What annoys me today in marketing and media that too often today then talking on hi-fi, science is replaced by bizarre belief structures and marketing fluff, leading to a decades-long stagnation of the audiophile domain. Science makes progress, pseudo-science doesn’t. Hi-fi world is filled by pseudoscience, dogma and fruitloopery to the extent that it resembles a fundamentalist religion. Loudspeaker performance hasn’t tangibly improved in forty years and vast sums are spent addressing the wrong problems.
Business for Engineers: Marketers Lie article points tout that marketing tells lies — falsehoods — things that serve to convey a false impression. Marketing’s purpose is to determining how the product will be branded, positioned, and sold. It seems that there too many snake oil rubbish products marketed in the name of hifi. It is irritating to watch the stupid people in the world be fooled.
In EEVblog #29 – Audiophile Audiophoolery video David L. Jones (from EEVBlog) cuts loose on the Golden Ear Audiophiles and all their Audiophoolery snake oil rubbish. The information presented in Dave’s unique non-scripted overly enthusiastic style! He’s an enthusiastic chap, but couldn’t agree more with many of the opinions he expressed: Directional cables, thousand dollar IEC power cables, and all that rubbish. Monster Cable gets mostered. Note what he says right at the end: “If you pay ridiculous money for these cable you will hear a difference, but don’t expect your friends to”. If you want to believe, you will.
My points on hifi-nonsense:
One of the tenets of audiophile systems is that they are assembled from components, allegedly so that the user can “choose” the best combination. This is pretty largely a myth. The main advantage of component systems is that the dealer can sell ridiculously expensive cables, hand-knitted by Peruvian virgins and soaked in snake oil, to connect it all up. Say goodbye to the noughties: Yesterday’s hi-fi biz is BUSTED, bro article asks are the days of floorstanders and separates numbered? If traditional two-channel audio does have a future, then it could be as the preserve of high resolution audio. Sony has taken the industry lead in High-Res Audio.
HIFI Cable Humbug and Snake oil etc. blog posting rightly points out that there is too much emphasis placed on spending huge sums of money on HIFI cables. Most of what is written about this subject is complete tripe. HIFI magazines promote myths about the benefits of all sorts of equipment. I am as amazed as the writer that that so called audiophiles and HIFI journalists can be fooled into thinking that very expensive speaker cables etc. improve performance. I generally agree – most of this expensive interconnect cable stuff is just plain overpriced.
I can agree that in analogue interconnect cables there are few cases where better cables can really result in cleaner sound, but usually getting any noticeable difference needs that the one you compare with was very bad yo start with (clearly too thin speaker wires with resistance, interconnect that picks interference etc..) or the equipment in the systems are so that they are overly-sensitive to cable characteristics (generally bad equipment designs can make for example cable capacitance affect 100 times or more than it should). Definitely too much snake oil. Good solid engineering is all that is required (like keep LCR low, Teflon or other good insulation, shielding if required, proper gauge for application and the distance traveled). Geometry is a factor but not in the same sense these yahoos preach and deceive.
In digital interconnect cables story is different than on those analogue interconnect cables. Generally in digital interconnect cables the communication either works, does not work or sometimes work unreliably. The digital cable either gets the bits to the other end or not, it does not magically alter the sound that goes through the cable. You need to have active electronics like digital signal processor to change the tone of the audio signal traveling on the digital cable, cable will just not do that.
But this digital interconnect cables characteristics has not stopped hifi marketers to make very expensive cable products that are marketed with unbelievable claims. Ethernet has come to audio world, so there are hifi Ethernet cables. How about 500 dollar Ethernet cable? That’s ridiculous. And it’s only 1.5 meters. Then how about $10,000 audiophile ethernet cable? Bias your dielectrics with the Dielectric-Bias ethernet cable from AudioQuest: “When insulation is unbiased, it slows down parts of the signal differently, a big problem for very time-sensitive multi-octave audio.” I see this as complete marketing crap speak. It seems that they’re made for gullible idiots. No professional would EVER waste money on those cables. Audioquest even produces iPhone sync cables in similar price ranges.
HIFI Cable insulators/supports (expensive blocks that keep cables few centimeters off the floor) are a product category I don’t get. They typically claim to offer incredible performance as well as appealing appearance. Conventional cable isolation theory holds that optimal cable performance can be achieved by elevating cables from the floor in an attempt to control vibrations and manage static fields. Typical cable elevators are made from electrically insulating materials such as wood, glass, plastic or ceramics. Most of these products claim superior performance based upon the materials or methods of elevation. I don’t get those claims.
Along with green magic markers on CDs and audio bricks is another item called the wire conditioner. The claim is that unused wires do not sound the same as wires that have been used for a period of time. I don’t get this product category. And I don’t believe claims in the line like “Natural Quartz crystals along with proprietary materials cause a molecular restructuring of the media, which reduces stress, and significantly improves its mechanical, acoustic, electric, and optical characteristics.” All sounds like just pure marketing with no real benefits.
CD no evil, hear no evil. But the key thing about the CD was that it represented an obvious leap from earlier recording media that simply weren’t good enough for delivery of post-produced material to the consumer to one that was. Once you have made that leap, there is no requirement to go further. The 16 bits of CD were effectively extended to 18 bits by the development of noise shaping, which allows over 100dB signal to noise ratio. That falls a bit short of the 140dB maximum range of human hearing, but that has never been a real goal. If you improve the digital media, the sound quality limiting problem became the transducers; the headphones and the speakers.
