Vintage mojo... What is it exactly?

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abbey road d enfer

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If a modern high-end signal transformer has less leading phase shift in the bottom end than a vintage counterpart, you might hear that (and prefer it or not).
That should be measurable in the frequency response test. Transformers are Minimum Phase devices, hence the phase and frequency responses are directly correlated. It's been demonstrated times and times that, in this case, it's the frequency response perception that dominates.
 

JohnRoberts

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somethings you just can't quantify.
I had a company I worked with decades ago try and copy a transformer design in the hopes they could make a less expensive version of the name brand they were using. The idea was new part number, less costly, and some marketing spin and done. So after voicing my concerns, we had test samples made. When they arrived got to testing right away. After all the testing and measuring, the clones measured pretty well compared to originals while at the same time sounded something awful by themselves and sounded no where close to the originals.
if something measures good but sounds bad, you are not measuring the right thing, or right way.

JR
Other times it can be something as simple as it looks the part so people and their brain say it is. For example, my current studio wants to make more modules for our desk, but they insist they get made like the originals with large ass wiring looms because that is what makes the difference.

Then other times, it's just belief. For example my buddy at an audiophile show once told the guy giving the demo that the cable lifters they used were the wrong ones for that type of demo music. He had them convinced they needed to use another kind. It was funny.

and sometimes it's in the details. Age can effect how things sound. Like an acoustic guitar that matures and sounds good when you get it and great after many years of being played.
 

pucho812

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if something measures good but sounds bad, you are not measuring the right thing, or right way.

JR
I've heard that if it measures right and sounds like shit, you measured the wrong thing.
While I agree with you, I can assure you, we measured everything as much as you can with a transformer. But anyway that was years ago.
 

JohnRoberts

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I've heard that if it measures right and sounds like shit, you measured the wrong thing.
While I agree with you, I can assure you, we measured everything as much as you can with a transformer. But anyway that was years ago.
Back in the 70/80s I had to roll some of my own test equipment because typical inexpensive bench equipment (like heathkit) didn't capture everything.

The main issue I had sourcing Chinese transformers last century was that the vendor didn't know what mu metal was... but they eventually figured it out.

For vetting audiophile transformers consider null testing to objectively see how they differ. However that won't tell you which one is causing the difference. If they deliver a deep null, they should sound similar. I can imagine differences from core material, winding wrap/coupling. etc.

Caveat, I am not a transformer guy either.

JR
 

Bo Deadly

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For vetting audiophile transformers consider null testing to objectively see how they differ. However that won't tell you which one is causing the difference.
That's what a "control" is for. Null test two units that you know to be identical. Then null test with one DUT. The difference between the control and the DUT tests is attributed entirely to the DUT because that is what changed.
 

Fdieck56

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The ear/brain combination is an amazing processor which learns and is trained from the day you are born. Naturally produced sounds have a harmonic structure (timbre) where the higher harmonics steadily fall off in level. The shape of this harmonic structure depends not only on the sound creator but also on how loud it is played. So when we hear a recorded instruments we can tell if it is played soft or loud and also if it harmonic structure is right.

Often the harmonic structure is altered by the recording and replay process and again we can tell when this occurs. The most obvious one is where the bandwidth is limited e.g. AM radio, and we say it sounds "dull". Sometimes the harmonic structure is altered so that certain harmonics are changed more than others. If the third harmonic is emphasised it tends to sound louder. If the second harmonic is emphasised it tends to sound clearer or crisper.

Tubes and semiconductors produce different harmonics in different proportions. In tube mics, the amplifier is almost always a class A single ended type. with no negative feedback. At modest levels this topology tends to produce almost entirely second harmonic distortion which makes things sound clearer. As the level increases, third harmonic distortion begins to occur which makes things sound louder.

Perhaps this goes some way to explaining what you hear.

Cheers

Ian
The two best amplifier designers I know of Jean Hiraga and Nelson Pass say 2nd and 3 harmonic distortion with a distinct lack of higher harmonics are what the design for. Nelson says the phase of the second harmonic with respect to the fundamental makes a difference and Jean sought a certain amplitude ratio of 2nd over 3rd harmonic is desirable. I have also read that 5th harmonics are very objectionabl. Those single end triode guys love lots of 2nd harmonic even into the several % numbers.
 

Fdieck56

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Can’t you do both? You might think doing something for over 40 years and getting wealthy doing it you might know what your doing…. Nelson has put much of his design out there for the DIY community for about 30 plus years.
 

abbey road d enfer

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Can’t you do both? You might think doing something for over 40 years and getting wealthy doing it you might know what your doing…. Nelson has put much of his design out there for the DIY community for about 30 plus years.
Jean Hiraga has put a whole generation of audio enthousiasts on a wild goose chase with his DIM notion, which is the electronic version of the paradox of Zenon of Elea, in which the arrow can never hit the turtle.
And Pass rehashes his single-ended harmonics generators.
 

