The optimum H2 amount may somewhat be related to loudspeaker being used. I hope your issue gets resolved soon and be able to tinker with the new entertainment gadget.
Pretty funny that when Bob Katz's article appeared a few months ago, showing THIS EXACT H2 phenomenon, complete with a free circuit schematic to insert a user-variable amount of H2 (including bypass == 0.000000000% extra H2) nobody on this thread except John Curl, made any remarks at all. What could that mean? Hmmm.
Link to schematic?
Also, might be worth pointing out that Sabre dacs have H2 and H3 harmonic distortion compensation registers. They could be used to increase H2 if desired.
Means to me that Just build anything and enjoy the music if you like it.
Its not what Hi-End is though.
Its not accurate. Poor performance circuits can be bought as low-to mid-fi equipment from appliance stores. Or old tube gear. .... Its harmonic distortion has always been called spacious and deep etc. Just the effect of harmonic distortion being audible.
Some headphone amps have some 2H etc on purpose for the effect.
THx-RNMarsh
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http://img2.tapuz.co.il/forums/1_133166698.pdf
Demian has linked to it (no schematic in the article, adjusting bias on a nuvistor amplifying stage)
John Curl's Blowtorch preamplifier part III
The Sound of the Machine
There is also this product : “Apply transfer functions like tube (2H) and tape (3H)”
Parks Audio
It happens I am cleaning up my JLH1969 amp
George
Most connector issues are provoked by environmental factors in conjunction with dissimilar metal junctions. High humidity accelerates the degrading of the interface, nickel will passivate fairly rapidly in high humidity and form an insulating layer. One will note that only cheap RCA connectors use plain nickel as the contact material for these reasons. Most gold plating on connectors is cosmetic and not done with either a stable base plate of nickel or the gold is impure. Either way, the gold can wipe off even on the first insertion and result in nickel to nickel or other metal contact.
The major symptom we experienced with hundreds of BNC and XLR connectors in our systems was rising resistance. If the connector was disturbed the contact patch would move, potentially onto an oxidized place. if left unaddressed it could progress to a state where the signal dropped out at low levels and the signal peaks would arc through the oxide layers and give a crackling noise correlated with the signal peaks. There is a continuum of effects between these two extremes.
Connnector problems with unbalanced signal transport, especially using RCAs can induce strong common-mode chassis to chassis flow with attendant noise susceptability. The same is possible with balanced connectors, although XLRs are usually more reliable than RCAs which makes the problem less frequent.
In my experience when using even quality BNC connectors, the heavily gold plated center pin retains low resistance over time, whereas the nickel to nickel shell contact can degrade. The best quality BNCs feature gold plated shell contact areas as well. We had greatly extended maintenance intervals by cleaning with Freon TF, then applying a light coating of Cramolin Blue lubricant/sealer. For XLRs we settled on gold Neutrik XLRs which seemed to have very stable resistance over time, even compared with the workhorse silver-plated Switchcrafts. In the intervening years Switchcraft has also come out with a line of gold contact XLRs and RCAs which are high quality. Similar cleaning and preservation techniques work well with other connector types.
If one was to attempt to quantify this issue, given the multiplicity of contact metals, plating processes and failure modes, the possible problem matrix is large. It would take many controlled tests in an environmental chamber to give reliable and reproducable results. Fortunately this issue has been well researched and reported for 100 years, notably by Bell Labs with the paper: "A Field Study of Seperable Connectors" which requires an IEEE login to view at:
A Field Study of the Electrical Performance of Separable Connectors - IEEE Journals & Magazine
Or the more accessible paper hosted on the TE website at http://www.te.com/documentation/whitepapers/pdf/p351-93.pdf which deals more with tin and gold plated contacts as found in multi-contact connectors, and there is a lot of other information to be found online as well.
Howie
I think he had to use some better driver/speaker for his test. They are far below SE tube amps, re distortion.
Attachments
Thanks Pavel.
For completeness, here is an old article which deals with the distortion, taking into account the behaviour under dynamic conditions, which gives the psychoacoustic effect of "fuller sound"
Tubes versus Transistors - Is There An Audible Difference? : Russell O. Hamm : Free Download, Borrow, and Streaming : Internet Archive
Howie, thanks for the pdf link and for sharing experience.
George
For completeness, here is an old article which deals with the distortion, taking into account the behaviour under dynamic conditions, which gives the psychoacoustic effect of "fuller sound"
Tubes versus Transistors - Is There An Audible Difference? : Russell O. Hamm : Free Download, Borrow, and Streaming : Internet Archive
Howie, thanks for the pdf link and for sharing experience.
