What is responsible for soundstage in a preamp design?

[abbey road d enfer]

WRT to H3/odd I wasn't thinking just about power amps but op amp output stage loading, class-A push-pull running out of steam during current peaks, transformer saturation, symmetrical diode limiters, supply sag etc, that bend the I-V curve identically in both quadrants I and III. These examples are all compressive odd-order.

Agreed. Note I precised "unless driven into clipping".

For the record I've never used the word "soundstage" except to describe a building where film and video are recorded and I've never heard a difference in cable direction.

+1 on both.

 

[KA-Electonics.com]

9) (Added.) If one of the preamps being compared has an input transformer, is its core magnetized by a prior phantom fault? That will add H2. I've had clients who de-Gauss'd their input transformers with high level LF tone every once-in-awhile.

Added #9 to my OP in this thread.

 

[KA-Electonics.com]

What you hear here is the Barkhausen quantisazion or -distortion. It's simply a threshold function determining the minimum-energy-level transferable because of ferromagnetic "cell" or crystal size, and the related energy content required to flip these. The better magnetic conductivity, the smaller crystals and the longer the "tails" of natural-room reverb..

If you want to hear something extreme in this direction, try a nano-crystalline or amorf-core mic stepup transformer - to me that was an almost scary experience

/Jakob E.

Why tape is biased.

 

[JohnRoberts]

Added #9 to my OP in this thread.

I stopped using audio transformers in my designs after low noise transistors offered a viable alternative for low noise mic preamps ( late 70s-early 80s).

=== Later at Peavey I/we used tons of audio transformers for the AA fixed install market (they insisted on transformers and the customer is always right, even when wrong.)

Transformers were a premium option for some sound reinforcement SKUs, not for some etherial sound quality but for robustness in fast and dirty sound interfaces for live sound (the show must go on, right now).

JR

 

[user 37518]

The oposite as the direction of a cable can be heard at a first comparison but later it settles so the direction doesn’t matter after all (not sure how to phrase that differently as it does sound silly). Maybe to be compared to transformers that need time in case a dc voltage had been applied, this is beyond me but has been proven many times especially on unballanced systems.
As many things “the proof is in pudfing” and can’t be expressed in numbers as for me the equipment to measure it is not available. Also even small difference can be heard it is not always implemented as the implementation takes too much effort for such a small difference.
That is why high end stuff costs so much more not only for build quality and marketing.

I have worked in the audio business for many years before changing to the pro world. In the pro world this is something not to discuss but in the high end audio this is possible. Now i know of many so called audiophools ( mentioned already here) as these mainly are people without a technical background. As i am very sceptical ( maybe this looks strange to you) i need to be convinced personally, so i do invite sometimes people who claims to have something interesting to show or they send me a product to test. This because it is known to people arrond me that my setup is all revealing (even though it is never finished) and minute changes can be heard. So this for me is prove (1st hand / ears ) not any numbers or stories/reviews presented.

One of the products i was asked to test was this cable (some years ago already) at first nothing interesting but a few days later it was very audible that it does work as advertised ( i use the power cables not speaker cables as i don’t use low impedance loudspeakers).

Do you have anything other than anecdotal evidence to back up your claims? some measured figures? some references?

 

[gyraf]

Why tape is biased.

Yes. Am I allowed to back-bias in reverse out through my input transformer, perhaps adding a bias trap to the input side of transformer to not mess with the mic?

/Jakob E.

 

[Lampie519]

Do you have anything other than anecdotal evidence to back up your claims? some measured figures? some references?

There are many so called “award winning” companies that provide directional cables and are used at many audio shows. Maybe a good idea to attend one of those for a change and talk to the designers of these cables. In the Netherlands we have a very successfull designer of audiophile cables: A.J. van den Hul
Please check him out.

 

[JohnRoberts]

It is not very productive to argue with people about what they say that they hear on the Internets.

The only way to prove such claims is with rigourous controlled double blind listenting tests that realize statistical significance.

Enjoy...

JR

PS: I also wrote a column about wires/cables for my RE/P "Audio Mythology" column back in the 80s.

 

[k brown]

My all-time favorite cable story was from the top Classical engineer, Tony Faulkner.

He was invited to bring some of his recordings to play as part of a demo at a HiFi trade show. Someone asked about the speaker cable he had hooked up the Quads with:

"Yes, they would look familiar if you have a garden. Before the show opened we went over the road to the DIY superstore and bought one of those £20 extension leads that Black & Decker sells for electric hedge-cutters. They are made from good, thick copper wire, look nice and sound good to me. The show's been running for three days and no one in the audience has noticed..."

 

[Cranehazard]

Normally, you can't connect the mic directly to an op-amp if you intend to achieve the lowest noise figure, so a transformer or a discrete stage is needed, that is the main purpose of these components, not so much to add what people call coloration. However, I see absolutely nothing wrong with the sound of the IA IC's which are meant to be used as a preamp, like the INA217.

The INA217 is an instrumentation amplifier like the ones used in the interface mic preamps. This is why I believe the effect that the original poster is not present when using them.

 

[Ricardus]

There are many so called “award winning” companies that provide directional cables and are used at many audio shows. Maybe a good idea to attend one of those for a change and talk to the designers of these cables. In the Netherlands we have a very successfull designer of audiophile cables: A.J. van den Hul
Please check him out.

