You are free to think what you want. What's even better is if it's accompanied by factual evidence.
Thank You 😉
Forums | The Absolute Sound
and little more for double blind tests aficionados who feel better not spending money on equipment
http://www.audioholics.com/how-to-shop/revealing-flaws-in-the-loudspeaker-demo-double-blind-test
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and something else to consider
Are You On The Road To... Audio Hell? by Leonard Norwitz and Peter Qvortrup
Are You On The Road To... Audio Hell? by Leonard Norwitz and Peter Qvortrup
Don't thank me. Thank the founders of this nation.
Looks like you don't know what Robert Harley really is. Click on this evaluation of his work.
His critique about DBT with citing of Swedish Radio experiment has been used by anti-DBT audio crowds ever since he published it. The problem is, that Swedish Radio experiment wasn't really DBT. But that doesn't matter to anti-DBT audio crowds because Robert Harley sings the tune they want to hear. 🙄
You are no longer discussing amps anymore? That link talks about DBT of speakers. It even says, "DBTs are set up so that very small differences can be revealed.".
That online magazine sells ads and generates revenue through reviews of audio gears. Why should anyone in search of neutral info on electronics give credence to such site? They have to publish reviews positively even if it means bs-ing, otherwise the revenue generating opportunity will stop coming in. If you have time to dig through such site, read the textbook instead.
Push-Pull is better if done right. Low or no feedback sounds more relaxed (only possible with tubes). There is a topology that I discovered in a 1956ish Gibson guitar amp (GA-40T I think), that has virtually no crossover distortion even when jammed way into clipping. Most other topologies that I've looked at have substantial crossover distortion (due to what's called "blocking distortion) once they hit clipping. It's about how the phase splitter works. Just my opinion, but less than 25 watts rms is just not of interest to me. The best sounding speakers need at lest that to shine. Pumping up the lowest frequencies with active EQ is a huge plus IMO, and you can't really do that well with micro-power. If the crossover is active, SE might be OK for the tweeter.
We are discussing the DBT method not the amps anymore.From what I briefly read it is as flawed as any other testing method . I never considered DBT as any valuable tool for what in essence is an opinionated, men dominated hobby and I'm not into accuracy in your meaning of this term. If you sleep better knowing that your $199 Best Buy bought receiver performs on the same level like $5k Jeff Rowland that's perfectly fine with me. Everybody has to find a justification of their own actions or non actions . The examples I put here were first which came up from Google search to give a little bit of counterbalance for DBT militia offensive here. I don't care for Robert Harley or any other official audio critic.
I don't know the definition of an accurate amplifier designed to have no artifacts. I thought all of them , even the cheapest are advertised as such.Give me some reference models so I can relate to the field level we're playing.
Wait, I think I know . It's the one dr.Geddes is using in his HT . Did I win the prize?
I don't know the definition of an accurate amplifier designed to have no artifacts. I thought all of them , even the cheapest are advertised as such.Give me some reference models so I can relate to the field level we're playing.
Wait, I think I know . It's the one dr.Geddes is using in his HT . Did I win the prize?
Since which post?
You have probably read something written by those that are selling or advertizing high-end audio gears and want to discredit the results of DBT because it works against their marketing hypes about high-end price being audibly worth it.
You've never done a level matched DBT listening comparison so let me remind you of your own words (quoted below) again.
It's the other way around. Those who spent $5K on receiver or amp don't want to know or admit that they wasted their money for a gear that's audibly no better than $199 receiver.
You mean you had no knowledge base on what you were arguing about?
For starter, some sincerity can help you to move forward.
And what we're arguing about ?
Suitability of SET as an Audio Amplifier ?
Validity of DBT tests ?
The thesis that " amps designed to have no audible artefacts all sound the same"
whatever that amps are ?
Superiority of amps designed to have no audible artefacts ?
Superiority of $199 Costco receivers?
My sincerity ?
Did you test yourself for mental stability? Probably not , why?
There is no indication that you should.
Did I test myself with DBT? No, why ?
Never felt the need for it.
Am I eluding myself? Quite possible!
Would I rather own $199 Costco receiver ? NO thanks ! Rather not.
Is Costco receiver as bad as many $5k Solid State High End Amps? I bet it is . More , I'm pretty sure it is considering my experience with "artifacts free arteficial" SS amps.
Do I want to move forward and test myself with DBT ? I may consider it when opportunity arrives but will not actively seek it out.
Let me know if you have more questions.
Rgrds, L
Oh , I almost forgot
Did my ex won every and all arguments we ever had ? Yes unfortunately she did ..
Suitability of SET as an Audio Amplifier ?
Validity of DBT tests ?
The thesis that " amps designed to have no audible artefacts all sound the same"
whatever that amps are ?
Superiority of amps designed to have no audible artefacts ?
Superiority of $199 Costco receivers?
My sincerity ?
Did you test yourself for mental stability? Probably not , why?
There is no indication that you should.
Did I test myself with DBT? No, why ?
Never felt the need for it.
Am I eluding myself? Quite possible!
Would I rather own $199 Costco receiver ? NO thanks ! Rather not.
Is Costco receiver as bad as many $5k Solid State High End Amps? I bet it is . More , I'm pretty sure it is considering my experience with "artifacts free arteficial" SS amps.
Do I want to move forward and test myself with DBT ? I may consider it when opportunity arrives but will not actively seek it out.
Let me know if you have more questions.