George
Attachments
Thank you very much Mr. Hoyt, very generous of you. Most invaluable experience sharing complete with practical case.
Perhaps so Mr. Macura, but it is also plausible that a wide range high efficiency driver showing distortion characteristic acceptable to you was simply not available, unpopular or exorbitantly priced at the time of his measurement.
Currently I am breadboarding a low to medium DF 9W SE hybrid 801A DHT Amp with adjustable (through feedback) ~0.01-0.9% THD. With all due respect, kindly suggest if you know of a reasonably priced wideband high efficiency driver with distortion characteristic somewhat not objectionable to you.
The interesting point raised by Eduardo de Lima is that total distortion at listener position matters. I only found somewhat related efforts made public by Nelson Pass and Bob Katz on audible effects of 2H, but there was no definitive correlation yet of said effects to the total sum of distortion arriving at the listener position
It is confusing for a non audio professional like me when a system with lower measured total distortion across audio frequency (due to cancellation) is to be avoided, deemed not accurate or illusion. Perhaps some of you in the know could share something so people like me could avoid pitfalls. wild goose chasing and bottomless money pits. Thank you.
Thanks but things are a bit in chaos for me right now. IIRC Schoeps uses this trick to trim the seconds of the FET phase splitter in their mics to 0.
Depends on what the definition of H-End should be?
Should it be the most accurate output to the input?
Or should it be the most believable illusion produced?
Or is it something else?
If we take accuracy as the correct criteria, we have to specify all the realistic conditions that are necessary to evaluate i.e not just static signals. It would seem that the best methodology is a very accurate difference track using music as the input signal, followed by a real analysis of the residual spectrum, using real & modern understandings of psychoacoustics, not just simplistic considerations about thresholds, masking, etc. (I believe KSTR gave his approach to this analysis before which didn't involve the Diffmaker software as he considered it not up to the task). As the Hamm paper suggests, the real world dynamic signals in the recording & playback chain need careful consideration.
If we consider the most believable illusion produced as the correct criteria & we study & analyse the factors that achieve this, we may learn some important factors. We often see people dismiss this as "some people like pleasing distortions" but, to my mind we are missing the fact that it is our auditory perception telling us that it is receiving signals that better match its criteria for judging the realism of sounds - in other words, auditory processing is an analysis engine & one of its initial analysis results is 'how close is this sonic illusion to what I would hear in the real world sound(scape)' Dismissing it as just a 'pleasing distortion' seems blinkered, IMO.
We already know that the whole recording/playback system cannot capture the full sonic experience so we are dealing with making the best illusion from this limited reproduction. So raw accuracy may be exposing the limitations of this chain & certain added distortions may help to fill in (or perhaps mask) these limitations?
So-called 'High end' is almost always expensive, so it should be whatever the customer wants it to be. Market forces will ensure this.
Your points about accuracy vs. most believable illusion may apply more to attempts at hi-fi. However, it needs to be said that you can only judge an acoustic illusion if you have heard the acoustic real thing. This rules out most modern music (which never existed as a purely acoustic sound to be simply recorded) and some modern listeners (who rarely attend a concert).
Personally I don't buy the 'a little added distortion makes it sound more like the real thing' argument. For that to happen you would need to know what distortions were added in the reproduction chain and seek to undo them. However, I come from the 'accuracy' camp so I would say that, wouldn't I?
Curiuously, many people in the 'illusion' camp like to talk as though they are in the 'accuracy' camp: they claim that their preferred system has lower (unspecified, unmeasured) distortion even though it has higher (specified, measurable, sometimes audible) distortion than a system designed using 'conventional engineering'.
Your points about accuracy vs. most believable illusion may apply more to attempts at hi-fi. However, it needs to be said that you can only judge an acoustic illusion if you have heard the acoustic real thing. This rules out most modern music (which never existed as a purely acoustic sound to be simply recorded) and some modern listeners (who rarely attend a concert).
Personally I don't buy the 'a little added distortion makes it sound more like the real thing' argument. For that to happen you would need to know what distortions were added in the reproduction chain and seek to undo them. However, I come from the 'accuracy' camp so I would say that, wouldn't I?
Curiuously, many people in the 'illusion' camp like to talk as though they are in the 'accuracy' camp: they claim that their preferred system has lower (unspecified, unmeasured) distortion even though it has higher (specified, measurable, sometimes audible) distortion than a system designed using 'conventional engineering'.
