Can someone recommend specific source components that are best with a Blowtorch?
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I don't think anyone (other than JC) can build the Blowtorch, since AFAIK there is no published schematic of it. Also, some parts are obsolete and difficult to get.
[snip]so, you do not trust the testees
You don't want to rely on trust in a scientific endeavour.
You don't want to end up with a positive result and then someone on the other side accuses you of measuring it secretly and thus scoring well. People are people 😉
jd
Everyone, for me it is just to listen and try not to be caught up in obvious bias. That means that I don't brag about what others have not heard themselves. However, I happen to believe that much is audible that is difficult, if not presently possible, to measure. It is not that I don't like to measure, but even when I do, I get shouted down by the same people here, who don't like my listening opinions, and told that I am screwing up my measurements. Then, of course, Dr. Hawksford is taken to task for his measurements, and Otala is criticized, and then Jack Bybee is called a liar and a fraud. And so it goes. Well, none of this gives me ANY more insight, so I chose to politely (if possible) ignore them.
What I do, is design audio products, and I will continue to do so, with every trick and insight that I can find. If you don't think that I am on the right track, please find someone else to advise.
What I do, is design audio products, and I will continue to do so, with every trick and insight that I can find. If you don't think that I am on the right track, please find someone else to advise.
Just for fun, I would like to talk about my first audiophile 'tweak'. It was late 1963 or early 1964 and someone loaned me an Audiophile magazine, where Ed Vilcher (sp) stated that the AR-1 loudspeaker, the very speaker I then owned, worked best with a damping factor of 1.
However, my Dyna Mk 3 had a damping factor of 15. What to do? Well, I found this 20W or so Dale power resistor with 3.2 ohms or so resistance. I then put it in series with the AR-1, AND it really sounded better. Now, at the time having 3 years of college in engineering-physics and a year as a technician, I knew that I was losing a lot of power across that resistor. Yet, it still sounded less 'under water' with the resistor installed. I kept it in the circuit.
However, my Dyna Mk 3 had a damping factor of 15. What to do? Well, I found this 20W or so Dale power resistor with 3.2 ohms or so resistance. I then put it in series with the AR-1, AND it really sounded better. Now, at the time having 3 years of college in engineering-physics and a year as a technician, I knew that I was losing a lot of power across that resistor. Yet, it still sounded less 'under water' with the resistor installed. I kept it in the circuit.
iir, matching source impedance to load impedance (df ~= 1) helps to minimizes reflections in transmission lines
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(sorry, for the confusion pma and joshua_g; i wasn't asking about components inside of the blowtorch)
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(sorry, for the confusion pma and joshua_g; i wasn't asking about components inside of the blowtorch)
- for the record, johnferrier, I did not state any preference for a recording medium (such as "tape").
_-_-bear
_-_-bear
Just for fun, I would like to talk about my first audiophile 'tweak'. It was late 1963 or early 1964 and someone loaned me an Audiophile magazine, where Ed Vilcher (sp) stated that the AR-1 loudspeaker, the very speaker I then owned, worked best with a damping factor of 1.
However, my Dyna Mk 3 had a damping factor of 15. What to do? Well, I found this 20W or so Dale power resistor with 3.2 ohms or so resistance. I then put it in series with the AR-1, AND it really sounded better. Now, at the time having 3 years of college in engineering-physics and a year as a technician, I knew that I was losing a lot of power across that resistor. Yet, it still sounded less 'under water' with the resistor installed. I kept it in the circuit.
Did you do a blind test against your unmodified speaker?
No, I just did a simple A-B with a friend of mine, someone who was also into hi fi. He convinced me that the resistor made a positive difference, just like I heard.
The idea to do a ´competent´ 🙂 test in a way, that the participants would not realize that they are part of a double blind test was appealing and as said before i tried that once with two preamplifiers.
Two identical looking cases with labeling changed in random order between the participants and used for a preference test. One of the screws was invisibly sealed, but as the looks inside were extremely similar it would probably not help to establish a preference for one of the units to look at it.
Measurements for both units was (of course) different, but well below any established hearing threshold between DC - 50kHz.
Every participant got the units for a couple of days and should tell afterwards which one (if one) he would prefer for listening.
Due to the ´hiding of the test´ it was not possible to ask the participants for a run of trials therefore the main problem was to find a group with consistent preference.
