What is Transparency?

[tony ky ma]

Tranparency is the absence of distortion and electrical interference in a audio system.

Hi Roger
Transparency is one of the factor that you can hear the difference but no measuring ,the best way to taste the different degree of them is to make a quality master tape ( from live) and dub it as first copy, also dub it again from the first copy , compare these three tapes in a same system, you will know what the transparency of difference
tony ma

 

[c1ferrari]

The conveyance/transmission of a signal without change

 

[fas42]

What is the most transparent piece of electronica equipment that contributes the most (the best) in the overall 'audio invisibility'?

Actually, Bob, the way to approach this is not to say which is most transparent, rather to name that which is most obscuring: focus on what is causing the most problems, because that's where the greatest gains will be achieved if the deficiencies are addressed. Then you continue in a process of nibbling away at these weaknesses, until all is revealed -- you have maximum transparency!

Frank

 

[RogerD]

Hi Roger
Transparency is one of the factor that you can hear the difference but no measuring ,the best way to taste the different degree of them is to make a quality master tape ( from live) and dub it as first copy, also dub it again from the first copy , compare these three tapes in a same system, you will know what the transparency of difference
tony ma

Spoken from experience. Tony good for you and others who are lucky eneough to know the difference. Compare,compare,compare.

 

[NorthStar]

Actually, Bob, the way to approach this is not to say which is most transparent, rather to name that which is most obscuring: focus on what is causing the most problems, because that's where the greatest gains will be achieved if the deficiencies are addressed. Then you continue in a process of nibbling away at these weaknesses, until all is revealed -- you have maximum transparency!

Frank

Frank, that was exactly what my main intention was;
I simply took another route to get to that point. :b
Still as effective nonetheless.

* With time you'll make more discoveries ... And more you'll see the transparency ...

 

[Phelonious Ponk]

Which brings me to a question I asked but you never answered. If you had a choice between a system with electronics that were true to something simple like a sine wave but the sound wasn't or a hodge podge of gear with bumps here and dips there but in the end sound in the listening window was like the test signal. What would you choose? This isn't a matter of preference. Which one is high fidelity?

I don't understand the question. I've heard a lot of equipment, from the deliberately euphonic to designs that have gone to great pains to be as neutral as possible. I've never heard anything that sounded like a test signal.

Tim

 

[JackD201]

Let me rephrase. Measured output at the listening window represents the test signal better.

 

[Phelonious Ponk]

Are you asking if I would prefer a system with measurable imperfections that sounds right vs. a series of components that all measure well, but somehow don't sound right?

Tim

 

[JackD201]

Nope. Both are measured. One measures well in the electronics but doesn't measure well at the listening window. The other doesn't measure as well in the electronics but measures well at the listening window.

 

[Robh3606]

Nope. Both are measured. One measures well in the electronics but doesn't measure well at the listening window. The other doesn't measure as well in the electronics but measures well at the listening window.

I quess you got the speakers right for one and not the other.

Rob

 

[JackD201]

That would be part of it for sure Rob but not all of it

 

[Robh3606]

If you had a choice between a system with electronics that were true to something simple like a sine wave but the sound wasn't or a hodge podge of gear with bumps here and dips there but in the end sound in the listening window was like the test signal. What would you choose? This isn't a matter of preference. Which one is high fidelity?

Hello Jack

I would rather have what measures well and be damned with the listening window. There are way to many variables such as the speakers response, placement in the room and where you sit and so on. What you are talking about is highly unlikely. A solid state amplifier is not going to measure flat and suddenly have a 6db boost at 50hz as an example. With a tube amp you could get interaction with the speakers where it could potentially change to be fair going the other way. So it can happen where there are measureable interactions between paired components that could deviate from their previous "flat" set of individual measurements .

You ever do speaker measurements?? When you set-up you are essentially looking at the electronics as not having any significant effect. When you do a sine sweep and look at the distortion what you just measured is the entire chain not just the speaker. There is no way to get around it. No other way to make the measurement.

It all comes down to control and understanding what's hapening and why. A hodgepodge of lucky bumps can all be nullified by moving your listening chair 3 ft. So can a perfectly selected set of components. The difference is I know what I have with the good measuring gear.

So my final answer is both systems are not High Fidelity. They are both broken. IMHO It should both measure and sound good.

Rob

 

[JackD201]

Hello Jack

I would rather have what measures well and be damned with the listening window. There are way to many variables such as the speakers response, placement in the room and where you sit and so on. What you are talking about is highly unlikely. A solid state amplifier is not going to measure flat and suddenly have a 6db boost at 50hz as an example. With a tube amp you could get interaction with the speakers where it could potentially change to be fair going the other way. So it can happen where there are measureable interactions between paired components that could deviate from their previous "flat" set of individual measurements .

You ever do speaker measurements?? When you set-up you are essentially looking at the electronics as not having any significant effect. When you do a sine sweep and look at the distortion what you just measured is the entire chain not just the speaker. There is no way to get around it. No other way to make the measurement.

It all comes down to control and understanding what's hapening and why. A hodgepodge of lucky bumps can all be nullified by moving your listening chair 3 ft. So can a perfectly selected set of components. The difference is I know what I have with the good measuring gear.

So my final answer is both systems are not High Fidelity. They are both broken. IMHO It should both measure and sound good.

