No, Garth found this old console and some old RCA boards and we combined the two, the boards were rebuilt with a new circuit of our own which featured parafeed output transformers. This was the trickiest part as by nature it does not have a lot of headroom, so you have to be careful in use - and it's great on vocal so the engineer has to do a little coaching with the performer. But it was a trade-off as it was the best sound and from a creative point of view, this is a sort of instrument too and shouldn't be thought off in the same light as equipment we would use at home. This is completely different from our RTP Preamp which was an all-out attempt at a clean state-of-the art stereo tube preamp as was used by Peter Gabriel according to Allen (only he and I made them). Garth scoured his collection of vintage transformers so we could fit three pairs - six channels, for obvious reasons. The HT power supply was a massive version of our VSE SuperReg.
Somewhere there is a stereo RTP preamp with inbuilt M-S matrix. I know it was used by Barry Wolifson before he went to the States and joined Chesky. I wonder where that is now? It really was one of a kind. It surely must still be in use somewhere?
Mate, I have to get some work done here, hard when you get distracted...
Scientific proof doesn't work for audiophiles, common sense
neither, then the only thing that remains to get rid of the
evil (XO filter) is to ban the evil.
I know it's the wrong word that has no place here but it's not mine,
and I'm pretty sure it was taken out of the context to prove a point
that is not proven, without any looking back if the quoted saying is doing
harm to one's reputation.
I do have a suggestion for all of you who believe the XO filters are evil.
Don't use them at all, just pyle up drivers you'd like to use and hope
for the best. I know your amp won't like it.
I am sorry to see that normal people are being forced to believe in a
nonsense ( impedance peak of a driver is also evil). Well, if we are going
to be correct all the way about banning evil, than the usual moving coil
drivers should also be treated in the same manner, because they are
a filter, which some manufacturers have used to ban the inductors from
crossovers to prove a point. Use evil to cast out evil.
My Lord would disagree!
p.s. This thread is actually very useful and entertaining!
Look at Joe's suggestion on evil XO filter part! When you build your
filter with evil parts, them make sure it is the best evil!
This has nothing to do with marketing. We just want the users
to be uneducated and willing to spend their money on a frequent basis.
neither, then the only thing that remains to get rid of the
evil (XO filter) is to ban the evil.
I know it's the wrong word that has no place here but it's not mine,
and I'm pretty sure it was taken out of the context to prove a point
that is not proven, without any looking back if the quoted saying is doing
harm to one's reputation.
I do have a suggestion for all of you who believe the XO filters are evil.
Don't use them at all, just pyle up drivers you'd like to use and hope
for the best. I know your amp won't like it.
I am sorry to see that normal people are being forced to believe in a
nonsense ( impedance peak of a driver is also evil). Well, if we are going
to be correct all the way about banning evil, than the usual moving coil
drivers should also be treated in the same manner, because they are
a filter, which some manufacturers have used to ban the inductors from
crossovers to prove a point. Use evil to cast out evil.
My Lord would disagree!
p.s. This thread is actually very useful and entertaining!
Look at Joe's suggestion on evil XO filter part! When you build your
filter with evil parts, them make sure it is the best evil!
This has nothing to do with marketing. We just want the users
to be uneducated and willing to spend their money on a frequent basis.
Attachments
If you are using a current amp it is a big problem, as the frequency response of the speaker is directly affected by the impedance. A rise in impedance causes a rise in the frequency response.
dave
Very odd attitude - reminds me of when I was a kid and the warnings of communists under the bed.
Nobody has commented on this, repeatedly asked:
Current source (270 Ohm) versus voltage source (0 Ohm).
Question, if when driven by current (270 Ohm) and both drivers looking back are not seeing 0 Ohm and yet are behaving as if they were.
Can somebody please explain that?
Something not explained is happening here and you guys are avoiding it?
The gauntlet has been thrown down, any takers?
Current source (270 Ohm) versus voltage source (0 Ohm).
Question, if when driven by current (270 Ohm) and both drivers looking back are not seeing 0 Ohm and yet are behaving as if they were.
Can somebody please explain that?
Something not explained is happening here and you guys are avoiding it?
The gauntlet has been thrown down, any takers?
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Ohm's Law. As several people have pointed out, a flat impedance curve makes frequency response independent of source impedance. Old stuff, but valid.
I'm still fascinated by the claim of a Kirchoff's violation, since that violates continuity and would overturn basic physics. Or was that another "place holder" like "crossover noise"?
