Jan,
Yup, phase shift and group delay is definitely a problem, but since most amps use a differential pair as their input stage anyway, the result is probably more representative than not...
Definitely, though, if a non-distorting time/phase delay could be used, it would help.
Lieven,
You are correct about the whole system approach, but what I was getting at here are the grosser distortions introduced by an amp when driving a real signal into a real load. Get that right, and you are more than halfway towards the whole-system approach.
Bill.
P.S. The Quad amps were nice - in my book, simple is often better...
Yup, phase shift and group delay is definitely a problem, but since most amps use a differential pair as their input stage anyway, the result is probably more representative than not...
Definitely, though, if a non-distorting time/phase delay could be used, it would help.
Lieven,
You are correct about the whole system approach, but what I was getting at here are the grosser distortions introduced by an amp when driving a real signal into a real load. Get that right, and you are more than halfway towards the whole-system approach.
Bill.
P.S. The Quad amps were nice - in my book, simple is often better...
about phase shift and delay etc.
Ask any PA-man who owns a BSS omnidrive fds388 or similar.
You're far from halfway owning this and a battery of good amplifiers and loudspeakers.
Getting the right 'set-up' of a system is ( a lot) more than the addition of great equipment.
Manipulating the BSS omnidrive (and speaker set-up) the right way is an art like adjusting an acoustical instrument (in fact it is).
It's a way to slice the complex sound into less complex manipulatable entities, but don't forget the overall picture!!!
Therefore I would like to add:
Simple is often better.... mostly because we have a better grip on things that way.
woneill said:
Ask any PA-man who owns a BSS omnidrive fds388 or similar.
You're far from halfway owning this and a battery of good amplifiers and loudspeakers.
Getting the right 'set-up' of a system is ( a lot) more than the addition of great equipment.
Manipulating the BSS omnidrive (and speaker set-up) the right way is an art like adjusting an acoustical instrument (in fact it is).
It's a way to slice the complex sound into less complex manipulatable entities, but don't forget the overall picture!!!
Therefore I would like to add:
Simple is often better.... mostly because we have a better grip on things that way.
Nania,
Perhaps you can clear up some of your theory for me and others.
Can you describe how you think conventional theory describes the situation (amp driving speaker) first?
Then you can describe how your theory treats the situation.
If you emphasize the differences between the theories, perhaps others can understand the truths and advantages available.
Remember, astronomers had been using a heliocentric model for years before Galileo. The numbers were much easier to calculate, but they still believed in the geocentric model.
Give us your "heliocentric" model.
Thanks,
-Dan
Perhaps you can clear up some of your theory for me and others.
Can you describe how you think conventional theory describes the situation (amp driving speaker) first?
Then you can describe how your theory treats the situation.
If you emphasize the differences between the theories, perhaps others can understand the truths and advantages available.
Remember, astronomers had been using a heliocentric model for years before Galileo. The numbers were much easier to calculate, but they still believed in the geocentric model.
Give us your "heliocentric" model.
Thanks,
-Dan
Wow, I just joined this forum and can't believe the great stuff on here. I want to get up to speed on this guys theory so if you guys can help me that would be great. First off, his theory reads different on the first page and I haven't a clue what he's trying to say there, is the restatement just an edit or a change in Nania's Theory? This guy is way out there but this is some original idea, no?
Next, it sounds like he's saying that because there are frequencies and amplitude in a music signal, it can be defined as a sort of power but power is only dissipated through a resistance with volts x amps as the variables but since a speakers impedance is constantly changing, we can't use Ohm's law reliably. Would it help his calculations if he were to assign an imaginary constant as the representation of the speaker load and use derivative functions to make a vector model of the component volts x amps? This is starting to sound a little less crazy to me, maybe I'm losing it too but this sounds mathematically doable.
