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Wondering if you really would be able to tell the difference between CD quality music and high-resolution audio? This survey says yes...

We're pretty convinced by the appeal of hi-res audio. If you have a decent system and a good quality recording, there's a distinct jump in quality over compressed music. But plenty of people still have their doubts.

The Queen Mary University of London (QMUL) carried out a study comparing data from over 12,000 trials in 18 surveys where people were asked to compare different music files. It found that they can hear the difference between hi-res audio and CD quality files, but that a little 'training' - presumably pointing out aspects of the music to listen out for - might be needed. 

"Our study finds high resolution audio has a small but important advantage in its quality of reproduction over standard audio content," said Dr Joshua Reiss from QMUL. The trial found that with 'training', subjects could "distinguish between the audio formats around sixty per cent of the time". This was apparently a 'dramatic' increase on the percentage who could differentiate before training.

MORE: Explaining the science behind hi-res audio

Dr Reiss said: "Our study is the first attempt to have a thorough and impartial look at whether hi-res audio can be heard. We gathered 80 publications, and analysed all available data, even asking authors of earlier studies for their original reports from old filing cabinets. We subjected the data to many forms of analysis. The effect was clear, and there were some indicators as to what conditions demonstrate it most effectively. Hopefully, we can now move forward towards identifying how and why we perceive these differences.”

More after the break

The results suggest that hi-res audio isn't a cut-and-dry issue for most people without a little pointing in the right direction. We've contacted QMUL for more details on the report, which is due to be published in full in the June issue of the Audio Engineering Society.

MORE: 4 of the best hi-res audio systems


Gilboa's picture


IMO if you have to point out the differences to people, that's not a good thing! As for my own experience, any differences are very small. The only thing that stood out to me was a slight improvement in 'air' around the instruments and vocals, but I'm in my 40s and can't hear above around 14kHz anyway, only children can hear up to 20kHz. None the less I still wish high-res audio streaming and downloads were the norm. The bandwidth and storage is certainly available for it now, and it shouldn't cost the music companies anymore dosh to do it.

Graham Luke's picture


So the Queen Mary University of London (QMUL) carried out a 'study', right?

That would be a study rather than, say, empirical testing using a controlled environment with blind A/B testing...?

The Boston Audio Society (BAS) carried out the latter. The results of their scientific research determind unequivocally that listeners could not discern between CD quality and so-called 'hi-res', given the source material was the same for each format.

They even wrote a paper on it; '24-192 music downloads are very silly indeed'.

The rest is...er...(BS).


Leon Yiu's picture

Just my 2 cents

So I am sure everyone's read this article


and that's why Hi-Res audio has failed to take off, because it's not rational.

I was looking for a song from this Japanese artist which wasn't available on itunes, the only copy I could find was in 24 bit 96khz. Since I have plenty of hard drive space, I didn't bother downconverting it, the more I listened, the more impressive it was, it had qualities I'd never heard with CD audio, the sound was more realistic as a whole. I obtained more music from that source as could be that it was from a higher quality master, same effect.

I decided to re-examine the evidence to see what may have been overlooked.

Regarding the 16 vs 24bit issue, I am on the fence about this one, 24bits dithered down to 16 bits reproduces 120db of dynamic range distortion and noise free in the audible spectrum. In practice of course you'll get a lot less because of the electronics. I'll come back to this.

Regarding the Sampling rate, the article states that

"All signals with content entirely below the Nyquist frequency (half the sampling rate) are captured perfectly and completely by sampling; an infinite sampling rate is not required. Sampling doesn't affect frequency response or phase. The analog signal can be reconstructed losslessly, smoothly, and with the exact timing of the original analog signal."

This is the part that I dispute. I have studied Fourier Transforms during my undergraduate Mathematics course at the university of Southampton.


The sample rate has to be greater than 2 (not equal) to capture a frequency, otherwise you get aliasing as demonstrated in the diagram in the Quora answer above. However I dispute that it's a perfect capture or reconstruction. Modern low-pass filters are very good and introduce minimal distortion, reconstruction of the Signal also results in aliasing.

I've seen debates in forums become very heated. A commenter on this thread called AndersVinberg very much sums up my thoughts on the Nyquist Shannon Sampling Theorem. It's a mathematical equation whose proof is incomplete, that perfect reconstruction can only be done in practice, with an infinite sample rate which is unrealistic.


I wanted to point out an industry paper about misconceptions of the Nyquist Theorem


To keep the comment short I'll highlight the conclusion.

"In designing sampled-time systems, the variables that we need to juggle are signal accuracy (or fidelity) and various kinds of system cost (dollar cost, power consumption, size, etc.). Measured purely from a sample rate perspective, increasing the signal sample rate will always increase the signal fidelity. It will often decrease the cost of any analog antialiasing and reconstruction filters, but it will always increase the cost of the system digital hardware, which will not only have to do its computations faster, but which will need to operate on more data."


Chord electronics, whose founders include an avionics engineer, and talks about the timing of transients, and how their DAC's digital filters go about remedying this. With better DAC's, the difference between redbook CD and 192khz is smaller because of better digital filtering.

Since the Hi-Res audio consortium require speakers/headphones to be able to reproduce frequencies up to 40khz for certification, I don't think they themselves know what they are selling. The Shure Se846 goes up to 20khz as does the AKG Y50 and What Hi-Fi reviewers have mentioned these products sound better when playing back Hi-Res tracks.





Graham Luke's picture


I'll get my coat.

ruffian's picture

Too many different flavours confusing the matter

I've got 3 albums in hi rez. The first I bought was Kate Bush "50 Words for Snow" (from her website) which I also had on CD. Although beautifully recorded I just couldn't tell the difference, so concluded that at my age (50) I probably couldn't hear certain frequencies so wouldn't bother.  

Then i I bought Jean Michel Jarre's "Electronica 2" (from 7 Digital) in hi res 24/48 and comparing it to a straight CD rip I did noticed quite an improvement. More weight and depth. 

This week I bought Christine and the Queen's "Chaleur Humaine" (24/44.1) (qobuz as it wasn't available in hi rez from 7D)  I again I notice the vocals seem clearer. Each one seems to have different bit rate/sampling etc and I don't really understand what the differences are, which I should buy. 

I found each each album was available in differing quality for different websites. There's no one stop shop guaranteeing the best quality  - having to check three or four different sites when I want an album is annoying! I may stick with CD unless it's really special. 

Graham Luke's picture

The Source...no, not the stuff you put on your chips.

Unfortunately there seems to be no way of knowing the source of the different formats when buying.

I have all 7 of Arnold Bax's symphonies in the computer at 16/44.1 and downloaded in that format from an online music site. The album is also available as a hi-res download.

Now, my copies sound excellent (Shure IEM's via Dragonfly Red from iPhone) and I'm confident they were sourced and down-sampled from the original masters courtesy of the wonderful Chandos label. I presume the hi-res files will also have been made from the same master copies.

The big question is, would my...er...late 50's ears be able to discern a difference on my current equipment between all those bits and kilohertzes?