Electric Trains - Whistles, Hooters or Horns?

[darwins]

What sort of warning device did the various LNER electric trains have?
Did they have a whistle, with a high note, similar that used by the LSWR/SR?
Did they have a hooter, like the ones on older London Underground trains such as 1938 stock?
Or did they have an air horn like one of the pair of modern two tone horns?

There may have been differences between train types also.
Original NER emus and locos.
LNER Tyneside emus.
MSJA emus.
Manchester area and London to Southend emus.

EM1 and EM2 electric locos, I beleive originally had an air horn. (single tone)

[Trestrol]

The Tyneside Electrics had whistles from new. They were later fitted with Horns in BR days. I would have thought the Shenfield and Manchester EMUs were the same and were converted later.