Last, he says something interesting when he compares a speakers impedence to an object on a parabola. This is where I got hooked and think there might be some real genius here. The source sends volts/time to the amp which could also be thought of as a sound wave with constituent frequencies. That wave can be fractured or its frequency components misaligned by the amplification or the drivers but he is specific in saying that its the current component which maintains the integrity. This is definitely upside down thinking but check it out, this explains why even good amps collapse their image when you turn up the gain. The volts do increase but the current fails to hold on to the drivers! This Nania guy is a trip! Have I got this right or am reading him wrong?
Next, it sounds like he's saying that because there are frequencies and amplitude in a music signal, it can be defined as a sort of power but power is only dissipated through a resistance with volts x amps as the variables but since a speakers impedance is constantly changing, we can't use Ohm's law reliably. Would it help his calculations if he were to assign an imaginary constant as the representation of the speaker load and use derivative functions to make a vector model of the component volts x amps? This is starting to sound a little less crazy to me, maybe I'm losing it too but this sounds mathematically doable.
Last, he says something interesting when he compares a speakers impedence to an object on a parabola. This is where I got hooked and think there might be some real genius here. The source sends volts/time to the amp which could also be thought of as a sound wave with constituent frequencies. That wave can be fractured or its frequency components misaligned by the amplification or the drivers but he is specific in saying that its the current component which maintains the integrity. This is definitely upside down thinking but check it out, this explains why even good amps collapse their image when you turn up the gain. The volts do increase but the current fails to hold on to the drivers! This Nania guy is a trip! Have I got this right or am reading him wrong?
Nania,
Here are my thoughts on your theory.
Take the following as given:
- The speaker cone is driven only by the current through the voice coil of the speaker (The resonance of the air in the box driving the cone motion will be taken as a special case).
- The motion of the cone will be proportional to the current as long as the voice coil stays within the magnetic gap (ignoring the non-linearities of the suspension, air load and other minor factors).
- The current through the voice coil is determined by the applied voltage and the dynamic impedance of the voice coil.
- The impedance of the voice coil is made up of the DC resistance and inductive reactance (the phase angle between the applied voltage and the resultant current is between 0 and 90degrees, current lagging. Also ignoring Maggies and other capacitive type speakers).
All of the above statements are true with reasonable qualifications.
The Goal:
Given a music signal and the above statements, it is required that the cone be driven by a current signal exactly proportional to the music signal to obtain an accurate acoustic reproduction of the original music signal (electrical – to – mechanical – to – acoustical).
Conclusions:
The only independent variable is voltage. If the appropriate voltage could be applied at the appropriate time, the current would be “forced” to follow the original music signal.
Since the applied voltage is independent, we are free to apply (design an amplifier to deliver) as high a voltage as is available to us to “force” the current through the voice coil. This is only possible by the use of feedback, either motional feedback, or current feedback.
The Nania Theory:
I know, to you your theory “feels” right. It does to me as well. It’s the whole conservations of energy thing. I believe that if the above were successfully applied and you were able to measure the dynamic power delivered to the speaker and the dynamic reverse EMF, you would find the sum to be the power required to reproduce the original music signal minus the resistive losses and minor non-linearities.
I hope this doesn’t confuse matters, but it’s the way I see it. I know your in the penalty box serving a two minute minor, but if I hit a note email me and let me know.
rodyama@comcast.net
Rodd Yamas***a
Here are my thoughts on your theory.
Take the following as given:
- The speaker cone is driven only by the current through the voice coil of the speaker (The resonance of the air in the box driving the cone motion will be taken as a special case).
- The motion of the cone will be proportional to the current as long as the voice coil stays within the magnetic gap (ignoring the non-linearities of the suspension, air load and other minor factors).
- The current through the voice coil is determined by the applied voltage and the dynamic impedance of the voice coil.
- The impedance of the voice coil is made up of the DC resistance and inductive reactance (the phase angle between the applied voltage and the resultant current is between 0 and 90degrees, current lagging. Also ignoring Maggies and other capacitive type speakers).
All of the above statements are true with reasonable qualifications.
