As usual you have to be more specific, do you mean DC or at some higher frequency and what do you mean by PSRR. If you mean I change the power supply by 1V and get less than 1mV referred to input error yes every day in fact -120dB is easy. BTW the PSRR of a power supply is a nonsense, unless you are talking power supply output vs mains voltage. LIGO managed -180dB.
Jeez we're off to the races again.
The buss structure at LIGO
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Need to check out that thread then!
Well, I was aware that these "quantum" thingys exist. But somehow I expected them to be seen in much the same way by audio people as the Amish are seen by mainstream Americans. But to see them defended by an engineer like Curl... really bizarre.
Well, I was aware that these "quantum" thingys exist. But somehow I expected them to be seen in much the same way by audio people as the Amish are seen by mainstream Americans. But to see them defended by an engineer like Curl... really bizarre.
In order to have a valid opinion, you really would have to try one first. Now it's perfectly understandable that you don't want to spend the money for a test like this and that's okay. But calling those who use Bybees Amish, bizzarros, and snake oil salesman is not okay. Why the insults?
If you're curious, maybe someone on this forum is willing to send you one to try for just the shipping cost.
And if you don't hear a difference, or it makes things worse and you're honest about it, you should be able to post your opinion freely.
So you also agree Tryphon the blind, ears only no instruments test is the final arbiter?
Not sure about the others but Thorsten and others presented all this here 15 years ago.
Current Driven Loudspeakers and Tranconductance Amplifiers
"
My point is that Speakers of the conventional sort are current conrolled devices. This means if you feed the speaker with a voltage, meaning from a low impedance source (theoretically a zero impedance source), then the current flowing through the Speakers voicecoil will be a result of the voltage applied and the drivers impedance. Here comes the trickey part. The Drivers impedance (even if we discount mechanical resonances) is highly non-linear and signal dependent.
"
Current Driven Loudspeakers and Tranconductance Amplifiers
"PS, driving moving coil speakers designed to require external electrical damping will not work of course, we must in effect design drivers with a Qm in the region of 0.3 to 1 as the only possible damping is mechanical.
A good choice would be a seamless Aluminum coil former, this would both kill some of the eddy current problems in the polepieces and reduce the drivers voicecoil inductance drastically and it would give inherent damping to the driver that would in effect appear as very low Qm. Of course, such a speaker when driven from a normal amp would have absolutely no bass..."
"
Given that Speaker has a voicecoil that is filled with a solid iron plug (causing eddy currents to be induced) and given that the voice coil gets hot and is wound with copper or aluminum (instead of constantan) and thus increases it's resistance it should be PAINFULLY obvious that driving a moving coil speaker from a modulated voltage source (Amplifier with low output impedance) will MAXIMISE the system wide distortion and will cause significant levels of short and long term compression.
"
http://www.diyaudio.com/forums/mult...rs-tranconductance-amplifiers.html#post127252
http://www.diyaudio.com/forums/mult...-tranconductance-amplifiers-2.html#post128071
http://www.diyaudio.com/forums/mult...-tranconductance-amplifiers-3.html#post128627
"
So, if we actually take the Horse and put it before the cart (instead of the other way around), we find that the linear variable controling the force on the drivers cone is the current, so a current output amplifier is used.
Secondly, we find now that we need to account for a suddenly sky-high Drive unit Qt. We find this of course easy to do, as all we need to do is to make the resonant system less effective, by using a leaky box, acoustic labyrinth etc. We do not need to boost bass by adding rsonance (Horn, Transmission line or Reflex).
So, suddenly we have freedom from compression, low distortion in certain areas and with a suitably adjusted enclosure even low frequency response reaching down to the build in resonance of the driver.
"
http://www.diyaudio.com/forums/mult...-tranconductance-amplifiers-4.html#post452408
"On the contrary, if you had read Nelsons paper you would realise that the EXPLICIT aim is to provide a system with a near critical damping. No, the aim is not a Q=0.7 System most of the time, as many people perfer (as also Nelson remarked and was observed by Jecklin and others) a Q around 1 - 1.2 (for whatever reasons).
