[esldude]

Just out of interest, are you going to perform an ear test (using headphones)?

Well the person who supplied the one in photos listened to it before doing so.  Presumably the person who is supplying the one being measured did so.  And no reason an ear test can't be done. 
 
Now you asked what will the test show.  I expect they will test frequency response, distortion, and noise over up to 20 khz.  They may do more than this.  If the results are the same with or without the device it does nothing audible.  They may also do a null test, but I'll say no more as I am not the one doing the testing. 
 
Now you are wondering why not a listening test just to see.  For one thing, if a device measures the same on all the above tests it has been found to sound the same.  Lots of claims different, but they just don't pan out.
 
Now another issue is people are just prone to hear a difference on the flimsiest excuse.  Not that they are making it up or aware of what is happening.  Some fair number of people just knowing they plugged something in may honestly try to see if it sounds different and find that it does.  Even when there is no reason for it. They are even more likely to have the experience of hearing a difference if someone has primed them to expect a difference.
 
The way to deal with that is blind testing.  Someone plugs in and alternately bypasses the device while another person listens and says whether the sound is different or not.  Devices that measure the same, but people listen to and swear how real the difference is turn out not to be discerned when the listening comparison is done blind.
 
It is good to be aware of how easily your ears/mind will trick you when you know something has been changed.  It happens to everyone, and no one is totally immune from it no matter how hard they try.  Very hard to get many to believe this.  Hey, why are you so close minded they say, just listen for yourself and see. Such a situation anyone is very likely to listen and hear a difference that is not really there.  Just trying something out to see what you think seems so simple.
 
Now if the differences are large, then yes you can actually hear something is different with a more casual approach (though matching levels is important even here).  But anything so easily detected with sighted listening will measure obviously different.  The tricky issue is differences get small enough our ears may get tricked well before measured differences get too small to be detected.  By then your brain is likely to grab hold of nearly anything and match a pattern to hear a difference even when there is no difference. 

 

[SilentFrequency]

Well the person who supplied the one in photos listened to it before doing so.  Presumably the person who is supplying the one being measured did so.  And no reason an ear test can't be done. 

Now you asked what will the test show.  I expect they will test frequency response, distortion, and noise over up to 20 khz.  They may do more than this.  If the results are the same with or without the device it does nothing audible.  They may also do a null test, but I'll say no more as I am not the one doing the testing. 

Now you are wondering why not a listening test just to see.  For one thing, if a device measures the same on all the above tests it has been found to sound the same.  Lots of claims different, but they just don't pan out.

Now another issue is people are just prone to hear a difference on the flimsiest excuse.  Not that they are making it up or aware of what is happening.  Some fair number of people just knowing they plugged something in may honestly try to see if it sounds different and find that it does.  Even when there is no reason for it. They are even more likely to have the experience of hearing a difference if someone has primed them to expect a difference.

The way to deal with that is blind testing.  Someone plugs in and alternately bypasses the device while another person listens and says whether the sound is different or not.  Devices that measure the same, but people listen to and swear how real the difference is turn out not to be discerned when the listening comparison is done blind.

It is good to be aware of how easily your ears/mind will trick you when you know something has been changed.  It happens to everyone, and no one is totally immune from it no matter how hard they try.  Very hard to get many to believe this.  Hey, why are you so close minded they say, just listen for yourself and see. Such a situation anyone is very likely to listen and hear a difference that is not really there.  Just trying something out to see what you think seems so simple.

Now if the differences are large, then yes you can actually hear something is different with a more casual approach (though matching levels is important even here).  But anything so easily detected with sighted listening will measure obviously different.  The tricky issue is differences get small enough our ears may get tricked well before measured differences get too small to be detected.  By then your brain is likely to grab hold of nearly anything and match a pattern to hear a difference even when there is no difference. 

That's actually really interesting and I didn't realise the psychological aspect involved at the level you describe, it's just intense!

I guess I understand the values of the electrical testing much better now as the organic human aspect of testing when subtleties can be potentially cause false positives if I'm understanding fully.

But what is a null test you mentioned?

 

[Head Injury]

That's actually really interesting and I didn't realise the psychological aspect involved at the level you describe, it's just intense!

I guess I understand the values of the electrical testing much better now as the organic human aspect of testing when subtleties can be potentially cause false positives if I'm understanding fully.

But what is a null test you mentioned?

A null test takes one signal and subtracts it from another to leave just the differences (it "nulls" or zeroes everything that's the same). In this case, the tester would loop the signal from the DAC back into an ADC, or even all the way through headphones and a microphone too, and record the signal, then do the same thing with the HOT in the chain. After the non-HOT loop is subtracted from the HOT loop, anything the HOT does to the signal will be left and can be tested for volume level, frequency response, etc.