The Goal:
Given a music signal and the above statements, it is required that the cone be driven by a current signal exactly proportional to the music signal to obtain an accurate acoustic reproduction of the original music signal (electrical – to – mechanical – to – acoustical).
Conclusions:
The only independent variable is voltage. If the appropriate voltage could be applied at the appropriate time, the current would be “forced” to follow the original music signal.
Since the applied voltage is independent, we are free to apply (design an amplifier to deliver) as high a voltage as is available to us to “force” the current through the voice coil. This is only possible by the use of feedback, either motional feedback, or current feedback.
The Nania Theory:
I know, to you your theory “feels” right. It does to me as well. It’s the whole conservations of energy thing. I believe that if the above were successfully applied and you were able to measure the dynamic power delivered to the speaker and the dynamic reverse EMF, you would find the sum to be the power required to reproduce the original music signal minus the resistive losses and minor non-linearities.
I hope this doesn’t confuse matters, but it’s the way I see it. I know your in the penalty box serving a two minute minor, but if I hit a note email me and let me know.
rodyama@comcast.net
Rodd Yamas***a
roddyama said:
Nania, I'm sorry that your theory have to be proved otherwise theory is theory and not facts.
The loudspeaker is always a complex load and therefore it "swallow" energy and also give back in the wires and SOME gets out as accustic energy. I don't understand "power profile" at all!
Can you really really explain it for me?
As roddyama stated there are indeed advantages to current driving loudspeakers. It will eliminate the effects of the voice-coil inductance.
One has to keep in mind that the inductance not only limits transient response it is also excursion dependant in a non linear fashion. Some drivers are better, some are worse in this respect.
If a driver is current driven also the increase in resistance, caused by temperature rise in it's voice coil, is compensated for.
As always there is also a downside: We will now loose control over the cone's damping around fs. But this can be accounted for by using voltage drive around fs and current drive above.
Maybe a horn would give enough mechanical damping to implement current drive over the whole frequency range, I don't know.
To be able to apply such things properly we have to go active.
I am risking to be shot but in my opinion there is no technical reason to use or build passive loudspeakers anymore today.
Regards
Charles
One has to keep in mind that the inductance not only limits transient response it is also excursion dependant in a non linear fashion. Some drivers are better, some are worse in this respect.
If a driver is current driven also the increase in resistance, caused by temperature rise in it's voice coil, is compensated for.
As always there is also a downside: We will now loose control over the cone's damping around fs. But this can be accounted for by using voltage drive around fs and current drive above.
Maybe a horn would give enough mechanical damping to implement current drive over the whole frequency range, I don't know.
To be able to apply such things properly we have to go active.
I am risking to be shot but in my opinion there is no technical reason to use or build passive loudspeakers anymore today.
Regards
Charles
New theory etc
Nania,
I have been reading your theory several times, and I really have trouble understanding what you are saying.
It would help very much if you could say:
- why is current theory not OK? does Ohms law break down in a speaker? How do you know?
- did you just dream up this theory or do you have *some* indications that it works as you think? Why is voltage *slap*, and not current? Maybe it's just the other way around? Why not? Come to think of it, what the (censure) is slap?
You are proposing a very extreme theory, and that will need extremely strong proof that you are right. Somehow, since you ask *us* how this can be proven, I am not optimistic
The fact that Newtonian Physics was wrong doesn't mean that Ohms law is also wrong. In fact, this has nothing to do with it. It is however a method often used to influence people to believe there is something while there isn't.
Jan Didden
Nania,
I have been reading your theory several times, and I really have trouble understanding what you are saying.
It would help very much if you could say:
- why is current theory not OK? does Ohms law break down in a speaker? How do you know?
- did you just dream up this theory or do you have *some* indications that it works as you think? Why is voltage *slap*, and not current? Maybe it's just the other way around? Why not? Come to think of it, what the (censure) is slap?
You are proposing a very extreme theory, and that will need extremely strong proof that you are right. Somehow, since you ask *us* how this can be proven, I am not optimistic
The fact that Newtonian Physics was wrong doesn't mean that Ohms law is also wrong. In fact, this has nothing to do with it. It is however a method often used to influence people to believe there is something while there isn't.
