AB..X?? box

[AJ Soundfield]

http://www.dagogo.com/audio-by-van-alstine-abx-comparator-review-part-1-audio-store-wiring

I'm going to have to read a bit more to figure out where X factors in.

 

[Speedskater]

The original AB/X test & box.

http://djcarlst.provide.net/abx.htm

 

[AJ Soundfield]

Yes aware of that one and the QSC.
The question pertains to the VA one.

 

[amirm]

I had seen this a while back and was going to buy it. It was either expensive or not available. Don't recall now.

I read through his first test. It doesn't make sense to me. He compares two complete system with two different speakers! Of course one can pass ABX with two different sounding speakers.

 

[AJ Soundfield]

I had seen this a while back and was going to buy it. It was either expensive or not available. Don't recall now.

I read through his first test. What a colossal fail. He compares two complete system with two different speakers! Of course one can pass ABX with two different sounding speakers.

It seems that some of the simplest principles here are not understood by the reviewer.

Help me out Amir.

Where is X on this ABX box?

 

[amirm]

Help me out Amir.

Where is X on this ABX box?

From my quick read of their manual, it is a forced AX tester. X can be A or B. You can accomplish the same thing as ABX.

 

[SoundAndMotion]

From my quick read of their manual, it is a forced AX tester. X can be A or B. You can accomplish the same thing as ABX.

I don't get this thread. Is there a joke I'm missing? Perhaps it's a critique of the review, not the box...
The original link is a review. The manual is here. On pages 6-9, the formal test procedure is described. There is a limit of 8 randomized X's, so for more trials you'd have to repeat the randomization. It may be clunky but according to my quick read, it is true ABX, not forced AX.

 

[amirm]

In an ABX test, you have A, B and X which you can select at will. This box only has A and B. That is what AJ is observing and asking about. The only way it can perform anything like ABX is to have A be A, and B being X. X will either be "A" or "B." This is forced AX testing.

Is your read different?

 

[SoundAndMotion]

In an ABX test, you have A, B and X which you can select at will. This box only has A and B. That is what AJ is observing and asking about. The only way it can perform anything like ABX is to have A be A, and B being X. X will either be "A" or "B." This is forced AX testing.

Is your read different?

Yes, my read is different (but that doesn't mean it's right!!) It is very clunky, using non-intuitive buttons on the remote. But once you have set up the 2 systems: A (ENTER) and B (INPUT), you can listen to either by pressing "ENTER" or "INPUT" whenever you want.
When you want X, you enter the "Blind Test Mode" by hitting "ON-OFF" followed by "1". Then 8 "Tests" are created with A or B being randomly chosen for each "Test".
You write down your selection for each test ("Test 1" through "Test 8"), write "A" or "B"
When you're done you can turn on the answer with the "MUTE" button.
Anytime during the test, you can hear "A" or "B" again by hitting the "ENTER" or "INPUT" buttons. To return to the last test you were doing, which is still unknown to you, hit "0".
I think it is very non-user-friendly, but it should work this way, with my reading.

Let know know if you understand it differently. Either click here... or read it below:

Blind test mode activation

Once two systems have been defined with the “ENTER” and “INPUT” switches, and the volume of the two systems is closely matched, you are ready for blind test mode.

It is important to realize that volume has a tremendous effect on how the brain perceives audio. A system that is slightly louder than another system has a tremendous advantage in being selected as the better sounding system. Take care in matching levels. A sound pressure meter and a white noise generator, used at moderate levels, are recommended for this purpose. However, careful level matching by ear will probably work well for you.

Press “ON-OFF” followed by “1” to enter the blind test mode. The LED’s will go out, the relays will click, and a “1” will be displayed (to indicate test 1), and “blind test” will be displayed.

A random number is “grabbed” when ON-OFF followed by “1” button is pressed to enter blind test mode. That random number is used internally to select either system “ENTER” or system “INPUT” for the 8 tests that are used in the blind test mode. You won’t know the starting system at this time.

The VOL UP/DOWN or CHAN UP/DOWN buttons will either advance or retard the test number. Wrap occurs, so TEST 8 plus VOL UP will go to TEST 1, TEST 8 plus VOL DOWN to test 7.

At each test step, the ABX Comparator either changes to the opposite system, or not, depending upon what it feels like doing to mess with your mind.

You can listen to each test step for as long as you desire. Make detailed notes of course, labeling your written observations identified with each test step. Once the 8 tests have been listened to and you decide what you like best (or don’t like) you can reveal which system goes with which test.

To reveal what you were listening to above, press the “MUTE” button to toggle the LED’s back on. You can now step through the tests again, using the VOL UP/DOWN button, and see which system was selected for each test. It should be noted that there is a 1 in 256 chance that all 8 tests will select the ENTER system so no changes will occur throughout the entire test. Likewise there is a 1 in 256 chance that all 8 tests will select the INPUT system.

At any time during blind test the MUTE button will toggle LED’s on/off, you need not wait until the end of the test to reveal what you are listening to. Similarly, at any time during the test, you may press ENTER to change to the ENTER system (A), press INPUT to change to the INPUT system (B), or press “0” to return to the current random test (X). “A” or “B” are displayed in place of the random test number when this occurs
To exit and end this blind test after you have evaluated your results press ON-OFF followed by “0” or simply press the STOP button.

 

[AJ Soundfield]

Anytime during the test, you can hear "A" or "B" again by hitting the "ENTER" or "INPUT" buttons. To return to the last test you were doing, which is still unknown to you, hit "0".
I think it is very non-user-friendly, but it should work this way, with my reading.

Similarly, at any time during the test, you may press ENTER to change to the ENTER system (A), press INPUT to change to the INPUT system (B), or press “0” to return to the current random test (X). “A” or “B” are displayed in place of the random test number when this occurs

This is worded very poorly, but the only thing I see as an "ABX" comparison. "May?"
They make it sound like an "option" during the "test". WTH?
Yes, I suppose here one would indeed be able to switch between A, B and (random) X. I'm not clear this is what DS did.
SAM, glad I flushed you out of hiding . Amir, perhaps invite Doug here? He seems to be one of the rare reviewers with >2 brain cells.

 

[krabapple]

Why is it that these maroons always have to invent new reasons for failing? Now it's 'orientation effect'. And it appears he is comparing two *systems*, including loudspeakers. Sheesh. *Audiophiles*, God's peace be with them.

 

[Blumlein 88]

Why is it that these maroons always have to invent new reasons for failing? Now it's 'orientation effect'. And it appears he is comparing two *systems*, including loudspeakers. Sheesh. *Audiophiles*, God's peace be with them.

I posted some recorded files on another site. Two were identical originals and one was through an 8th generation AD/DA loop. I chopped 107 samples off of one of the originals. To keep people from simply looking at file size to see which two were originals and cheating so to speak. Well, once that was known the audiophiles report all three sound different. Quite a bit of back and forth on how a different beginning order of samples trickles through digital filters and alters significantly the sound of both otherwise bit identical files. So much so the chopped file and the 8th gen file sounded similar though different and the unchopped file was very different. Hard to believe this they believe, but there it is.

 

[AJ Soundfield]

Why is it that these maroons always have to invent new reasons for failing? Now it's 'orientation effect'. And it appears he is comparing two *systems*, including loudspeakers. Sheesh. *Audiophiles*, God's peace be with them.

C'mon now, he's a good guy. I think he fumbled a bit but jeez he's actually testing. I still don't think "ABX", but even AB or AX is better than freaking daydreams