Walter66

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Jean Hirage promoted first here in europe the triode tube audio revival to the audio scene (specially the folks of Le Audiophile in france).
When doing this by presenting old style WE and other famous gears of the golden analog tube audio era in a small cinema in Paris, he used to learn his stuff from the japanese, which introduced him to their audio systems. Because the asians were clever and had an ear for the qualities of the US- audio gear from the 1920's on upwards, they purchased every WE system they could get a hold on and installed those big cinema systems at their small and tiny homes.
After learned and being educated about that sound, Hiraga went to europe again and made big marketing about those systems and their ideal of triode low wattage amps combined with big horn systems from the 1930s when audio in the US went towards become a commercial success.
Hiragas own circuits were heavily influenced by those audio designs, while what he designed himself being relative irrelevant, just for some freaks of the audio scene it became important.
So Hiraga's most importance lies in the fact that he introduced the european audiophiles with their own audio history, bringing the big names of european tube audio (and the US, of course) back into the game of what audiophile dreams are being created.
He himself must have made a fortune from his knowledge, achieved when such desirable things in europe went for the small money and some decades later brought the big cash to their owners. It was possible in the 1970s- 1980s to have a truck loaded with the garbage no other company any longer wants and usually had thrown into the bins for just a penny, making them run again and sell it for thousands of bucks to audiphiles.
And with those famous tubes it was the same. One can be sure that Le Audiophile and Hiraga had a stash of WE 300B tubes when they came up with their triode amp kits on the market, making a fortune selling it for a multiple they initially had to pay for the electron tubes.
Nelson Pass introduced himself to the audio community with his transistor gear, making it possible for the DIY to rebuild it by publishing its circuits in the scene. That was his way of guerilla marketing on those days to became a cult status in the audiophile scene.
The hidden quality treasures of those old gear and its noble sound lies in the art of manufacturing the parts and in the building style of the commercial pro stuff, which then in the later decades have been short cut by the penny pinchers of the controlling departments and have been made available for the ordinary audio consumer with the limited budget. Thats the way it was made for the big audio market which later have been taken over by the asians, making everything even more cheap in manufacture than the europeans and americans could ever do, due to their lower working salaries in the factories.
The fun story behind those known facts is, that the asians have sold their cheap style made audio systems to the foreign markets while being on treasury hunt for those old style tube audio systems around the world and buying everything in quantities, the older the better. Not telling the foreign audio scene and having themself an audio scene growing with old stuff which they hold hidden behind those language barriers that still exist today while the internet now has shown much of it even to the foreign world. They have grabbed everything good and sold their low quality audio mainstream stuff to the world instead.
 
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revmonkey

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There is a video somewhere on YouTube where Neve talks about Harmonic distortion and the BS that it is to track THD on anything. He references an old book from the 30s or 40s about building your own radios, where the author lists something like the first 15 order harmonics with maximum acceptable distortions. He also makes a point about even-order harmonic distortion being much easier on the ear than odd order ones. The jist is that a fraction of the amount of say 7th order harmonic distortion is way more audible and gross than a much larger amount of 6th or 8th order.

All of the assertions occurred way over my head. Bit I did find the book he was referencing at some point. I think the video was from some audio engineering summit in 2001 or so.
 

gyraf

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I think we all agree that certain distortions are horrible - what we don't all agree, is the possibility to quantify what types of distortion is "right".

IMO, if such quantification was even remotely possible, the effect would have been monetized digitally already 20years ago. And it's NOT for lack of trying :) from the software companies.

/Jakob E.
 

JohnRoberts

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This too is a mature topic in the effects discipline. There are many examples of successful effects that effectively add distortion to a clean path. These range from the crude guitar "fuzz" effect created with diode clippers, to more subtle vocal "exciters" selectively reintroducing overtone harmonics. I recall decades ago when I was still writing my "Audio Mythology" column for Record Engineer/producer magazine, I delved into the subject of adding distortion and may have jokingly equated oral exciters with fuzz boxes. I really didn't like the overuse of early exciters and would often try to tune in the FM station better to clean it up. This fuzz box characterization struck a sensitive nerve with the guy who was exploiting that effect commercially, triggering a nasty letter to the editor of RE/P. I guess he didn't know I would get last licks. :cool: FWIW I pulled a copy of his patent application and he admits to discovering the phenomenon by accidentally assembling a Heathkit preamp incorrectly. The euphonious early saturation distortion generated by his mistake became the inspiration for his patent and product.

[TMI] Human vocals are rich in harmonic overtones due to the relatively fixed length vocal cords expressing overtones at harmonic multiples of the fundamental. This is true for most stringed musical instruments, and wind instruments. Only drums are the odd ball instrument with non harmonic overtones. [/tmi]

JR
 

Gus

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The thicker the cores of the lower note strings like used in guitars, basses and pianos can be more non harmonic
 

soapfoot

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The thicker the cores of the lower note strings like used in guitars, basses and pianos can be more non harmonic
Yes, this is called "inharmonicity."

When a (particularly metal) string gets too stiff relative to its length, it begins to behave less like a theoretical string and more like a chime. This causes the overtones to deviate from the harmonic series, and is why piano tuners have to stretch the lower and upper extremes of the keyboard, to bring the harmonics of the lower strings more in tune with the fundamentals of the octave(s) above, and the fundamentals of the short upper strings more in-tune the the harmonics from the octaves below.
 
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