HiFi - Facts, Fiction and Conjecture

[Ajani]

There is a lot of misinformation in our hobby and it's not quite as one way as it might seem.

For example, are following 3 statements fact, fiction or conjecture?

1) All amplifiers sound the same.

2) Tube amps are popular because they distort the sound in a pleasant manner.

3) All cables sound the same.

None of those statements are facts. 1 & 3 are straight up fiction and 2 is conjecture. It's easy to either completely misinterpret the results of DBT(double blind testing) and measurements or to draw conclusions that aren't actually proven.

The facts are that in DBT, no one has been able to prove that level matched amps, that measure the same, sound different. That is is a very different proposition from "all amps sound the same". It tells you that under certain conditions amps may sound different. First, if they're not level matched; even a relatively small increase in volume can make one amp sound better than the other. Secondly if the amps measure differently. So don't make the assumption that you can randomly pick the cheapest amp off the shelf and it will sound the same as the $15K one in the HiFi store. Just look at reviews that actually measure products and you might be surprised at how differently some products measure. Note that many expensive products measure terribly, so price is not a great indicator of quality/competent design.

Likewise, tube amps tend to measure poorly compared to solid state amps, but that doesn't prove that the only difference between the two is distortion. To provide compelling (though not absolute) proof of that, someone would need to design SS amps to directly mimic the distortion of various tube amps and then do DBT to see if the tube fans can tell the differences. This would be similar to the Carver Test (but a lot more rigorous).

Cables are similar to amps. They have to meet basic specifications to be "expected" to sound the same. For example, running 50 feet of 18 gauge speaker wire for a 4 ohm load probably isn't the best idea.

What all this means, is that when someone claims they heard a difference between amps or even speaker cables, you can't just assume that it was all in their imagination, as there may well be measurable reasons for the differences.

 

[jmjones]

Hi Ajani,

You just like creating 300 post threads don't you? Anyway, I enjoyed the last one, so here goes:

1.) I don't believe that to be true, but the only time I can say that I've really tested it is when I've been upgrading. I'm one of those people who refuses to buy anything unless I've heard the direct comparison (I attribute my bad back to carrying Kef 104ab's to dealers for speaker trials). In my earlier days I went through several amplifiers from Sansui, two from Audiolab, a Yamaha add-on and eventually settled on Tag McLaren. As I went on, my perception is that the law of diminishing returns bit with a vengeance. Moving from a 15 watt Sansui to a model with 80 watts and swanky meters made a hell of a difference. Moving from a good Audiolab pre-power to a Tag, not so much (and I'm happy admitting my bias for a single remote control drove a big money solution!!). I discarded several other amplifiers in trials en-route, on the basis of my opinion on their sound. My choice of amps tells you something about my musical preferences, although I expect someone in this thread to tell me it was expectation bias.

2.) No proper comparative evidence, but I've heard a lot of them at demos, dealers and friends to believe there is an audible difference when using valve amps. I have no vested interest here, as I've discounted valve amps for all sorts of other reasons in the past. Spent a fair amount of time listening to a friend's Sondek and mono Quad amps driving some giant TDL/IMFs (my age, I forget). "Warm Thunder" would be my summary. The rig was not for me, but I can see why he liked it. Did they measure the same against my solid state amps? Probably not.

3.) A qualified yes, but only because of a single example. I believe that removing the bell-wire speaker cable from my early system gave me one of the best value upgrades I ever made. On interconnects, I'm more sceptical - I tried a variety of RCA and digital cables. The complexity of the systems I have had (did I mention the tape decks, tuners, CD recorders, etc. No? Aha.) meant that I had a lot of "decent" cables and I have tried switching them around. No difference I could detect. I've settled on buying things that are shielded and don't cost a fortune (£50 tops) as a result.

I'm in agreement with you in principle. There are some differences to be heard, but why are they there? Over to the thread.

Regards, Mark

 

[Vladimir]

1W Class A > 1W Class AB > 1W Class D

 

[jmjones]

Hi Vlad,

The point being volume level would vary and some are better at heating the house? Would you expect different audible effects other than relative volume?

