John Curl's Blowtorch preamplifier

Status
Not open for further replies.
Jump to Latest
#18,861
No, it is in my professional interest to know where I stand in audio reality. IF I have heard better CD at CES shows using the SAME BLOWTORCH, then I know that MY CD reproduction is the problem. Perhaps, a VERY EXPENSIVE SONY would be OK, but I can't afford it either, and from modifying very expensive SONY equipment over the decades, I am reasonably sure the even the most expensive SONY equipment would require modification to get it right. If this were not so, we would use SONY as our reference sources at CES. We don't make CD players, so why should we care?
At the last CES, I heard a really nice CD playback with the LAMM tube system and a very expensive Wilson Audio speaker. I asked about it, and talked with an employee of the company, whose name was Jean-Francois Fronton, a manager representing ACOUSTIC PRECISION DIFFUSION. I would buy one, outright, if I could afford it. It was that good! Better than the pretty good vinyl playback that they also used.
This is how I operate: If it works, it works! If it doesn't, I don't say that I must be imagining that it doesn't work. That is what makes me effective, and I will continue to do so.
 
#18,862
john curl said:
I actually can tell the difference between a SONY and a BLOWTORCH.
I have a SONY SACD player attached to the BLOWTORCH, and every time that I play a CD, DVD, or SACD, I hear the difference. It is frustrating, because the rest of my equipment is first class. A vinyl record or even FM reproduction is better.
Click to expand...

John
This is interesting.
You actually mean that a FM radio sounds better than a SACD?

I guess is that as the source of the FM radio signals you will find a pretty normal CD player, so why would it sound better if it is modulated – demodulated?

Isn’t that strange?
 
#18,863
janneman said:



For direct comparison we can keep something like 8-10secs of sound in our direct memory. This is usefull if you do listening comparisons with simple sounds, you can switch between them fairly rapidly and you can be very sensitive to small differences.

The problem with more complex sounds like music is that there are many different attributes of that sound, like freq content, rythm, pace, melody, spaciousness, harmony, resolution, you name it, and we are not able to simultaneously keep track of all of them. So we need longer periods to become aware of all those attributes by focussing our attention on this one, then on that one. Then we must somehow try to decide that there is a difference or not. You can imagine that it is rare to have agreement on the differences, if any in such situations. Different listeners can have different opinions and all be right at the same time.

A corollary from this is, that is we miss the one attribute where two selections differ, we don't hear the difference, while in another session someone else (or even you) suddenly DOES hear a difference. Part of the advantage of trained listeners is that they (hopefully) are aware of these issues and can methodologically and mentally check each issue off.

All of this is assuming of course that there actually IS an audible difference, which is another kettle of fish...

Jan Didden
Click to expand...

I agree that A-B comparisons are necessary and that the mind can only consciously focus on one thing at time. But, we respond much more strongly (positively or negatively) to sounds that we are familiar with. And we use all information from our senses to process sound.

You can hide the components and learn only the sounds, for say a month. Then test yourself and listen for the differences you've learned or think you've learned. If you can identify them (blind) then the differences are audible. If you can't then there's likely no difference. You could even compare 5 or 6 different components at a time. Wouldn't make a difference.

Something I'll have to try sometime. Charles Hansen did essentially the same test, as he explained somewhere in this thread. Anyway, I have some cables in mind and am interested in testing this idea and see what I can hear, using my ears.

And people probably will not agree on what sounds better. It's still a subjective test. Intrinsic fidelity testing could help with that.
 
#18,865
Steve Dunlap said:
First, let me state that I am not saying blind testing is invalid. I have however participated in blind tests with unexpected results. These were not listening tests, but show just how easily people (including me) can be fooled.

The first blind test of this type came about when a master chef I was taking classes from flatly stated that no one in the class could tell the difference between Coke and Sprite while blindfolded. Of course we jumped at the chance to prove him wrong. The results were 50/50, the same as guessing.

The second test of this type was even more bizarre. We were to tell the difference in 5 different liquors. The 5 were vodka, gin, tequila, bourbon and rum. They were placed in our hand in shot glasses, randomly. All we had to do was identify each one. Only one person out of 14 got 3 correct. She didn't taste them, just smell.

I don't believe for a second that I can't tell these differences when I know what I am tasting. Why were the results so poor in a blind test?
Click to expand...


<Spock> "...fascinating Captain..."

But on the Coke vs. Sprite - both have Citric Acid, although Coke has phosphoric too, but both are dominated by the High Fructose Corn syrup carp that is in it, and both probably share some of the same "natural & artificial flavors"... so could be a dicey differentiation... I think it would have been much less difficult if it was 1960s Coke vs. 7Up - easier because it was sugar base and different "natural & artifical flavors".

As far as the liquor - hard to imagine that one could mistake Bourbon for something else... Vodka, Gin, Tequila and Rum sure... somewhat subtle differences.

