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Have dacs changed so much in 10 years.

Dean Jordan

Dean Jordan

pfm Member
What's changed? If I can get a dac from 10 years ago and it has balanced outputs and a usb and coax inputs which I need what's really changed between now and then?

Is the usb none a synchronised (is that even a word, maybe not the correct one) on the older model. Can they not be a sync?

So does that leave the chip?. What may have been 5 star award winning then could be terrible now?

Just for my own mental health.

Dean
 
Hi,

Just a similar situation to having an LP12 from the 80's to wanting one of the mega £1000's ones you pay for today.

The old still play music, maybe not quite as detailed or dynamic but if the old makes you want to still listen why change?

A counter question could be with all the new technology do you really want to hear the music that is now produced, most of the new recordings I have listened to sound poor in comparison to 60-80s music, apart from classical that is.

Cheers

John
 
Yes. Today’s DACs carry a plethora of inputs and outputs, most can be a preamp and the technical aspect is worlds away from 2016. It’s not like we’re stuck with a few inputs anymore. And I prefer the sound, odd but true.
 
Dean Jordan said:
What's changed? If I can get a dac from 10 years ago and it has balanced outputs and a usb and coax inputs which I need what's really changed between now and then?

Is the usb none a synchronised (is that even a word, maybe not the correct one) on the older model. Can they not be a sync?

So does that leave the chip?. What may have been 5 star award winning then could be terrible now?

Just for my own mental health.

Dean
Click to expand...
The main point is that the dac will no longer be about 10x more accurate than the limits of your hearing, it will be more like 1000x.
 
Dean Jordan said:
What's changed? If I can get a dac from 10 years ago and it has balanced outputs and a usb and coax inputs which I need what's really changed between now and then?

Is the usb none a synchronised (is that even a word, maybe not the correct one) on the older model. Can they not be a sync?

So does that leave the chip?. What may have been 5 star award winning then could be terrible now?

Just for my own mental health.

Dean
Click to expand...
The Sugden Masterclass is a good example of a terrific sounding older dac that's still in production. The old Wolfson dac used by Cambridge too.
The older chips were often limited to 24 bit/96kHz (perhaps 192 kHz) - but is that really a limit in the real world?

It's not usually the chip that is the limiting factor but the overall design and implementation.
 
eevo1969 said:
Yes. Today’s DACs carry a plethora of inputs and outputs, most can be a preamp and the technical aspect is worlds away from 2016. It’s not like we’re stuck with a few inputs anymore. And I prefer the sound, odd but true.
Click to expand...
I'm talking about the same amount of inputs and outputs just plain Jane dac. No pre no Bluetooth.
 
Dean Jordan said:
What's changed? If I can get a dac from 10 years ago and it has balanced outputs and a usb and coax inputs which I need what's really changed between now and then?

Is the usb none a synchronised (is that even a word, maybe not the correct one) on the older model. Can they not be a sync?

So does that leave the chip?. What may have been 5 star award winning then could be terrible now?
Click to expand...
It depends on your PoV and how you see a DAC contributing to your audio system.

IMHO the Wolfson WM8740 DAC chip that was around in 2012 did everything essential architecturally right. It implemented the well-established conventional mathematics of "this is how you undo the audio sampling that the studio did", with imperfections so small I don't see how they could intrude in practice when listening to music.

It needed competent input and output circuits of course. Fashions change here regularly but technical competence is achievable. This accords with my experience that for quite a while DACs made well enough and designed according to the conventional mathematics have been interchangeable.

It is quite possible that "made well enough" does not always get achieved. If the output circuit is load-dependent the perfornance into different amplifier inputs may vary. But I like DACs that will drive "professional" 600 Ohm balanced circuits, which should make them bullet-proof in this respect.

Also, people have different ways of enjoying the hobby. If something about a DAC other than conventional performance is important and appeals (e.g. the NOS DAC or a tweaked frequency response), then some DACs may be validly perceived as better than others. I like "conventional" and "interchangeable", because that leaves me to more simply satisfy my preferences elsewhere in my audio system. But others do this differently.
 
I’m not convinced a huge amount has changed. My DAC is over ten years old, it has a first class headphone output, a well implemented volume control, multiple inputs and variable voltage output. Plus it will do hires. The only thing that has changed is Firewire is now obsolete.
 
The point is you can get higher-end old dac with a significant discount today, obviously it will be better than modern entry-level solutions. To go above that performance requires a lot of money unfortunately (that is the reason I decided to go with full Naim streamer for now rather than separate dac).
 
