If there is no hum. The powersupply is good enough.
You must look at the grounding between source and preamp or preamp and housing. Better is no connection between input plug and chassis and/or connection between preamp ground and housing.
How looks the source/volumecontrol you use?
You must look at the grounding between source and preamp or preamp and housing. Better is no connection between input plug and chassis and/or connection between preamp ground and housing.
How looks the source/volumecontrol you use?
Hello, amazing project ! Thank you Koifarm !
Would anybody have a spare PCB to sell and send to France ?
Thanks !
Would anybody have a spare PCB to sell and send to France ?
Thanks !
Ordering yourself with the gerberfiles at jlcpcb with global shipping will cost you only a view euro for 5 pcb’s in a color at your choice.
Hello,
On the first post, it's sayd that the gain for the mu follower can be set to x3, x9 or x17. How can I do this ?
Thanks !
On the first post, it's sayd that the gain for the mu follower can be set to x3, x9 or x17. How can I do this ?
Thanks !
With the J1 dipswitch you can select the gain. For 1 channel switch 1 and 2 on is 3x gain. Switch 1 off and switch 2 on is 9x gain. Switch 2 off is 17x.
Build done !
Another question : would it be possible to use the mu follower circuit as a headphone amp by using the 17x gain and a pot for the volume? Many thanks
Another question : would it be possible to use the mu follower circuit as a headphone amp by using the 17x gain and a pot for the volume? Many thanks
Just try it. Use with low impedance headphone 47 ohm serie resistors.Use as less gain possible, then output impedance is as low as possible. Normally you need an extra buffer.
Works like a charm as a buffer between a dac and a solid state amp. Excellent job !
If I want to use it as a preamp so with a volume pot, what is the best value to use for the pot, and the best place to put it ?
Many thanks !
If I want to use it as a preamp so with a volume pot, what is the best value to use for the pot, and the best place to put it ?
Many thanks !
There has been lots of discussions about where to fit pots, mainly due to handling differing line level outputs from sources and minimising the loss of detail in the signal by reducing the level before it is amplified. I think the consensus was to add an attenuator to the input, if it is adjusting the line level that is the primary concern, and put the volume control on the output of the preamp, so it is the amplified signal that is controlled for loudness level. Searching for 'volume' and 'preamp' here should find the discussion.
100K log pot is the normal one one that is fitted, sometimes 50K (modern equipment) or 500K (old) depending on sources.
100K log pot is the normal one one that is fitted, sometimes 50K (modern equipment) or 500K (old) depending on sources.
Something like this, Remove R1/R11. Input impedance stays about 100k.
When not remove R1,R11 input impedance varies between 50k and 100k.