Jan Didden
Hi Charles,
This thread is in the Pass Labs forum, and it now appears, rightfully so.
If you look at the Aleph schematic, it is using current feedback by the voltage across the parallel shunt resistors at its output. Also the FETs are current sourcing devices, so the Aleph can be looked at as a "current drive" type amp (correct me if I'm off-base here). So from this we should have the senario I described earlier, in this case using current feedback.
So why does it not fail at the drivers resonance? Shouldn't the current feedback try to force more current through the resonating speaker and overdrive it?
It does not do this. As a matter of fact, it provides just enough current to drive the speaker cone to its designed flat response. The only way I can explain this (and I may be wrong) is that there is a balance that is achieved between the current drive of the amp and the reverse EMF of the resonating speaker. Simply stated, the inductive reactatance at resonance is greater than the amps ability to provide more current. It would further seem that it is the box tuning that actually controls the acoustic response in this frequency range.
The question remains, does this fall inline with Nania's "Power Profile"? I'm not sure. I must think some more.
Rodd Yamas***a
This thread is in the Pass Labs forum, and it now appears, rightfully so.
If you look at the Aleph schematic, it is using current feedback by the voltage across the parallel shunt resistors at its output. Also the FETs are current sourcing devices, so the Aleph can be looked at as a "current drive" type amp (correct me if I'm off-base here). So from this we should have the senario I described earlier, in this case using current feedback.
So why does it not fail at the drivers resonance? Shouldn't the current feedback try to force more current through the resonating speaker and overdrive it?
It does not do this. As a matter of fact, it provides just enough current to drive the speaker cone to its designed flat response. The only way I can explain this (and I may be wrong) is that there is a balance that is achieved between the current drive of the amp and the reverse EMF of the resonating speaker. Simply stated, the inductive reactatance at resonance is greater than the amps ability to provide more current. It would further seem that it is the box tuning that actually controls the acoustic response in this frequency range.
The question remains, does this fall inline with Nania's "Power Profile"? I'm not sure. I must think some more.
Rodd Yamas***a
phase_accurate & lieven
I agree, I think that the only way to accuratly reproduce the electrical signal from the source as waves in air is to use an intigrated system. This would allow for a feedback system from the output transducer back to the signal source.
The problem is how many "active speakers" have been marketed and failed because you can't use that superwizbang XYZ amplifer with them or the ultimate PDQ driver and the OMG speaker cables.
This brings me back to this "ninia power theory" way too many varibles. How many models of speakers are there, not brands folks, models. Every one has a different impedance/frequency plot. Does anyone remember ELI the ICE man from just after learning E=IR.
In a voltage amplifier which is the most common type used today the amplifier can only present a voltage to the load. The load not the amplifier determines the amout of current that flows in this series circuit. It is a series circuit by the way( power supply, output device, complex speaker load and back to the power supply) and this was the simplest possible circuit.
I hope I didn't confuse anyone other than myself here.
Later Bruce
I agree, I think that the only way to accuratly reproduce the electrical signal from the source as waves in air is to use an intigrated system. This would allow for a feedback system from the output transducer back to the signal source.
The problem is how many "active speakers" have been marketed and failed because you can't use that superwizbang XYZ amplifer with them or the ultimate PDQ driver and the OMG speaker cables.
This brings me back to this "ninia power theory" way too many varibles. How many models of speakers are there, not brands folks, models. Every one has a different impedance/frequency plot. Does anyone remember ELI the ICE man from just after learning E=IR.
In a voltage amplifier which is the most common type used today the amplifier can only present a voltage to the load. The load not the amplifier determines the amout of current that flows in this series circuit. It is a series circuit by the way( power supply, output device, complex speaker load and back to the power supply) and this was the simplest possible circuit.
I hope I didn't confuse anyone other than myself here.
