Sir, if you would care to look into psycho-acoustics in particular and perception in general, you would be aware that what you perceive to hear is unreliable in the extreme. That is the basis for the scepticism some of us have.
Can we now go back to regular programming? Where are we on acquiring those two QP's? Who's doing that?
SY, you already got a structure for the tests you want to run?
jan didden
Cal has arranged for them to be winging my way.
I'll start with trying to get the same sort of noise reduction that JC showed on ripple waveforms, then move on to noise and distortion as discussed with Scott and Joachim. We'll see what those show, then throw open the discussion to "next steps."
exeric. You are just trolling now. That is against the rules. The object of this thread is to test a pair of Bybee purifiers. The first tests will be electrical, so see if there is any measurable difference found and if the difference is not what a simple resistor of ferrite bead would give.
After those tests are made, listening tests will surely be done. They will be controlled tests. Please limit your remarks to the scope of this thread. This goes for all others posting here.
OT posts removed.
The object of this thread is to test a pair of Bybee purifiers. The first tests will be electrical, so see if there is any measurable difference found and if the difference is not what a simple resistor of ferrite bead would give.
After those tests are made, listening tests will surely be done. They will be controlled tests. Please limit your remarks to the scope of this thread. This goes for all others posting here.
OT posts removed.
Moderator,
I understand your concern. However my remark about judge, jury, and executioner are well founded. Even in the most technically pristine testing environment group think and pre-determined biases creep in. This is well documented throughout the scientific literature. Subtle cues can be injected that condition a person to perceive a certain thing. It is similar to leading a witness to answer something that that he thinks the questioner will approve of. This would apply to listening tests, which I think is the most valid form of testing for the Bybees.
I think it is important to do the tests in a double blind way by unbiased listeners. But it has to be administered by someone who is equally unbiased. I think this makes sense. I would not ask to be the one who is in charge of this because I have previous experience which has formed an opinion in me about the Bybees. Similarly others who have formed a strong opinion should also not be in charge of this part of the testing. I am not asking for anything here but fairness in getting unbiased results.
No, it was not. John gave no information whatever on how the plots were obtained, the test setup, or anything which would allow direct replication. I'll do guessing and trial-and-error, but whatever I get, the test conditions and procedure will be fully disclosed.
Guys, at this moment I am sitting in the middle (OK by a window) of a million dollar RF lab. RF design engineering is what I do for a living. Most of my work covers 100 MHz to 1GHz but I have equipment covering DC to 6 GHz. If you have any specific tests in mind, or just want them run on a network analyzer and compared to say a wire, a wire with one or more ferrite beads, and a resistor let me know.
Yes, I am a skeptic, but as an engineer I have an open mind. It was explained to me in another thread that I couldn't measure or hear the difference between a $2 power cord and a $200 power cord because my equipment wasn't revealing enough. OK, I'll accept that. And I will accept my non revealing system complete with the power cord off of an old computer AND the speaker wire from Walmart too. Of course if the QP's wind up here for testing they might find their way into my system, but I wouldn't expect my non revealing system to reveal anything earth shattering.
If the tests are double blind, you can be as biased as you want, that's the whole POINT of controlled testing. You either hear a difference or you don't, irrespective of your preconceptions.
Man up and do it. Or come to our October 21 geekfest/concert where we'll have a pair and I'll let you DBT to your heart's content.
George, I'll be happy to send them along for RF testing as soon as I'm done in the audio and ultrasonic band.
Hi SY,
I was just about to mention that I also have an audio frequency network analyzer now. It's good to 51 KHz or so. My spectrum analyzer creaks up to 40 MHz.
George, you're a lucky devil! I really want to see what you come up with there. BTW, a million dollars is relatively easy to spend on good RF gear. At this price point, there isn't much you can't detect because your equipment certainly is revealing enough. Your skeptic doesn't know what they are talking about at all.
-Chris
I was just about to mention that I also have an audio frequency network analyzer now. It's good to 51 KHz or so. My spectrum analyzer creaks up to 40 MHz.
George, you're a lucky devil! I really want to see what you come up with there. BTW, a million dollars is relatively easy to spend on good RF gear. At this price point, there isn't much you can't detect because your equipment certainly is revealing enough. Your skeptic doesn't know what they are talking about at all.