 

[Steve Eddy]

But what is a null test you mentioned?

A null test is where you take two signals, one which has passed through the device under test, and the other signal without having passed through the device under test. Then you differentiate, or subtract them. What you're left with is a residual signal that is the difference between the device under test and the bypass.

If the residual signal isn't audible, then the device under test isn't changing the signal in any audible way.

se

 

[smial1966]

OK, time to confess.

I'm the gullible schmuck that purchased the HOT that Steve Eddy now has for testing. Being a perennial tweaker audio gadgets intrigue my Luddite mind and I've circumbed to many whacky tips over the years. Yes, I have frozen CD's and green inked their circumferences, stuck Black-Tac on my listening room walls and even purchased a "Sonic Plate" hewn from bell brass. All of the aforementioned nonsense cost relatively little and were not promoted by a supposedly reputable company.

In a moment of abject madness I stumped up $300 for the HOT from a stateside dealer. When it arrived I eagerly plugged it into my ECP headphone amp, donned my HD650 and awaited the amazing holographic soundstage promised. But oh dear, what the feck?!? The sound was decidedly muffled and devoid of treble extension. Assuming a product 'burn in' period I persevered and left my rig playing for 24 hours. Yeah that helped not one iota. The sound was mushy, coalesced and quite frankly awful.

People the HOT is a snake oil product borne of quackery and sold to chumps who've had a momentary loss of rationality.

Please don't judge me too harshly as I've finally learnt the error of my tweaking ways!

Cheers,
Andy.

Well the person who supplied the one in photos listened to it before doing so.  Presumably the person who is supplying the one being measured did so.  And no reason an ear test can't be done. 

Now you asked what will the test show.  I expect they will test frequency response, distortion, and noise over up to 20 khz.  They may do more than this.  If the results are the same with or without the device it does nothing audible.  They may also do a null test, but I'll say no more as I am not the one doing the testing. 

Now you are wondering why not a listening test just to see.  For one thing, if a device measures the same on all the above tests it has been found to sound the same.  Lots of claims different, but they just don't pan out.

Now another issue is people are just prone to hear a difference on the flimsiest excuse.  Not that they are making it up or aware of what is happening.  Some fair number of people just knowing they plugged something in may honestly try to see if it sounds different and find that it does.  Even when there is no reason for it. They are even more likely to have the experience of hearing a difference if someone has primed them to expect a difference.

The way to deal with that is blind testing.  Someone plugs in and alternately bypasses the device while another person listens and says whether the sound is different or not.  Devices that measure the same, but people listen to and swear how real the difference is turn out not to be discerned when the listening comparison is done blind.

It is good to be aware of how easily your ears/mind will trick you when you know something has been changed.  It happens to everyone, and no one is totally immune from it no matter how hard they try.  Very hard to get many to believe this.  Hey, why are you so close minded they say, just listen for yourself and see. Such a situation anyone is very likely to listen and hear a difference that is not really there.  Just trying something out to see what you think seems so simple.

Now if the differences are large, then yes you can actually hear something is different with a more casual approach (though matching levels is important even here).  But anything so easily detected with sighted listening will measure obviously different.  The tricky issue is differences get small enough our ears may get tricked well before measured differences get too small to be detected.  By then your brain is likely to grab hold of nearly anything and match a pattern to hear a difference even when there is no difference. 

 

[SilentFrequency]

A null test takes one signal and subtracts it from another to leave just the differences (it "nulls" or zeroes everything that's the same). In this case, the tester would loop the signal from the DAC back into an ADC, or even all the way through headphones and a microphone too, and record the signal, then do the same thing with the HOT in the chain. After the non-HOT loop is subtracted from the HOT loop, anything the HOT does to the signal will be left and can be tested for volume level, frequency response, etc.

A null test is where you take two signals, one which has passed through the device under test, and the other signal without having passed through the device under test. Then you differentiate, or subtract them. What you're left with is a residual signal that is the difference between the device under test and the bypass.

If the residual signal isn't audible, then the device under test isn't changing the signal in any audible way.

se

Thank you both!

 

[SunTanScanMan]

OK, time to confess.

I'm the gullible schmuck that purchased the HOT that Steve Eddy now has for testing. Being a perennial tweaker audio gadgets intrigue my Luddite mind and I've circumbed to many whacky tips over the years. Yes, I have frozen CD's and green inked their circumferences, stuck Black-Tac on my listening room walls and even purchased a "Sonic Plate" hewn from bell brass. All of the aforementioned nonsense cost relatively little and were not promoted by a supposedly reputable company.