My original point was that by using the right measures (of which I know of around 4 or 5 and can imagine several more) you can by making the Amplifier, Driver and Enclosure (or lack thereoff - Dipole) a "tuned system" achieve any sensible desired LF response efficiently and with good transient response."
http://www.diyaudio.com/forums/mult...-tranconductance-amplifiers-4.html#post452408
Nelson, phase_accurate, Steve Eddy, etc ... all get into the discussion
... and that was 15 years ago?!?
Where are the results, where is the data? Where is the advancement?
Cheers,
Jeff
I usually don't say things like this. Honestly. Life is too short, and I prefer to engage constructively on the big things in audio that matter a great deal (speakers and rooms and DSP solutions), not quarrel on the small things that at best help on the margins. But I perceived the Bybee products as being so far out - way beyond the usual audiophilia mystica - that I just wasn't able to hold back. My apologies if anybody was hurt. Now back to discussing things that really matter.
Where every technique that requires a deviation from the norm goes, to the fringe. Just like current mode phono interfaces, they are marginalized to the few that can DIY. A super duper preamp that simply requires you to find a tech to lift the ground on your TT is for most folks a nonstarter.
I wouldn't apologize. They are clearly snake oil or the product of delusions. You want to take the moral high ground here because you're a reasonable person, but I think it's important not to give in to those who attempt to legitimize this sort of quackery. It's like dealing with anti-vaxxers.
I can only see the QF25 flanges coming off the rotary vane pump in the background. Not sure what that says about me! 😉
Hi John,
Just recently in years you did say that the Bybee was a military secret that could not be revealed. If you can't remember what you said before, write it down!
Listen, I know you get your kicks from stirring the pot and winding up poor lost souls like ridikas here (poor fella, wait 'till he finds out the truth!). Then you watch them spin out of control visiting the bin and such. It's all great fun to you.
I'm only keeping you honest John. There is zero fear here and I don't persecute you or anyone else. I just don't like the smell of dung, horse or otherwise. While I'm at it, let's be honest. You are not an engineer. You studied Physics. You have been doing the job of an engineer without the training. I also just realised, since you are not an engineer, you have no ring and have not taken the oath to represent your endeavors and / or advice honestly. Hmmm, I hope that isn't it.
Now, I know SY well and he is a personal friend. He honestly tested that Bybee device and then returned it to the member (a moderator) who actually paid for it with his own money. They did what was asked and reported honestly. Why is that report unacceptable to you? Just to let everyone else know, SY is a scientist and does set up experiments properly (I've watched him do this) and I trust his results completely. Had he said there was something there, I would have accepted that and would support Mr. Bybee. I have seen and hefted same. I don't believe they do anything other than what a low value resistor does. At least Bob Carver was honest when he brought out the TFM series of amplifiers with the resistor in series with the output.
Come clean John, some day ...
-Chris
Just recently in years you did say that the Bybee was a military secret that could not be revealed. If you can't remember what you said before, write it down!
Listen, I know you get your kicks from stirring the pot and winding up poor lost souls like ridikas here (poor fella, wait 'till he finds out the truth!). Then you watch them spin out of control visiting the bin and such. It's all great fun to you.
I'm only keeping you honest John. There is zero fear here and I don't persecute you or anyone else. I just don't like the smell of dung, horse or otherwise. While I'm at it, let's be honest. You are not an engineer. You studied Physics. You have been doing the job of an engineer without the training. I also just realised, since you are not an engineer, you have no ring and have not taken the oath to represent your endeavors and / or advice honestly. Hmmm, I hope that isn't it.
Now, I know SY well and he is a personal friend. He honestly tested that Bybee device and then returned it to the member (a moderator) who actually paid for it with his own money. They did what was asked and reported honestly. Why is that report unacceptable to you? Just to let everyone else know, SY is a scientist and does set up experiments properly (I've watched him do this) and I trust his results completely. Had he said there was something there, I would have accepted that and would support Mr. Bybee. I have seen and hefted same. I don't believe they do anything other than what a low value resistor does. At least Bob Carver was honest when he brought out the TFM series of amplifiers with the resistor in series with the output.
