Why all the love for the TDA1541?

Seems every so often I see this particular chip regarded as the best ever made. I myself have heard it implemented several times over the years and while it is better than some of the budget dacs of just a few years ago, I cannot understand why it's still a popular choice. I understand audio is very subjective but just what does this DAC provide that today's chips can't in your opinion?
There are in general, 2 different schools of design when it comes to DACs.

The TDA1541 is from the former - more old skool design of DACs where 16 bits of data are interpreted DIRECTLY as 16 bits. These are sometimes known as R2R or ladder DACs - where each bit represents a rung on the ladder.

There's a fairly unique sound that comes from such an implementation.

The TDA1541 also implements non-oversampling (NOS) which means 16/44 gets translated to 16/44 (as opposed to 16/176.4 etc)

Others include the BB PCM1704 and on a different scale, MSB has a custom built R2R DAC on their new range that is not built from off the shelf chips.

The second school of design DACs are called sigma delta DACs which convert 16 bits (or 24 or 32) into a much higher bitrate single (or multi bit usually 5?) stream. Sigma delta DACs are much cheaper to implement and there are some quarters that don't like how they sound. Most modern DACs are sigma delta in design including the Sabre32, and even the new BurrBrown like the PCM1794/1796 etc. A variation of the sigma delta designs are custom built DACs like those from Chord, PS Audio Direct Stream, dCS, Playback Designs and Meitner Audio for instance which use discrete designs rather than off the shelf DAC chips.

Sigma Delta DACs usually measure better in some respects because they shift the noise into higher bands which aren't usually audible. They usually lack a certain "bite" when playing 16/44 material - something quite apparent when playing back the same 16/44 material on say a TDA1541. Whether that is an artefact of the NOS 16/44 R2R conversion process is debatable :) but it does have its charm.

I have an Ayon quad PCM1704K based DAC (and CDP) as well as Meitner and Playback Designs DSD DACs and I like them all. I am a bit more partial to the DSD DACs in this case but I am not a fan of the Sabre32 stuff so it IMHO doesn't pay to generalise.

I have heard a TDA1541 based DAC before and it is IMHO very very good with the CDs I fed it with.
I use to have several machines with the 1541 wonder...the best been the Marantz CD 7 which had the double crown version....now I have EMM Labs and I feel that it is better (not talking about the SACD which is why I switched to it)
Thanks for the detailed response Doogiehowser. I must fall into the Sigma Delta group of fans as I own both a standalone NOS DAC (Shek D2) and a Magnavox CDB460 and find both to be fatiguing to my ears. To be quite honest I find any of today's "budget" DACs (DacMagic, Dac-it, Dragonfly, etc) to be superior.
My favourite DAC, a hand built DAC called a Killer, uses that chip.

Its a very very musical and natural sounding DAC.

The best way to explain it is a comparison I was at with it and an ultra modern DSD DAC, an EMM DAC.

I was over at a friends place today hearing the Killer compared to his EMM Labs DAC on his Thiel 3 ways which were fed by an AR Ref 5 pre and some SS monoblocks I cant recall the name of, but they are evidently similar to the Arion 500's which was thought to be just a bit bass shy in comparison.

Anyway here is his view which will be followed by mine.

Have to say there's a lot to like about the Killer, except maybe the name which seems to rub people off the wrong way.

I was able to use Bill's Offramp to feed I2S to the Killer and AES to the EMM Labs XDS1 simultaneously and was able to A:B easily between the two using the ARC preamp.

The EMM does a lot of things right for me. But the Killer sounds more natural in the end. The XDS1 seems to exaggerate differences - higher highs and lower lows but the end result (which on its own doesn't sound bad to me) is less listenable to me than the Killer in the AB. I loved how the Killer reproduced guitars in Fourplay's 101 Eastbound (HD Tracks) which made it "easy" to follow. Where the XDS1 reproduced the music, the Killer sounded like it was an organised quartet led by the lead guitar, with the rest of band accompanying him. I really enjoyed that quality.

When we listened to the Phasure a while back, there was a similar disconnect - the Phasure reproduced voices like Pat Barber with a raspy or gravelly quality - was it more detail? I thought I heard that with Joni Mitchell's Both Sides Now (DVDA rip) on the XDS1 today. The Killer was smoother but more natural. I've only heard Pat Barber once, in a club in Chicago many years ago and from memory, it seems to be somewhere in between. It wasn't quite buttery smooth, but it wasn't quite as gravelly as what I heard on the Phasure either. If I had to choose, I'd err on the side of the Killer.

When I first heard about the Killer, about how well it sounded with vocals, I can't say I was particularly keen to listen to it. I had written it off along with many warm syrupy slow Chinese tube amps I had heard in the past. But it wasn't the case. I even threw in a bit of Depeche Mode for good measure, along with FourPlay. Over the week, I am sure I can put it through the paces a bit more with some of my more familiar material.

If there is one downside, and actually it was more of a technicality, it was that we couldn't play hires material with it. But when we were playing HD Tracks material, even with the OffRamp downsampling to 44.1, the characteristics I liked about the Killer were still apparent, even when compared to the material in native hires on the XDS1. Maybe there is something to be said about hold outs who insist 16/44.1 is good enough.

I concur with what was said above..

On all material we tried to me the EMM Labs had a 'thick' quality - things were distinct but lacked subtlety and realism. The Killer was simply much more convincing.

So the answer to your question lies in the listening - when done correctly like in the Killer, it simply sounds better to many than the modern stuff.

I know the guy that hand builds each Killer. He knows the characteristics of chips. He uses that chip because other chips to his ears simply don't do it. Why is that. Your guess is as good as mine.