John Curl's Blowtorch preamplifier part III

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OMF'ing G ! What a train wreck! Come on guys.... update and upgrade.

And, pls dont go into comparing A and B speakers --- go to the reference -- real sounds from real known people in your listening room to start. Known voices and midrange is the best place to start and move up/down in freq from there. bring in cymbals or bell or what ever between speakers and listen to it compared to recording/playback on your system. Bring in a tuba! Make your system .. system ... sound as real as possible. That is a worthy goal IMO.

My best system was a 3 way all horn loaded... passive X-over. This is about 45 years ago. I experimented with dispersion patterns and room reflections, acoustics back then. Next best was 3 way with each side being tri-amped .. 18 inch bass in folded rear load transmission lines and full range ESL used only for midrange and RTR array of esl tweeters directly driven off the plates of tube amps (cap coupled).

Nothing since then has come close.... Until the JBL M2. A two way but I am fixing to make a sub to go with it and limit the LF range of the JBL driver. and remove the affects of the ported enclosure.

If others want to increase 'accuracy' of their system... they have to do the actual hard work... do the recorded/live over and over while doing upgrading/improving/modifying all parts of the room and hardware system.

I am in most agreement with our experienced friend, Tryphon.


THx-RNMarsh
 
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Interrupting the thread for an important scientific discovery, heaven has been found on earth.
 

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If you got a garage full of M2's, I'm sure everyone would send you their address and some shipping $.

:D

what ever. All --> Just TRY to get ever more accurate.... even improve the cross-over, if possible. Bi-amp Bi-wire. Simple Room acoustics fixes. Build your own speakers. Something, but not just do CAD and talk about what might be better/more accurate and not actually move forward in your own system.

Sigh.


THx-RNMarsh
 
Fiddling with the simulation it seems the source was 50 Ohms (not realistic at 1 KHz for AC line applications but works for the simulation). For AC applications you need caps that won't self destruct and take everything near them. There are caps specific to that task. The cap you call out should be OK for that task. The longer leads and construction will have higher ESR but should not really degrade the performance. All the caps should be rated for direct AC services. Essentially they should be "X" caps which have internal fusing to disconnect if they fail. The L's and R's around the caps are the parasitics of the caps.

This still does not answer the question, I still do not know what the mains impedance is in the patent, I still think (like you do) that the 56u for C89 is (at the least) a bit large, is this serious (a capacitor that large)? And above all I still do not know why the simulation result does not match the patent and the graphs in the patent.

Any way, at this moment I do not expect to get a true answer, and in that light you may see the question as rhetorical.

@1audio, thank for trying but the question was actually intended for RN Marsh. For now I will forget about the patent and find other documentation for mains-filter applications.
 
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Take out the 56uF cap and re-run the simulation. ;)

Yes I did, but no 20....30dB suppression (not near) there must have been a unrealistically high mains impedance in the patent schematic. I just want to know how serious this paper is and what the operating conditions for the filter are, what is the value of the patent if one can not decode the data needed to check it?

P.s. When one takes out the capacitor then a new (and possibly patentable) circuit will emerge :) yes/no :)

P.s. Are all American patents of this quality?
 
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Until the JBL M2. A two way but I am fixing to make a sub to go with it and limit the LF range of the JBL driver. and remove the affects of the ported enclosure.
@Richard, I am most interested in your drivers that makes Walys head spin. What are you using and how are you configuring it, them?

Do you have data sheet/specs will travel???? No, I don't mean sending speakers but info please.

This is going to be my next "project" after I get the mastering speakers up and running.

If others want to increase 'accuracy' of their system... they have to do the actual hard work... do the recorded/live over and over while doing upgrading/improving/modifying all parts of the room and hardware system.

THx-RNMarsh

Oh, come on Richard, what fun is that? I mean you'd be gutting a lot of the adventure that many on DIYAudio live through the work of others! And, to be the critic that points out the "err" of your limited cognitive ability and always prone to group think your way outta something.

