me but it sounds like 250 is stable at 2 ohm and the speakers don’t drop below 3.1.
Personally, there are a number of speakers that 500 could not handle but actually fabulous. For example, Kharam Enigma series or even some models from Exquisite series, all models above Sasha DAW from Wilson audio.
The same is published for NAP300 and NAP500, but they manage difficult loads with different levels of (audible) ease.
I have only a basic understanding of impedance/phase graph interpretation but low impedance means the amp has to work harder as it draws more current which in turn generates more heat. If you need enough power to play at higher (subjective) volumes and get the most out of these speakers, you might find the limits of the amp. I don’t think 250 has fans (like the 300 and 500) so it will protect itself with a thermal cut out. You may never have a problem at low volumes but thats a lot of speaker for background music… 
I have probably reached my limit in terms of my own knowledge of the subject, there are others far more knowledgeable than I. Perhaps @Xanthe might chip in…
And they are huge. And you’re supposed to put them a good distance from any walls. Saw them at the shop in their demo room side by side with their smaller siblings.
(804d3 is actually kind of sleek in my view, beyond that model they get increasingly bulky.)
Whenever my NAP 250DR gets warm listening to classic rock, connected to 4 ohm NEAT Petite 30 I think the amp is about to blow up ! Only have the 250 at nine o clock max for short periods so probably an overreaction
Have a look at What HiFi’s review of the 800 D3s, where they conclude it’s really a 4 or 6ohmer and is current hungry if you want to play with any meaningful volume – they suggest min 100wpc amps (assume at 8ohm, which a NAP250DR isn’t really).
Have a look here (if not already) re another member who was/is running a set of B&Ws bi-amped with a 250 on the LF units.
Fried 250DR? - Hi-Fi Corner - Naim Audio - Community
The thing is with amps:
a- you really need to over-spec your amp to a speaker
b- B&Ws 800s are generally current hungry, which means that they’re ok at low volumes and probably with light-bass music (e.g. some blues and vocals) but ask them to play a digitally recorded bass-heavy track with volume and the impedance of ~3ohms will come to play, with the accompanying current demand (as the speaker is demanding more current control from the amp).
Personally, I wouldn’t hook up a NAP250DR to the 800s, as I think you’ll be only scratching the surface of what the speakers can do UNLESS you see them as a end speaker and are prepared to spend lots on an amp(s) to get the best out of them — and a single NAP500DR might just about suffice but they may need even more power to be honest.
OK, a little about amps and speaker loads.
Ohms law is well known:
Rearranged for current I = V / R
(And power = I^2 R)
So far so good,
However speakers are reactive loads not just simple resistances, and there’s the rub
With a reactive load, at AC, the voltage and current aren’t always ‘in phase’ some times the current lags behind the voltage, sometimes the current leads the voltage; it’s easy to understand the waveforms. What’s not so easy to understand is why and the maths that underlies this. This arises because of an effect that is mathematically an additional current flowing in a different mathematical dimension. The current in this mathematical dimension doesn’t add any power to the output, and so is termed the ‘imaginary dimension’ and the ‘imaginary current’. This imaginary dimension is at 90 degrees to the real dimension (the voltage and current that produce the output power), but there is a very real vector addition of the two dimensions. So, whilst for the load (and hence the usable power) it IS imaginary, the output transistors need to provide it in a very real sense, so they are subject to the current demand and power demand needed for BOTH mathematical components.
Hopefully you’ve followed me this far…
TL;DR:
If the phase angle of a speaker is a 45°, half the current goes into the ‘real’ current (and contributes to the power driving the speaker), half the current goes into the ‘imaginary’ current (which doesn’t increase the power driving the speaker). The output transistors have to provide both components of the current, so they see the sum of the current demand in both the real and imaginary dimensions.
So at any given frequency, not only does low impedance increase the current demand on an amp, so does a high phase angle.
Look at 70Hz:
~3.7Ω @ 45°
So for 100w drive to the speaker, requires 5.2A for the real current and another 5.2A for the imaginary current.
In other words as far as the amp is concerned it needs to supply 10.4A: current equivalent to driving a 1.85Ω resistive load… that’s a HARD load to drive.
I recollect seeing a picture of the speaker development room at B&Ws Worthing factory from many years back and they had materially sized current-pumping mono-blocks i.e. far more powerful than the then NAP500.
As I understand things their current/latter ranges have improved as regards reducing their hunger for current but they are still very ‘thirsty’ !
This thread may be worth a view:
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