Digital Harshness - can it develop over time?

polkatese

Gents,

First of all, before I get to my question, let me ask you these questions:

1. Definition, how would you defined Digital Harshness?
2. Assuming that Digital Harshness can only exist in the signal path, within the constrained and/or realm of CDP/DAC and Pre/Pro, how likely pre/pro be the reason for it?
3. Recording quality - remastered versus recent (10 years or less) - how much of it matters?
4. Introduction of tubes into the chain - softening or coloring the sound, what is the true measure?

5. Lastly, can it develop over time due to changing characteristics/burn-in of tubes, if the CDP is in the chain, thus increasing the likelihood of the presence of Digital Harshness?

Thanks..

dragon1952

OK, I'll try

1. I think of digital harshness as the unappealing sound in the highs that can cause listener fatigue and/or the occassional "cringe". It makes your system not real fun to listen to and can unconsiously make you avoid the listening experience.
2. The pre/pro can definitely add it's signature to the sound but it's all in the analog realm unless you are going into it with the digital signal and letting it do the digital to analog conversion. It could certainly exacerbate the problem even if you were going into it analog, depending on the quality of the pre-pro.
3. Recording quality can definitely be the culprit (and maybe most often is) even if you have a great system. Remastering and/or age of the recording is immaterial. Either it's a good recording or it's not. A current remaster does not guarantee anything.
4. Tubes can 'soften' the effect I believe but are not a cure all.
5. No I don't think it can change over time, assuming nothing has changed, unless your tubes are going bad. Maybe you are just becoming more aware.

Other things that can exacerbate the problem could be cabling, speakers and the room itself. It might be helpful to know more about the components and cabling in the chain as well as the listening environment.
I fought this problem for years and am now pretty darn happy. Even the worst sounding CD's I own actually sound pretty good now.

polkatese

Rob, Sean: thanks for the feedback.

At which point high resolution components become too revealing?

Yes, this hobby is a ****! but at least, it doesn't talk back!

everyone else, please expound...thanks.

organ

Looks like you've got everything covered.

It's too bad most recordings suck with some being unlistenable due to excessive harshness in the high frequencies. Makes you wonder if the recording engineers care about their work at all.

SuperDave

Got a box set of Journey cds that had the worst high end harshness ever. I used to play the same on vinyl and it was a lot smoother. Don't know if it was a bad conversion or what. Yea I know they sound that way anyway, but I guess I'm saying the source makes the biggest difference. A good recordinq always sounds best.
SD

Tour2ma

polkatese wrote:

1. Definition, how would you defined Digital Harshness?
2. Assuming that Digital Harshness can only exist in the signal path, within the constrained and/or realm of CDP/DAC and Pre/Pro, how likely pre/pro be the reason for it?
3. Recording quality - remastered versus recent (10 years or less) - how much of it matters?
4. Introduction of tubes into the chain - softening or coloring the sound, what is the true measure?
5. Lastly, can it develop over time due to changing characteristics/burn-in of tubes, if the CDP is in the chain, thus increasing the likelihood of the presence of Digital Harshness?

I think #3 is key. Not that mixes can't be garbage today as all audio engineers are not created equal, but hopefully you have to go back more like 20 years to find true harshness.

Many early CD's were rushed into production to cash in on the latest "craze". Many labels were in such a rush that they did not even bother to remove the RIAA equalization built into the master tapes. RIAA boosts highs and reduces lows for mechanical reasons during vinyl playback. All phono pre's compenstate producing a flat signal.

Enter the CDP sans RIAA compensation... and the "harsh" CD was born. Exaggerated highs = shrill and hollowed out lows = no wamth... take this as my definition, answering Q#1, if you like. There can be more to remastering than removal of the RIAA equalization, but it's a key element.