In a moment of abject madness I stumped up $300 for the HOT from a stateside dealer. Whenever it arrived I eagerly plugged it into my ECP headphone amp, donned my HD650 and awaited the amazing holographic soundstage promised. But oh dear, what the feck?!? The sound was decidedly muffled and devoid of treble extension. Assuming a product 'burn in' period I persevered and left my rig playing for 24 hours. Yeah that helped not one iota. The sound was mushy, coalesced and quite frankly awful.

People the HOT is a snake oil product borne of quackery and sold to chumps who've had a momentary loss of rationality.

Please don't judge me too harshly as I'vefinally learnt the error of my ways!

Cheers,
Andy.

Hey Andy thanks for donating the HOT for testing.
 
Could you clarify. Your message seems to imply that the HOT affected your HD650's sound negatively. Or did you feel that way about the Senns before the HOT?

 

[SilentFrequency]

OK, time to confess.

I'm the gullible schmuck that purchased the HOT that Steve Eddy now has for testing. Being a perennial tweaker audio gadgets intrigue my Luddite mind and I've circumbed to many whacky tips over the years. Yes, I have frozen CD's and green inked their circumferences, stuck Black-Tac on my listening room walls and even purchased a "Sonic Plate" hewn from bell brass. All of the aforementioned nonsense cost relatively little and were not promoted by a supposedly reputable company.

In a moment of abject madness I stumped up $300 for the HOT from a stateside dealer. Whenever it arrived I eagerly plugged it into my ECP headphone amp, donned my HD650 and awaited the amazing holographic soundstage promised. But oh dear, what the feck?!? The sound was decidedly muffled and devoid of treble extension. Assuming a product 'burn in' period I persevered and left my rig playing for 24 hours. Yeah that helped not one iota. The sound was mushy, coalesced and quite frankly awful.

People the HOT is a snake oil product borne of quackery and sold to chumps who've had a momentary loss of rationality.

Please don't judge me too harshly as I'vefinally learnt the error of my ways!

Cheers,
Andy.

I really appreciate your honesty and am sure other members will also.

But I'm also sorry this device actually degraded your listening experience and am even more so shocked of this than if you had found it to have made no difference.

This entire thread is such an eye opener for me.

But thank you again for your comments and indeed providing your device for testing.

 

[Head Injury]

Please don't judge me too harshly as I'vefinally learnt the error of my ways!

I say losing $300 to some wire and quartz is punishment enough. Your loss will hopefully help others avoid a similar fate, we should be thanking you.

 

[smial1966]

The HOT has a muting effect on any headphones ability to reproduce frequency extremes and it especially diminishes treble reproduction. It's quite frankly bloody awful in my opinion.

Hey Andy thanks for donating the HOT for testing.

Could you clarify. Your message seems to imply that the HOT affected your HD650's sound negatively. Or did you feel that way about the Senns before the HOT?

 

[krismusic]

OK, time to confess.

I'm the gullible schmuck that purchased the HOT that Steve Eddy now has for testing. Being a perennial tweaker audio gadgets intrigue my Luddite mind and I've circumbed to many whacky tips over the years. Yes, I have frozen CD's and green inked their circumferences, stuck Black-Tac on my listening room walls and even purchased a "Sonic Plate" hewn from bell brass. All of the aforementioned nonsense cost relatively little and were not promoted by a supposedly reputable company.



Please don't judge me too harshly as I'vefinally learnt the error of my ways!

Cheers,
Andy.

Yup. I fell for the green ink. I spent many years and a reasonable amount of money trying to enjoy a speaker system. I spent several hundreds on cables.
It was here that I first heard about psychoacoustics. I now think that everything I thought I knew is placebo bias. Not just audio. The rest of my life too!
Seriously, I now have the 600's and a little O2 amp. Total cost about £330 running Spotify Premium through my iPhone and could not be happier with the sound. Job done. Still finding IEM's problematic mind!

 

[Steve Eddy]

Please don't judge me too harshly as I'vefinally learnt the error of my ways!

What do you think, guys? I think he's hopeless. We have the second HOT now, I say we burn him at the stake.

Thanks for coming forward, Andy. And thanks so much for your generosity.

As I said previously, I told Andy I would be happy to sell it once the electrical testing has been done and pay him back at least part of what he had spent on it. He declined and said that if I sold it, to give the funds to a homeless charity. So once the electrical testing has been done, I will sell it and donate 100% of the proceeds to Sacramento's Loaves & Fishes.

se

 

[SilentFrequency]

I say losing $300 to some wire and quartz is punishment enough. Your loss will hopefully help others avoid a similar fate, we should be thanking you.

Totally this! ^

 

[Billheiser]

Andy, you're a mensch!

 

[Steve Eddy]

Andy, you're a mensch!

Hey, no need to resort to name-calling.

se