Hi mmerrill99,
Accuracy is the only metric that makes sense. Otherwise it devolves into a bunch of poor designs that have "good distortion" added. Only a fool treads down that path.
Steady state signals are enough. But they can be gated on and off too. "Real music" doesn't reveal anything new to the test equipment, but then any good designer also listens to the design as well. That would seem to have all your basses covered.
If you are proposing that we no longer take measurements and consider them with as much weight as we currently do, may as well take a time machine back to the dark ages. There you will find nothing but live music.
-Chris
Accuracy is the only metric that makes sense. Otherwise it devolves into a bunch of poor designs that have "good distortion" added. Only a fool treads down that path.
Steady state signals are enough. But they can be gated on and off too. "Real music" doesn't reveal anything new to the test equipment, but then any good designer also listens to the design as well. That would seem to have all your basses covered.
If you are proposing that we no longer take measurements and consider them with as much weight as we currently do, may as well take a time machine back to the dark ages. There you will find nothing but live music.
-Chris
There is the idea that the more you listen to live music and real world sounds generally the greater your ability to perceive the reproduced sound as more realistic. This should be regularly refreshed
Exactly...X100
In addition, with profits from selling physical media in the toilet, many if not most artists make their living wage through live shows and merchandise sold at them. Without the artists, our business/hobby is redundant...support your favorite artists and your ability to enjoy them at home at the same time!
Howie
Agree with DF96 that added distortion is probably not a good thing in most cases.
First of all, when Bob Katz talks about adding 2H to fix a recording during mastering, it is a bandaid fix because the mix came in with problems such as excess high order distortion. Bob is trying to see if he can fix it rather than return it for a remix. Once Bob has applied the treatment, it is done and the record is ready to be listened to on a low distortion system. That's why it was done at mastering, so users at home don't have to fix the recording themselves. Most competent mastering engineers have ways of adding 2H if needed, such as can easily be done with Crane Song HEDD.
Secondly, because I have Crane Song HEDD and an ESS dac with access to the harmonic compensation registers, I have had a chance to turn the knobs and listen to the effects of added 2H, 3H, triode, and pentode type distortion profiles. To me, no decently mastered recording sounds better with more distortion. If it was needed, it was already done before I got the record.
If there is a problem with someone's system that sounds like some distortion would make it sound better, probably it would be better to figure out what is making the system sound like it needs that extra distortion and fix the problem that is the underlying cause. Adding more distortion to help mask other distortion in a system is never the best sounding fix, IMHO.
First of all, when Bob Katz talks about adding 2H to fix a recording during mastering, it is a bandaid fix because the mix came in with problems such as excess high order distortion. Bob is trying to see if he can fix it rather than return it for a remix. Once Bob has applied the treatment, it is done and the record is ready to be listened to on a low distortion system. That's why it was done at mastering, so users at home don't have to fix the recording themselves. Most competent mastering engineers have ways of adding 2H if needed, such as can easily be done with Crane Song HEDD.
Secondly, because I have Crane Song HEDD and an ESS dac with access to the harmonic compensation registers, I have had a chance to turn the knobs and listen to the effects of added 2H, 3H, triode, and pentode type distortion profiles. To me, no decently mastered recording sounds better with more distortion. If it was needed, it was already done before I got the record.
If there is a problem with someone's system that sounds like some distortion would make it sound better, probably it would be better to figure out what is making the system sound like it needs that extra distortion and fix the problem that is the underlying cause. Adding more distortion to help mask other distortion in a system is never the best sounding fix, IMHO.
If people have their preferences about playback and are open about it (maybe he/she just wants a "house sound", whether it sounds "better" or not), I can't see what's wrong with it. Just do what you say you're trying to do! (you in the general sense)
I mean, I design for various different goals (and generally arbitray), so whatever brings you joy and doesn't require rewriting physics to justify.
As far as "live" music, how much are we able to use that as some sort of reference? So much of its experiential, and the sound changes depending on where you're sitting anyhow. I just find the whole "accuracy" thing a bit of a stretch, even if my general tendency is towards "let's hear what the mixing engineer meant" for playback.
I mean, I design for various different goals (and generally arbitray), so whatever brings you joy and doesn't require rewriting physics to justify.
As far as "live" music, how much are we able to use that as some sort of reference? So much of its experiential, and the sound changes depending on where you're sitting anyhow. I just find the whole "accuracy" thing a bit of a stretch, even if my general tendency is towards "let's hear what the mixing engineer meant" for playback.
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