SU/NAP180 biamp Majik Isobariks - upgrade power amp olive 250 vs 250.2/DR?

Posted by: JedT on 18 July 2017

I'm basically happy with how the system sounds - not looking for a major rethink - but my NAP 180 needs a recap and I'm tempted to buy a newly serviced olive 250 or a 250.2 with a few years before a recap (and perhaps DR upgrade) instead.

What is on my mind is that the MIsos are not short of punchy bass (!) but are if anything a tad too polite at the top end. I wanted this bias because my listening room has lots of windows and hard surfaces and forward systems can get a bit wearing.

My thought is that the olive 250 might actually be a better fit, the modern amps being a shade richer and smoother might reinforce the colour of the speakers more than is ideal.

Would welcome any opinions.

Posted on: 18 July 2017 by ChrisSU

I would consider trading in the SU for a 272, and maybe upgrading the power amp at a later date.

Posted on: 18 July 2017 by JedT

Like I said - I'm not looking to go that far. The speakers respond to biamping so it is quite likely that a 272 would not improve matters until I could buy two new power amps and I'd still need to recap the 180. And I'm quite keen to keep the box count down - been there done that. hence my focused question on the differences between the power amp options.

Posted on: 18 July 2017 by ChrisSU

Fair enough, I'm just surmising that a 272/250DR might be a good low box count endgame to consider vs SU/250 biamped. A question best answered by yourself using a dealer demo. 

Posted on: 18 July 2017 by JedT

Yeah - the thought had occurred to me before but then you get tempted by a PSU upgrade on the 272 and soon you are talking a CHUNK more money. And an extra box. 

My dealer isn't going to be able to help with an olive 250 demo. Hence my question really.

Path of least resistance is probably to buy a 2nd hand olive 250 and give it a serious listen at home. If it doesn't work for me, I wouldn't lose much on resale. One of the conclusions I've reached over the years is that the interaction with your listening room is REALLY important and often trumps theoretical hierarchies (not least because speaker matching to room is important).

Posted on: 18 July 2017 by The Dude

...I own an olive 250 just returned from Naim following a service and use it with a 272 and this is a lovely combo...

Posted on: 21 July 2017 by JedT

Just picked up a recently serviced olive 250 and was listening to it last night (driving the bass units only). First impressions were somewhat cleaner, drier bass than the warmer, softer 180 (which was due a recap). As ever changes to bass presentation meant that I heard differences in the high frequencies too (a tad more detail, airiness). Promising

Quite how much of this was 250 vs 180 or recapped vs not-recapped or run in vs not run-in I don't yet know!

I will play around with putting the 250 on the high/mid drivers and then just using the SU as a preamp in due course.

I struggle to work out what SHOULD be the best combination:

a) isobarik bass units are quite power hungry - 250 might have biggest benefit there (perhaps because bass transients might effect the power supply to the more sensitive DAC/preamp electronics if the SU was driving them?) but...

b) I'm generally sympathetic to the idea that optimising high/mod frequencies is really important even to bass presentation (leading edge harmonics etc) and that putting the better amp there makes sense...

c) Yet if the 250 is so punchy and solid that it can muscle the whole speakers then switching off the SU power amp should clean up the supply to the DAC/preamp...  

I can see quite a lot of fiddling coming on.

 

Of course  in the case of c swapping the SU for a 272 starts to become a debate