Come clean John, some day ...
-Chris
Good News Dept --
We are at the point now where we can accomplish some fantastic things for increased accurate sound.
From my first RTA concept published in 1977, I learned that you can really only EQ the direct field sound ... reverb time, room modes, reflection and peaks and nulls caused by the room will have to be addressed some other ways.
View attachment Poptronics-1977-09-OCR-Page-0041.pdf
View attachment Poptronics-1977-10-OCR-Page-0060.pdf
Now we can get close to doing this ---> compare the audio signal going into the PAmp with that at the mic/listening position and 'correct' it to be same as input signal via DSP and SW.
How cool is that?
THx-RNMarsh
We are at the point now where we can accomplish some fantastic things for increased accurate sound.
From my first RTA concept published in 1977, I learned that you can really only EQ the direct field sound ... reverb time, room modes, reflection and peaks and nulls caused by the room will have to be addressed some other ways.
View attachment Poptronics-1977-09-OCR-Page-0041.pdf
View attachment Poptronics-1977-10-OCR-Page-0060.pdf
Now we can get close to doing this ---> compare the audio signal going into the PAmp with that at the mic/listening position and 'correct' it to be same as input signal via DSP and SW.
How cool is that?
THx-RNMarsh
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ridikas,
You're getting pretty old here. You're following the playbook others have used where snake oil is concerned. You're responses are fairly predictable.
You are going to feel awfully silly once you learn enough to find out the truth about this puddle of snakeoil called "Bybee - whatever".
-Chris
You're getting pretty old here. You're following the playbook others have used where snake oil is concerned. You're responses are fairly predictable.
Read the rules, then post. As long as you are within the guidelines you will be safe from the bin.
I'm not bullying anyone, and repeating this doesn't make it true. Those devices (resistors) were examined and tested properly and to most people's satisfaction. Because you and a few others cling blindly to the stories John and friends have cooked up doesn't invalidate those tests. to my mind, those tests completely invalidate the claims for the Bybee stuff. This "fight" is for big money. If they were $20 each I could care less. They are not, they are substantially more than that, and that becomes theft.
You are going to feel awfully silly once you learn enough to find out the truth about this puddle of snakeoil called "Bybee - whatever".
-Chris
Besides testing, did SY actually listen to the Bybee? I can't find it in that thread anymore, it's so long. If what he was able to test did not show anything and he did not hear a difference, then his review of the product is valid. However, that does not mean that someone else may not be able to hear a difference. As whatever the Bybee does may not be testable with SY's methods.
I don't cling to stories. I actually like to get out and listen for myself.
Anatech, have you actually heard a Bybee in your system?
I don't cling to stories. I actually like to get out and listen for myself.
Anatech, have you actually heard a Bybee in your system?
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Yes, he did listen to them. He has a nice system too.
Edit: He tested across the audio bandwidth. If someone sends me one, I'll test it up to 500 MHz if they want. There are other members with even better test equipment than I have, so they might be willing as well.
I'll even A-B it with an equivalent resistance that I'll measure first, and I have a friend that can hear power cords who will listen too.
-Chris
Edit: He tested across the audio bandwidth. If someone sends me one, I'll test it up to 500 MHz if they want. There are other members with even better test equipment than I have, so they might be willing as well.
I'll even A-B it with an equivalent resistance that I'll measure first, and I have a friend that can hear power cords who will listen too.
-Chris
Excellent. I hope someone reading this can send you one to try. Until then, no reason to call it snake oil.
Richard, once upon a time I was seriously going to build that unit...and then got a job working with a sound contractor and had access to an HP/Altec 8050A...thank you for having sparked my imagination with that article!! I remember it well. I do have one qualm about your construction, however: WHY A FAUX WOODGRAIN FRONT PANEL?!?!?!?! lolol
Cheers,
Howie
For the advertising claims, yes. For John's claims that packing a bunch of them closely coupled to your circuitry, probably not. Let's not lump the two together. One may turn out to be factually true, whether reasonable to actually do or not.
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