We need to talk about SPEAKERS: Soz, ‘audiophiles’, only IT will break the sound barrier article says that today’s loudspeakers are nowhere near as good as they could be, due in no small measure to the presence of “traditional” audiophile products. that today’s loudspeakers are nowhere near as good as they could be, due in no small measure to the presence of “traditional” audiophile products. I can agree with this. Loudspeaker performance hasn’t tangibly improved in forty years and vast sums are spent addressing the wrong problems.
We need to talk about SPEAKERS: Soz, ‘audiophiles’, only IT will break the sound barrier article makes good points on design, DSPs and the debunking of traditional hi-fi. Science makes progress, pseudo-science doesn’t. Legacy loudspeakers are omni-directional at low frequencies, but as frequency rises, the radiation becomes more directional until at the highest frequencies the sound only emerges directly forwards. Thus to enjoy the full frequency range, the listener has to sit in the so-called sweet spot. As a result legacy loudspeakers with sweet spots need extensive room treatment to soak up the deficient off-axis sound. New tools that can change speaker system designs in the future are omni-directional speakers and DSP-based room correction. It’s a scenario ripe for “disruption”.
Computers have become an integrated part of many audio setups. Back in the day integrated audio solutions in PCs had trouble earning respect. Ode To Sound Blaster: Are Discrete Audio Cards Still Worth the Investment? posting tells that it’s been 25 years since the first Sound Blaster card was introduced (a pretty remarkable feat considering the diminished reliance on discrete audio in PCs) and many enthusiasts still consider a sound card an essential piece to the PC building puzzle. It seems that in general onboard sound is finally “Good Enough”, and has been “Good Enough” for a long time now. For most users it is hard to justify the high price of special sound card on PC anymore. There are still some PCs with bad sound hardware on motherboard and buttload of cheap USB adapters with very poor performance. However, what if you want the best sound possible, the lowest noise possible, and don’t really game or use the various audio enhancements? You just want a plain-vanilla sound card, but with the highest quality audio (products typically made for music makers). You can find some really good USB solutions that will blow on-board audio out of the water for about $100 or so.
Although solid-state technology overwhelmingly dominates today’s world of electronics, vacuum tubes are holding out in two small but vibrant areas. Some people like the sound of tubes. The Cool Sound of Tubes article says that a commercially viable number of people find that they prefer the sound produced by tubed equipment in three areas: musical-instrument (MI) amplifiers (mainly guitar amps), some processing devices used in recording studios, and a small but growing percentage of high-fidelity equipment at the high end of the audiophile market. Keep those filaments lit, Design your own Vacuum Tube Audio Equipment article claims that vacuum tubes do sound better than transistors (before you hate in the comments check out this scholarly article on the topic). The difficulty is cost; tube gear is very expensive because it uses lots of copper, iron, often point-to-point wired by hand, and requires a heavy metal chassis to support all of these parts. With this high cost and relative simplicity of circuitry (compared to modern electronics) comes good justification for building your own gear. Maybe this is one of the last frontiers of do-it-yourself that is actually worth doing.
1,575 Comments
Tomi Engdahl says:
Speakers>Amp>cd or record player, in this order, speakers are most importent, normal good cables for speakers and interlinks, AC is not importent, raisers and pads and other crap is totally useless.
Tomi Engdahl says:
I think you first need to understand why you think fuses might (even possibly) make a difference.
Similar items like exotic mains cables have been thoroughly tested vs scientific criteria for audio transparency (testable limits for everything that matters to human detectable audio quality). Results are right there for you to find, and are utterly convincing.
My guidance? The majority of audio enhancement products are deliberate nonsense.
One more point. Trusting your ears to judge whether X is better that Y is an invalid technique. You cannot judge that unless the test is double blind, and that isn’t easy to set up. This is proven science.
Tomi Engdahl says:
Psychoacoustics, if your mind thinks it should sound better you’ll hear it that way hence the double blind, it’s not saying anything about your ears or the way you hear but everyone’s mind acts this way, you may of heard confirmation bias, if you’ve just spent say 2k you’re actively looking for justification & your mind will find it even if it isn’t there
I would go so far as to say “You WILL actually perceive a difference in alignment with your expectations (if you do not double blind test). The only problem is that the difference is not real.”
This truth is very uncomfortable for many folks.
Interestingly, it actually implies that if you show your friends what your system LOOKS like, that will naturally be as important to their judgment of the system’s quality than the way it sounds!
Tomi Engdahl says:
Where’s the fun in doing critical listening sessions, trying to force yourself to hear a difference to justify spending an extorionate amount of money on some fine snake oil?
The fun part should ultimately be listening to the music not critiqueing your equipment.
Tomi Engdahl says:
Mark Holden, there is not a fuse in existence that will blow quicker than a transistor taken out of it’s safe operating area.
Fuses in amplifiers stop fires, that is about it.
Tomi Engdahl says:
The mains fuse must be equal to or lower than the current rating of the mains cable. There is no provision in the wiring regulations for audiophiles believing that this does not apply to them. If increasing the fuse rating or changing it to something exotic does make a difference, put whatever is on the other end of the cable back in the box and send it back to the manufacturer with a demand for either a refund or a replacement with a competently designed power supply.
