Dynamic Range - the golden key to music nirvana?


Dynamic Range – the golden key to music nirvana?

 

Before I even start I recognize that Dynamic Range (DR) is not the only thing that determines the quality of your musical experience. However, through my journey I will make the argument that chasing dynamic range may set you on the right path to your musical nirvana. Some, such as tube aficionados, have made a conscious (or unconscious) decision to sacrifice DR for other attributes for example. All I can say for now is that it has transformed my listening experience to such a degree that I feel compelled to share my journey.

 

I seriously started my journey in his addictive hobby some 20 years ago, or at least that’s how far back I can recall. I am getting older. It has become something of an obsession, like with many of us, to try to create the best possible system within my means. I think many of us could use Audiophile Anonymous meetings and therapy. It has been a long, sometimes frustrating journey, with many dead ends, stops, starts and fits. To keep up with all the developments in our little universe can be a full time job. The rewards have, however, been worth it overall. Some would maybe call me a gear-head and while that may be true to some degree let’s face it - we can’t make magic without the gear.

 

It all started a couple of years ago when I decided that hi-rez music streaming and streamers had matured enough that it was time to make the migration to this source and abandon the dedicated MiniMac with my CD collection. After buying and returning a number of streamers I was not impressed, That is until I came across an Auralic Femto. It did not take me long to decide that this was a source worth building a system with. So  my next step was to upgrade my beloved Bel Canto (BC) DAC 1.5 to a 2.7. I kept my treasured W4S STP-SE and used a pair of Bel Canto 500 mono-blocks hooked up to a pair of Acoustic Zen Adagios. So far so good – it sounded just as good, if not better, than the best CD player I could recall having in my system – there were many.

 

I had up until this point favored Class D amps more for their small size than anything else. The BC mono-blocks were wonderful, very musical, powerful amps., but I had always wanted to try a Class A/AB amp. Before long there was a Son of Ampzilla II in the house. I will never forget when I first hooked it up and my wife, a trained musician,  walked by and commented that it sounded very good. I could not agree more. The, and I will use this analogy often, silky smooth, dense, analog sound seemed intoxicating. However, after getting over the initial wonder, before long I realized that there seemed to be something missing. The sound stage seemed a little constrained and some details that I was used to hearing seemed muffled or even absent. Something that stood out was that the decay of the cymbals seemed to be cut short. I had, although I did not think of it those terms at the moment, lost the dynamics of the BC monos. Back to the drawing board.

 

After many hours of research I come to find out that Class A/AB typically operate at a maximum of 30V. The significance of this is that this also constrains the maximum DR of these amps to about 100 db as it is related to the operating voltage. So why not just increase the voltage? Problem with his is that then the transformers would have to be even bigger than some of the 200 lb Class A amps already are and the power needed would end up costing more than running your AC. Now the argument goes that a DR of 100 db is more than enough as you will start entering the hearing pain threshold after that. However, the fact remains that the DR of the human ear is 140 db so something seemed awry. I set out to test the theory.

 

Looking at my components the BC DAC 2.7 has a “class-leading” (to quote BC) DR of 124 db so that seemed ok. I could not find anything on the W4S STP-SE explicitly, but if my calculations were right the DR was probably not much above 100 db if that. I love the sound of the STP, but apparently it had to go if I was going to pursue this. Luckily for me, it turns out that the Stage II version has a DR of well above 120 db so one was quickly acquired so I could preserve that characteristic sound that I loved. The amp posed a conundrum though. Maybe I would have to go back to Class D again since the Class A/AB amps seemed limited to around 100 db. After endless research I found two viable options. The Benchmark AHB2 and SPL Performer S800. While they have different approaches to the problem at hand both operate at much higher voltages to get higher DR’s. Quite astounding DR’s at that. The Benchmark is in the mid 130’s and the SPL is well North of 140 db. I am not an electrical engineer so I can not explain how they did it in such small packages. The Benchmark uses THX modules and the SPL uses the proprietary Voltair system, which allows the SPL to operate at 120V or four times that of other Class A/AB amps achieving unprecedented DR in the Class AB category. One was quickly on the way.

