Thanks Nelson

[Zen Mod]

good to go

put 10-100uF from trimpot wiper to GND


of course , you can put smaller output cap , if going high pass

 

[marconi118]

And reduce the choke to 5mh or use a bulb...
Will try it and report on it here

 

[nzlowie]

Wow! With that sort of efficiency, you could get away with a 12V MoFo, maybe even battery powered. With a nice tube pre, Bob's your uncle.

Still looking and thinking about the next project.... The MoFo looks a cool project but I think it needs a pre with a large voltage output, correct?
I was hoping to use my DAC output to drive the amp as I'm currently doing. Or if I have to use a pre then I'd need something that could drive the MoFo and the Berhringer amp that I use for my bass section.

So would there be other good low power options that can be feed directly with line level from my DAC?

Thanks Dave

 

[Zen Mod]

lemme see ....... you wrote in post #1 , that 5W is magic figure

that's roughly 18Vpp

if we divide that with 2 then 1.41 , that's 6.36Vrms

so , any gain stage capable of 9db gain and 18Vpp output signal , will do the job , considering regular 2Vrms output of digital thingie

you can insert that gain stage in between active xover and follower amp , so no unneeded swing strain on xover circuit

 

[nzlowie]

lemme see ....... you wrote in post #1 , that 5W is magic figure


you can insert that gain stage in between active xover and follower amp , so no unneeded swing strain on xover circuit

Hi ZM , I don't use an active xover (waiting for the new B4) the DAC drives the power amps direct. The bass amp has DSP so that provides the low pass and I have a passive xover on the mid/hf amp.
What I've read about the MoFo (I may have it all wrong though...) tells me the DAC won't have enough drive to by itself. Maybe I've misinterpreted what's been written or haven't expressed my intention clearly enough, wouldn't be the first time for me. Just saying the my bass amp which is a power amp only doesn't need a pre amp but the MoFo will, if infact the DAC won't drive it directly.

Just trying to keep the signal chain to the bare minimum.

 

[Zen Mod]

whatever , what is important is that you got proper reply regarding MoFo - you need no more than 9db of gain , considering regular DAC output level

 

[Nelson Pass]

so , any gain stage capable of 9db gain and 18Vpp output signal , will do the job , considering regular 2Vrms output of digital thingie

Most of the time. A little more gain would be good, as there are some
recordings made with peaks well below 0 dB, Paul Simon for example.

 

[Zen Mod]

of course ....... I often forget to mention that - headroom is conditio sine qua non