I’m using the Denon Avr5800 as the preamp.

The Krell FPB600 required input 3.4V for its 600W rated power @ 8ohm.

The Denon AVR5800 pre-out rated output voltage is 1.2V so it only can drive the FPB600 up to 78W @ 8ohm.

Wow thanks for the info. Where did you get the stats at I was looking for it on the Denon 5800

The specs are easy to find, except the output voltage they don't usually show that spec on avr's.

I must get a great a preamp that can deliver more than the 3.4 volts it needs for the kKrell to deliver 600 watts into 8 ohms. Wow should get alot louder.

I’m using the Denon Avr5800 as the preamp. I dont know if I’m driving to full load but I have Denon cranked all way up 06 db

Some might think that if a digital source can output a voltage of 2V, crank the volume of the Denon all the way up to +6dB the pre-out should output a voltage of 4V, BUT THAT’S NOT ALWAYS THE CASE!

https://benchmarkmedia.com/blogs/application_notes/19947905-the-audio-path-in-consumer-grade-audio-products?_pos=1&_sid=1805d554a&_ss=r

I must get a great a preamp that can deliver more than the 3.4 volts it needs for the Krell to deliver 600 watts into 8 ohms.

👍