What was that noted saying that people quote about critics?

Oh yes, give credit to the critic because it is s/he who is omnipotent and screw the wo/man who dare get in and dirty up his organ of such vile and low hung fruit. Lothe him/er and quote the raven ever more.

And listen to his heart beating from the sub-woofer....

Too hell with it, the critic proclaimed...of with it's cranium and wo/man-hood too.

How dare they curse the sacred review of their toil... ...after all, what do the know they that cannot be disputed and proven false from my own critical simulation.

How dare they, moam rath outgrabe be dammed!

Just go ask Alice, when she's ten feet tall.

Then and only then may you challenge the Critics' sacred words. Only to be stuck down again with rebuttal.

Richard, John, others, back to the toil...

And the beat goes on....

Cheers,

Gentlemen enjoy the ride.
 
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This still does not answer the question, I still do not know what the mains impedance is in the patent, I still think (like you do) that the 56u for C89 is (at the least) a bit large, is this serious (a capacitor that large)? And above all I still do not know why the simulation result does not match the patent and the graphs in the patent.

Any way, at this moment I do not expect to get a true answer, and in that light you may see the question as rhetorical.

@1audio, thank for trying but the question was actually intended for RN Marsh. For now I will forget about the patent and find other documentation for mains-filter applications.

That does not look like the original patent but one that others have played with... added switches to extend patent life etc. So, I would not be surprised if those are not the values I used, either. i have both CAD data (used in patent app) and measured - which is same as CAD.

56ufd? I never used a 56u. But if you understand that patent, you can get the results I used and produced.

Demian is correct in how this was developed ..... a digital display cheap-o table clock (later called a Tice clock) was plugged in, people heard a change in thier systems sound. One of those which purely tech types LTAO. But, I believe if so many people say they hear same thing, something is going on....

Because I have a small arsenal of test equipment, I measured the Z across the ac plug pins. I saw a dip in the Z at mid freq. Not deep but noticeable. Inside, i found the parts which were responsible for that dip.. a resonance formed with C and transformer. But I could make a better one with a few passive parts with greater atten at resonance.

It worked just fine and so I assumed if one is good, I could place several staggered across the wide freq range and atten a wider range of unwanted freqs. ETC> Its in the patent. The entire effect is large - audibly large. I took it to the head quarters of Stereophile and in thier ref system it made a dramatic change in the sound. Just plugged into the adjacent outlet their system is plugged into. Every single person at Stereophile heard the change in sound. They kept it for a long time afterwards. Eventually it became a commercial product.

It isnt suitable here to discuss without a DBLT to back it up however.... for the non-believers. Might have been fun (not) but wasnt necessary.

There are many ways to approach ac line filtering.... and yes, you need to know the ac line Z. And something about the loads. In USA, power Z is about 100 Ohms. The people the patent was assigned to couldn't build it to be reliable and Ii dont think it is sold any more..... maybe some simplified version? I am working on restarting that as a product again in Asia since the patent is long passed.

Should I?

Somewhere there is the message of a clean ac power source can help towards a more accurate playback system. In fact it has similar affect on the recording side as well. When used by a well known artist at a new studio in Canada with a new Neve console wrote back and returned the loaner saying it made a bigger improvement than their new Neve. They bought one.

There are several ways to clean up the ac line, that was one way. Further back was a noise/transient computer glitch issue we had at LLNL. it too was traced to the 3-phase ac power line. Some other time.


THx-RNMarsh
 
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Thanks, to respond

That does not look like the original patent but one that others have played with... added switches to extend patent life etc.

That explains some (the mods that do not make sense and do not do anything for the filter (like the switches))

So, I would not be surprised if those are not the values I used, either. i have both CAD data (used in patent app) and measured - which is same as CAD.