Later Bruce
Since you guys have ignored my questions, I guess they must have sounded pretty stupid to you all so I'm sorry if I don't get it yet but it would've been nice to be acknowledged. Alot of what came after my questions is way over my head so if you please, I'd like to start catching up.
What is a current drive and does it exist only in an amp?
When you guys talk about feedback loops do you mean the EMF feedback of the moving coils or the electronic feedback in the amp?
On the first page of this thread Nania Theory states "current" times amplitude makes up the Audio Power but when restated on page 5 he states that it's frequencies time amplitude: does he use current and frequency interchangably or is this an edit?
I'm sorry if I seem like a dumb *** but somebody please help?
What is a current drive and does it exist only in an amp?
When you guys talk about feedback loops do you mean the EMF feedback of the moving coils or the electronic feedback in the amp?
On the first page of this thread Nania Theory states "current" times amplitude makes up the Audio Power but when restated on page 5 he states that it's frequencies time amplitude: does he use current and frequency interchangably or is this an edit?
I'm sorry if I seem like a dumb *** but somebody please help?
OK, being new to the forum, I suppose you deserve a
courteous response.
To quote from your original posting:
"Next, it sounds like he's saying that because there are frequencies and amplitude in a music signal, it can be defined as a sort of power but power is only dissipated through a resistance with volts x amps as the variables but since a speakers impedance is constantly changing, we can't use Ohm's law reliably."
Maybe not Ohms law exclusively, but there is more than
enough analytical capacity to quantitatively describe what
is going on in a driven loudspeaker.
"Would it help his calculations if he were to assign an imaginary constant as the representation of the speaker load and use derivative functions to make a vector model of the component volts x amps?"
Imaginary values is precisely how we describe reactive
out of phase phenomena.
"Last, he says something interesting when he compares a speakers impedence to an object on a parabola. This is where I got hooked and think there might be some real genius here. The source sends volts/time to the amp which could also be thought of as a sound wave with constituent frequencies."
Any wave is describable as a sum of constituent frequencies,
each with its own amplitude and phase.
"That wave can be fractured or its frequency components misaligned by the amplification or the drivers but he is specific in saying that its the current component which maintains the integrity."
I am unaware of any evidence that somehow the "current
maintains the integrity". The relationship between current,
voltage, time, and the load is fixed. If you know 3 of the
values, you know the 4th.
"This is definitely upside down thinking but check it out, this explains why even good amps collapse their image when you turn up the gain."
It doesn't explain it to me at all.
"The volts do increase but the current fails to hold on to the drivers!"
There is no scenario where the volts will be able to vary
into a nominal load without being supported by current.
To respond to your latest post:
Current drive is presumably driving the amplifier with current
which is linearly proportional to the input, regardless of load.
Audio power, that is to say that which becomes acoustic
power from a loudspeaker, is a complex of voltage and
current, and is not described so simply, but on the other
hand it is not a big mystery.
Does that help?
courteous response.
To quote from your original posting:
"Next, it sounds like he's saying that because there are frequencies and amplitude in a music signal, it can be defined as a sort of power but power is only dissipated through a resistance with volts x amps as the variables but since a speakers impedance is constantly changing, we can't use Ohm's law reliably."
Maybe not Ohms law exclusively, but there is more than
enough analytical capacity to quantitatively describe what
is going on in a driven loudspeaker.
"Would it help his calculations if he were to assign an imaginary constant as the representation of the speaker load and use derivative functions to make a vector model of the component volts x amps?"
Imaginary values is precisely how we describe reactive
out of phase phenomena.
"Last, he says something interesting when he compares a speakers impedence to an object on a parabola. This is where I got hooked and think there might be some real genius here. The source sends volts/time to the amp which could also be thought of as a sound wave with constituent frequencies."
Any wave is describable as a sum of constituent frequencies,
each with its own amplitude and phase.
"That wave can be fractured or its frequency components misaligned by the amplification or the drivers but he is specific in saying that its the current component which maintains the integrity."