I'm still fascinated by the claim of a Kirchoff's violation, since that violates continuity and would overturn basic physics. Or was that another "place holder" like "crossover noise"?
Classic straw man argumentation - Stu is up to his old tricks again - nothing I have said is any violation of what he calls 'continuity' - absolutely said NOTHING of the kind. I do in fact have a reasonable grasp of physics, so I have never "violated" anything - and you will find that I have not used the "violate" word on any post.
Anybody can Google the subject... lol.
Note Post #77:
"I don't want to leave the impression that KL and TT has no place, it does..."
GOTCHA !!!
So now I am owed an apology.
Stuart doesn't realise that when he got obsessed with he 'noise' word and quoted me out of context, that I decided to lay a little trap for him, so I mentioned Kirckhoff's Law because be brought it up in an early message and said to myself, he won't be able to help himself, he thinks I am ignorant on the subject; I am now so familiar with his predictable tricks - and he did bite, didn't he? Got off the 'noise' word realising that he had traveled as far with that as it goes - so I baited him. Gave him another morsel, he is not so smart as he thinks he is. He fell for it.
As Dave said to him directly and accused Stuart of "conducting a with-hunt" against me - that post has never been removed, one Moderator against another.
Have we turned DiyAudio into trolls paradise? And a "Moderator" leading the charge?
We are not supposed to be disrespectful towards a Moderator or you end up in the sin bin. When I and others complain about Stuart, and the number is now legion, we are told he is only posting in the capacity of a member. This no longer has any merit, no more than a policeman misbehaving and bringing other police into disrepute because he is off duty. This simply does not wash.
I don't violate any laws of the universe, whether on the atomic or the quantum level - I am not God.
A wise man said that a braggart is one who puts other people down and elevates himself. I have seen no better example and as Solomon wrote "Pride is before a crash and a haughty spirit before stumbling."
Anybody can Google the subject... lol.
Note Post #77:
"I don't want to leave the impression that KL and TT has no place, it does..."
GOTCHA !!!
So now I am owed an apology.
Stuart doesn't realise that when he got obsessed with he 'noise' word and quoted me out of context, that I decided to lay a little trap for him, so I mentioned Kirckhoff's Law because be brought it up in an early message and said to myself, he won't be able to help himself, he thinks I am ignorant on the subject; I am now so familiar with his predictable tricks - and he did bite, didn't he? Got off the 'noise' word realising that he had traveled as far with that as it goes - so I baited him. Gave him another morsel, he is not so smart as he thinks he is. He fell for it.
As Dave said to him directly and accused Stuart of "conducting a with-hunt" against me - that post has never been removed, one Moderator against another.
Have we turned DiyAudio into trolls paradise? And a "Moderator" leading the charge?
We are not supposed to be disrespectful towards a Moderator or you end up in the sin bin. When I and others complain about Stuart, and the number is now legion, we are told he is only posting in the capacity of a member. This no longer has any merit, no more than a policeman misbehaving and bringing other police into disrepute because he is off duty. This simply does not wash.
I don't violate any laws of the universe, whether on the atomic or the quantum level - I am not God.
A wise man said that a braggart is one who puts other people down and elevates himself. I have seen no better example and as Solomon wrote "Pride is before a crash and a haughty spirit before stumbling."
Very odd attitude - reminds me of when I was a kid and the warnings of communists under the bed.
You and others who agree that crossovers are evil don't really know what
evil is. You don't know the right word for it, so in hope of that people are
going to believe your philosophy, you are using an inappropriate term
just to win over crowds for you.
The great truth about evil is than you can't be against it by accepting some
of its parts. Either you embrace it as a whole or you reject it as a whole.
You can't sit on two chairs at the same time and be regarded as reasonable
at the same time.
Your whole approach is to present yourself as a more superior individual
than other speaker designers. Dr. Joseph D'Appolito and people that
assisted him in designing Usher S 520 are automatically shown in the
light of being imcompetent when it comes to speaker design.
Because there is so many S520's out there sold at a reasonable price,
you are hoping to get as much applause for your modification glorifying
yourself in the process.
If you were truly a gentleman and a great designer, you'd be humble
and you would be much more careful when judging other people's
competence and focus on the matter that is of your interest and that
is to flatten loudspeaker impedance to make it "current amp" friendly.
To flatten out impedance is a worthy cause in this case. That was clear
from the very beginning to all those who know a bit about this.
That you twist things around when it comes to discussing is a fact
easily detected. Something for you to reflect on. Remember, the term
evil was not introduced by myself, but it was supported by you.