On your Q#2...
Again I think it's more likely to be DAC related in years gone by. We've had 1-bit, 16-bit, etc., etc., but ultimately I believe the oversampling rate, which you hear less about these days, was the bigger factor. Especially at high frequencies, the more samples you have, the closer you can come to replicating a "smooth" sinusoidal curve. Relatively easy with the longer bass and mid-range frequencies, but the higher you go, the tougher it gets, so the more samples you need.

Today's DAC chips are so fast, it's less of an issue. Only thing faster is analog... vinyl + phono cartridge = infinite sampling...

Q#4 - That tubes generate harmonics is well documented, as are the soothing effects of the harmonics.

Q#5 is interesting... no idea here, but that never stops me so... I'd think that the answer is, no. You computer geeks out there can correct me, if I'm wrong here, but the DAC's at the heart of the matter pretty much either work or they don't. Growing tired is not in their make-up.

Granted that there are other DAC support components in the signal path that can "tire", but I see the impact as no different that an analog pre growing old.

Interesting set of questions...

heiney9

No it doesn't really change over time. I suppose in very rare cases the solid state components in the conversion path could fail, but that's highly unlikely. There is also the contraversy surrounding the supposed "cd rot" that could cause the signal to sound harsh. (I don't personally believe in "cd rot")

Digital harshness is created in two area's.

1. The source material and it's associated recording and mastering techniques.

2. The quality of components and the design of the digital conversion section of any unit that takes digital info and converts it to analog. Areas of concern include; quantization, noise shaping filters, dac chipset, isolation of circuits, word clock inaccuracies (jitter), oversampling, digital noise floor, signal to noise ratio, resolution.

A designer and manufacturer that pays close attention to the above area's will have a superior sounding unit compared to those that don't. However, there is no way to compensate for a poor source recording.

Certainly harshness can be caused by cables, pre's, amps, etc, but I don't consider that "digital harshness". I suppose the cable that connects between a DAC and CDP could potentially be a source for digital harshness, but IMO I'm not completely convinced.

H9

polkatese

appreciate your feedback. The whole subject of tubes-induced digital harshness (Q#4 and 5) is my dilemma. As you know, I have a heavily modded SACD1000, with tube output stage. Over the past few weeks, i noticed an enhanced level of high-freq resolutions that a bit excessive (to my untrained ears), but only on certain albums/recordings. Further investigation did brought an example due to Q#3, Recording quality, but still I wonder about the burn-in/aging factors, having the unit for almost 3 years now.

heiney9

My response was for Solid State stuff. I suppose tubes are always going to have their own character and they certainly can wear out or atleast the tolerance can change over time and in certain conditions.

H9

steveinaz

polkatese wrote:

1. Definition, how would you defined Digital Harshness?
2. Assuming that Digital Harshness can only exist in the signal path, within the constrained and/or realm of CDP/DAC and Pre/Pro, how likely pre/pro be the reason for it?
3. Recording quality - remastered versus recent (10 years or less) - how much of it matters?
4. Introduction of tubes into the chain - softening or coloring the sound, what is the true measure?
5. Lastly, can it develop over time due to changing characteristics/burn-in of tubes, if the CDP is in the chain, thus increasing the likelihood of the presence of Digital Harshness?

1. Glare in the midrange/treble; flat soundstage; listener fatigue
2. Not very likely, unless the pre/pro is known to be hot in the upper freq's
3. Remaster's vary in quality/success of the remake--no hard fast rule
4. Don't understand the question....?
5. Digital harshness varies with the quality of the recording and your components; it's doesn't develope over time, per se, unless you add a component that doesn't do digital very well. Most digital harshness is due to poor recording/engineering and/or a poor source.

polkatese

steveinaz wrote:

4. Don't understand the question....?

I was trying to correlate the relevancy of tube output stage or any tube-related enhancements to the signal path, and how/why/can it be the reason for digital harshness. And, how to measure the effect/impact scientifically.

I know, I think I overANALyzed the subject...:)

John K.

