Hifi Forum TDA-1541A DAC Review

[Veri]

Same DIY design reviewed by @WolfX-700

Measurements of Hifidiy forum Anniversary TDA-1541 My DIY Replica

In 2014, the hifidiy.net forum released a series of DIY projects to mark the tenth anniversary of the forum. This 1541 PCB is based on the 1541 DAC project. Basically the TDA1315H input, SAA7220+TDA1541 architecture supports RCA and XLR outputs. Some of the above PCB replicas were made last...

www.audiosciencereview.com

Multitone is really good considering the age/era. Philips made good stuff.

 

[capslock]

Thanks for reviewing. I didn't even know there were fake 1541As around. Looked like too much trouble to emulate its design behavior, what with the strange on board oscillator for the dynamic element matching.

The harmonic performance is impressive. Makes one wonder what the silver crown and double crown chips did better. Maybe not even better harmonic performance but less noise. Even at this level, I would say noise is insignificant if one doesn't intend to use digital attenuation.

 

[MCH]

I find fascinating the R&D work of companies like Philips back in the day. Not only what they did but the seeds they planted somehow in so many fields.

 

[wwenze]

Curious, did the owner also have to change a bunch of resistor values and stuff? Because the TDA1543 DAC I own had values that would not work with a real TDA1543

 

[Limopard]

For nostalgic reasons (my first CDP 30 years ago featured the low cost variant TDA 1543 and didn't sound bad for DEM 250) I voted "not terrible". Otherwise it would be "poor". In 1991 it would have received a "fine".

 

[capslock]

Interestingly, after that, Phillips released lots of low cost DACs that had really poor performance (THD+N in the -70 dB) range, some of which still have an inexplicable following in diyaudio circles.

 

[Veri]

Curious, did the owner also have to change a bunch of resistor values and stuff? Because the TDA1543 DAC I own had values that would not work with a real TDA1543

No, this board fully supports a "normal" TDA1541A.

 

[DSJR]

I remember an engineer at Arcam telling me at the time the main contributer to the 'sound quality' of these dac chips was almost certainly in the digital filter these machines used as standard and NOT the 1541A (I was asking about the 'Crown' version which apparently had better low level linearity). Any 'more muscular' sonics I always put down to the analogue output stage used (there used to be a 'beefy, slightly dirty' quality to this generation I subjectively remember). I also remember sub 100khz noise coming out of such players which reviewer Paul Miller used to measure for I remember.

I'd also add that the noise output may play a subliminal role as well as 'we' really do seem to like this aspect, even if it's as low as this one is.

My Micro Seiki CD player is from this era (Marantz CD94/Philips CD960 chassis) but the output stage recommended to be used is an add-on with transformer coupled balanced outs. No doubt the 'sound quality' benefit this player had over its competition back then (late 80's) is actually distortion... Gawd this machine is complex compared to a modern better performing dac...

Donor chassis CD94 below. TDA 1541 can be seen with the green film caps surrounding it as my machine has under the copper cladding...

 

[McFly]

Same DIY design reviewed by @WolfX-700

Measurements of Hifidiy forum Anniversary TDA-1541 My DIY Replica

In 2014, the hifidiy.net forum released a series of DIY projects to mark the tenth anniversary of the forum. This 1541 PCB is based on the 1541 DAC project. Basically the TDA1315H input, SAA7220+TDA1541 architecture supports RCA and XLR outputs. Some of the above PCB replicas were made last...

www.audiosciencereview.com

Interesting, he gets 5V output there and @amirm gets 2.5 (max)

 

[bunkbail]

Interesting, he gets 5V output there and @amirm gets 2.5 (max)

Yeah dunno what's up with that since the boards are the exact same (Hifidiy.net design).

 

[McFly]

Ah, I see a few posts down wolf shows a picture of his board and there are XLR connectors added on, that would explain it. Double voltage.

 

[ousi]

Surprising to see an ancient (pretty much one of the first stereo 16bit 44.1kHz DAC chip; The Sony chip in the first CD player was mono actually) to perform better than some of the "boutique" DACs with tube output stage, R2R design and what not. Reaching 90dB in 1984 is not shabby at all, when you look at vinyls reaching 75dB only.

 

[capslock]

I remember an engineer at Arcam telling me at the time the main contributer to the 'sound quality' of these dac chips was almost certainly in the digital filter these machines used as standard and NOT the 1541A (I was asking about the 'Crown' version which apparently had better low level linearity).

Did he mean the mathematical quality of the filter or its digital switching noise? It was the equivalent of 74HC logic, so lots of ground and supply noise and quite a bit of ringing on the clock and data outputs. One did well to try to keep the supply noise local and use 330 R resistors and small caps to filter out the ringing.

Thanks for reminding me about the bit about better low level linearity. Yes, that was claimed by Philips, but with results like here or in Wolf's test, low level linearity must have been excellent already to achieve -102 dB 2nd and -108 dB 3rd harmonic. There are various versions of the TDA1541A data sheet around. I seem to remember the qualification test in the end was THD+N, so maybe in the end they were selecting for lower noise rather than lower THD?

I would guess that better matching of the internal current sources would result primarily in lower noise. Depending on the duration of the measurement, it might also result in better low level nonlinearity in short measurements. With longer integration time, this would likely average out.

So Amir, what is the integration time in your test?

 

[Koeitje]

For its age this is very good performance.

 

[Limopard]

There are some TDA 1547 (better known as DAC 7) kits out there, wonder how they perform by today's standards.

 

[holbob]

Think I had this dac in the mid noughties, in a clear plastic case that became popular on UK hifi forums - ebay seller. The only notability I remember is that it was on the Atacama Equinox shelf above my Sugen a21a. It kept cutting out, was slowly being fried but it took me much longer to realise than it should have done! Replaced it with a benchmark Dac1.

 

[Azathoth]

This got me thinking.. If I just enclose a cheap usb DAC in a large and heavy metal case, and obscure it by placing decoy boards in it and sell it for 1000 smackers you'd think I can get very rich?

 

[Ra1zel]

Nice for 1985

But if I can read my calendar right we are at the end of 2021, thus it's horrible and I vote headless panther.

 

[Madjalapeno]

Love those red traces though. That's too nice to be in a case.

 

[respice finem]

This got me thinking.. If I just enclose a cheap usb DAC in a large and heavy metal case, and obscure it by placing decoy boards in it and sell it for 1000 smackers you'd think I can get very rich?

...but at some point, the bodyguards might get too expensive

But seriously, one might be tempted to do this as DIY - like a Purifi amp build in a good old "Panzer Hi-Fi" case.