What is an echo chamber used for in recording studios?

I am reading a great book called Temples of Sound. It is about famous recording studios across america. I have one question about it though, what are these echo chambers that they talk about and what are they used for? Are they like a modern day reverb device? Does anyone have a picture of them?
Thanks!

I can’t find a picture, soorry. I’ve seen them, though.

Yes, in’s the very analog reverb. You have a concrete room with a speaker and a mike. From the miximg board the studio could send the signal from the musician to the speaker and pick up the signal plus echo with the mike.

A picture of the room would be pretty boring, as it’s just a room with a speaker and a mic.

Along with the echo rooms, recording studios also put speakers on large metal plates to create a reverb effect. Later, a speaker on a slinky type spring.

I love old tech recording gear, but I’m GLAD those days are over. I’ll take my rack mount reverbs any day of the week.

Festival Records in Sydney which is a world class facility used the ladies toilet as the echo chamber for vocals in the 1950’s. But I don’t have a picture.

From here. AFAIK, the chambers are still there, having survived the fire. I was watching E! one night and they took a camera down there; nothing really inhabitable.