Tomi Engdahl says:
Whoever designed the circuit used a fuse of a certain value for a sound reason, to provide a calculated degree of protection for the following circuitry. The only thing achieved by fitting a higher rated fuse is to increase the risk of expensive damage if a fault occurs.
Tomi Engdahl says:
The fuse specified by the manufacturer should always be used. That is, the specified current rating and either “slow blow” or “quick blow” as specified. Using a lower value, if it doesn’t blow, won’t do any harm, but using a higher value is never advisable.
Tomi Engdahl says:
The quickest way to know if the fuse makes an audible difference is desolder the power cord from fuse holder and bypass the fuse and holder. Probably not a good idea for long term, but it will satisfy your curiosity. I would recommend undoing this after your listening tests.
Tomi Engdahl says:
Fuses have a specific function – save lives and equipment. I would never mess with this critical safety feature. Whether or not the fuse is audible is another issue, A very controlled test would be necessary. I really doubt that the audiophool would be willing to conduct any type of realistic test. That is not to say that there would be no difference if everything else was in line!
Tomi Engdahl says:
In an output signal path, fused speaker lines, a slow-blow or delayed fuse may actually make a small difference in the sound versus a fast-blow fuse. Depending on musical content, switching from a slow fuse to a fast may also require increasing the current rating to allow the expected peak surges from not blowing the fast acting fuse prematurely.
A fuse on the mains side or in the power supply is a safety device however, and is not expected to affect sound quality unless there is a serious design flaw in the amplifier.
Tomi Engdahl says:
It is absolutely possible for a fuse to affect sound quality. But any equipment whose performance is subject to the “quality” of a fuse is not worth my time and money. I prefer well-designed electronics.
If you really want to test if fuses make a difference, here is a simple test. Get a high current on off switch, wire it in parallel with your fuse using appropriate size wire.. Insulate everything properly. While listening have a friend turn the switch on and off such that you can’t see or hear the switch change. If you can properly tell when the switch is on, bypassing the fuse, more than 50% then you may be on to something. I’m betting you won’t hear any difference. But do NOT leave the switch connected, except for testing. As others have said,, the fuse is there to keep your house from burning.
https://www.facebook.com/groups/DIYAudio/permalink/6665922443473545/
Tomi Engdahl says:
Andrew Fisher what mechanism makes music travel along the surface?
skin effect. Higher frequency travels closer to the skin. Its not really a factor in choosing solid or stranded though.
cross sectional area is where it’s at.
Solid wire has a higher resistance at higher frequencies, due to surface effect… but I don’t know if it’s a measurable or perceptible difference at audio frequencies. Anyone?
it’s not. Skin depth at 20kHz in copper is nearly a millimeter. That’s nearly twice the radius of 18ga wire.
There’s no sound difference or resistance difference between solid and strand. You can run what you want with confidence.
FWIW, I use solid core in crossovers as it’s easier to solder, but generally run strand internally from the crossover to the drivers.
Solid core ( single strand) has nothing to do in a vibrational environment like a higher powered bass speaker. THere’s absolutely no logic behind being easier to wire with solid core… Flexible wire is the stuff to go to.. skin effect in audio is mainly BS, as so much else associated with “HiEnd Audio”. Cross section is really the only parameter that matters – albeit with some nototiously strange amplifiers and even worse speakers, other cable parameters of inductance and capacitance may be important… it’s really all up to you.. If you want to believe in the BS served by “HiEnd” cable producers, and are prepared to pay 10.000 $/foot… be my guest…
Stranded wire is better when you need it to be flexible. Solid wire is for fixed wiring where no movement is involved.
https://www.facebook.com/groups/DIYAudio/permalink/6704929212906201/
Tomi Engdahl says:
EU bureaucratic does not like hifi fools in going bananas. Use of normal banana plug for hifi speaker connections is banned because it fits too easily to European mains outlets with shocking results.
Tomi Engdahl says:
The usual problems are lack of clearance (on both circuit board and inside transformer) and use of wrong type capacitor from mains side to low voltage side.
Tomi Engdahl says:
Other companies have research and development, behringer has rip-off and duplicate. It’s all r&d
Tomi Engdahl says:
Unify Sound, Creation, Recording and Reproduction
https://www.youtube.com/watch?v=Eitrv4L1v5A
The video discusses the challenge of unifying the various elements of instruments, sound reinforcement and playback to enhance engineering and sound system design. The speaker emphasizes the importance of understanding the complexities and nuances of sound capture and reproduction, including mic placement and the use of multiple perspectives. They explain the downsides of sending the same sound to multiple speakers, which creates comb filtering, interference, and summation issues. Techniques for capturing room sound during music recordings are also discussed, along with alternative approaches such as using close mic’ing and adding realistic-sounding reverbs in post-production. The speaker concludes with a demonstration of a Columbia graphophone from 1890 and talks about the mechanisms of horns as acoustic transformers. The video ends with a musical segment featuring the Death Fighter 2000 or DB.
Tomi Engdahl says:
https://www.facebook.com/groups/DIYAudio/permalink/6688138731251916/
I have a toroidal transformer, in a cyrus psx, that sometimes mechanically hums when idle. I think it’s related to a DC component on the mains (UK 230V 50hz). I’ve read about DC blocker circuits to solve this. Anybody got any experience to share. Good, bad, or ugly?
It depends on the reason for humming. I have a dc blocker, designed the way rod elliot says (sound-au above). The transformer still ums, but not as badly. I think if you are running 50/60 Hz through a coil of wires, and they are not completely mechanically stable, it’s likely they will hum.