We were only able to find five listeners, who would in my opinion prefer the same preamplifier as i did, if they were detecting a audible difference.
I did not know which label belonged to which version during the handing over the units to the listeners.
Over two months we collected the results and after revealing the random labeling order it occured that all had choosen the same unit.
@ SY,
it does in no way help, that similar test did work for other participants other tasks and so on, especially if you want to test a claim of a person that already expressed feeling distracted by test conditions in the past.
It should be obvious that a careful (means interested in the truth) experimenter has to address this point.
Two identical looking cases with labeling changed in random order between the participants and used for a preference test. One of the screws was invisibly sealed, but as the looks inside were extremely similar it would probably not help to establish a preference for one of the units to look at it.
Measurements for both units was (of course) different, but well below any established hearing threshold between DC - 50kHz.
Every participant got the units for a couple of days and should tell afterwards which one (if one) he would prefer for listening.
Due to the ´hiding of the test´ it was not possible to ask the participants for a run of trials therefore the main problem was to find a group with consistent preference.
We were only able to find five listeners, who would in my opinion prefer the same preamplifier as i did, if they were detecting a audible difference.
I did not know which label belonged to which version during the handing over the units to the listeners.
Over two months we collected the results and after revealing the random labeling order it occured that all had choosen the same unit.
@ SY,
it does in no way help, that similar test did work for other participants other tasks and so on, especially if you want to test a claim of a person that already expressed feeling distracted by test conditions in the past.
It should be obvious that a careful (means interested in the truth) experimenter has to address this point.
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[snip]
Over two months we collected the results and after revealing the random labeling order it occured that all had choosen the same unit.
Jakob,
That's an interesting report, well set up. I had at one time the idea to do something like that with two boxes, one having a very high quality coupling cap and the other a run-of-the-mill electrolytic coupling cap. I never got around to doing it though.
Is there a measurable difference that you are aware of that could explain the preference difference?
jd
J I had at one time the idea to do something like that with two boxes, one having a very high quality coupling cap and the other a run-of-the-mill electrolytic coupling cap. I never got around to doing it though.
Here's another way to do it. The box goes between preamp (or source) and electronic crossover. Switch is a Cinema Engineering massive silver contact job, caps are a V-Cap reference versus an NTE bipolar electrolytic, 1uF. Wiring on the V-Cap side is all silver-Teflon, with silver solder; on the electrolytic side, it's cheap Radio Shack wire with 63/37. Switch Position 1 is Fancy, Position 2 is Cheesy, Positions 3-17 are randomized. Grounds are switched as well, and both caps have bleeder resistors on each side to prevent pops.
When you're here in October, I'll hand you the box and you can have fun telling me which position is which. 😀
Attachments
I'm looking forward to it! I can already feel the test anxiety.
But did you really have to sacrifice a beautiful HP precision 600 ohms attenuator to chase these ghosts 😉?
jd
But did you really have to sacrifice a beautiful HP precision 600 ohms attenuator to chase these ghosts 😉?
jd
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Beautiful it was not!
I did salvage the actual attenuator switches, but they're sealed and set up for 600 ohms, not exactly useful in this day and age.
I did salvage the actual attenuator switches, but they're sealed and set up for 600 ohms, not exactly useful in this day and age.
Beautiful it was not!
I did salvage the actual attenuator switches, but they're sealed and set up for 600 ohms, not exactly useful in this day and age.
I know, I have one of those exact same boxes.
jd
Sorry for OT....
I don't trust that box. Some of the good audio may leak from the open hole on the right.
John
John
I don't trust that box. Some of the good audio may leak from the open hole on the right.
John
No, the hole is sized and positioned specifically to allow the internal Maxwell Demon to control the spin of each electron passing through. The quantum alignment enhances the timbral purity, intertransient silence, microdynamics, and inner detail. Anyone who isn't deaf and thoroughly insensitive can hear the difference.
No, the hole is sized and positioned specifically to allow the internal Maxwell Demon to control the spin of each electron passing through. The quantum alignment enhances the timbral purity, intertransient silence, microdynamics, and inner detail. Anyone who isn't deaf and thoroughly insensitive can hear the difference.
Sy
I reserve the right to quote you on this verbatim, but out of context at the most inappropriate time!
ES
Sy
I reserve the right to quote you on this verbatim, but out of context at the most inappropriate time!
You always have my permission to make me look like an idiot. 😀
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