Maximum DIY contents in the whole rig and never sounded this good….

[arunvenkats]

Next adventure and a daring one:

A balanced, chipless R2R through hole discrete and tube output stage DAC coming up.

View attachment 93500

This is amazing.

But even the best discrete resistors have 1% tolerance... and that spread across (I see 24 each side. 24bit?) 24 resistors. Are you planning to have any calibration and adjustment? But that would bring in digital electronics into it. Just wondering...

Brilliant project though! I always wondered how a truly discrete DAC would look like.

Regards,
Arun

 

[yogibear]

This is amazing.

But even the best discrete resistors have 1% tolerance... and that spread across (I see 24 each side. 24bit?) 24 resistors. Are you planning to have any calibration and adjustment? But that would bring in digital electronics into it. Just wondering...

Brilliant project though! I always wondered how a truly discrete DAC would look like.

Regards,
Arun

Arun,

Those are 0.1% through hole, matched resistors. Yes, it's a 24 bit DAC.

It's my final and most daring DIY attempt at a chipless R2R and there is more to it than the pictures show.

Since my DAC directly driven my tube amplifiers (two stage with onboard volume controls), the DAC balanced output will be converted to unbalanced through a pair of transformers. USB input is converted to I2S through a single converter. Power supply transformer is already wound and delivery is awaited.

So far I have built and tested chipless R2R, first with discrete opamp output stage (balanced) and second with output transformer coupled stage, again balanced.

This one is the third one with tube output stage and balanced output will be converted to unbalanced using a pair of trafos. So this one could be quite interesting and could prompt me to convert balanced output on two previous DACs into balanced using trafos.

Will update once the DAC gets fired up. Power supplies are meticulously crafted for lowest noise and excellent regulation.

 

[rupy]

View attachment 84880

View attachment 84881

Today my rig has maximum DIY content starting from the DAC, F2a Tube amp driven by BEL ECC88, Book Shelf speakers, and IC cables, speakers cables and it never sounded this good. Perfect clean, smooth sound….

(Last 10 years of non stop DIY finally pays…)

Looks super DIY

 

[arunvenkats]

Arun,

Those are 0.1% through hole, matched resistors. Yes, it's a 24 bit DAC.

It's my final and most daring DIY attempt at a chipless R2R and there is more to it than the pictures show.

Since my DAC directly driven my tube amplifiers (two stage with onboard volume controls), the DAC balanced output will be converted to unbalanced through a pair of transformers. USB input is converted to I2S through a single converter. Power supply transformer is already wound and delivery is awaited.

So far I have built and tested chipless R2R, first with discrete opamp output stage (balanced) and second with output transformer coupled stage, again balanced.

This one is the third one with tube output stage and balanced output will be converted to unbalanced using a pair of trafos. So this one could be quite interesting and could prompt me to convert balanced output on two previous DACs into balanced using trafos.

Will update once the DAC gets fired up. Power supplies are meticulously crafted for lowest noise and excellent regulation.

Awesome! please keep the thread posted about the progress.

Regards,
Arun

 

[yogibear]

EL84 IT coupled PP amplifier, no feedback, 10 wpc, finally sings. Very musical presentation. 6AH4GT at driver stage.

 

[yogibear]

Next adventure:

The discrete, through hole chipless R2R DAC with balanced tube output stage gets completed and sings with dark background and so far unheard musicality and tonality.



Next step is conversion of balanced to unbalanced (RCA) signal output using a set of custom wound transformers using a special core material.

 

[yogibear]

Quest for true happiness DIY way is an unending journey and small changes / tricks may surprise you. I attempted a few:

1. Substituted copper wire chokes with Mundorf copper foil ones in the speaker passive crossovers.
2. Used a high quality choke filter in tube buffer B plus power supply.
3. Used a USB to Optical converter by ECdesigns with their custom optical cable and an external 5V powered converter for optical to I2S for final DAC input.

The upgrade in sonics was significant with vocals taking a smoother texture, more resolution and distinct silvery HF extension. Now bells sound even more natural.

Next set of upgrades will involve conversion of XLR to RCA output signal on DAC through a custom wound iron and copper foil capacitors will replace MKP in passive crossovers.

 

[yogibear]

Next adventure:

A decade old wish comes true. RS1003 SE Amplifier crafted and plays glorious and huge !

 

[rupy]

View attachment 84880

View attachment 84881

Today my rig has maximum DIY content starting from the DAC, F2a Tube amp driven by BEL ECC88, Book Shelf speakers, and IC cables, speakers cables and it never sounded this good. Perfect clean, smooth sound….

(Last 10 years of non stop DIY finally pays…)

Kudos.I can feel the tremendous satisfaction.