My F4 Build

[Einric]

R9 is changed out for 5k and everything is perfect.
I have it biased at 150mV and I have 0mV offset.
I am waiting 30min for the temps to come up and then I will bias again and adjust offset.
My fans are going strong and I'm sure I won't hear it over .5W output power.

 

[Zen Mod]

 

[6L6]

I thought changing R9 would make everything behave. Awesome!

 

[Einric]

I am at 300mV bias now and I have 1mV of offset.
I will wait a bit to see where the temps normalize.

@ 200mV after 2 hours my middle pin temps were 38C

 

[Einric]

Ambient Temp: 23C
Bias: 300mV
Run Time: 3 Hours
Hottest Middle Pin Temp: 49C
Coolest Middle Pin Temp: 45C
Adjacent Heatsink Temp: 38C
Offset: .5mV
Rail Voltage: 22.4VDC
Secondary Voltage: 18.2VAC

I think all is well, after lunch I will have a listen.

 

[Einric]

ZERO turn on thump, DEAD QUIET!
Now I will fasten it up and put it in my main system.

 

[Einric]

Little Nicky got it wrong........
Pass DIY F4's are F***ING AWESOME!

I can't put it into words, but I do see some nice 12AX7's in my future, I need more gain in my Aikido.

 

[buzzforb]

ImPasse or BA3

 

[6L6]

Little Nicky got it wrong........
Pass DIY F4's are F***ING AWESOME!

Yep. It kinda ruins you.


In a good way.

 

[Einric]

I just disconnected my sub, I don't need it anymore.
Even if my F4 did peak 50W into my speakers it still wouldn't hurt them during movies.

My ear planted in the tweeter and I don't hear an ounce of the static I used to hear.
I'll pick up some matched JAN 12AX7's online.
I only want to run American tubes.

 

[Einric]

This is just insane, why do my 2 DA175's all of a sudden start shaking the floor?
I'm gobsmacked, why does A 25W do so much better than AB 120W?
The world may never know.

It's NUTS!

 

[wirewiggler]

could be they are looking at those bad@ss heat sinks and are shaken!

Bill

 

[6L6]

I'm gobsmacked, why does A 25W do so much better than AB 120W?
The world may never know.

It probably has something to do with the 400W PSU and the 220W of standing bias...

 

[Einric]

I totally know what 6L6 means, Loud doesn't even seem loud until you have something to compare it to.
This is totally a different experience.

 

[buzzforb]

Its not loud. It is body, depth, soul.

 

[Einric]

Now after 2 hours @ 300mV the heatsinks are still just barely warm to the touch.

 

[wirewiggler]

I have a pair of balanced F4s and a 500w Aussie amp and the F4s have more bass authority. Probably more to do with dampening factor.

Bill

 

[Einric]

Not only that but the bass is tighter and deeper at the same time, it almost defies logic.

 

[6L6]

Be it because of a logical reason or not, there is something truly special about the F4. I don't know what it is either, but I do know that I could stop building amps now and be happy with my sound.

(Not that I am going to stop building amps... I do that because the journey is it's own reward. But I would not be surprised if years from now, all the experience I will hopefully then have will just prove that the F4 is stupendously good.)

 

[Einric]

I'm already starting to come to that conclusion myself.

Now.......I wonder if the local Hi-Fi shop would let me hook my F4 to their Wilson Sasha's?
LOL, FAT CHANCE!
Maybe some of their Totems?