Versatile and comfortable passive pre-amp

[redjr]

It's Finished! 99% Anyway 🙂

It's been a long time coming, but I now can share some pics of my journey and finally finished RPre LDR volume and input switch control. I'm waiting on a new, re-programmed proc from Rudi, but other than that it's ready to go into service.
No significant listening yet, but I'm sure it will sound great! 🙂

Rick

 

[AndrewT]

Undo all those plaited signal input wires.

Use a twisted pair for EACH signal input.

 

[Rudi_Ratlos]

Andrew, I am not as strict as you this time.

The RCA-plug connects to a 3-pole PCB connector with Signal-Left, Signal-Right and "Common Signal-Return" pins.
You can of course crimp both Signal-Left-Return and Signal-Right-Return of the RCA-plug into the common PCB crimp contact, but since Rick twisted both signals with the "Common Signal-Return"
and since the wires are very short, his way to do it is quite o.k. in my eyes.

@Rick: you have done a very beautiful job, and I am sure that your ears will be delighted by the PRE's sound.
I will program 2 PICs for you this afternoon and send them to you tomorrow.

Enjoy listening - Rudi

 

[AndrewT]

since Rick twisted both signals with the "Common Signal-Return"

He does not show a pic of twisted pairs.
He shows a plaited 3wire

 

[redjr]

Andrew, I am not as strict as you this time.

The RCA-plug connects to a 3-pole PCB connector with Signal-Left, Signal-Right and "Common Signal-Return" pins.
You can of course crimp both Signal-Left-Return and Signal-Right-Return of the RCA-plug into the common PCB crimp contact, but since Rick twisted both signals with the "Common Signal-Return"
and since the wires are very short, his way to do it is quite o.k. in my eyes.

@Rick: you have done a very beautiful job, and I am sure that your ears will be delighted by the PRE's sound.
I will program 2 PICs for you this afternoon and send them to you tomorrow.

Enjoy listening - Rudi

Thanks Rudi,

It's my own fault it took so long. 🙂 I'm just too methodical! Anyway, I'm glad it all worked - short of the PIC bug. Hopefully, I'll get some time this weekend to listen to it. But, as I said earlier, it sounded very, very good during testing on my bench.

Rick

 

[niss_man]

Finally finished this great Pre. Thanks Rudi.

Finally had a need for my pre and so finished building the beast. Here are some pics of the beast. Timber is Camphor Laurel.
Thanks for making this happen Rudi. Are you going to offer boards like this again?

Cheers

Simon