The F4 is a jewel... and seems underestimated

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Yes sir. That's where I got my pair. I'm hoping someone else will try this out and give their impression. Early days but I think it sounds really nice.

There's a lot I don't understand about them...didn't you say you got 6dB more gain like this? In F6, I understand there is no gain from transformer, but from solid state bits, while in M2, solid state bits are buffer, and gain is from transformer.....yet your method gives 6dB more, right?

Anyone tried M2's edcore like this?

Russellc
 
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There's a lot I don't understand about them...didn't you say you got 6dB more gain like this? In F6, I understand there is no gain from transformer, but from solid state bits, while in M2, solid state bits are buffer, and gain is from transformer.....yet your method gives 6dB more, right?

Anyone tried M2's edcore like this?

Russellc

Yes, 6db gain per this diagram (stole from Zen Mod). Here's the spec sheet on the Jensen transformer if you need it: https://www.jensen-transformers.com/wp-content/uploads/2014/08/jt-123-flpch.pdf

It's important to drive this arrangement with a low output impedance circuit for the best possible result, hence the buffer you always see in front of them. Wayne's discrete op amp has a fraction of an Ohm.
 

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I'm liking the Burning OpAmp right now with my monoblock F4's. I have a Jensen autoformer between the two for some more gain. But there is something more to adding this signal iron than just gain. I'm not sure what it is, but I like it. Currently rebuilding my linestage to make it all more permanent. It's been just all tacked together for testing.

Now to see if I can de- solder transformer from F6 board. Maybe I should get new set ....I do have some edcors around, seems like someone tried them with a buffer here and wasn't so impressed?

Russellc
 
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I was able to remove mine without any drama. But slinging solder for nearly 30 years maybe helps a little..

About gain needed which is always part of F4 discussion.. I've found with my own situation, 18db in this linestage (12db SS bits, 6db iron) is almost spot on. I don't use any resistive attenuation at all. The digital attenuator in my DAC is not throwing away too much at my normal listening levels. I think gain structure is really important. Some of my old systems had "hair trigger" volume controls before I knew any better.
 
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