I remember that I've said to my reader: 'treat this blog as entertainment only', but somehow I fully understand that most of you want to start your own build electronic, especially building a vintage multibit DAC for their home audio, competing with (maybe) their currently delta-sigma DAC. This to proof about the vintage multibit DAC will outperform delta sigma DAC easily in term of musicality.
My initial suggestion for the starter in DIY audio is to build a DAC with TDA1543 here. This might be a simple build for an experienced builder, but for the beginner, it is completely a ground-up and takes so much time and effort.
It is not easy either and I am fully understand.
So, I start thinking the easiest way to do this build is by finding a cheap vintage multibit DAC from the car audio product that came from that era. I found one candidate that completely suitable, it is the affordable Nakamichi DAC-41.
Let's start build a DAC!
Nakamichi DAC-41 is car audio component DAC that came after their top-of-the-line DAC product, the DAC-101 You can imagine in the early 90s, the car audio already implementing CD transport separate with the DAC unit, just like home Hi-fi.
While both are multibit DAC, but their internal components are completely different. Nakamichi DAC-41 is a simple in design, more about cost constrain DAC that came in small form factor. It is just like a downgrade from the DAC-101 that more superior than this one. But it came with more affordable price and easy to get this product now.
The DAC-41 internal is equipped with the latest technology of resistor ladder DAC, 2x PCM1702 from Burr-brown. This is top-tier vintage resistor ladder 20-bit DAC in 90's before PCM1704 came after it.
I got this Nakamichi DAC-41 in September 2026 for just about US$50. Pretty cheap to start building a simple DAC.
Checking the input/output of this DAC, there are 2 digital input, both are coaxial SPDIF gold plated RCA input. The primary digital input is connect to the input-1, while the input-2 is automatically selected if the second digital signal feed to the input-2 simultaneously. For single digital source input, just stick to input-1 instead.
The audio output is two pair of stereo output via gold plated RCA connector. The idea is you can have multiple output to run multi-way amplifier and speakers system. Since they are actually just a stereo output and divide by 1K ohm resistors, I can suggest you to connect with a pair of them only, doesn't matters which output, they are basically the same. The reason for this is the current output from this DAC analog is limited, it cannot drive the next stage properly if connecting to multiple amplifier.
Powering up this DAC is by using 12 volt power adaptor, minimal 1 ampere, better the low-noise type SMPS power supply for audio video equipment. This power adaptor mostly use DC plug type that has positive in the center and negative at the outer. Better to have the internal short-circuit protection to avoid any error while put the DC into this DAC, which this is more important for safety reason.
To connecting this DAC is just simply connect both yellow and blue cable together and goes to positive supply. For the black cable goes to negative supply. The power adaptor connector is using the female DC socket and connect to the SMPS power adaptor seamlessly.
If the polarity is correct, which I strongly suggest you to double check with volt-meter DC about the voltage output and polarity from the SMPS power supply before connecting it to the DAC unit, it will turn on this DAC.
Funny things, there is no LED indicator to show this DAC is power ON. So the only way to make sure it is operate is by connect this DAC directly to the audio system.
Somehow if the DC plug is reverse, you also no need to worry. There is a chance that the fuse in-line with the yellow power cable will blown, or if your SMPS power adaptor has internal short-circuit protection, it will shut the DC output automatically.
Well, as you can see this internal Nakamichi DAC-41 is consist of dual 20-bit PCM1702 multibit DAC. The digital input is goes to logic ICs for the input selection (as I describe above) and digital buffer before goes to YM3623 digital receiver. Although I am not a fan with this IC because of its very limited digital output option and high jitter, but I really understand that in that era, not many option available for the manufacture to choose.
The next stage is oversampling section SM5841CP which also a standard quality oversampling IC that I wish I could have the better option such as SM5813APT.
The analog section is simple LPF section and buffer with an op-amp per channel. The op-amp is dual channel, low current type NJM4572. This op-amp do well for its job, but not the best since the current is main issue in this DAC.
Then the internal power supply section is the main flaw. This DAC not use switching DC-DC converter circuit that most high performance car audio component implement it, instead it use simple virtual ground and voltage splitter. This virtual ground with op-amp and bipolar transistors as current amplifier cannot goes high current because of this design. That is why all the components use in this DAC is limited with low-current power ICs.
Thankfully there is one things that I can do for this DAC sound improvement, it just adding a film capacitor, about 100nF in the blank location of C514L and C514R. I think this location is prepared by the designer for the sound improvement over the electrolytic capacitor, as the DC coupling at the signal output.
Besides that, I just remove the digital input-2 RCA socket and replace it with female DC socket directly to the case. It look clean and just like a home DAC unit.
After careful checking few op-amps datasheet, I can replace the op-amps in this Nakamichi DAC-41 with similar low current type is OPA2134. This will improve the sound quality because of the better performance of this op-amp, but with slightly higher current rating from the NJM4572.
For now, I will keep this DAC as is. For the op-amp upgrade might be done later.
Nakamichi DAC-41 has many internal flaw caused by the power supply design. It can be much improve if it use dedicated power supply that serve higher in the current and voltage, especially to the op-amps in the analog section.
Without major upgrade, in this DAC condition, it surprisingly sound good and enjoyable. The natural sound and detail of the music presenting quite well, with fluid and depth as multibit DAC sound signature is.
This is not bad for the first DAC project at all.
Maybe later on, when your skill getting improve, the next step is upgrade the power supply section and analog stage.
Cheers!
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.
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