-Chris
Good. As far doing the double blind testing myself, I have neither the time or energy to do it. I should say this: it requires great familiarity with a piece of equipment to be able to notice subtle changes for worse or better. I hope you are not planning on doing the test at the Geekfest. I think the listening test should be done on very good unmodified equipment that observers have had several days preferably weeks to familiarize themselves with on different varieties of music. One's mind and ear has to narrow in on the positives and negatives of a system beforehand. This takes time. Only then should the double blind listening test occur, presumably on equipment in which one of the two presented identical systems has had the QP installed. If there is a difference it should be noticable. Equally important is the listeners overall conclusion of which of the otherwise identical systems he prefers listening to.
Actually now that I think about it a modification should be to this test procedure. An equal number, but different listening group, should get their several day familiarization on an identical but modified system. When the actual double blind test occurs some will notice that one system sounds slightly worse than they remembered it. The other group will find that one system sounds slightlly better than they remember it. That is provided they hear a difference.
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I can't believe this is actually happening, it's just too good to be true. And I have a couple of (weird?) questions:
How will the devices be placed in the signal path? Screw terminals? Solder? How much heat can they take? Stuff like that is usually covered by a datasheet...
I suppose at some point there has to be RCA/BNC/SMA/whatever connector to connect to the equipment, so...how will this connection be made? I'm just curious because it probably should be reversible. How do solder joints behave at high frequencies? Maybe also test a wire with two solderjoints then...
And isn't it unusual for RF labs to have windows?
How will the devices be placed in the signal path? Screw terminals? Solder? How much heat can they take? Stuff like that is usually covered by a datasheet...
I suppose at some point there has to be RCA/BNC/SMA/whatever connector to connect to the equipment, so...how will this connection be made? I'm just curious because it probably should be reversible. How do solder joints behave at high frequencies? Maybe also test a wire with two solderjoints then...
And isn't it unusual for RF labs to have windows?
I believe that my Altec 288 drivers on 1005 horns should be revealing enough for a test like this. If you can't hear it there, it's going to be hard to hear it anywhere. And I know the system very well.
Unfortunately I do not know how to set up a good double blind test. Any help there would be welcome. I have no expectations of the outcome.
Good questions about the connections, I was wondering the same myself. I saw nothing on the Bybee website about this.
Unfortunately I do not know how to set up a good double blind test. Any help there would be welcome. I have no expectations of the outcome.
Good questions about the connections, I was wondering the same myself. I saw nothing on the Bybee website about this.
Any good connection used in RF work will be fine. That includes soldered connections using a lead based solder (for high rel). Heck, stick one end in a waveguide and use it's terminal as the antenna. How's that for direct?
George can determine differences in wire dimensions fairly easily. He can also excite the Bybee to find it's self resonant frequency in the event that SY's gear doesn't reach those frequencies. A creative mind with the right test equipment can learn the secrets (if any) for any "black box". After all, the Bybee is a black box device.
-Chris
George can determine differences in wire dimensions fairly easily. He can also excite the Bybee to find it's self resonant frequency in the event that SY's gear doesn't reach those frequencies. A creative mind with the right test equipment can learn the secrets (if any) for any "black box". After all, the Bybee is a black box device.
-Chris
By reading those lines ''Once in a life time there comes along a technology that breaks new ground and is easily worth its weight in gold. Such is the case with the Bybee Quantum Purifier.'' & ''if there ever was a no-brainer recommendation, the Bybee Quantum Purifier is it. I can't imagine listening to my system without them.'' from D. Olser's review, I would suppose it will be clear to pick it up. He is just talking about putting those in line with a Lowther DX4 and then with its helper woofer. Nothing too exotic.
Frankly I don't really care so much how the QP's sound. This thread is awesome because here it's about measurement (taking data) and analysis (interpreting data). The data will express how the device performs in terms of well established units of measurement, like Volts, Amperes and Herz. If calibrated equipment is used to derive these characteristics, then we'll know what the device does within certain boundaries (aka error). Repeatable, anytime, anywhere. That's why people have established these standards of measurement. Listening (unfortunately) is not one of them.
If these devices do something it must/will show. If there's one thing I've learned it's that the atoms don't lie.
If these devices do something it must/will show. If there's one thing I've learned it's that the atoms don't lie.
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