Memory requirement

[cliveb]

I'm thinking of building a new Myth system on a RPi4 to replace an old Acer Revo 3700 that's been working nicely for years.
The plan is to run a master backend and a frontend on a single Pi4 using an external USB3 hard disk for recordings.
All I'll be doing is recording and playing DVB-T and DVB-T2 broadcasts (UK Freeview). Not interested in any post-recording jobs such as advert detection and the like.

Is the 4GB Pi4 enough for this, or would I need the 8GB model?
My existing Revo 3700 works just fine and has only 2GB RAM, although this only does SD - I'm intending the new one to also record & playback HD.

[jfabernathy]

I've built a FE/BE combo on a RPI 4 4GB. It can record 4 HD programs from a Hdhomerun at once, while playing an HD program that's previously recorded.

[cliveb]

I've built a FE/BE combo on a RPI 4 4GB. It can record 4 HD programs from a Hdhomerun at once, while playing an HD program that's previously recorded.

Thanks, that's good to know. I'll get the 4GB version.