Polkatese, there's no "digital harshness" as such. Any recording can be harsh if it's done poorly, regardless of what format it appears on. T2's discussion in particular points out the inexpert handling of some early CDs 20 or more years ago when the compensation for LP records(unnecessary for digital CDs)was left in, resulting in exaggerated highs. The digital sampling process yields an exact duplicate of the analog waveform and can't result in harshness in and of itself.

F1nut

Another pant load brought to you by none other than John K., owner of not one, but two CD changers. Can you say, sibilance? Yeah, I thought so.

TroyD

The digital sampling process does not and can not yield and exact duplicate of the analog wave form. Slice it any way you want but digital AIN'T analog. It can get close, but no cigar.

Where does he come up with this ****?

BDT

F1nut

Where does he come up with this ****?

Roger Russell and the Axiom forum.

TroyD

John K. wrote:

The digital sampling process yields an exact duplicate of the analog waveform .

I'd LOVE to hear an explanation of this.

BDT

heiney9

John K. wrote:

Polkatese, there's no "digital harshness" as such. The digital sampling process yields an exact duplicate of the analog waveform and can't result in harshness in and of itself.

How long does it take for a transmission of this type to get from Pluto to Earth? You're living in a different world my friend. Completely wrong, not even close.

H9

BobMcG

Your ears and the connecting gray matter does change over time....:p

speakergeek

OT: But what do you guys think about the new digital receivers (panasonic XR55 and JVC D702B)? I heard a panasonic and didn't really like it. There seemed to be a real absence of warmth to the sound. For lack of a better term, it seemed sterile/harsh. Is that a product of the digital technology?

heiney9

speakergeek wrote:

OT: But what do you guys think about the new digital receivers (panasonic XR55 and JVC D702B)? I heard a panasonic and didn't really like it. There seemed to be a real absence of warmth to the sound. For lack of a better term, it seemed sterile/harsh. Is that a product of the digital technology?

Well first of all the term "digital receiver" is misnomer. There is nothing digital about it. It refers to the type (class) of amplification used.

D Does NOT Equal Digital

Class D amplifiers are not digital in the true sense. They are not driven directly by coherent binary data. They do act digitally in that the output drivers operate either in the fully ON-region or fully OFF-region. Think of Class D amps as being similar to a switch-mode power supply, but with audio signals modulating the switching action.

A switch-mode power supply uses pulse-width modulation (PWM) to control the on/off duty cycle of the power switching transistor(s) providing power to a load. The efficiency is high because there is little voltage drop across the switch transistor during conduction. This means very low power dissipation in the switch while virtually all the power is transferred to the load. During the OFF period, there is essentially zero current flow. The quality and speed of MOSFET (metal oxide semiconductor field effect transistor) devices has led to compact, efficient, high frequency power supplies. Switch-mode power supplies are more efficient at high frequencies. At higher operating frequencies, components may become smaller and the power supply becomes very compact for the power delivered. In addition, the output filter components may be much smaller. Today, switching frequencies over 1 MHz are not uncommon. But, as you probably know, switch-mode supplies generate considerable noise.

What does this have to do with audio? Audio signals can be used to modulate a PWM system to create a high power audio amplifier at nominal voltages using small components. Class D audio utilizes a fixed, high frequency carrier having pulses that vary in width based on signal amplitude. Class D amplifiers reach efficiencies as high as 90%. This is of great importance to portable applications relying on battery power. Class D portable, battery-powered audio gear may have battery life extended by 2.5 times or more.

Saving electrical power is now becoming a concern. Equipment utilizing Class D systems save significant operating power. For equipment having a limited power budget or available voltage range, Class D can get the job done without redesigning power supplies for more signal headroom.

I've not auditioned one, but I'm old school and everything I've read about the design I doubt I'd like it. But I'll never know for sure until I audition one.

H9

speakergeek

Thanks for the information. I figured they had to do with energy conservation. Probably stemming from the darned Kyoto accord agreement. I could tell a difference sound quality wise though.