If you really got DC in your AC, a DC-blocker should be the tool. I have no own experience with such a thing, but if I would have this problem, I’d google and would try to find out everything about DC-blockers, instead of asking at FB. You cannot know how valuable the Information is that you get here.
Jochen Burkart I’ve already done that, and gone into the theory in some detail. That’s why I’m asking this group about your practical experience.
Rod Lancaster I don’t expect to have less DC on my mains than others, but I never experienced this problem. Just a short hum on the inrush for max. 2sec. . All I use is a lot of µF and a cap multiplier. I use 200VAC, 25-0-25V toroids.
If the huming is not constant in level and varies with time, it is most probably DC. Any DC filter will cure it, but many filters other sh*t on the mains. A lot of the rectifier based design display sloppy design with no decoupling of the diode open gate noise. Check before purchase. So you do not replace the DC with ripple and potential resonances.
I use a DC blocker in all my DIY projects. Many commercial companies in the audio sector have installed a DC blocker. The Blocker works very well. Each manufacturer does it a little differently, but it’s basically a few diodes and capacitors.
I would also look at the AC waveform. Years ago I had luxtrol dimmers that are wound like a toroidial transformer that would hum like crazy and it was caused by equipment in the building that had switching power supplies that was messing up the waveform. But it’s probably just an old transformer getting loose windings
I used to love toroids. But after many years I came to dislike them. Come on, a mains transformer which has problems when connected to mains? Gimme a break. Not so sexy but robust as hell: gimme an EI transformer any day of the week. Assimmetric Mains is a reality of Life.
There is a warning with toroids about their mounting associated with creating a mounting electrical circuit between the top and bottom through the middle of the donut ie if the case is earthed with the tr mounted to it then you add an earth to the central mounting screw you effectively introduce a near zero ohm single winding which will cause the transformer loading issues (AKA noise vibration issues plus overheating).
John Widder Thing is torodials display quite sparse headroom in magnetic flow, hence being more sensitive to core saturation. On top of that, the conventional torodial is inferior as ripple prevention due to stray between primary and secondaries. Even though some brands claim audiophile torodials you rarely see electrostatic shields between windings to limit stray high frequency noise from entering. I am not very impressed by the majority of hifi brands when it comes to well known and verified old school preventive measures of keeping audio silent, even if the component quality is vastly improved nowadays. One example is the praised 85 degree el cap which in reality is inferior to the latter 105 and 125 degree caps with far better noise decoupling already just after the noisy rectifiers, that commonly is selected from cheap column when a schottky diode would be far better to not create more noise than already present … But I thank them, they leave plenty of space for my noise killing external devices …
I would go with a mechanical issue ie squished neoprene washers which may or may not be fitted to the transformer mounting. Other thing to check is the case lid mounting screws are seated correctly and tight-ish
Not my personal experience, but the guy who runs this site knows what he’s doing:
https://sound-au.com/articles/xfmr-dc.htm
Richard Becke Thanks . Already had a good read of that. Its very comprehensive. An excellent resource.
Richard Becke , yes great article. I don’t know how anything that half waves on the mains or creates DC would be allowed to be sold. I was surprised by the small value of DC required to cause a problem, but it seems only to be with quite large toroids.
Tomi Engdahl says:
Interesting thread > https://pinkfishmedia.net/forum/threads/whats-the-best-diy-dc-blocker-circuit.261765/
https://sjostromaudio.com/pages/index.php/hifi-projects/187-dct03-the-dc-trap-high-end-style-heavy-duty
Tomi Engdahl says:
https://www.facebook.com/groups/DIYAudio/permalink/6733404980058624/
I am a believer of adopting Current Drive for loudspeaker. I have been using this for over 2 years now and so far are happy about it.
I got a lot of info from this:
https://www.current-drive.info/
Starting with the loudspeaker. I use a Fostex FE168 sigma (old version) which I bought 20 years ago. For current drive use, a sealed box is preferred. I am a lazy guy and have a very shallow pocket, I have to build it in the cheapest way. The driver is mounted on a chip board cut from some scrapped cabinet. The box is an IKEA storage box which cost about US$5. The box is stuffed heavily with cotton foam. The resulting response is estimated using a worksheet which eventually will develop a Linkwitz transformation to enhance the bass (presented later). Without equalization the bass response will be very limited.
Tomi Engdahl says:
(Negative) feedback reduces distortion. Lack of feedback causes more distortion.
Tomi Engdahl says:
What does Class D speakers mean?
A class-D amplifier or switching amplifier is an electronic amplifier in which the amplifying devices (transistors, usually MOSFETs) operate as electronic switches, and not as linear gain devices as in other amplifiers.
Wikipedia
Class-D amplifier – Wikipedia
Part of a video titled What are the differences between Class A, AB, and Class D amplifiers?
5:52
9:14
But that in general is the difference now let’s go on to Class D Class D is a whole different way ofMore
https://m.youtube.com › watch
What are the differences between Class A, AB, and Class D amplifiers?
LISÄÄ TULOKSIA
Do Class D amplifiers sound bad?
Early class D designs didn’t do this very well: high degrees of particularly harsh intermodulation and odd order distortion were common, switching artifacts often remained in the audible band, and phase/magnitude linearity often began to suffer greatly in the upper octaves.