 

[Vladimir]

1oz of iron, 1oz of cotton or 1oz of lead?

 

[jmjones]

Here's me considering input not output. Dim. No difference for you then?

 

[Covenanter]

1) No but the differences are often exaggerated.

2) Different circuit designs bring different types of distortion. Distortion levels in most modern SS amplifiers will be very low (as long as they aren't clipping). Valve circuits tend to bring even order harmonic distortion which is said to be euphonious but this may be more to do with the listener than the amplifier.

3) No but if the cables are well made and suitable for the situation they are used in then any differences will be minimal.

Chris

 

[drummerman]

1. No

2. No

3. No

Imho

 

[Frank Harvey]

As others have said - no to all three - in my opinion.

 

[Vladimir]

Amplifiers, digital sources and cables all sound the same if well designed.

If this forum hears that acronym "DBT" once again, everyone will be buying a caravan ASAP.

 

[emperor's new clothes]

1oz of iron, 1oz of cotton or 1oz of lead?

Another trick question Vlad as weight is a force and oz a unit of mass?

 

[Vladimir]

1oz of iron, 1oz of cotton or 1oz of lead?

Another trick question Vlad as weight is a force and oz a unit of mass?

F=ma

Weight is mass, not force. You need to add acceleration to get force out of mass.

 

[chebby]

Not all amps sound the same. Some are tweaked to sound like old Leak valve amps ...

http://www.the-ear.net/features/terry-bateman-tells-story-rega-brio-r

http://www.hi-fiworld.co.uk/index.php/letters/579-february-2013-issue.html?start=1

 

[andyjm]

1oz of iron, 1oz of cotton or 1oz of lead?

Another trick question Vlad as weight is a force and oz a unit of mass?

F=ma

Weight is mass, not force. You need to *add acceleration to get force out of mass.

* multiply by...

The respective weight of the iron, cotton and lead and the mass of the iron, cotton and lead are the same in your example. The weight is of course = 9.8 * mass (in SI units - no idea what an oz is..) in all cases.

 

[Vladimir]

1oz of iron, 1oz of cotton or 1oz of lead?

Another trick question Vlad as weight is a force and oz a unit of mass?

F=ma

Weight is mass, not force. You need to *add acceleration to get force out of mass.

* multiply by...

The respective weight of the iron, cotton and lead and the mass of the iron, cotton and lead are the same in your example. The weight is of course = 9.8 * mass (in SI units - no idea what an oz is..) in all cases.

Thank you for the correction.

oz - ounce.

So which watt is more powerfull? Class A, B or D?

 

[andyjm]

1oz of iron, 1oz of cotton or 1oz of lead?

Another trick question Vlad as weight is a force and oz a unit of mass?

F=ma

Weight is mass, not force. You need to *add acceleration to get force out of mass.

* multiply by...

The respective weight of the iron, cotton and lead and the mass of the iron, cotton and lead are the same in your example. The weight is of course = 9.8 * mass (in SI units - no idea what an oz is..) in all cases.

Thank you for the correction.

oz - ounce.

So which watt is more powerfull? Class A, B or D?

An interesting question. 1 watt of input power to a class A could result in no output at all (but a slightly warmer room), at least with class B you might get something out of the speakers for 1 watt of input power, and class D will pass most of your 1 watt onto the speakers. So I am going with class D.

 

[Vladimir]

Will 1W out of Class A biased amp sound 'more powerful' than 1W out of Class B or D?

Will 1W out of Class A biased amp sound 'more powerful' than 1W out of Class B or D in 8 ohms?

Will 1W out of Class A biased amp sound 'more powerful' than 1W out of Class B or D in 4 ohms?

 

[drummerman]

1oz of iron, 1oz of cotton or 1oz of lead?

Another trick question Vlad as weight is a force and oz a unit of mass?

F=ma

Weight is mass, not force. You need to *add acceleration to get force out of mass.

* multiply by...

