Naim 250PRO - inside look at an ultra rare Naim product

For the curious, this is a rare Naim product developed with collaboration between Naim and the BBC. It’s one of three delivered to the BBC. It’s based on a NAP 250-2 amp, and for studio purposes it has a balanced XLR input for each channel, and “Speak-On” output connectors instead of Banana sockets. Having recently restored one, here are some pics I took:

Amp boards removed and chassis cleaned

Two pairs of power supply reservoir caps removed

Amp Board ready for rebuild

Rebuilt Amp boards & balanced circuitry

Reassembly of Chassis

Completed Chassis

Front Panel

Rear panel (with new XLR and Speak-On sockets)

Definitely a unique project!

Chris - AV Options

26 Likes

Thanks a lot Chris, that’s fascinating.

I would like to have it . My preamp is balanced and have xlr outputs. Sad that Naim doesn’t produce it anymore.

I spy with my little eye output inductors! Presumably the BBC wanted to be able use any standard speaker cable without restriction.

except it seems it be a US voltage version.

Yes it’s 120V … the owner moved to the US and had it converted

The amp had to be stable no matter what kind of speaker cabling was attached to it.

Thanks for the pics Chris!

1 Like

Thanks Chris that was really interesting. I would be interested in in other pics of some of the older amps, players etc if you have the time.

@ChrisW

Which power cable is that ?

Hope this isn’t a daft question since I know nothing about studios, but what would its role have been exactly?

2 Likes

Hi Chris,

Thanks for the pictures.

Out of interest …how does it sound?

M

1 Like

Out of interest :+1::laughing:

Most likely for driving monitors in a control room or editing suite. LS3/5 possibly?

1 Like

I wonder as to how it sounds compared to a “regular” 250…

I once asked this of Roy. IIRC he answered that it sounded really good. Just not quite as good as the regular NAP250…

3 Likes

This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.