Tomi Engdahl says:
Many Class D amplifiers utilize negative feedback from the PWM output back to the input of the device. A closed-loop approach not only improves the linearity of the device, but also allows the device to have power-supply rejection.
https://www.analog.com/en/technical-articles/fundamentals-of-class-d-amplifiers.html
Tomi Engdahl says:
Silver would be better. Silver is better conductor than gold
Silver will oxidise black but still conductive.
“black” silver is not oxide but sulfide
Tomi Engdahl says:
Copper is more conductive than brass, but it is too soft to be utilized in electrical equipment such as sockets and plugs.
CMC makes gold plated pure copper. I hate to admit I’m not sure I hear a difference, though.
Just don’t use dissimilar metals, as that can cause “Contact Point Rectification.”
Gold is better than copper
The resistivity* of gold is 2.214E-8 ohm meters at room temperature. The resistivity of copper is 1.72E-8 ohm meters. So a gold wire has about 29% higher resistance than the same size copper wire. Many people picked up the erroneous idea that gold is a better conductor than copper because it’s often used on contacts.
It is true that Gold does not oxidize easily and looks “cool” and is expensive.
Tomi Engdahl says:
Soldering copper wires make good contact when you solder wire to connector, but be careful that copper cable can become brittle where soldering ends so make sure it will not be bent too much there.
Soldered wire in screw tightened connection is not a good idea in high current carrying application as contact will become loose over time when it gets hot and cold.
Tomi Engdahl says:
The biggest blindspot I see with audiophiles is the fact, scientifically proven, that you cannot trust your ears to judge the quality differences between products unless you have a very restrictive blind A/B test environment.
Ignoring this fact is exactly why so many snake oil products thrive.
Tomi Engdahl says:
The point was simply that A/B testing is the only environment where your ears can retrieve even a partially reliable comparison result.
For example, there are huge differences between listener judgment of which thing sounds better when they are permitted to know what they are listening to … that statistically vanish when the exact same thing is tested blind.
Similarly, if great care is not taken to exactly balance the volume of the two compared items, the louder will always be preferred.
These are simply facts.
If you carelessly trust your (eyes and) ears, you will be fooled.
Tomi Engdahl says:
https://www.facebook.com/groups/DIYAudio/permalink/6739826349416487/
Yet another thread trashed by snake oil AND naysayers. I would really love to talk about how our ears and brains work instead of this pseudo science demanding cable lifters OR AB testing.
In my view, AB testing is NOT at all suitable for audiophiles, not because they do not understand the results, rather because AB only works when we are comparing VERY similar things without a characteristic that lets us immediately recognize which A or B is playing. In addition AB testing requires very exacting test parameters almost impossible to achieve at home. I get the feeling that when I read “AB Test”, run the other way because it is also a form of snake oil in the hands of those NOT in the know.
As far as audio recordings uploaded to Facebook, it makes no difference if it is made by a telephone or a Schoeps microphone. It is currently impossible to upload a room experience.
Just to make it clear where I am coming from, I am a (performing) professional classical trumpeter very familiar with the real sound of an orchestra in a very fine hall.
Robin Wukits It was the scientists that wanted to figure out how our ears and brain worked who did the experiments to prove conclusively that you can’t trust your hearing except under tightly controlled A/B circumstances.
So I don’t see any cogent way around that fact.
It should be embraced, the measurement role enhanced…because there real differences and snakey claims can both be revealed.
Peter Campbell except for the fact that AB only works under laboratory conditions – something NOT generally even possible for the audiophile.
I did not say trust our ears blindly (although all of the naysayers keep trying to put those words in my mouth). AB is great for those with the environment and discipline to spend tons of time with. It is absolutely useless with a home hifi where we have no real control of humidity, temperature, or even getting the differences so miniscule that AB even makes sense. It is worthless for audiophiles comparing speakers, phono cartridges or even tube rolling in the same amplifier.
In a perfect world where every audiophile is a well trained engineer and every listening room is a well controlled laboratory, AB still would be the WORST way to get a system plausibly playing music. Perhaps we could use it to compare output transistors – seldom the real goal in any home system. AB does not even work to get a balanced “to the ear” frequency response (from the left and right speaker). It is also useless to choose between an Ortofon and Koetsu phono cartridge (house sound coloring test).
As I originally posted, AB is a snake oil term for many without any idea what it means. That does not mean that EVERY mention of AB is bad but certainly every post without mention of the entire process and parameters is. I am tired of the pseudo scientists using terms out of context. No one shows their knowledge by posting “AB”. They do by posting PROCESS and the parameters to get there.
I will make it easy for you: describe in detail how to pick using AB (or ABX) between 2 tweeters (let us say a ¾” ScanSpeak and Focal) in otherwise the same speaker. As they both have a house sound, you can not use AB to pick them – it is too easy to tell which one is which – destroying the meaningful evaluation as personal preference will always win on short term testing. You can use any type of amplification, caps, coils, wire or even DSP.
The method with the best chance of success, is to LIVE with one tweeter for a couple of months. Take notes, then switch to the other for a couple of months. Each experiment requires an acclimation period after which we can make meaningful comments. At the end of the evaluation period, you can make a decision – not based on AB, rather how the tweeter interacted in lifestyle during the evaluation period.
I did not expect that the average audiophile would have pragmatic access to a scientifically adequate AB environment, rather I simply stated that if you think you can judge accurately* without one then you are wrong. Because the science says so.