So, for the record... you're being serious here?

 

[Tubetec]

If I was assembling a bunch of audio cables I'd probably just send the signal in the same direction as the print on the cable jacket ,just because .
In certain configurations where a sheild is left unconnected at one end ,signal direction does matter ,but theres a rational explanation .
This atomic physics mixed with voodoo is only marketing department bullshit ,
The resistance and capacitance of a twisted pair doesnt vary depending on which end you measure from does it?

 

[user 37518]

There are many so called “award winning” companies that provide directional cables and are used at many audio shows. Maybe a good idea to attend one of those for a change and talk to the designers of these cables. In the Netherlands we have a very successfull designer of audiophile cables: A.J. van den Hul
Please check him out.

Really, that is your evidence? The guy in the YouTube vide with a snake? You are basically telling me that because companies like Monster Cable say so it must be true. To be honest, I expected more, considering that you have been claiming a lot of things.

 

[user 37518]

So, for the record... you're being serious here?

I think that comment pretty much sums up all my thoughts.

 

[user 37518]

The INA217 is an instrumentation amplifier like the ones used in the interface mic preamps. This is why I believe the effect that the original poster is not present when using them.

I see nothing wrong with the INA217 or the fact that it is used in interface mic preamps. We don't even know what the original poster means, so we can't assume that it is due to parts like the INA217.

 

[abbey road d enfer]

The INA217 is an instrumentation amplifier like the ones used in the interface mic preamps. This is why I believe the effect that the original poster is not present when using them.

Actually, the structure of the INA217 is a textbook 3-opamp instrumentation amp, when the dedicated mic preamp chips are essentially a Cohen arrangement. Potential differences are slightly better distortion for INA217 and slightly better noise for SSM2019. Instrumentation amp has 4 input devices, when Cohen has only 2.
I don' t think the differences can be heard in normal use.

 

[abbey road d enfer]

Really, that is your evidence? The guy in the YouTube vide with a snake?

Yes, I wouldn't believe one second that this guy has no financial interest in preaching this BS. Under the mask of coolness, he is so transparent...

You are basically telling me that because companies like Monster Cable say so it must be true.

At least, Monster Cables are honest. Most of their patents are for packaging.
In most european countries, it is not a real patent, it's a registered design, somewhat akin to a trade mark.

 

[Mr. Moscode]

"Soundstage" is a metaphor that promotes the idea of audible location of sounds in the presentation. That's all. No stage, just sound. Singer on the left, right, in the middle, front or back? etc. It's not meant to be literal.
What's the harm in it??

Don't all you great engineers strive for a mix that makes you want to listen? Pull you in, provide listening pleasure?

Didn't Hugh Hefner airbrush Miss October?

Throwing this into the mix. Does O2 free copper sound better or are you content with some zip cord from an old lamp?

 

[abbey road d enfer]

"Soundstage" is a metaphor that promotes the idea of audible location of sounds in the presentation. That's all. No stage, just sound. Singer on the left, right, in the middle, front or back? etc.

And a single mic preamp can do that? (that's the original question)

It's not meant to be literal.
What's the harm in it??

No harm, but confusion, which is not welcome in a scientific discussion.

Don't all you great engineers strive for a mix that makes you want to listen? Pull you in, provide listening pleasure?

Yes we do, but what does it imply in this discussion? Do you surmise that de-bunking myths is detracting from the search for good entertainment?

Didn't Hugh Hefner airbrush Miss October?

If you mean adding a little make-up, it's what SE's do by choosing the right signal chain, adding EQ, FX and whatnot. There's no need for improper description. There's no lack of proper words for this.

Throwing this into the mix. Does O2 free copper sound better or are you content with some zip cord from an old lamp?

As long as the electrical properties are identical and the contacts are good, I don't see why not. But I wouldn't use a zip cord for loudspeakers (cause too small gauge) or for mics (cause not shielded).
There has never been any proof that OFE (Oxygen-Free-Copper) has significantly better electrical performance than standard ETP (electrolytic-tough-pitch). The 1% difference in conductivity is irrelevant in view of the large possible variations in length of cables.
Being oxygen-free does not necessarily make a cable suitable for a job.

 

[user 37518]

As long as the electrical properties are identical and the contacts are good, I don't see why not. But I wouldn't use a zip cord for loudspeakers (cause too small gauge) or for mics (cause not shielded).
There has never been any proof that OFE (Oxygen-Free-Copper) has significantly better electrical performance than standard ETP (electrolytic-tough-pitch). The 1% difference in conductivity is irrelevant in view of the large possible variations in length of cables.
Being oxygen-free does not necessarily make a cable suitable for a job.

I just laugh whenever I hear the argument that some copper cables act like little diodes. I honestly look for sturdiness and shielding in a cable, rather than whether it is oxygen-free copper or not; oxygen-free copper is pure snake oil.

One only aspect that I think that can make a significant difference (besides noise immunity) in a cable is cable capacitance, which can impair high frequencies in long runs, especially if the impedance of the source is high, in which case, changing the geometry of the cable or making it braided, etc.. could have an impact. However, in most cases, it is all BS, and, besides, whether the copper is oxygen-free or not should make no difference in this aspect. In pro-audio the source impedances are usually very low.