I cannot answer your question properly as my newest DAC is about 10 years old.
However as I understand it there are 3 main points that affect the Performance
1) Timing, clock performance. The asynchronised USB Input "throws away" the timing information from the Input Signal and only uses the clock information in the DAC. Clocks can now have timing errors that are 10x less than the ones available 10 years ago. However some new DACs, the cheaper ones?, will still be using clocks with the same accuracy as 10 years ago.
2) Power supply accuracy. A new generation of chips, they are also less expensive, now provide more stable supply voltage to the DAC chip and clocks. High performance DACs use multiple numbers of these chips for each part of the D to A conversion and the output stage ( raises the output voltage to 2V or 4V for balanced outputs)
However the implementation of the power supply 10 years ago may have been better, and more complicated to achieve the desired results, than the modern DACs.
3) Output stage. Most DACs use a standard op amp layout suggested by the DAC chip manufactuer in their applications notes.
Output stages can be improved/optimised by using other designs or more modern OP amps.

I personally have decided to be a luddite and use a DAC with a 40 year old Philips TDA1541 D/A chip. It might not have the best detail retrival but sounds "right"
 
I’d say USB interfaces and also interpolation filtering and noise shaping have evolved or improved measured performance.
Edit: I would add A better understanding of the effects of out-of-band/RF noise.

Many things matter in a DAC (input interfaces, reclocking, filtering, D/A stage, analogue stage, grounding, etc.). The latest technology might have the potential for better performance but that may not materialise (or might not be audible), and an older product might perform better.
As to which one will sound better to you, only testing can tell.
 
I have a 10 year old DAC which is still in the system. But it wasn't the DAC part that was responsible for the good sound, it was swapping the NE5532 in the output for a LM6172 op-amp. That made a world of difference.
 
cpg said:
I personally have decided to be a luddite and use a DAC with a 40 year old Philips TDA1541 D/A chip. It might not have the best detail retrival but sounds "right"
Click to expand...
It's worth quoting a post the late Charles Hansen (Ayre) made some years ago at CA:

The thing that I see over and over and over in this thread is an irrational belief in the importance of the DAC chip itself. Just about everything affect the sound of an audio product, but when it comes to DACs, I would rank (in order or sonic importance the general categories as follows:

1) The analog circuitry - 99.9% of all DACs are designed by digital engineers who don't know enough about analog. They just follow the app note. The specs on the op-amps are fabulous and digital engineers are inherently seduced by the beauty of the math story. There are minor differences in the sound quality between various op-amps, but it's kind of like the difference between a Duncan-Heinz cake mix and a Betty Crocker cake mix. 99.8% of the op-amps are used a current-to-voltage converters with the inverting input operating as a virtual ground. This is probably the worst way to use an op-amp as the input signal will cause the internal circuitry to go into slewing-limited distortion. http://www.edn.com/electronics-blogs/anablog/4311648/Op-amp-myths-ndash-by-Barrie-Gilbert

With discrete circuitry, the only limit is your imagination. You are free to adjust the topology of the circuit, the brands of the parts, the active devices, the bias current in each stage - anything you can think of. Think of this as going to a world-class patisserie in Paris and seeing all the different things that can be made.

2) The power supplies - 99.9% of all DACs use "3-pin" power supply regulators, which are pretty much op-amps connected to a series pass transistor. Everything in #1 applies here.

3) The master clock - jitter is a single number assigned to measure the phase noise of an oscillator over a fixed bandwidth. It is far more i important to know the spectral distribution of the timing variations and how they correlate to audible problems. 99.9% of all DACs use a strip-cut AT crystal in a Pierce gate oscillator circuit. It's pretty good for the money but the results will depend heavily on the implementation, particularly in the PCB layout and the power supplies (#2).

It's hard to rank the rest of these so I will give them a tie score.

4) The digital filter - 99.9% of all DACs use the digital filter built into the DAC chip. About a dozen companies know how to make a custom digital filter based on either FPGAs or DSP chips.

4) PCB layout - grounding and shielding, impedance-controlled traces, return currents, and return current paths are all critical. For a complex digital PCB, 8 layers is the minimum for good results.

4) The DAC chip - almost everything these days is delta sigma with a built-in digital filter. Differences between different chips is one of the less important aspects of D/A converter designs. Both ESS and AKM have some special tricks to reduce out-of-band noise, which can be helpful, but not dramatic.

4) Passive parts - the quality of these can make a large difference in overall performance, especially for analog. Not many digital engineers sit around listening to different brands of resistors to see what sounds best.

These are just a few of the things that make differences in the way that a DAC will sound.
 
As above I'm of the opinion that all DAC chips do pretty much the same thing, most of the improvements have been around the power supply for the analogue stage.

10yrs ago there were a few DACs with very good power supplies and analogue output stages, now it is the other way round as it is fairly simple and cheap to implement a good opamp and power supply in a DAC.

Clocking and jitter was an issue solved long ago and is now just a foo element with little or no audible benefit with external or expensive reclockers etc.
 
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