I have the 300b preamp and really like it, mostly use it for headphones these days. My main preamp is the Allnic L5000 DHT preamp, which is almost too wonderfully special to describe, but the Manley isn't chopped liver and is fantastic with headphones.
I use Svetlana 300b, entirely too sensuous sounding and not bad on price.
JJ 300b's are models of clarity and space with the Manley.
I have been using the Manley 300b with Stax Lambda headphone. I took a Stax transformer intended for speakers, the srd 5, and soldered the wires to a banana jack to plug into the Manley 300b headphone socket. The Manley has more than enough juice to give a magnificent headphone experience with the Stax.
I use Svetlana 300b, entirely too sensuous sounding and not bad on price.
JJ 300b's are models of clarity and space with the Manley.
I have been using the Manley 300b with Stax Lambda headphone. I took a Stax transformer intended for speakers, the srd 5, and soldered the wires to a banana jack to plug into the Manley 300b headphone socket. The Manley has more than enough juice to give a magnificent headphone experience with the Stax.