* Here is where the divergence often gets confused. I am talking about accuracy. If two devices meet a known standard of accuracy (say two DACs) then it is known that even experts in an A/B test cannot distinguish between them.
Or in your tweeter example, if the two were equalized and used in an amplitude and frequency range where they exhibit similar distortion and dispersion characteristics, you would not be able to tell the difference.
You seem to be talking about preference, not accuracy.
People can prefer anything, and no AB test helps that.
I seek one goal…accuracy.
Peter Campbell agree with this 100%. All the fancy interconnect speaker cables and huge heart shrink art power cables never seen any blind testing or measurements.
Tomi Engdahl says:
https://www.facebook.com/groups/DIYAudio/permalink/6739826349416487/
It was the scientists that wanted to figure out how our ears and brain worked who did the experiments to prove conclusively that you can’t trust your hearing except under tightly controlled A/B circumstances.
So I don’t see any cogent way around that fact.
It should be embraced, the measurement role enhanced…because there real differences and snakey claims can both be revealed.
Peter Campbell except for the fact that AB only works under laboratory conditions – something NOT generally even possible for the audiophile.
I did not say trust our ears blindly (although all of the naysayers keep trying to put those words in my mouth). AB is great for those with the environment and discipline to spend tons of time with. It is absolutely useless with a home hifi where we have no real control of humidity, temperature, or even getting the differences so miniscule that AB even makes sense. It is worthless for audiophiles comparing speakers, phono cartridges or even tube rolling in the same amplifier.
In a perfect world where every audiophile is a well trained engineer and every listening room is a well controlled laboratory, AB still would be the WORST way to get a system plausibly playing music. Perhaps we could use it to compare output transistors – seldom the real goal in any home system. AB does not even work to get a balanced “to the ear” frequency response (from the left and right speaker). It is also useless to choose between an Ortofon and Koetsu phono cartridge (house sound coloring test).
As I originally posted, AB is a snake oil term for many without any idea what it means. That does not mean that EVERY mention of AB is bad but certainly every post without mention of the entire process and parameters is. I am tired of the pseudo scientists using terms out of context. No one shows their knowledge by posting “AB”. They do by posting PROCESS and the parameters to get there.
I will make it easy for you: describe in detail how to pick using AB (or ABX) between 2 tweeters (let us say a ¾” ScanSpeak and Focal) in otherwise the same speaker. As they both have a house sound, you can not use AB to pick them – it is too easy to tell which one is which – destroying the meaningful evaluation as personal preference will always win on short term testing. You can use any type of amplification, caps, coils, wire or even DSP.
The method with the best chance of success, is to LIVE with one tweeter for a couple of months. Take notes, then switch to the other for a couple of months. Each experiment requires an acclimation period after which we can make meaningful comments. At the end of the evaluation period, you can make a decision – not based on AB, rather how the tweeter interacted in lifestyle during the evaluation period.
I did not expect that the average audiophile would have pragmatic access to a scientifically adequate AB environment, rather I simply stated that if you think you can judge accurately* without one then you are wrong. Because the science says so.
* Here is where the divergence often gets confused. I am talking about accuracy. If two devices meet a known standard of accuracy (say two DACs) then it is known that even experts in an A/B test cannot distinguish between them.
Or in your tweeter example, if the two were equalized and used in an amplitude and frequency range where they exhibit similar distortion and dispersion characteristics, you would not be able to tell the difference.
You seem to be talking about preference, not accuracy.
People can prefer anything, and no AB test helps that.
I seek one goal…accuracy.
Tomi Engdahl says:
Process of Making High End Stereo Speaker. Wonderful Sound Engineer of Korea
https://www.youtube.com/watch?v=fXr6qCNxuq8
Tomi Engdahl says:
https://www.facebook.com/groups/ElectronicParts/permalink/2239471196242203/
It’s actually the input value that’s misleading here, due to how the regulations for its calculation are framed.
A respected amp designer replied to one of my comments on this subject with “The AC input power is required for any amp to be the current draw at 1/8-rated RMS audio power at the lowest rated nominal impedance for any amplifiers compliant with IEC 60065 or 62368 safety standards. The standards also include a provision that if an amplifier is intended to and marketed to drive more than 1/8-duty cycle, the stated AC input draw MAY be increased to account for the increased (more severe) duty cycle. ”
So… 110W input power being more than 1/8 of the 700W RMS continuous power is reasonable.
The designer in question uses 1/4 to 1/3 to be more realistic, and some manufacturers use higher figures.
110W power consumption is measured under 1/8 of output power. EN60065 is like that.
Tomi Engdahl says:
The best learning experience is to test it yourself. Nothing you read, no opinions substitute for personal experience. When you test, be sure to change only one component at a time to avoid mixing results. Listen to the same passages over the same equipment. Do not waste your time clicking back and forth between two specimens. Come back the next day and do it again. Try it at different times of the day as the human body/ear change sensitivity over its daily cycle and with changes in air density. Try many different recordings. Give the experiment time to evolve. You will discover what you seek.
Tomi Engdahl says:
https://www.facebook.com/groups/DIYAudio/permalink/6748099428589179/
Why do some turntables have ground wires (usually older) and others do not (usually newer)? How do they handle grounding differently that either requires the wire or not? Should I be adding a wire regardless?
Some modern consumer turntables come stock with built in pres. You should have said that and nothing much else
The TT needs to have the same ground potential as the phono pre amp.
