Cheap & Simple Streaming using my existing Naim Amps

If that's all you want do to why do you want a DAC?  I use Riffstation to create backing tracks and play along.  I just use a simple analogue lead from my iMac into my NAC552/NAP250 to play these while I mangle the lead guitar bit.  Easily adequate for the purpose, and much cheaper than a DAC.

Connecting a DAC to a spare analogue input on a pre-amp is generally straightforward. As discussed on other posts here, you could get up and running by buying an Apple Airport Express, and connecting that to the DAC with an optical cable. This will enable you to use Apple Airplay to play from any Airplay enabled source such as itunes, BBC iplayer, etc. from an iphone or ipad.

How this would work with non-Apple devices, I'm not sure, but I dare say there are ways.

This is a reasonably low-budget way to get up and running, easily built upon if you decide to move on from CD playing in the future.

Some DACs have decent headphone amps built in - I know a couple of guitarists who like to play along using headphones in this way.

I like this option, thanks.I could get an I Pad and Apple Airport Express.

To get me started are there any decent cheap DAC's that would do the job adequately for now. 
Also what cable would be needed to connect from my Naim PreAmp to the DAC ?

Thanks

the  HRT  music streamer reviewed in the latest issue of HIFI PLUS.  (116) looks like it might be what your looking for !

I'm no expert on what DAC to buy, I started out with a Spitfire DAC which was fine to get me up and running. They are available at every imaginable price point, from tens to thousands of pounds. Cables won't be a problem, any DAC will probably have standard RCA outputs. If in doubt, try Flashback Sales for reasonably priced cables, he understands Naim gear, and if you tell him what devices you've got he'll be able to supply a cable that will work.

The airport express is a good idea.....You would need a mini toslink to toslink cable to connect from AE to DAC.  You can get them online for a few bucks.  I am pretty sure the HRT DACs are USB only so I don't think that will work.  You need a DAC with optical.  Schitt I think makes some good inexpensive ones.  Can probably find used for under 100

From DAC to naim just check the naim web site for the PDF user manual download.  Probably some dual RCA to 5 pin DIN thing that naim uses that drives me INSANE !!

Sorry

Schiit    Not Schitt

The Airport Express has analogue outs, so there's no need to buy a DAC - just a lead with a 3.5mm jack on one end and whatever your naim has on the other. Very cheap way of getting going, allows you to dip a toe in the world of streaming too - and easy to add a DAC to later if you feel the need. 

Only thing to take into account would be latency - the streamed sound may be out of sync with any video on your iPad. 

+1 for the HRT iStreamer, if you decide to use an iPad.  I set one up for a friend, and it perfomed quite well into his Nait5i.  This was over a year ago, and it went between the 30 pin connector on the iPad into the RCA inputs on the 5i.  if your 122 lacks RCA inputs, you would need an adapter.  Also, i dont know if you will need to adapt lightning connector to 30 pin.  The iStreamer is porpose built to take digital output frm an Apple iDevice.

Of course there are many alternatives, but this worked well for us and is affordable.

Charlie

Audioquest firefly is also an awesome option.

As some others have written, you don't need a separate dac.  Just rely on the dac in the iPad (connecting it via its analog output (also known as the headphone jack) or over home wifi via an Airport Express and Airplay. (The Airport Express also has analog output.)

Ok brilliant,  so I guess I can either connect the I Pad Mini direct to the Naim PreAmp with a suitable cable using the analog headphone jack on the I Pad.  

Alternatively if I want to use wireless then I can get an Airport Express and connect from it's analog port to the Naim Pre Amp. 

In both instances what cable would I need ?

I'm not sure if your amp will accept a connection direct from the headphone output of an iPad, but it would be possible to connect the Airport Express directly to it using a cable with a 3.5mm mini jack at one end, and a DIN or RCA at the other, depending on what spare inputs you have on the pre-amp.

I didn't suggest this earlier as I thought, as a Naim owner, you'd find the sound quality unacceptable. But by all means try it - the cable will cost very little, and you can add a DAC later if and when you feel the urge.

Just one additional thought.  Your initial post said that you just wanted to use this link to play backing tracks for you to play along with on your bass.  I assume you mean an electric bass guitar?  If so, just check to see if your guitar amp has an MP3/Line input (my Blackstar does), and then all you need is a lead to run from your computer/tablet/ipad etc into that socket.  Not high quality sound, but adequate for the purpose.   I sometimes do it this way when I want to use some of my effects pedals (space restraints, SWMBO protests etc mean practising in a different room!  )

just buy a sonos connect far better than airport express £270 but it can be set to variety of channels on it's own wifi set up and its easy to set up 

software brilliant

can use spotify etc easy playlists.

it finds your music on your computer or network so you don't have to have a has or arse about with servers ump or whatever all that means

you can add a dac later if you want

beats airport express hands down - this tends to drop off is more limited and just a bit off a pig by comparison