Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems Is this a valid test to see if my ears will hear benifits of Apodizing Upsample?

The idea is a bit like the ReProg function of the AnchorBay VRS: remove bad deinterlacing (extract interlaced signal from progressive signal) and deinterlace the signal proper. So remove the bad 20kHz brickwall filter and apply a proper lowpass filter. However, to be able to gently fall off above 20kHz you need more than the 2kHz space that the original CD signal has. Therefor you need a higher frequency signal and the easiest is to double it. In theory the 24kHz bandwidth of a 48kHz signal already doubles the space for the fall off, which makes a big difference

New units are delivered with the V1.05 installed, so obviously it is not in beta. Considering multiple customers have asked Meridian about this firmware they should be aware of the omission.

Yes, the downsampling will introduce pre-ringing, unless it is a causal filter (no delay), which is preferable for real-time application. At least the delay will be as minimal as possible, hence reducing the pre-ringing as much as possible.

George, I cannot possibly give you any of the technical explanations everyone else here said and I dont know what will happen with the G68 but as Mr. Meridian said- the difference is quite noticeable. I would say its like going from one version of a Meridian product to the next version- the sound is cleaner, clearer, and not in a clinical way, its even more silky. You might lose a drop of bass thump because my experience is some of the bass thump I was hearing prior to this must have been this distortion that has now been removed. Its really quite an accomplishment Meridian have pulled off!

That would not invalidate my test. It would just make the difference even wider and easier to hear. Even if I do hear a difference in my test it does not guarantee I would hear the HD621 going the other way. But if I can't hear the difference in this "worst case" (largest gap) then I'm not sure I'll hear the difference going the other way.

Axle, just what I want to test. Is the HDMI output with HD621 improved over the SPDIF direct into the processor? Most here have said it will be, so I suppose I'd better bring my check book. Hope Steve's (dealer) not reading this.

You didn't read my post. I did it on SACD, 24/96 Native Flacs and 24/96 Bluray.

If "downsampling" is "bad" (As you are implying) then it should be even easier to hear the difference (how much the sound is degraded), the point is I don't. So why will I hear it going the other direction (which will be even less of a difference, because it won't be true hi-res)? And what I'm starting with won't be damaged by a downsampler.

I don't see your argument with interfaces. If anything HDMI will be worse and HD621 eventually transmits over SPDIF anyway (for 99.999% of us at the moment).

But I appreciate your honesty on what to expect and it's not something you toggle and immediately hear the difference. That is more believable than some other claims I've read.

However, I don't find my system fatiguing at all right now even at quite high volumes. I'm quite happy with that.

I would also think the whole apodizing thing has the least impact on low frequencies.

George, the answer or much of the answer is provided by Robert Harley, TAS, August 2009. He confirms Meridian`s claims and the comments here in this thread how the difference is so obvious that it will “slap you in the face”. RH when reviewing the 808.2 referred to being “immediately stunned` by the “mind-blowing” improvements in CD playback from the 808.2. That all results from the apodising filter. That TAS also has a related interview with Bob Stuart.

RH`s key points were:

1. CDs limitation is not just the 44.1/16 sampling

2. The problem is a particular distortion, pre-ringing, that is unique to digital recording

3. Pre-ringing is avoided by 96kHz sampling that therefore sounds better

4. Meridian`s apodising filter removes pre-ringing imprinted in all 44/16 CDs

5. The results is a clearer sound with a fundamentally different and better soundstage and dimensionality that is very much like high res sound

TAS January 2010 gave the Technology Breakthrough of the Year award to the 808.2, ie, apodising filter.

When I first head the 808.2 through 7200s I too was immediately impressed and stunned by the sound. Fortunately it did not feel like a slap in the face. Maybe a slap in the face is reserved for the continued doubters.

Ok


Ok, I'll buy that.


But what if I can't hear the benifits of Native 96Khz in first place? Because I don't hear a difference taking something that is "Ideal" and down sampling it.

Or Meridian can Down Sample in their consumer PreAmp better than any professional downmixing CD equipment?

I don't deny the pre-ringing problem and Meridian's fix. I just question if I'll be able to hear it, based on basic test I did.


I think there is more to an 808.2/3 than apodizing.


Sounds too good be true.

Well obviously I did, but I missed a few words - there's a difference. Don't exaggerate.


I see your point, as I did before, but my own fundamental point remains the same: why attempt to discover whether you will want an HD621 with this unproven test when you could just borrow an HD621 from your dealer? Wouldn't you normally advocate buying something only if you can hear the difference in an audition of the product in question?

I don't have HD621 so will use a video analogy. Based on this, I believe the test is flawed.

I only have Freeview TV, currently SD in this household. However, much of the programming has originated in HD. Whilst the transmission nitrates remain unchanged or have degraded as more channels are squeezed into a multiplex, it has been easy to spot when programs have started to be made in HD. Even though I am watching in SD, the HD originated program is better quality.

I believe that the same may be true for your test. Starting with an HD source and creating SD from it will produce something closer to the HD than an original SD source, which in the case of Meridian audio into DSPs will have been bit extended and dithered).

This difference will he heard by different people in different ways but for those of us whose hearing is not so good, I believe that the difference between 96-48/88-44 will le less audible than 44-88/48-96 + special sauce so just because you can't hear downsampling of hires material doesn't mean that you won't hear upsampling/apodising of CD material.

I think if you can't hear difference of HD621 then you should just concede that your hearing is shot and sell your M kit and buy a �300 Yamaha box instead

Have a watch of this video.

It's long, but the first 9 minutes has some interesting points on how we listen, expectation bias etc.

Steve.