 

The results, coupled with acquiring a pair of Marten Django L speakers, was very satisfying. The system exhibited all that silky smooth, dense sound associated with analog amplifiers accompanied by an increase in dynamics, as I had now come to know it, that brought out all the things I was missing before. The cymbals were decaying properly again, or at least I thought so at the time. Life was good!

 

To recap the system at that time:

 

Auralic Aries G1 (forgot to mention the Femto also got an upgrade)

Bel Canto DAC 2.7.        DR 124 db

W4S STP-SE Stage II.     DR 120+ db

SPL Performer S800.     DR 140+ db

Marten Django L

 

So looking at the chain my overall DR, given that no chain is stronger than the weakest link, was on paper in the low 120’s. I was thinking things could not improve much above that in that department at least given that 120 db is truly in the pain threshold to follow the accepted way of looking at it.

 

True to me OCD I could, however, not rest on my laurels. I have always loved the BC house sound, but it was time to try something new. If I was going to get a new DAC true to my recent findings it needed to have the highest DR possible and hence be as quiet as possible. After much research I found that here are not many that break 130 db. However, one stands out at 150 db, now that is dead quiet, the Hegel HD30. I found one from Walter at Underwood HIFI (he is Ok by the way) and the results were impressive. The enthusiastic reviews were pretty much spot on. It is a marvelous DAC. Keep in mind that the STP pre-amp is still potentially limiting the DR in the system to around 120 db, but this still did not seem to be a problem to me although my thoughts were starting to drift in the direction of “what if”. It sounded pretty amazing though so I was really enjoying my listening sessions and the potential issue slowly faded from my mind for the time being.

 

Fast forward about a year to about a month ago. I found myself having accumulated four reference level systems around he house over the years so I decided it was time to downsize and consolidate. I sold off most of two systems and replaced them with much simplified setups in order to still play hi-rez music throughout the house through ROON. Then one late night I was listening to the main system and my mind started down that dangerous “what if’ path again. I need help! This nagging feeling that possibly my beloved STP Stage II might actually be holding me back. Just maybe inserting a pre-amp with an even higher DR could improve things even more. I also had a SPL Phonitor XE in the system so to rationalize all this I thought if I sell both I would have some funds to upgrade. I also have a Phonitor X so I would still have one of their outstanding headphone amps. A man really only needs so many amps, but those rules as we know, don’t really apply to us audiophiles. So ideally, if I could find a pre-amp/headphone combo with an exceedingly high DR like the Phonitor X, but with some added consumer conveniences like HT bypass that I need for the main system I could test this new theory. So back to the drawing board again.

 

It did not take long to figure out that the only real options that could realize outstanding DR’s were the Phonitor X and the highly acclaimed Benchmark HPA4. Both have a DR in the 135-140+ range. The Benchmark seemed to fit the bill perfectly with HT bypass setup possible and a good selection of inputs and outputs that would fit into the system nicely. I was lucky enough to find a lightly used one and soon it was on its way.

 

It arrived after what seemed like an eternity. I unplugged the Stage II and the headphone amp and inserted the rather diminutive looking Benchmark with the recommended balanced cables. After fiddling with the setup for a while it was time to turn on the sound. I played some of my “test tracks” one after the other in quick succession. I was nothing short of astounded. I am not sure how to express it in words but the experience was visceral. I was hearing details on tracks I have listened to for 40+ years that I have never noticed before. The soundstage was immense. I was just getting lost in the music. The experience was so intense I had to immediately share it with someone. I felt like I had uncovered the golden key to music nirvana and that I had finally gotten a taste of what ultra high end audio might sound like. The Benchmark literally unleashed the DR of the Hegel DAC and the SPL amp. It was as if releasing a kink in a water hose the music was just cascading out of the speakers. Truly amazing! I then tried the headphone amp and the results were just as astounding.