"We are not supposed to be disrespectful towards a Moderator or you end up in the sin bin. When I and others complain about Stuart, and the number is now legion, we are told he is only posting in the capacity of a member. This no longer has any merit, no more than a policeman misbehaving and bringing other police into disrepute because he is off duty. This simply does not wash."
Do grow up, Joe! That is hogwash and you are sounding like a little boy complaining to mummy that the big boys are disagreeing with him!
I'm sure you have interesting things to say, but the S/N ratio is very poor.
Do grow up, Joe! That is hogwash and you are sounding like a little boy complaining to mummy that the big boys are disagreeing with him!
I'm sure you have interesting things to say, but the S/N ratio is very poor.
I tend to agree with you. Joe has a history of claiming stuff as his own, as shown by naming well-known stuff to his own name; this thread name is further evidence that the humble position you mentioned is not happening.
It is also known that he makes money from modifications he introduced (as if he invented it) here. Still no problem with me; I am sure I unwittingly spend money on the equivalent of snake oil - not the end of the world.
But Joe, when you bring your particular version of technology to this forum which is known for it's pendant for facts and figures, OF COURSE people want to know where your beef is! And if it is not forthcoming, you get all kind of flak.
So, sorry, but either you live with it or port your stuff to a place that is less rigorous. The issue is fairly simple but won't go away with complaining.
My € 0.02 worth.
Late edit: Let me give you an example how this would go, with no malice intended from anyone. My reaction to your claim of 'noise' from xovers was similar to others here. 'Noise' has a very specific meaning in (audio) electronics. So if you mention it as the driving factor for your work, it is quite reasonable for people to ask what you mean by that. And I and others still have no idea what you meant, and neither do you yourself, from the signals we get ('placeholder' wtf?), so what does that do to your credibility you think?
Jan
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Joe
The post SY has a question about is post #76, not post #77. You stated in the second paragraph from the bottom
"Somebody here invoked Kirchoff's Law, but there are reasons why Kirchoff's Law doesn't quite work and is faced by things that make it fall apart in this instance."
The question SY has is when Kirchoff's Law doesn't work. Please explain.
Jay
The post SY has a question about is post #76, not post #77. You stated in the second paragraph from the bottom
"Somebody here invoked Kirchoff's Law, but there are reasons why Kirchoff's Law doesn't quite work and is faced by things that make it fall apart in this instance."
The question SY has is when Kirchoff's Law doesn't work. Please explain.
Jay
Sorry Stuart, just trying to explain the Group Dynamics here
I'm more interested in the technical claims. "Crossover noise" and Kirchoff Law violations. And yes, I know your favorite expression: "Stop being such a scientist!"
Hi Jay
Gladly.
It's very simple - nobody is denying Kirchhoff's Law is for real and I believe clearly that I am being quoted out of context.
I have clearly spelled out that something further needs to explain that an impedance can be dynamically changed by EMF that are motional, inductive and microphonic and that it affects negatively the V/I conversion that has to take place across the terminals of a loudspeaker. That whole topic must take in a host of factors, one of which is KL, but KL in itself is not sufficient.
That is all. Yet I still get accused of something I clearly pointed out I did not in Post #77 and I said "to protect myself" because I knew what was coming.
How that can be interpreted the wrong way would have to be a deliberate misconstruing what I said.
Please note, these people have form and been stalking me all over DiyAudio and especially when I post a new DIY project like this, an alternative crossover to a commercial speaker that people can try and is reversible if they don't like it. Then the 'usual suspects' turn up and we see the same thing happen all over again.
I am about to soon post a project of how to use high frequency bias in tube output transformers (a lapsed patent from the early 40's). The same pattern will repeat. The 'usual suspects' will turn up, find a phrase or word they can pick on and away we go again. Like I said, they have form on this and are repeat offenders.
Others who come in tangentially into a discussion, like it looks like you have just done, don't seem to see the whole picture, so they get sucked in too. The psychology works to the advantage of trolls (studies have shown this to be the case).
It is really sad as we are seeing a minority who have taken over DiyAudio and behind the scenes, speaking personally to some of the other Moderators, they are aware of this and sick of it. There are a LOT of upset people out there that will no longer contribute and they say it's about the trolling.
This is about a DIY project re the Usher S520 loudspeaker - that is the topic!!!
It is not about what is acceptable orthodoxy, it is not even a science forum. Now watch how they will twist that as well - DIY is about science, but it is not solely about science. So here we can twist things out of context again. And this is their tactic.
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