headphones for tube system

Hi Audiogoners, greetings from the UK – I have a question that I hope someone will be able to answer for me.

Background: a lifelong music lover – (mostly contemporary ) and hifi enthusiast (albeit in a small way)  - now in my dotage and sadly with deteriorating hearing.

My system is an Abbingdon CD77, pre is a Melody 1688 II into a McIntosh 275 mk 4, B & W CM10 ser 2 speakers. Van den Hul cabling.

I want be able to use headphones and am not sure how to go about adding in an amp for them. Any suggestions and headphone recommends would be appreciated

It may not be ideal but since it appears your pre-amp has neither a 'tape output' or a 'pass thru' you will need to get a headphone amp and connect it to the low gain output. The downside is that you will be stacking volume controls. I don't know of a headphone amp with out a volume control off hand, but you should research this - if one exists this could be ideal for you.
Thank you newbee - I'll certainly check that. As you note; most headphone amps have volume control.
Just unplug your CD player from the system, if it's not too complicated, and connect a headphone amp when you want to use it.  If your CD77 is out in the open it should be easy.  If the wires are buried, I give up.  
As to suggestions for headphones, you just have to listen.  I have the Grado GS1000, which are very open sounding, but totally not isolated.  You hear everything in the room, so you need quiet.  I tried some closed back phones, but they sound too closed-in for me, compared to the Grado.  You really need to check it out yourself.  Personally, I hate headphones for serious listening enjoyment.  Fine for Ipads and stuff, but, for me, not enjoyable at all.