Holographic imaging


Hi folks, is the so called holographic imaging with many tube amplifiers an artifact? With solid state one only hears "holographic imaging" if that is in the recording, but with many tube amps you can hear it all the time. So solid state fails in this department? Or are those tube amps not telling the truth?

Chris
dazzdax
You think great DACs are realtively immune to the transport use? I always naively[?] felt thgat a good DAC should be able to deal with whatever jitter the source might present; maybe we are there

Interesting question - I wonder what experts think?

I suspect some DAC's are becoming relatively immune to digital source and jitter. Clocks and algorithms continue to improve so inherent jitter reduction is improving also (we went from PLL to double PLL's to buffering and asynchonous sampling). However not all forms of jitter are the same so the quality of the rejection may vary depending on what the source is creating. Some will reject a greater variety and a greater level of jitter than others so in essence they might sound the same with most transports. Of course some combinations, even older ones, may just happen to work really well, as the transport jitter is just the type that the PLL loop can deal with.

An old AES paper showed that certain forms of 20 nanosec jitter were inaudible - this is a huge amount by modern standards - so if people hear jitter artifacts then it may not even be an issue of "how much jitter" at all but a more sinister issue of "what type of jitter". If you consider source music and jitter may be related to eachother (IMD) then there are probably an infinite number of combinations. Added variables are that one may not be able to hear it, or your speakers may hide/mask it, or the track may be hypercompressed (other distortion dominates), or the track was recorded with a jittery A to D in the first place (so nothing can fix it)

I suspect we are way closer to jitter immmunity to the point of inaudibility than we were in the 80's and even the 90's. I wonder what others think - Are we really there?
I don't know if we're there yet categorically but I am of the opinion that there is no good technical reason I know of why it should be a big problem these days.

My ears may not be the gold standard, but in general I am not hearing sound issues with digital sources that I can clearly attribute to jitter.

Poor or at least flawed recordings seem to be the culprit in most every case where I hear clear deficiencies IMO, and this has been getting better over time as well.
>>Running my $180 Oppo through my Playback Design MPS-5's DAC makes the Oppo sound better than an Emm,<<

Right.

And putting a set of Corvette tires on your Ford Pinto makes it handle like a Porsche.

LOL
The Mapleshade label, for example, uses different than norm recording technique, where microphones ( usually only two) placed on each side of human head shape fixture to resemble left and right human ears at the 'correct' height from floor. In addition, there is no additional processing to the signal. And then there are other basic good recording practices being employed at the same time, like shortest possible cables from mics. All combined generates pretty different and realistic sound quality- in a right (well balanced) system, where you get some of the bloom and air that a real live music event generates. In less than stellar system (My old components), sound quality is still comes across as real sounding minus the air and bloom.

In both cases, IME, holographic sound is not to be found

I am sure there are other labels employing similar techniques..
Bill, we're talking about the relative value of the DAC vs. the transport. Apparently you can't hear well enough to realize that a DAC is a very important component in the digital chain.

Do you dispute my finding? Have you run an Oppo's digital-out signal through a dCS or Emm DAC? (I know that you're very unlikely to have done it with the PD). If so, wasn't the improvement large and dramatic, or did you hear next to nothing? I DO concede that preference for the Emm vs. the PD is a personal sound preference, but I know several people, including myself that prefer the PD sound to the Emm sound. Both are very good, IME.

To a degree, Emm has supported this finding by using relatively inexpensive transports in their combo players. Of course, they use way better quality than Oppo, but not as high a quality as the Esoteric or the proprietery high-end transports. Despite this, their CD/SACD players are highly respected.

Still, IMHO, a good transport can add a significant performance increment to a good DAC, but the DAC is relatively more important by several orders of magnitude. (When I speak of the DAC I'm referring to the whole DAC/Clocking sampling/timing scheme, not just the DAC in isolation). Analog I/O is also very important to the end result. The very best players put all these elements together.

Dave