The respective weight of the iron, cotton and lead and the mass of the iron, cotton and lead are the same in your example. The weight is of course = 9.8 * mass (in SI units - no idea what an oz is..) in all cases.

Thank you for the correction.

oz - ounce.

So which watt is more powerfull? Class A, B or D?

An interesting question. 1 watt of input power to a class A could result in no output at all (but a slightly warmer room), at least with class B you might get something out of the speakers for 1 watt of input power, and class D will pass most of your 1 watt onto the speakers. So I am going with class D.

Am I missing something?

1 watt of continuous average power measured at the speaker terminal (or amplifier output) surely is exactly the same power regardless of topology, no?

 

[andyjm]

1oz of iron, 1oz of cotton or 1oz of lead?

Another trick question Vlad as weight is a force and oz a unit of mass?

F=ma

Weight is mass, not force. You need to *add acceleration to get force out of mass.

* multiply by...

The respective weight of the iron, cotton and lead and the mass of the iron, cotton and lead are the same in your example. The weight is of course = 9.8 * mass (in SI units - no idea what an oz is..) in all cases.

Thank you for the correction.

oz - ounce.

So which watt is more powerfull? Class A, B or D?

An interesting question. 1 watt of input power to a class A could result in no output at all (but a slightly warmer room), at least with class B you might get something out of the speakers for 1 watt of input power, and class D will pass most of your 1 watt onto the speakers. So I am going with class D.

Am I missing something?

1 watt of continuous average power measured at the speaker terminal (or amplifier output) surely is exactly the same power regardless of topology, no?

You are missing nothing - except perhaps the word 'input' in my post.

 

[drummerman]

1oz of iron, 1oz of cotton or 1oz of lead?

Another trick question Vlad as weight is a force and oz a unit of mass?

F=ma

Weight is mass, not force. You need to *add acceleration to get force out of mass.

* multiply by...

The respective weight of the iron, cotton and lead and the mass of the iron, cotton and lead are the same in your example. The weight is of course = 9.8 * mass (in SI units - no idea what an oz is..) in all cases.

Thank you for the correction.

oz - ounce.

So which watt is more powerfull? Class A, B or D?

An interesting question. 1 watt of input power to a class A could result in no output at all (but a slightly warmer room), at least with class B you might get something out of the speakers for 1 watt of input power, and class D will pass most of your 1 watt onto the speakers. So I am going with class D.

Am I missing something?

1 watt of continuous average power measured at the speaker terminal (or amplifier output) surely is exactly the same power regardless of topology, no?

You are missing nothing - except perhaps the word 'input' in my post.

The resulting sound of this one watt average continuoued power at the output could well be perceived differently depending on topology or even design of the same topology, even cables.

 

[Ajani]

Hi Ajani,

You just like creating 300 post threads don't you?

Actually, I'd be really surprised if this thread gets anywhere close to that kind of activity. My last thread was really an opinion piece, so it should be a lot more debatable and controversial.

Anyway, I enjoyed the last one, so here goes:
1.) I don't believe that to be true, but the only time I can say that I've really tested it is when I've been upgrading. I'm one of those people who refuses to buy anything unless I've heard the direct comparison (I attribute my bad back to carrying Kef 104ab's to dealers for speaker trials). In my earlier days I went through several amplifiers from Sansui, two from Audiolab, a Yamaha add-on and eventually settled on Tag McLaren. As I went on, my perception is that the law of diminishing returns bit with a vengeance. Moving from a 15 watt Sansui to a model with 80 watts and swanky meters made a hell of a difference. Moving from a good Audiolab pre-power to a Tag, not so much (and I'm happy admitting my bias for a single remote control drove a big money solution!!). I discarded several other amplifiers in trials en-route, on the basis of my opinion on their sound. My choice of amps tells you something about my musical preferences, although I expect someone in this thread to tell me it was expectation bias.

