An illustrated guide to building an F5

If you decide to use a pot alone, as a passive pre-amp, then that decision carries with it the acceptance that the pot output impedance needs lot's of skill and experience to get good performance from the system.

If you don't understand my previous statement then you should not be using a passive pot as a pre-amp.
 
Kofi,
Post 53 by Jumna in the thread preamp ideas for f5 is tiny simple and sounds good to my ears. I have a preamp that uses his circuit for a couple of inputs and uses a DCB1 for the others so I have choices.....
Evan

Juma not jumna

Thanks! This looks perfect.

Common, Kofi has people to look for him, he never learned how to do that himself.

Have you seen my keys?

Kofi

P.S. Seriously, I can't find my keys. Please help.
 
Thanks! This looks perfect.



Have you seen my keys?

Kofi

P.S. Seriously, I can't find my keys. Please help.

on the other hand. i just tonight maxed out my aleph P1.7 with 10db gain on my F5:) and was stil missing alot. damn those low level downloads:)

have to ad one thing. it was not close to cliping. even with a good level recording.

you will hear that a good CD player or DAC can put out 2V. yes it CAN. but the recording WILL hold back.
in the real world, you will see about 0.32V avrage.. or 0.5V if you are lucky. nothing near 2V rms.
 
Last edited:

6L6

Moderator
Joined 2010
Paid Member
Change R5 R6 R7 R8 to 150 or 220 ohm. You will get more gain, at the expense of a bit of feedback. I built one F5 stock, one with 150ohm resistors, and they sound identical, but the one with 150R is noticeably more sensitive. People who have build them with 220R report wonderful sound and the ability to clip it with a CD player.
 
I built a new board as the other was mangeled from being pulled in and out oft he enclosure. All the voltages seem to check out, however I am still unable to draw current through R11 &12. I am not sure what to do from here.....
 

Attachments

  • IMG_1063.JPG
    IMG_1063.JPG
    215.4 KB · Views: 792
  • IMG_1064.JPG
    IMG_1064.JPG
    209.6 KB · Views: 768
  • IMG_1065.JPG
    IMG_1065.JPG
    194.7 KB · Views: 757
  • IMG_1059.JPG
    IMG_1059.JPG
    282.1 KB · Views: 753
  • IMG_1050.JPG
    IMG_1050.JPG
    274.1 KB · Views: 758
  • IMG_1047.JPG
    IMG_1047.JPG
    247.2 KB · Views: 365
  • IMG_1046.JPG
    IMG_1046.JPG
    187.5 KB · Views: 330