If the pre amp is built into the TT then it is the same potential.
If the pre amp is separate from the TT you need a ground wire to make the TT and pre amp the same ground potential. Some TT use one of the rca shields as the ground. This is not a good solution.
For this reason, good quality TT’s have a separate ground wire.
If you’re TT uses one of the shields and you add another ground wire you will create a ground loop that can cause problems.
Tomi Engdahl says:
https://www.facebook.com/groups/DIYAudio/permalink/6749318378467284/
Can anyone give advice on improving a solid state power amplifier power supply..???.. I’ve heard so many different things. Like changing the bridge rectifier to ultra fast diodes, or soft recovery, or shottky diodes…. And putting snubber caps across each diode, and then I saw a circuit somewhere where each diode had a 10k resistor across it. I’m confused.
I know that increasing the reservoir caps gives better bass, but I’m confused about anything else. Can someone advise or direct me to a diy website?
The job of the power supply is to produce as clean a DC as possible, with the lowest possible output impedance. Increasing reservoir capacitance may help, but will subject the rectifier diodes to higher peak current and will still be limited by the current the transformer is able to supply. Beyond a certain capacitance, further increase will only lead to problems. Capacitors with lower ESR will always be a good thing, as this affects how fast the caps are able to dump current. “Ultra fast” diodes will make no difference, as “fast” in diode context applies to handling of frequencies well above the audio range.
In short, “increasing the reservoir caps gives better bass” is not necessarily true. I would measure how the power supply behaves under max load in order to understand where there is potential for improvement. If the limitation is given by the transformer, bigger caps won’t make much of a difference.
if you have no hum on no signal,and you do not have DC rail sag at reasonably high vol levels,then there is no problem,if it is higher headroom you seek,then quadruple the output of your amps by upgrading the modules.You need to quadruple the output power in order to hear it to be louder as our ears can only hear a 3DB change.
Tomi Engdahl says:
https://www.facebook.com/groups/DIYAudio/permalink/6749318378467284/
Can anyone give advice on improving a solid state power amplifier power supply..???.. I’ve heard so many different things. Like changing the bridge rectifier to ultra fast diodes, or soft recovery, or shottky diodes…. And putting snubber caps across each diode, and then I saw a circuit somewhere where each diode had a 10k resistor across it. I’m confused.
I know that increasing the reservoir caps gives better bass, but I’m confused about anything else. Can someone advise or direct me to a diy website?
“changing the bridge rectifier to ultra fast diodes,”
Ultra fast diodes make sense in switch mode power supplies and other high frequency circuits. They offer no benefit I know of compared to traditional rectifier diodes when used after normal mains transformer.
” or soft recovery,”
Soft recovery diodes are optimized to reduce losses and EMI/RFI in high frequency power conditioning systems. The softness of the recovery eliminates the need for a snubber in most applications.
They offer no benefit I know of compared to traditional rectifier diodes when used after normal mains transformer.
“or shottky diodes….”
Schottky diodes are really fast, have fast soft recovery and typically have low voltage drop. Good features, but with traditional mains frequency power supply circuits you are pretty much left with only somewhat lower voltage drop as benefit.
The most evident limitations of Schottky diodes are their relatively low reverse voltage ratings, and their relatively high reverse leakage current. They are prone to self-destruction via thermal runaway if the power dissipation, heat-sinking, and operating temperature conditions are not properly taken into account.
“And putting snubber caps across each diode,”
Capacitors are sometimes placed across solid state rectifiers in the power supplies of radio transmitters and receivers to prevent the rectifiers from modulating rf leaking into the power lines and ground as that can produce hum.
“and then I saw a circuit somewhere where each diode had a 10k resistor across it.”
I can’t think of a good reason for that.
“I’m confused.”
Hifi DIY field is full of confusing information.
Some are true, some are true in some cases, some folklore widely believed to be true while it might not and there are also many lies told by snake old salesmen.
“I know that increasing the reservoir caps gives better bass”
In some cases yes if the original capacitors had too low capacitance for the application. In many cases with originally well built amplifier I expect no considerable difference.
Tomi Engdahl says:
1.Use shottky diodes because they do not have reverse recovery.
2 RC snubbers across all secondaries. Adjust values until ringing is gone.
3 Input AC filtering
4 DC blocking at AC input (depends on your mains quality)
Tomi Engdahl says:
Bernard Ulrich
“1.) no residual electronic hum at low level in your loudspeakers (can also be generated by bad inputs ground connection)”
Hum can be generated by many things in audio circuits. Of the noise main frequency is 100 or 120 Hz, it could be caused by power supply issues where voltage does not stay stable between full wave rectifier output peaks (too low capacitance for filtering) or other power supply issue (wrong grounding of DC output side)
If the main component in noise is 50 Hz or 60 Hz, the noise comes most probably mains frequency getting to the circuit through magnetic coupling, capacitive coupling or grounding issues (groundloop, lack of grounding)
2.) no audible distortion at high level (this is mainly capacitor related.
Distortion at high output level can be caused by capacitor issues, but can be also caused by a dozen other issues as well.
Tomi Engdahl says:
“1.Use shottky diodes because they do not have reverse recovery.”
Is there any practical effect of that reverse recovery on power supplies with 50 or 60 Hz transformers?
I know that at high frequency circuits the effect is real and can be very considerable.
“2 RC snubbers across all secondaries. Adjust values until ringing is gone.”
Snubbers can be useful yes.