2.) No proper comparative evidence, but I've heard a lot of them at demos, dealers and friends to believe there is an audible difference when using valve amps. I have no vested interest here, as I've discounted valve amps for all sorts of other reasons in the past. Spent a fair amount of time listening to a friend's Sondek and mono Quad amps driving some giant TDL/IMFs (my age, I forget). "Warm Thunder" would be my summary. The rig was not for me, but I can see why he liked it. Did they measure the same against my solid state amps? Probably not.

3.) A qualified yes, but only because of a single example. I believe that removing the bell-wire speaker cable from my early system gave me one of the best value upgrades I ever made. On interconnects, I'm more sceptical - I tried a variety of RCA and digital cables. The complexity of the systems I have had (did I mention the tape decks, tuners, CD recorders, etc. No? Aha.) meant that I had a lot of "decent" cables and I have tried switching them around. No difference I could detect. I've settled on buying things that are shielded and don't cost a fortune (£50 tops) as a result.

I'm in agreement with you in principle. There are some differences to be heard, but why are they there? Over to the thread.

Regards, Mark

Now that is the essential question, and I hope to live long enough to see science answer it definitively.

My interpretation of what the science shows at this stage, is that the differences claimed by audiophiles (that are not easily explained by measurements, volume differences etc) are very subtle or possibly even imagined. But even subtle differences might increase someone's sonic enjoyment in the long run.

Where I think knowing the reasons for the differences really helps, is when you are determing how to spend your money. I'm not going to spend a large percentage of my budget on very subtle differences. I'd rather spend it on areas I know will have a strong impact on the sound quality.

 

[jmjones]

Question - and I don't know the answer to this, but I think I'm building on the Drummerman's logic. The watts are the same, but information is being transmitted and it's an analogue signal.

Using Vlad's example - an ounce of iron, cotton and feathers may weigh the same, but when you make something of them they are very different. Try some sculpture. Anyway, make a projectile of them and shoot me with it if you like - I'll take the cotton. In Vlad's example of a well designed amplifier the only difference would probably be THD? Or is there anything anything else?

And just to be a smart alec - my weight is force. It is my mass accelerated by the Earth's gravity. In space I weigh nothing, but my mass has not changed. It's possible ounces were invented before anyone decided we needed to know the difference!!

 

[Vladimir]

1W = 1W = 1W regardless of output stage biasing, that was my point. How you percieve it doesn't change the fact that an amplifier will begin clipping after it excedes it's power output capabilities.

Let's say you want to prop up a desk with a couple of books. What matters is how thicks they are, not if they are poetry or phonebooks.

There is a threshold in amplifiers where further qualitative improvements in performance stop being audible. Same is for DACs and CDPs. Same for cables. Fortunately components that pass this sonic quality barier are cheap and plentiful. You can pay premium for added features, better build quality, aesthetics and larger quantity, but you won't get improved sound quality out of it. You can imagine it if it pleases you, but it's not real.

 

[Snooker]

This again like my previous thread is just my opinion, its just I do get a little passionate about it at times

I believe that power leads, and if a power supply transformer is wound by hand or machine will make no audiable difference at all, as the alternating voltage is changed into a direct voltage and most importantly the now 100hz ripple is then smoothed by a big capacitor and then fed to a regulator, so that the direct voltage is as smooth as can be without any audiable ripples, this I believe is science fact in this case

 

[Snooker]

1W = 1W = 1W regardless of output stage biasing, that was my point. How you percieve it doesn't change the fact that an amplifier will begin clipping after it excedes it's power output capabilities.

Let's say you want to prop up a desk with a couple of books. What matters is how thicks they are, not if they are poetry or phonebooks.

There is a threshold in amplifiers where further qualitative improvements in performance stop being audible. Same is for DACs and CDPs. Same for cables. Fortunately components that pass this sonic quality barier are cheap and plentiful. You can pay premium for added features, better build quality, aesthetics and larger quantity, but you won't get improved sound quality out of it. You can imagine it if it pleases you, but it's not real.

This is what I have been saying in my recent thread, and I believe the threshold is around a £2000 system which is very well and carefully matched, although others may think the threshold value is different