The DAC's chip is not the only determining factor of sound quality. Most of a DAC's quality and character comes from the analog stage.
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My understanding is that the new John Westlake designed Audiolab players use ESS DAC chips.
They seem pretty intriguing for sure, 5 inputs including asynch USB and a clock locked transport as well.
8200CD and 8200CDQ are the models I think, the CDQ having preamp and headphone capabilities. Straight DAC is to follow apparently.
Pricing is pretty reasonable by the looks of things-sub $1500, could be a winner.
The Saber dac has become popular with many Mfgers most likely because of it's ease and wide range of applications ... It's easier to implement in a wider variety of application ... sort of like the Swiss Army knife of Dacs
What's just as important as the type of dac, is how it is implemented in the circuit ... the quality of the clock and power supplies used and placement in the circuit (close to incoming signal) can all have an effect on the Dacs performance
I have to agree with member Ballen on the importance of the analog output section and will see him on that point and raise him with the importance of a high quality power supply
Poor power delivery will cause clock and dac timing to vary ... which will result in jitter and degrade the sound
..."ok then, #$%^ the dac, comment on the analog stages"...
As far as the analog output sections I see 4 basic types
Type 1 .... Op amp chip based .... problem is when a sudden high current demand is called for on the musical peak ... the little chip Op amp can run short on power momentarily and ... because the Op amps are in a negative feedback loop in the analog section ... when they run short of power they create an oscillation in the negative feedback loop ... because the feedback loop can't create the proper balance of incoming signal to outgoing signal
This momentary oscillation due to power shortage in the feedback loop causes an audible ringing on the peaks ... and can be perceived in the presentation on the peaks as .... ringing ... momentarily narrowing/congealing of sound stage ... limiting of dynamics and in general a screechy or shout -t-ness on the end of the Peak ...but only momentarily ... under normal load none of this is occurs
This distortion is brief and momentary and occurs only on the peaks when the Op amps can't deliver the current needed to supply the Feedback loop and drive your Inter Connects ... your system sounds fine then the demanding peak comes along and it goes to Hell in a hand basket for a brief moment and you think it's your system's amp that is running out of horse power ...
No you don't need a new power amp it's your CD player's Op amp running out of current
Substituting a Op amp with discrete components vs the all on one Chip based Opamp can offer some improvement ... but you're still in that Cranky Negative Feedback Loop
Type 2 .... Op amps buffered by tubes in the output section ...." Two wrong don't make a right" ... now your adding the Tube's distortion to that of the Op amp's problems and you are still in a Negative Feedback loop .... moving on
Type 3 .... Discrete Class "A" no Negative Feedback Tube based output section ... No Op amps to run out of steam or Feedback loop to Oscillate ... just have to pick your flavor of tubes ... sorry I'm not a TUBE guy so I can't help here
Type 4 .... Discrete Class "A" no Negative Feedback Solid State FET output ... No Op amps. No Feedback Loop. and less complicated and expensive than the learning curve required to get tubes right
Just some thoughts on Dacs ... I think all 1 bit Delta Sigma dacs sound about the same ... it is the power supply and analog out sections that contribute more to the players sound than the Dac
Take a player and rotate all the different Delta Sigma dacs available, in and out of the players and the players' will probably all sound the same ...
Take your ESS dac and put it in any number of players with different analog out sections and power supplies types (switching vs Linear) and it will sound different in every machine
That was an excellent answer. Based on personal listening and reading various articles on this topic, the power supply quaility and analog circuit have far greater performance influence than the chioce of a particular chip. Shegeki Yamamoto who has a stellar reputation for building SET amplifiers,tube preamps etc. came to the same conclusion when he entered the digital domain. He believes that discrete analog circuits withot negative feedback will sound more musical and natural than most OP amps in general. He also says you must place much effort towards a very high quaility power supply or the result will be unsatisfactory. His first DAC used an ultra simple SS discrete circuit,single end(not push-pull) with a large transformer and power supply. He`s a tube guy for sure but said in this situation SS provided the more simple and pure signal pathway. There is a great review and comparison to his latter tube version on 6 moons. I own the solid state version and it`s superb with my tube amp and tube linestage.
Charles thanks for the kind words ... I've also enjoyed good success with Buffering the output of SS players that use chip Op amps with an inexpensive outboard SS Buffer
These are 1 to 1 gain amps that maintain voltage while increasing amps ... I think they call them Current Dividing Buffers ... they can also help in lowering Tube based players high output impedance .... these buffers will lower it
The Buffer takes the respondsibility of driving the interconects off the Op amps ...
Because the load on the Op amp is less and more stable ...
They don't overload when a demanding passage comes along driving the negative feedback loop into oscillation
The player I use is a Ayre D1xe ... Class A no neg F/B FET analog out and an external power supply with Galvanic isolation between audio and video ... inductor choke input as well as caps for common and diff mode nose at the IEC
The dacs on the Ayre are seldom used multi bit ladder dac style ... 1704K Burr Brown ...
my review of this dac appears on audiophilia.com. i welcome any feedback.
i may sell my ps audio perfect wave tdac, but i shall try a copper hdmi cable before taking such action.
it is a great product. i have experimented with digital cable and don't hear huge differences between, coax, xlr and toslink.