July 3, 2024

TDA1541A-S1 DAC & Pass D1 Analog Stages

Once again, I like to have another DAC using TDA1541, because all of my previous built TDA1541 DAC already sold like hot cakes.

Same story, I missed it.

Because any DAC using TDA1541 has the magic that always keep me back again, to experience the sound quality from this marvellous DAC IC.

Today DAC build is completely different. I start with multiple power supply for each ICs voltage required, total of them are 5 individual voltages using a toroidal transformer and an EI transformer. Then going to rectifier and filtered using capacitors-resistor-capacitors to passively reduce the voltage ripples. The 10 pieces voltage regulators are used to every voltage required by every ICs pin. The signal from digital receiver to DAC IC are asynchronous re-clocking using external thermal-controlled-oscillator, then the DAC current output is converted to voltage by Pass D1 original design.

The result from this design are marvellous.


It is all staring with this schematic.

A standard connection to make DAC using TDA1541 and CS8412 digital receiver. The improvement are mostly on the power supply section as I describe above.


Then for the analog stages are copy from the original Pass D1 DAC schematic.

This analog stages is for the current-to-voltage converter, not using typical op-amps, but using FET IRF610 per channel and a buffer output.

The schematic is like this.


Since the Pass D1 analog stages circuitry are not complicated, so I start with this section first.



Then, I continue to the power supply regulators and supporting components for TDA1541 and CS8412 ICs.

All components are in the same board.





It doesn't take so much time to finished this section. Then, the next steps is put the asynchronous re-clocking circuitry.

This is new for me and I loved to see how this re-clocking will improve the sound quality.



The next steps are the primary power supply circuitry consist of 4 individual supply lines from a toroidal transformer.

This power supply section are for supplying the D1 analog stages and DAC circuitry. I use a lot of capacitors to reduce the voltage ripple.



Then I continue to the fifth power supply dedicated to -15 volt TDA1541 DAC IC.

Based on my experienced, this power supply section needs to separate with others. This to improve the stability of the DAC IC itself.



Then, I continue this building process by making the connection between the power supply board to DAC board.



Then I check all connection before putting all components inside the chassis.









The last steps are put the TDA1541 and CS8412 ICs into the socket board.

Even without asynchronous re-clocking components, this DAC should be working right away.


I still waiting the main part for the asynchronous re-clocker, is the 11.2894 MHz thermal-controlled-oscillator to come. Estimated on next month.

But I still can test this DAC on my audio system already, which sound very good.

I am impressed.

I doesn't have any clues to the improvement if I put the asynchronous re-clocker components next.

Disclaimer: Any statement and photos in this article are not allowed to copy or publish without written permission from the writer. Any injury or loss from following tips in this article is not under writer responsibility.

1 comment: