What is 'incompetent digital' ?

[Mivera]

One of the things I've found which makes an improvement to the SQ of DACs using that chip (TDA1543) is working around the limitations of its internal biassing current source. This is something that at least one other designer found independently too. The chip hasn't sufficient power supply rejection with that CCS in circuit. Fortunately on that device its a simple matter to turn it off and build an external one to do the same job. Cost in BOM terms is single digit cents.

Don't ever tell a seasoned, golden eared, cream of the crop audiophile that a 15 cent part could have a bigger impact than a $5000 set of cables. One thing I have learn't from audiophiles on forums is, it only matters if it's on the outside of the box. Once you cross the barrier of the binding posts/power inlet, analog/digital connectors, it doesn't matter anymore.

 

[Opus111]

I've noticed there's a strong aversion amongst audiophiles to upgrading internal parts, presumably from FoLRV - fear of losing resale value.

 

[Mivera]

I've noticed there's a strong aversion amongst audiophiles to upgrading internal parts, presumably from FoLRV - fear of losing resale value.

Yes they have that fear, yet have no problem spending triple/quadruple the cost of the gear being modded to get inferior results using external tweaks. Some of the stuff people buy to combat problems that shouldn't exist in the first place make me cringe.

 

[March Audio]

I'm most certainly not on the same page as Ethan, but cheap or expensive is rather beside the point - I've not found a DAC which didn't benefit in terms of delivering more enjoyable sound from having various issues fixed up.

One of the first DACs I played with is the one Amir's going to buy - the Muse 4*TDA1543. This has a number of design issues which can be fixed for barely any expense to increase the enjoyment factor.

Isnt that a perfect example of what Ethan was referring to? An issue with a 25+ year old design?

Whilst I have no doubt that many designs can be improved with tweaks I think his post shouldnt be taken too far out of context, which is the differences are small enough that they shouldnt be causing people to lose sleep at night.

 

[Opus111]

That's one thing your more modular design approach could address - if its only a replaceable module which needs a tweak, they could keep the original module for swapping back in if they ever need to sell.

I would agree about deploying cables as tweaks - but there are very attractive margins on those for the dealer so don't expect tweak-by-cable to go away any day soon.

 

[Opus111]

Isnt that a perfect example of what Ethan was referring to? An issue with a 25+ year old design?

Not from how I read what he wrote - that Muse DAC isn't a particularly old design. And I recall he also said 'incompetent digital' applied to old digital which 'actually sounded bad'. But given he doesn't mind the sound of 'cheap' stuff, I doubt very much this will sound bad to him.

 

[Mivera]

That's one thing your more modular design approach could address - if its only a replaceable module which needs a tweak, they could keep the original module for swapping back in if they ever need to sell.

I would agree about deploying cables as tweaks - but there are very attractive margins on those for the dealer so don't expect tweak-by-cable to go away any day soon.

Yes that's the whole reason that it's built with that level of modularity. Engineers always find better ways to do things. But when things are all built onto 1 board to reduce manufacturing expense, you must dispose of the whole thing to upgrade. Great example here:

 

[March Audio]

Not from how I read what he wrote - that Muse DAC isn't a particularly old design. And I recall he also said 'incompetent digital' applied to old digital which 'actually sounded bad'. But given he doesn't mind the sound of 'cheap' stuff, I doubt very much this will sound bad to him.

Your were referring specifically to an issue with the chips CCS - a 25 year old design.

 

[Opus111]

Yes that's the whole reason that it's built with that level of modularity. Engineers always find better ways to do things. But when things are all built onto 1 board to reduce manufacturing expense, you must dispose of the whole thing to upgrade. Great example here:

I agree 100% - I feel those 'all-in-one' PCB designs suck so badly. For one thing you really need different numbers of layers for the various parts of the PCB. Having the transformer sitting on a multilayer PCB (i.e. greater than just 2) is such a waste of PCB real-estate. But the digital parts might want 4 or 6 layers to keep the noise down.

 

[Opus111]

Your were referring specifically to an issue with the chips CCS - a 25 year old design.

And as far I read him, Ethan wasn't referring to chips, rather finished products.

 

[March Audio]

OK, here are a couple of test files. I'll explain precisely what I did to them in a few days time and we can argue the toss over the validity of the exercise then

Have a listen for different perception of dynamics, as per Opus' hypothesis.

If people can PM me their observations rather than post them in the thread we can avoid influencing each other. I will anonymise the comments when I report back.

Have fun

http://gofile.me/2vnEF/hO4u99Ykj

Did anyone get a chance to listen to these files?

 

[Mivera]

I agree 100% - I feel those 'all-in-one' PCB designs suck so badly. For one thing you really need different numbers of layers for the various parts of the PCB. Having the transformer sitting on a multilayer PCB (i.e. greater than just 2) is such a waste of PCB real-estate. But the digital parts might want 4 or 6 layers to keep the noise down.

It's simply designed like that to reduce manufacturing costs. Performance is secondary. And they would rather just have you dump it for 1/3rd the value every 2 years and buy all new if you want to upgrade anyways. Products designed for sustainability are a rare find these days.

 

[March Audio]

And as far I read him, Ethan wasn't referring to chips, rather finished products.

That obviously is of no relevance - this would be an issue with all designs that use that chip assuming that the designers have not discovered and rectified that issue.

Anyway, arguing this pedantry is pointless and misses Ethan's major point, which is that the differences are small.

 

[Opus111]

Anyway, arguing this pedantry is pointless and misses Etahns major point, which is that the differences are small.

He was saying that he didn't notice large differences which impacted his enjoyment - that's his subjective impression. However everyone listens differently - I notice significant differences in satisfaction of listening between digital.

 

[Opus111]

It's simply designed like that to reduce manufacturing costs. Performance is secondary. And they would rather just have you dump it for 1/3rd the value every 2 years and buy all new if you want to upgrade anyways. Products designed for sustainability are a rare find these days.

I wonder if the service guys warm to products designed that way. Suppose you need to pull out a component or two in the power supply, isn't there a danger of damaging some of the really fine pitch SMT parts when handling the board?

Agreed that obsolescence is in the main the name of the game. Huxley observed that decades ago about Western civilization.

 

[Mivera]

I wonder if the service guys warm to products designed that way. Suppose you need to pull out a component or two in the power supply, isn't there a danger of damaging some of the really fine pitch SMT parts when handling the board?

Agreed that obsolescence is in the main the name of the game. Huxley observed that decades ago about Western civilization.

No the boards all plug into solid header pins. Besides they must be shipped to me to install the upgrades.

 

[Opus111]

I wasn't talking about your boards Mike, those are cool, I was referring to the T+A example you provided.

Perhaps as you suggest its not designed for being serviced at all - just bin it and buy the latest model?

 

[Mivera]

I wasn't talking about your boards Mike, those are cool, I was referring to the T+A example you provided.

Perhaps as you suggest its not designed for being serviced at all - just bin it and buy the latest model?

Yes tweaking that board wouldn't be something I would attempt. It's just engineered to be disposable. There's not a lot of difference between it and it's predecessor, but it will cost you $3995 for the $10 tweak.

 

[NorthSky]

@Opus111 & Mike, what's your take on Wolfson* Dacs?

→ http://www.head-fi.org/products/questyle-cas192d-dac/reviews/11230

* Wolfson Microelectronics - WM8741

 

[Opus111]

I only have very limited experience with Wolfson (the WM8740 which is one of their older designs) - it can be improved a fair amount (subjectively speaking) by modifying the approved application circuit. But ultimately it doesn't deliver on dynamics and HF purity to my ears.