Universal PCB for Purifi 1ET400A amps

[_henry_]

found it, Toggle DIP switch

@Koifarm what switch do you use for the J3?

 

[_henry_]

@Koifarm

what's the use of the holes at XLR jack part aside from 1,2 and 3 pins?

Edit : never mind just realised this is for the nc6j fah with TRS

 

[Koifarm]

Henry, very good to amswer your own questions

 

[_henry_]

Henry, very good to amswer your own questions

@Koifarm Do you have psu design schematic if we want to use linear psu instead?

 

[Koifarm]

I have no schematic for a linear supply for this preamp. I think smps is the best option( no humm ).

But you can simple build the HV supply with 200V/min 120ma transformer, rectifier, elco,lr8n/tip50 combo to get 265V/ 60ma.
And for the heater supply a 8V/5a transformer,rectifier,elco,lm338 combo to get 6.3V/ 3.5A.

Just look on the WWW.

 

[_henry_]

I have no schematic for a linear supply for this preamp. I think smps is the best option( no humm ).

But you can simple build the HV supply with 200V/min 120ma transformer, rectifier, elco,lr8n/tip50 combo to get 265V/ 60ma.
And for the heater supply a 8V/5a transformer,rectifier,elco,lm338 combo to get 6.3V/ 3.5A.

Just look on the WWW.

Ok thanks 👍

 

[_henry_]

just got the PCB, very high quality PCB from JLCPCB.

abit tough inserting the 36pins socket , but managed to do it anyway. haha

 

[Carl_Huff]

Henry,

Well that was quick. I have been dragging along and haven't even ordered my PCBs yet. That is quite a color!

Please keep us posted as to your progress.

 

[_henry_]

Henry,

Well that was quick. I have been dragging along and haven't even ordered my PCBs yet. That is quite a color!

Please keep us posted as to your progress.

Will do!

 

[_henry_]

Progress

 

[Carl_Huff]

Henry,

It looks like you are coming right along with your project. How are you doing finding parts such as that B06P-VL (PCB Socket connector)? Power supply??

 

[_henry_]

Henry,

It looks like you are coming right along with your project. How are you doing finding parts such as that B06P-VL (PCB Socket connector)? Power supply??

The b06 still not available, will use wires and terminal blocks instead and will reassess if really needed the socket.

 

[jean-paul]

I have no schematic for a linear supply for this preamp. I think smps is the best option( no humm ).

But you can simple build the HV supply with 200V/min 120ma transformer, rectifier, elco,lr8n/tip50 combo to get 265V/ 60ma.
And for the heater supply a 8V/5a transformer,rectifier,elco,lm338 combo to get 6.3V/ 3.5A.

Just look on the WWW.

Some Schottky diodes, a large buffer cap, a LT1084/LD1084 and a 7V transformer will result in less energy lost in heat. With 3.5A just 1V difference is 3.5W less heat....

Builders will ask the same questions as DIYing a "simple" PSU from scratch really is a bridge too far for many and many will also not want SMPS for such a low power application. Some like PCB's/modular sections to be of similar appearance as a "set" too. As this is about ready made click and play modules combined with a now incomplete DIY frontend it would be nice to have a complete design for successful builds.

 

[Koifarm]

As stated a few replies before i use a smps for the tubebuffer. Easier for DIY is almost not possible.
Another bennefit from the smps for DIY designs is, less chance of humm.

 

[rubley00]

Can't help but wonder why?

I'm with you. Buy an expensive, super-low distortion amp module, and then feed it a low quality input signal. smh

 

[Koifarm]

To have a good base with the classd amp. And then you can fine tune for a sound you like more. It is like selecting loudspeakers. It is personal.

 

[cab]

To have a good base with the classd amp. And then you can fine tune for a sound you like more. It is like selecting loudspeakers. It is personal.

Why not just use dsp?

 

[Koifarm]

Witch DSP can adjust slew rate? And adjust harmonics? And do not ad digital artifacts? I have a lot of standalone DSP's from DBX, Behringer and PC plugins for cubase, But i like the complete analoge path the best. Just recordplayer, phono preamp, passive volume control and tubeamp. For daily use i accept listen to streamer, dsp, passive volume control, classd amp.

 

[cab]

Witch DSP can adjust slew rate? And adjust harmonics? And do not ad digital artifacts? I have a lot of standalone DSP's from DBX, Behringer and PC plugins for cubase, But i like the complete analoge path the best. Just recordplayer, phono preamp, passive volume control and tubeamp. For daily use i accept listen to streamer, dsp, passive volume control, classd amp.

Plenty of dsp plug-ins to add that tube distortion. Why worry about digital artifacts when you are already using a colored amp?

 

[Koifarm]

The unbuffered purifi amp has the less colouration I experienced until yet.

It is not only about adding distorsion. Also very important is the change of slewrate and frequentie depending fase shift.