Rob

We agree way more than you think Rob. I just want to get a handle on Tim's perspective not prove anybody right or wrong. I will comment when he answers

 

[fas42]

Rob, I would be interested in your experiences, and take, on the best way to measure the the harmonic, and other non-linear distortion of speakers. As you say, when you measure you are always measuring the entire system at that moment, so how would you suggest separating out the distortion of the source and amp, and the distortion of the measuring mic?

Frank

 

[Phelonious Ponk]

Nope. Both are measured. One measures well in the electronics but doesn't measure well at the listening window. The other doesn't measure as well in the electronics but measures well at the listening window.

"Listening window" = speakers/room? If I had a signal chain that measured very well (and very thoroughly), was made up of compatible components, ended in an amplifier that was well-matched to the speakers and didn't measure well in-room, I would look for problems with the room and the speakers. If I had a signal chain that measured poorly enough to create audible problems and measured well in-room, I would look for problems with the measurements. I think I'm still not at all sure what you're driving at.

Tim

 

[Robh3606]

Rob, I would be interested in your experiences, and take, on the best way to measure the the harmonic, and other non-linear distortion of speakers. As you say, when you measure you are always measuring the entire system at that moment, so how would you suggest separating out the distortion of the source and amp, and the distortion of the measuring mic?

Hello Frank

Well that's not my focus so I don't give it much weight. You have to remember I am doing this for recreation and I am an amateur. The reason for the measurements is to build speakers, I am looking for accurate and repeatable and not concerned with the ultimate noise floor or whats lurking 40db down.

Sure I look at it and as long as it looks reasonable I don't look harder. For me accuracy is what's needed as eventually the measurements end up crossover simulation software. I use LEAP and it seems it's only limitation is what you feed it. I take double measurement set's both Sine and Impulse and compare them to make sure all is well. When the set-up right they really do mirror each other.

It would actually be quite easy to measure the loop without a speaker just using a load. That's not having the amp driving a real world load but that would at least give you a good idea of how much it would be contributing to the THD as a whole or use FFT to look at the noise spectrum.

Hey just for fun here's a compression driver measured on a waveguide no crossover. It's at 100db but remember compression drivers are very sensitive so the actual power is well under a watt. FR is Green the THD is Purple, the Red is the 2nd. Obviously the biggest component. 3rds not shown but the 4th and 5th are as Orange and Blue. Those a smoothed curves to make it easier to see where the average numbers are. So 2nd 3rd are about 40db down and the real grunge about another 10-20dB. Don't take these measurements to the bank

Rob

 

[fas42]

Thanks, Rob. So the 2nd harmonic dominates there, just like a good SET amp -- should sound fabulous on that point!

And apart from that the really unpleasant stuff is getting to be up to 60dB down: why, it could even be listenable to -- oh dear!

You wouldn't like to share where you're getting this data from: nudge, nudge, wink, wink ... :b

Frank

 

[Robh3606]

You wouldn't like to share where you're getting this data from: nudge, nudge, wink, wink ...

Hello Frank

That's my measurement. I took it 5 years ago when I was pair matching compression drivers for a speaker build. Another Python Fan good man!

Rob

 

[fas42]

I would just throw in another thought, because it was mentioned in a related way on another thread. The words "relentless" and "smooth", and their equivalents, come up again and again and again. With the usual take that getting relentless was bad, even though there was lots of detail and other good stuff, so one had to get back to the smooth.

All my experience, over and over again, has been other: relentless means you're going in the right direction; that you're almost there and need to persist. If you lose courage, so to speak, and back off, then you'll lose the important gains that were made, and it's highly likely you'll go this process yet again, and again, but coming from other directions. There is a hill, a hurdle that has to be passed over and if you don't then you'll never get to the next stage ...

Anyway, for what it's worth, that's been my journey ...

Frank

 

[JackD201]

@Tim

What I'm driving at is simple Tim. Assembling a bunch of top notch, and by that I don't mean exotic or expensive equipment, is no guarantee of accurate performance or pleasing performance for that matter. All it might do is give you a better starting point. You'd end up working the speakers into the room anyway and it doesn't matter if it's on a desktop or a dedicated, professionally acoustically engineered room to conform with your prioritized requirements as dictated by purpose and <<<<GASP>>>> the preferences that follow that. I know this, I know you know this.

I just want to know whether the end result is more important to you than the specs and measurements provided that you and I, in truth, have to take on blind faith as we have neither the skill, time or the resources to verify them. Faith based on nothing more than a company's reputation or that of the independent facility that did the measurements. That my friend is not so far removed from taking on faith the subjective quality based on brand. I don't think it's removed at all! What we do have tools for and for not much time and money is a slew of available test recordings, in-room measurement software and tools that no longer cost an arm and a leg. It is just disturbing when you and others keep drumming up this notion of accuracy and for goodness sake use the word "truth" when no one on this planet has seen or heard a signal in it's actual form to definitively say what came in is what came out. We're left with measurements and what we hear, which includes knolledge removed, both HIGHLY subject to interpretation.

So I ask again more pointedly this time. Even if the components are not "accurate" by themselves but the final output where it counts, the listening window, is a reasonably close to the test tone does this mean that just because the components of the system have deviations the sum of it's parts are not accurate? Will you disqualify a system as having a high level of fidelity just because there are parts, not the whole, that deviate?