“3 Input AC filtering”
Yes this important to keep RF noise out of your audio circuits. I have used them successfully.
“4 DC blocking at AC input (depends on your mains quality)”
I have never had need for DC blocking with any traditional EI core transformers that are not very DC sensitive. Toroidal transformers are typically much more sensitive to mains DC.
I have not needed to add DC blocker to any of my own build or device I own.
Tomi Engdahl says:
if you have no hum on no signal,and you do not have DC rail sag at reasonably high vol levels,then there is no problem on power supply or it’s capacitors
Tomi Engdahl says:
Ultrafast diodes May increase noise in some circumstances. I am not keen on Schottky diodes in this application, I could almost make a living out of replacing 1N5822’s. The first question to ask yourself is ‘do I have a problem?’ Identify the problem and measure it , then see if the change has made a difference.
Tomi Engdahl says:
Capacitors that regain charge over time after a short discharge are exhibiting dielectric absorption. Dielectric absorption is charge retained in the dielectric due to finite time required for electric dipoles to completely lose the alignment resulting from charging.
Dielectric absorption is predominantly observed in film caps (small) and electrolytic caps (larger).
Dielectric absorption can cause certain circuits, particularly certain reset circuits, to misbehave.
In rare cases, when the initial stored charge, voltage, or both is large, dielectric absorption can cause dangerous conditions to “mysteriously” re-appear at a capacitors terminals after a period of time. In these cases it is recommended to keep a shorting strap on capacitors after an initial controlled discharge.
Glass dielectric capacitors, like the second anode terminal on a CRT, can be subject to dielectric absorption. This occasionally causes unpleasant surprises during CRT service.
https://en.m.wikipedia.org/wiki/Dielectric_absorption
Tomi Engdahl says:
From
https://m.facebook.com/groups/DIYAudio/permalink/6749318378467284/
The job of the power supply is to produce as clean a DC as possible, with the lowest possible output impedance. Increasing reservoir capacitance may help, but will subject the rectifier diodes to higher peak current and will still be limited by the current the transformer is able to supply. Beyond a certain capacitance, further increase will only lead to problems. Capacitors with lower ESR will always be a good thing, as this affects how fast the caps are able to dump current. “Ultra fast” diodes will make no difference, as “fast” in diode context applies to handling of frequencies well above the audio range.
In short, “increasing the reservoir caps gives better bass” is not necessarily true. I would measure how the power supply behaves under max load in order to understand where there is potential for improvement. If the limitation is given by the transformer, bigger caps won’t make much of a difference.
Peak inverse voltage is given by what comes out of the transformer secondary. A capacitor cannot increase a voltage; what it does is resist change in voltage (“Someone is trying to increase my voltage; let’s sink current to resist it. Someone is trying to decrease voltage; let’s source current to resist it.”)
Peak current is another history; larger caps need more current to charge, so peak current will increae.
Richard Becke “Capacitors with lower ESR will always be a good thing, as this affects how fast the caps are able to dump current.”
Not always. I’ve heard of some vintage designs (ie 1960s/70s) that were designed with higher ESR caps in mind and changing them out with modern ESR caps actually caused issues because of it.
Tomi Engdahl says:
the new Class D amplifiers sound every bit as good, if not better. Class D has always been controversial to the so called real so called Hi Fi buffs. Guess that is what makes the world go around. Your opinion will not change mine and I am rather sure nor will my opinion change yours. Enjoy the music, however you do it.
Class AB1 or AB2 is the standard; reasonable efficiency, and there are many designs to choose from. Class A if you want “purity” but at a high energy and heat cost. Class D is super efficient, but “real” audiophiles may turn up their noses at it, since it’s such a counter-intuitive way to make a low distortion audio amplifier.
Tomi Engdahl says:
If you’re looking to the future, then go for a Class D amplifier or other switching type amplifier. From an educational standpoint, Class D will give you exposure to analog and digital electronics, filter design, signal modulation, and power design. The things you learn can be applied to other areas including Switching Power supplies and industrial electronics. Also, look into using some of the new power devices like GAN transistors. I would recommend using an integrated circuit for the digital modulator with external power devices; you’ll learn more than with a single chip device. Good luck and welcome to a wonderful profession!
Tomi Engdahl says:
Generations X, Y and Z have embraced tube amps along with vinyl LPs and film cameras.
Tomi Engdahl says:
Does anyone still use mp3? In any case, mp3 at a decent bit rate is more transparent than vinyl, but class D is good for pretty much anything.
Tomi Engdahl says:
Mobiles and internet mostly use AAC, a much better codec. Anyway, with lossy codecs the quality depends on the bit rate – so you can’t just say “mp3 is good” or “mp3 is bad” without also referring to the bit rate.
Vinyl is equivalent to 12 bits @ 44 kHz on a really good day, but also has much more distortion and coloration (as well as wow and flutter).
Tomi Engdahl says:
“huge difference between analog tube amps and digital, esp when they clip.”
if the modern amplifier or tube amplifier clips when you use it to play back audio recording, you are doing it wrong.
With tube guitar amplifiers pushing it to clipping to get certain distorted sound is often intentional. Modern take to get the same sound is to use DSP based effect pedals to get the right distorted sound that is fed to modern class D amplifier.
Tomi Engdahl says:
The valve “sound” is distortion. Nothing less.
You can’t improve the quality further down the chain. Most important is the source followed by amp and speakers last.