So, the original, was torpedoed. It would be nice to see the original values, I'm in the process of looking into designing a filter of myself, for this I was looking at designs other people did, this one was just one that came up.

56ufd? I never used a 56u. But if you understand that patent, you can get the results I used and produced.

Again this explains more, and yes I do understand the intentions of the filter, and yes I can figure out how to make it work, even, probably, how to enhance it.

Demian is correct in how this was developed ..... a digital display cheap-o table clock (later called a Tice clock) was plugged in, people heard a change in thier systems sound. One of those which purely tech types LTAO. But, I believe if so many people say they hear same thing, something is going on....

I did search the net and could not find what it meaning of this phrase.

Because I have a small arsenal of test equipment, I measured the Z across the ac plug pins. I saw a dip in the Z at mid freq. Not deep but noticeable. Inside, i found the parts which were responsible for that dip.. a resonance formed with C and transformer. But I could make a better one with a few passive parts with greater atten at resonance.
It worked just fine and so I assumed if one is good, I could place several staggered across the wide freq range and atten a wider range of unwanted freqs. ETC> Its in the patent. The entire effect is large - audibly large. I took it to the head quarters of Stereophile and in thier ref system it made a dramatic change in the sound. Just plugged into the adjacent outlet their system is plugged into. Every single person at Stereophile heard the change in sound. They kept it for a long time afterwards. Eventually it became a commercial product.

Lets see what I can do to make my own measurements (this will take a while :)).

It's a pity/shame that the original patent has been modified into a 'high-End folly' this is (as I see) one of the tasks of the patent office, to prevent that these 'folly's are patented. Anyway it's not my task to guard that.

It isnt suitable here to discuss without a DBLT to back it up however.... for the non-believers. Might have been fun (not) but wasnt necessary.

That's fine, ill just need some measurements as a reality-check for my simulations.

There are many ways to approach ac line filtering.... and yes, you need to know the ac line Z. And something about the loads. In USA, power Z is about 100 Ohms. The people the patent was assigned to couldn't build it to be reliable and Ii dont think it is sold any more..... maybe some simplified version? I am working on restarting that as a product again in Asia since the patent is long passed.

100 Ohms seems like excessive, I was thinking in the directions of, about a 1% drop for each 2 Amps makes for 5% at 10 Amps might be reasonable. That would be about 500 mOhm so a value between 500 mOhm (or less) and 1 Ohm may be reasonable. I will check if there is some data available for the utility company.

Should I?

:)

Somewhere there is the message of a clean ac power source can help towards a more accurate playback system. In fact it has similar affect on the recording side as well. When used by a well known artist at a new studio in Canada with a new Neve console wrote back and returned the loaner saying it made a bigger improvement than their new Neve. They bought one.

In my opinion, if a filter like this (or any other) changes the sound of an audio device, then the device must be badly designed (or broken). But there are a lot of badly designed audio (and other) devices that may or will benefit from a mains-filter, so why not supply one :)

There are several ways to clean up the ac line, that was one way. Further back was a noise/transient computer glitch issue we had at LLNL. it too was traced to the 3-phase ac power line. Some other time.

Of course, using frequency tuned constant-voltage transformers being on one end of the scale, one could use a motor/generator combo to regenerate or a SMPS high-power amplifier to regenerate. Using a filter should be the low-cost solution, as I would guess that most other solutions will be costlier.
 
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Powerline impedance at the power frequency can vary a lot depending on things like the number of transformers, distance from the generator, tightness of screw terminal blocks, etc. Interconnection screws and bolts tend to need retightening from time to time, a routine activity of electricians. There has to be a lot of existing literature on these things, I recall having seen some of it before. There is probably even a branch or subdivision of IEEE dedicated to power transmission and delivery, and maybe another for things like EMI/RFI suppression. Probably trade magazines dedicated to it as well, maybe one called Power Quality (?). All this off the top of my head, it has been awhile since I had to dig into some related issues.
 
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