Now, here's an issue, if most of these people use a common mouthwash (or if you do) on a daily basis, you have likely desensitized the tastebuds in your mouth. My dentist advised me to use the common mouthwash to help my gums, but I can report with confidence that it has strongly desensitized my tastebuds to the point that I can heat rather "hot" or "spicy" food now that I could formerly not tolerate before the moutwash. So, I guess if you want to be a chef you have two distinct problems and related audiences - those who have used mouthwash regularly and those who have not. The food you cook and provide would be quite different for each group.

Wonder how that relates to audio? 🙄

_-_-bear
 
#18,866
bear said:
If you happen to have a DAC or preamp that can swap absolute phase quickly (or just have a friend to swap speaker cable orientations) try the first cut on Mickey Hart's Planet Drum CD?
Click to expand...

Interesting, I will look for that CD. I've used the Sheffield drum disc for the test years ago and could hear an obvious difference between 'right' and 'wrong' phase by swapping cable orientation. Think I must organise that EmmLabs CD Player again. 😉
 
#18,867
stinius said:
I guess is that as the source of the FM radio signals you will find a pretty normal CD player, so why would it sound better if it is modulated – demodulated?

Isn’t that strange?
Click to expand...

Perhaps the FM radio use better op-amps than the Sony SACD player. 😀

Must say that I have a Sony DVD player that I wil not use for a CD player at all, my old modified Marantz is a whole different story though, I would love to hear a 'snap, crackle and pop' that can do better.😀

(I'm running now!)😀
 
#18,868
Franklin, You seem like a nice enough fellow, posting with good intentions. However, you have failed to read through this thread and have apparently showed up rather late and in the process you have missed a great deal of pertinent information. To that end, I sugges that you read first, talk second. Also do a thorough search for other threads that are related to this one, including those on other products that John Curl has designed and have been made into commercial products. Then report back if you still are frustrated by the lack of a "buildable design" for DIYers... Ok? _-_-bear
Click to expand...

Bear, I get the message and maybe you are taking your "task" as JC's communication channel too seriously. I just expressed my opinion just as others do. The concern I expressed was not because I personally need a buildable design. However it does seem a waste of time, but hey, don't worry because I won't interfere any longer. After all this is the gentlemen's academic design thread, were mortals like me are only creating noise. And if I want your advice on what to do, I'll ask for it, but for now I'm fairly capable of making my own decisions.
 
#18,873
courage said:


Bear, I get the message and maybe you are taking your "task" as JC's communication channel too seriously. I just expressed my opinion just as others do. The concern I expressed was not because I personally need a buildable design. However it does seem a waste of time, but hey, don't worry because I won't interfere any longer. After all this is the gentlemen's academic design thread, were mortals like me are only creating noise. And if I want your advice on what to do, I'll ask for it, but for now I'm fairly capable of making my own decisions.
Click to expand...

Sure, you can make your own decisions.
Did you search for buildable designs based on Curl's products??
No? Yes?

Noise is relative, relative to what you say. You complained. Why did you complain? I don't know. The problem is that what you said wasn't noise due to a lack of technical or engineering expertise, eh?

If you had read this thread, I think you would have learned a great deal about a wide range of topics. I have. That is why this thread is valuable, and widely read. Be thankful for this thread, it reads like the design course that is not offered at any University I know of...

I do not speak for John Curl, and to this point despite his noises to the contrary he has not sought my advice on any matters including this one.


stinius said:


Franklin
You are of course welcome to post. If Bear or anybody else is trying to sort out people, I think they have a problem. This is an open forum.

Cheers
Stinius
Click to expand...

Sure anyone can post - but why come in late and then complain?
And do so a few times?

Quote: "However it does seem a waste of time"

Ask a cogent question or bring something meaningful to the discussion??

_-_-bear
 
#18,875
bear said:



Franklin,

You seem like a nice enough fellow, posting with good intentions. However, you have failed to read through this thread and have apparently showed up rather late and in the process you have missed a great deal of pertinent information.

To that end, I sugges that you read first, talk second. Also do a thorough search for other threads that are related to this one, including those on other products that John Curl has designed and have been made into commercial products.

Then report back if you still are frustrated by the lack of a "buildable design" for DIYers... Ok?

_-_-bear
Click to expand...

Sure Franklin has "failed" to read the entire 755 pages, and so has just about anybody else.

Considering the fact that this thread is 90% ego-exercise, who can blame him.


Magura 🙂
 
#18,879
gerhard said:


Hi, Stinius,
you forgot to mention the compressor that leaves a dynamic range of 6 dB,
plus another 3 dB step used to make advertisements louder.

;-), Gerhard
Click to expand...

Gerhard

Good point, but anyway JC will never answer my first question so the conclusion seems to be that if you take a lousy signal, compress it, modulates it, use a class C amp and an antenna to transmit the signal to another antenna demodulate the signal and it “sounds” better then a SACD.

Strange, isn’t it?

Cheers
 
Status
Not open for further replies.
Top Bottom