Bobby Oswinski's Abbey Road Reverb technique.

• Add a plate reverb, pre-delay 55ms
• For the input to the reverb:
• Roll off low-end of reverb, say 600Hz at -12dB/oct
• Roll off top-end of reverb, say 6.5kHz (2kHz to 10kHz) at -12dB/oct -- maybe higher frequency in verse when less going on
• Cut mid at 1.2kHz, -2 or 3 dB (1.7Q)
• Add saturation, Warm Tube (Fab Filter Saturn!)