I have experience with passive line stages. Basically it’s just a volume control. My first was using the digital volume control in my dac back in the 90’s. I’ve also used extensively resistor and transformer based. Including two from Bent audio and a Placette. Most SET amps are easy to drive and work fine this way. Some push pull, but not usually as easy.
I wouldn’t agree that an active preamp is a waste of money. For the price a passive is a good choice. But in my much experience a quality active preamp will give much more performance than a passive. My experience was comparing to my Atma-sphere Mp1 years ago. Many times more costly too. There’s more to an active preamp than gain. Usually your source is putting out more gain than you need. If your listening just for detail and lack of distortion, a passive is hard to beat though.
I wouldn’t agree that an active preamp is a waste of money. For the price a passive is a good choice. But in my much experience a quality active preamp will give much more performance than a passive. My experience was comparing to my Atma-sphere Mp1 years ago. Many times more costly too. There’s more to an active preamp than gain. Usually your source is putting out more gain than you need. If your listening just for detail and lack of distortion, a passive is hard to beat though.