John Curl's Blowtorch preamplifier part III

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Thanks vac, I did notice my listening ‘sweet spot’ is reduced dramatically and speaker placement was also more critical.

I Remember the Polk setup where the left and right signals are swapped on each side,between the two tweets (two tweets per baffle,left signal,to one tweet right to the other)
Does anyone know how to wire that?
 
My logic is commutative and invertible.

IMO, as the list of premises that must be true is only implicit given and you could be talking just about a theoretical framework that might be possible in the future, it is a bit hard to say.

In case that you were talking about the situation now and in the past, it gets difficult; which way would like to show that any listening test was _really_ 'ears only'?

Further which way could one show that the 'organs picking up .....' were not able to detect a (maybe existent) difference?

And which way could you show that a difference did 'automagically disappear' , as all you know are a set of number from which you conclude something in dependence of the current model that you're using?

In a typical controlled listening test the experimenter finally does not know anything about the internal states of mind or what the 'organs' picked up or did not pick up.
In the context of the previous discussion about using the term 'ears only' I still think it is an illustrating example for the problems arising when using such descriptors.

Based on hundreds of discussions in audio forums about these topics and in the real world, I think it is a valid hypothesis to assert that misunderstandings are most likely. :)
 
... There is no reason to measure distortion at the listening position. As to anechoic rooms, silence is your friend with these kinds of measurements. Fortunately, there are a couple of anechoic rooms for hire in the Netherlands...
Unlike those with supernatural ability, I can not perceive music directly from electrical signal and can only enjoy music as soundwave from my listening position. Eduardo de Lima showed less total distortion from a 0.8% distortion single ended amp compared to the so called low distortion amp tested on a single driver. I find our understanding of distortion and high fidelity rather incomplete without measurement relevant to what most people are able to experience.
 
Hi Chris,

My bro is on prescript oxy and cannibas for sever diabetes pain in his legs, he had to sign a contract with the Dr. and is required to provide regular urine samples, as requested, to prove that he is taking the meds. I was informed the street drug addics want the "TEC" marked pills, percocet, so they can gind n snort them. percocet are oxy and acetaminophen.
Mum fell yesterday night, we gave her half a Oxy, it relieved her pain a bit better than the T3, which are no good but that is all they will give her, the T3's bind her up because of the acetaminophen. I am trying to get Mom to take tinctures but because it ain't from the pharm she is reluctant, work n progress :)

If solder composition or pcb materials make a difference in sound reproduction, then submit your papers to the AES and let the experts have a go at you, not a bunch of arm chair quarterbacks.
 
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So it would be a beaming dependent THD test?

Because the beaming prevents acoustic short circuiting of the harmonics, it may give you a rough idea. Obviously only works to the extent that the fundamental gets effectively suppressed.

Indra, I am not saying that loudspeaker distortion measurements are irrelevant, because they are. However, to measure them at the listening position is not relevant because there are better locations to measure this. For frequency response of course this is different if you want to eq out the room.
 
....So you can't make assumptions about what a class of drug does to people. You have to ask to find this out. I hope my experience helps to shed some light on a very poorly reported subject.
-Chris
Thanks for the refresher on your situation, it is all good information and well wishes always.
I have spoken to other people and gotten different views and experiences of antidepressants and all are different of course, it seems intelligence level is helpful in positive outcome.
 
@vacuphile
Off course there are still issues, some measurement procedure, interpretation or technique may need to be developed or reevaluated. Measurement at other location may leave out some important factor.

The fact remains that there is still a very strong but only partially correct view that best fidelity needs the lowest distortion present as signal at the output of the power amplifier. And most designers are ignorant, dismissive, uninterested or find themselves helpless about distortion generated from that point on.
 
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Hi Rick,
Yes, the contract is normal, and you also have to forgo any other drugs that the treating physician doesn't know about or has not approved. Peeing in the cup is normal too, and on a surprise basis. There is no fooling around with this stuff.

I use Endocet, which is almost the same as a Percocet. Yes, it binds you up pretty badly. In my case it is for "breakthrough pain" and I typically need two of those per day. They allow me to take the dog out for a walk. I take one 1/2 hour to an hour before I go out. If not, I end up on the floor in pretty severe discomfort.

Hi Dan,
No worries.

I think too, that it helps when they have you on the correct medication. I wouldn't be surprised to see that a significant percentage of people are on the wrong drug. That would confound your data big time. Then there are those who don't need the drugs, but they like playing the "injured" part. I would say that a solid 70% of people in my WSIB classes were not injured, but there were a couple people a lot worse off than I am. Those people need to see the inside of a jail for fraud.

-Chris
 
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