 

So in the end I am at least convinced that higher DR has a strong correlation to the quality of the sound and the experience you will have. My system is now approaching a DR of 140 db overall on paper, or the absolute limits of human hearing, and it sounds better than pretty much anything I have heard. I can’t stop listening!

 

So what about the theory that a DR of 100 db should be more than enough? My conclusion is that this is a myth propagated by Class A amplifier manufacturers to justify not being able to do any better.

 

Happy listening!

 

P.S.  This is my experience and I am sure others have different experiences, but just maybe my journey will help someone else find their music nirvana.

 

 

 

 

 

 

 

 

 

 

 

bjorn154

Showing 3 responses by asctim

From the measurements I’ve seen, it’s very difficult to achieve a dynamic range with any speed to it beyond about 15dB in real world listening situations. If you can get 8th notes separated by 8th note rests to achieve more than 15 dB of dynamic range you have an exceptionally well controlled room. With headphones you can do much better than that, but it doesn’t come across as sounding any more dynamic.

If your room has an RT60 time of 0.3 seconds in the mid frequencies, that is considered good for a HiFi listening room. That means that it’ll take a 3rd of a second after a sound stops to achieve 60 dB of dynamic range. That’s assuming the noise floor in the room will allow 60 dB to happen. Rooms that are faster than that are generally not preferred by most listeners.

That said, I'm not against the electrical components achieving a much higher dynamic range than that. There are benefits that can be heard. But the overall perceived dynamic impact can be very high in a good room even if the system doesn't achieve much more than 60 dB dynamic range.

I have not been able to listen to reel to reel in extended sessions. I did get a chance in 2019 to hear a demonstration at the California Audio Show. In that demonstration I had no complaint with the reel to reel playback, but the room was defining the dynamic range and I didn’t perceive it to be any better with the tape compared to the LP or digital playback I had heard earlier in that room.

I read a report from a mixing/mastering engineer that magnetic tape loses some of it’s transient response within hours after the recording due to the magnetic particles drifting. He said he can hear the difference between the live feed, the original reel to reel tape immediately after recording, and the same tape a few hours later. So that wouldn’t be the total dynamic range, but the fine detail, high speed dynamics. I suspect that this may be one of the reasons some people prefer the sound of magnetic tape. Digital’s transient speed combined with some of the unnatural consequences of microphones and speakers may be tiresome and irritating to the ears. A little smoothing may actually come across as more natural sounding.

We know that reel to reel tapes and the machines they are played back on do not actually have higher dynamic range than digital recordings and digital playback devices. But the perception of better dynamics is there in some cases, so finding out more about why the dynamics seem better I think is worth further investigation.

My own experiences with setting up systems and experimenting with crossover settings, equalization, and room treatments has caused me to occasionally get a sound with unusual apparent dynamic impact. I typically get this with speakers set up in rooms, but others have reported similar effects with headphones, while experimenting with various filters. The perceived impact can go through the roof, so to speak, but it’s not clear exactly what was done to create that effect. I never tend to stick with those setups because it often works really well for certain songs but overall sounds imbalanced in some way.

@cleeds 

No, "we" don’t know that at all. The superior dynamic range of digital is only potential. The dynamic range of the vast majority of commercially recorded music fits comfortably within the capabilities of quality analog media.

I agree with you that analog media has plenty of dynamic range for excellent music reproduction. It's just not greater than digital's dynamic range, or potential dynamic range as you point out. It's no good if the mastering doesn't take advantage of it, or if the music has no need for it.

I work with a guy that has used Studer tape machines quite a bit. I asked him what he thought about the dynamics, and he said they have a hump in the bass response that can come across as punchy sounding. Depending on how fast you run the tape the center frequency of the hump changes.