John K.

This is basic stuff; the essential factor in the digital sampling process stated as simply as possible. For a more detailed explanation see the signal reconstruction section of Dr. Lesurf's guide which was originally used as introductory material for his electronics and physics students.

F1nut

Another pile of crapola. If the digital sampling process for redbook captured the analog source perfectly there wouldn't be any advantage to SACD or DVD-A.

If you listened with your ears and didn't rely on something someone wrote, you'd know the difference. That is basic stuff!

Tour2ma

So now you're saying that SACD captures "the analog source perfectly"?

George Grand

Nothing captures the "analog source" perfectly. Not digital, not analog. You can't capture an exact recording of my voice on digital, vinyl, or tape. Limits are everywhere, and if I enjoy my rig, or you enjoy yours, what the hell else could matter?

Tour2ma

Point taken... tend to talk vinyl vs. digital, but 15 ips magnetic tape is really the only uncompromised analog source.

But even at 15 ips, we all sound different to ourselves when recorded and played back...

candyliquor35m

Are you letting your tubes warm up about 30 minutes? Mine sounded harsh today but that was after listening to mostly vinyl the past few months. After a couple of hours, my ears adjusted or the tubes warmed up nicely . My elephant ears seem to help the harshness a little but they aren't very practical.

http://www.polkaudio.com/forums/showthread.php?t=29641

George Grand

We never sound realistic to ourselves when played a recording of our own voice because the only time we "hear" ourselves live is when we speak. When we speak, we hear the vibration and conductivity in our own jawbone. Others don't hear that.

That is not the point I was trying to make though. I was just using the human voice as the simplest example of something that can be recorded. Then again, the human voice is the thing we hear the most, making it the easiest thing for us to critique.

F1nut

That's not what I said, Bruce.

organ

Tour2ma wrote:

I think #3 is key. Not that mixes can't be garbage today as all audio engineers are not created equal, but hopefully you have to go back more like 20 years to find true harshness.

Many early CD's were rushed into production to cash in on the latest "craze". Many labels were in such a rush that they did not even bother to remove the RIAA equalization built into the master tapes. RIAA boosts highs and reduces lows for mechanical reasons during vinyl playback. All phono pre's compenstate producing a flat signal.

Enter the CDP sans RIAA compensation... and the "harsh" CD was born. Exaggerated highs = shrill and hollowed out lows = no wamth... take this as my definition, answering Q#1, if you like. There can be more to remastering than removal of the RIAA equalization, but it's a key element.

On your Q#2...
Again I think it's more likely to be DAC related in years gone by. We've had 1-bit, 16-bit, etc., etc., but ultimately I believe the oversampling rate, which you hear less about these days, was the bigger factor. Especially at high frequencies, the more samples you have, the closer you can come to replicating a "smooth" sinusoidal curve. Relatively easy with the longer bass and mid-range frequencies, but the higher you go, the tougher it gets, so the more samples you need.

Today's DAC chips are so fast, it's less of an issue. Only thing faster is analog... vinyl + phono cartridge = infinite sampling...

Q#4 - That tubes generate harmonics is well documented, as are the soothing effects of the harmonics.

Q#5 is interesting... no idea here, but that never stops me so... I'd think that the answer is, no. You computer geeks out there can correct me, if I'm wrong here, but the DAC's at the heart of the matter pretty much either work or they don't. Growing tired is not in their make-up.

Granted that there are other DAC support components in the signal path that can "tire", but I see the impact as no different that an analog pre growing old.

Interesting set of questions...

WHOA! Very informative post there, Bruce. Makes perfect sense to me. You sure you're not teaching physics and electronics part time in a university?;)

Tour2ma

No, but I did sleep at a Holiday Inn Express last night... Thanks...

Jesse,
Honestly, I did not think that's what you meant.

GG,
Is it live or is it Memorex?