Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems Proven: Redbook CD Sounds the Same as DVD-Audio

Quoted from the article:

"Please note that this is not just a disagreement with the cloud-cuckoo-land audiophiles but also with the highest engineering authorities, such as the formidable J. Robert Stuart of England`s Meridian Audio"

HERE

There was some strange "when limited by a 16/44.1 processor" and such.. But I think they were trying to rather see if 16bit 44KHz was good enough. They downsampled SACD/DVD-A tracks to 16.44 to see if they could hear a difference.

This is somewhat believable in that I've always felt 20bit was plenty and could not hear any improvement beyond 20bits. But there is no 18bit sources to listen to, to see where that threshold actually is.

I also agree that all 16bits are critical and with all the processing that goes on (especially in Meridian Setups and Hybrid Digital Volume) those few extra bits of headroom is critical so as not to drop below 16bits anywhere throughout the system.

By going through an single A/D/A he can maintain perfect dynamic range so that nothing is lost. But in practice 16bits is tight. For example using analog outs of a HD player and then going through a different brand A to D (in different box) may not have perfectly match voltages and so you lose a little range. It's nearly impossible to set the sensitivity to 100% without clipping on all material, so you always back off some; well there goes a bit or two for that safety margin.

EDIT: This ALL depends on how good that first A/D stage is. It would be cool to do this test purely in the digital world. Hmmm, if we set our 24/96 DSP speakers to non 24/96 it would be very nearly the same test. Except I think Meridian would downsample to 18/48 not 16/44.

Given the attention to detail that M HQ has always placed on what is publicly said, it would be really interesting to know if Mr. Stuart has ben quoted correctly in that article, and if it was contextual or out-of-context. Really interesting.

My mistake.

Proven what to who, by whom?

The whole tone of that article sound wrong to me. The guy is trying to gloat and using Bob Stuarts name to somehow gain credibility.

If only life where as simple as that, but it isnt.


Blind AB Tests are not as valid as they may imagine.
Music is a personal emotional experiance and you cant easily A/B it.

If you dont like classical music, any amount of A/B Testing wont get a valid result. The same goes for any genre.

I am sure they will have answers to all this, but I just dont like the tone they use.

Bob Stuart has for a long time advocated that 2 channel is not enough, so what are they saying here?

Bob Stuart recomends keeping the signal in the Digital Domaine untill the last Moment for very good engineering reasons. This test seems to disregard this, yet try to bring him to some dissrepute.

It is a Non Test in a Trifield DD-Plus True HD audo DTS-Master etc world.

Random thoughts, Chris

I think to really do this right you need to get an expert in DVD-A mastering/ authoring and the same with SACD and then Redbook and then do the test. But I am a little surprised in the sense that I would think the higher res formats would offer more dynamic range.

best regards,
Jerry

The Audio Critic needs to read Bob's papers on the topic before he starts down this road.

I'll give everyone a gentle nudge and remind them that the paper mentions maintaining a ~20-21 bit channel from capture to delivery at a sampling rate of ~65kHz for complete transparency to even the listeners with the highest tested acuity.

The use of 24-bits and 88.2 and/or 96K sampling is for convenience rather than anything else.

Cheers,

Just to restate what this Paper is claiming

• That when the ANALOG Output
• Of an UNKNOWN DVD-A Player
• With an UNKNOWN D/A Conversion stage
• And Then Processed thru an UNKNOWN 16/44 A/D/A Processor

That the resulting Music is Audibly indistinguishable from regular CD Replay

Are we supposed to be surprised by this?? Most sane people here would accept that there is a significant difference between the ANALOG Outputs of various CD and DVD-A Players, i.e. a Meridian / Naim / Arcam / Mark Levinson player will sound different to a Sony / Pioneer Player when the Analog outputs are used. When outputting DVD-A thru the Analog outputs, surely the same issues will apply....

And THEN when you take that Output and reprocess it thru a 16/44 A/D/A stage (allegedly to “level the playing field”), again we`re supposed to be surprised that “DVD-A” sounds the same as 16/44 CD???

An analogy would be a Paper that states that a Porsche / Ferrari is no faster than a Prius when ALL are forced to drive at the Highway Speed Limit of 60mph. (And we`re supposed to be surprised at this)

If this is supposed to be “Incontrovertible” proof, then..................

One also needs to consider this Paper against the background of the numerous other Papers out there with Diametrically opposite claims of superior Audio performance of 96/24 Tracks compared to 44/16 Redbook CD Replay. One Paper set against many others, with 180 deg opposite claims, hardly qualifies as “Incontrovertible”

To add to John`s earlier post, Bob Stuart stated in several interviews in the early days of DVD-A, that he considered 22 bit word samples at a 72Khz Sample Rate to be sufficient for Optimum Music replay. However, given that 96/24 had already been written into the DVD-V Specs years earlier, the decision was made to use 96/24 and 192/24 as the basis for DVD-A.

I agree that there are some significant areas of concern here, most notably the D->A->D processing stage and the 48/16 processor.

FWIW, Ken Liles posted a link to a thread started by Amir (from Microsoft). His first post is extremely relevant to this discussion. Whether it's right or wrong is another matter, but it's a pretty convincing post. I'm trying to figure out how this squares with JRS' 72/22 (or 65/22) optimum.

http://www.avsforum.com/avs-vb/showthread.php?t=960826