Rgrds, L
Oh , I almost forgot
Did my ex won every and all arguments we ever had ? Yes unfortunately she did ..
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One should always be suspicious of people with something to lose (in this case the purveyors and reviewers of the "high-end" audio market) when they attack measurements that expose the hollowness of their claims. In the words of the late Mandy Rice-Davies, "they would, wouldn't they?"
It is reminiscent of the arguments used by spoon-benders, telekineticists and other charlatans when scientific testing fails to confirm their alleged abilities.
Chris
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Are there people making claims that DBT methodology is flawed? Sure lots.
Are there studies published in the scientific journals that suggest that DBT methodology is flawed? No.
Now what is a sceptical person to think....
Are there studies published in the scientific journals that suggest that DBT methodology is flawed? No.
Now what is a sceptical person to think....
Do you have a problem with a hobby which mainly attracts men? In what sense do men 'dominate' audio? Is it because serious audio people (of any gender) try to insist on facts rather than unsubstantiated opinions? (At this point I am very tempted to answer a sexist comment with another sexist comment, but I will resist the temptation.)limono said:
Do you have your own private definition of accuracy? If so, please share it with us as this will aid communication.
DBT is simply a way to ensure that 'ears only' claims are subjected to 'ears only' testing. Curiously, results of most (but not all) such tests seem to confirm that things which should be heard (according to science) can be heard, and things which should not be heard are not heard. This consistency is regarded as the norm in science, but of course critics will dismiss it as merely a consequence of male hegemony and the gendered assumptions of Newtonian/Maxwellian physics.
mankind has great tech advancement, compared to many years ago.
but still no signs of amplifying device with minimal distortion and schoolbook linearity
but still no signs of amplifying device with minimal distortion and schoolbook linearity
You bring back fond memories of an early childhood spent poring over Giles cartoons showing quivering Tory politicians hiding under tables, and never quite understanding why ...
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A good single ended triode, such as the 6SN7, has about as good a harmonic distortion spectrum as it gets. The products roll off fairly quickly, and the 2nd dominates the third. A push-pull circuit that is linearized and perfectly balanced with negative feedback, driven with a perfectly balanced phase splitter will have a supressed even harmonic distortion spectrum. That doesn't sound as good (natural - consistent with how the ear distorts). However, if the drive signals are unbalanced by only one dB, the distortion spectrum went back to looking like a single ended triode. This was with no negative feedback. So I designed my Hi-Fi tube amp to have just enough negative feedback to be able to present a reasonable output impedance to the reactive speakers (below an ohm), but not enough to make the circuit perfectly balanced.
The other issue with Push-pull is the crossover distortion, which can cause distortion products that are way higher in frequency than anything in the music content. I bias my EL34's at 40mA quiescent, so crossover distortion is very unlikely to have any effect. If you bias them too low, especially low level signals will suffer badly.
Bottom line, push-pull is great if done right.
The other issue with Push-pull is the crossover distortion, which can cause distortion products that are way higher in frequency than anything in the music content. I bias my EL34's at 40mA quiescent, so crossover distortion is very unlikely to have any effect. If you bias them too low, especially low level signals will suffer badly.
Bottom line, push-pull is great if done right.
Unforch, this is all too true.
There is no reason SS has to sound as bad as it does. Getting an SS amp sounding good isn't as easy, but it can be done, and I design both. Getting the good results means going against convention, as always. I've gotten some excellent results.
Some of the problems are the increasing rarity of power transistors for audio. These days, you have a whole bunch of MOSFETs designed for switching applications, not linear amplification. VFETs and lateral MOSFETs have gone the way of Western Electric 300Bs: very rare, very $$$$$, and often counterfeited. Some devices, such as IGBTs, just will never sound any good regardless of what you do. Save 'em for switching projects.
Bad topologies and bad devices make for soundbad. Always have; always will. It doesn't have to be that way.
Regarding DBT and Science
It could be that :
-Participants of that kind of test are usually clueless about audio and never developed any conscious comparative method. The have hard time telling clarinet from sax,or violin from viola but are eager to test themselves .The results are easy to predict I.E all sound the same
-Participants never really experienced High-End amplification at their on homes ,they are just show going / forum trolling experts . If the difference doesn't hit them in between the eye they are not able to react to more subtle clues
-Participants are DIY minded individuals who have deeply rooted conviction and agenda that the difference doesn't exist and all High-End is a scam devised to part suckers and their money , they can't help it even if they try and push the button randomly
- Everybody loves underdogs and it would be really nice if the High End component was knocked out by a DIY/ Costco/ black box .Nobody can help it ,m it's reality
-Every test is a stress no matter how relaxed and familiar atmosphere.
It could be that :
-Participants of that kind of test are usually clueless about audio and never developed any conscious comparative method. The have hard time telling clarinet from sax,or violin from viola but are eager to test themselves .The results are easy to predict I.E all sound the same
-Participants never really experienced High-End amplification at their on homes ,they are just show going / forum trolling experts . If the difference doesn't hit them in between the eye they are not able to react to more subtle clues
-Participants are DIY minded individuals who have deeply rooted conviction and agenda that the difference doesn't exist and all High-End is a scam devised to part suckers and their money , they can't help it even if they try and push the button randomly
- Everybody loves underdogs and it would be really nice if the High End component was knocked out by a DIY/ Costco/ black box .Nobody can help it ,m it's reality
-Every test is a stress no matter how relaxed and familiar atmosphere.
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