I am unaware of any evidence that somehow the "current
maintains the integrity". The relationship between current,
voltage, time, and the load is fixed. If you know 3 of the
values, you know the 4th.
"This is definitely upside down thinking but check it out, this explains why even good amps collapse their image when you turn up the gain."
It doesn't explain it to me at all.
"The volts do increase but the current fails to hold on to the drivers!"
There is no scenario where the volts will be able to vary
into a nominal load without being supported by current.
To respond to your latest post:
Current drive is presumably driving the amplifier with current
which is linearly proportional to the input, regardless of load.
Audio power, that is to say that which becomes acoustic
power from a loudspeaker, is a complex of voltage and
current, and is not described so simply, but on the other
hand it is not a big mystery.
Does that help?
Hi roddyama
Your Aleph's output impedance is still lower than the load's impedance so it is a good approximation of a voltage source. I.e. it is supplying a voltage at it's output and the current has to follow accordingly.
If your amplifier was a current source then it's output impedance would IDEALLY be infinite (so would it's output voltage under a no load condition). That's the reason why you would loose control over the driver's resonant behaviour. But the grip on your driver will be increased at high frequencies where the voice coil inductance is acting as a first order lowpass.
If your amplifier is a current source then this effect is eliminated.
As usual this has also disadvantages: If driven by fast transients a real amplifier might get into voltage saturation quite easily (due to the fact that a current through an inductor can't rise infinitely fast).
If anybody is interested I can supply simulation results, but maybe not in the passlabs forum because this might be regarded as an offence.
Regards
Charles
P.S.:
Regarding the Nania Theory, I too have problems in understanding why a current should be guidiong a voice coil and voltage should represent something like kicking. Whatever you do, Ohm's law will allways apply.
Your Aleph's output impedance is still lower than the load's impedance so it is a good approximation of a voltage source. I.e. it is supplying a voltage at it's output and the current has to follow accordingly.
If your amplifier was a current source then it's output impedance would IDEALLY be infinite (so would it's output voltage under a no load condition). That's the reason why you would loose control over the driver's resonant behaviour. But the grip on your driver will be increased at high frequencies where the voice coil inductance is acting as a first order lowpass.
If your amplifier is a current source then this effect is eliminated.
As usual this has also disadvantages: If driven by fast transients a real amplifier might get into voltage saturation quite easily (due to the fact that a current through an inductor can't rise infinitely fast).
If anybody is interested I can supply simulation results, but maybe not in the passlabs forum because this might be regarded as an offence.
Regards
Charles
P.S.:
Regarding the Nania Theory, I too have problems in understanding why a current should be guidiong a voice coil and voltage should represent something like kicking. Whatever you do, Ohm's law will allways apply.
Hi Lieven
Maybe I am a bit hard of understanding, but what do you mean by NP-BC ??😕
Regards
Charles
Maybe I am a bit hard of understanding, but what do you mean by NP-BC ??😕
Regards
Charles
a pass-carver like thing.
call it a high headroom two stage amp.
aleph is voltage-scalable, so needs a bit of carver-tech to add.
call it a high headroom two stage amp.
aleph is voltage-scalable, so needs a bit of carver-tech to add.
Hi lieven
In this context the crossover thingy between class A and class G crosses my mind which is used in the new Meyer active studio monitors.
But it has still nothing to do with current drive.
But you could make any amplifier behave like a current source by changing the feedback topology.
If your system is active then the voltage headroom doesn't have to be ridiculously high since it is proportional to the input slew-rate AND the voice-coil inductance.
The latter one isn't that high for tweeters usually.
Regards
Charles
In this context the crossover thingy between class A and class G crosses my mind which is used in the new Meyer active studio monitors.
But it has still nothing to do with current drive.
But you could make any amplifier behave like a current source by changing the feedback topology.
If your system is active then the voltage headroom doesn't have to be ridiculously high since it is proportional to the input slew-rate AND the voice-coil inductance.
The latter one isn't that high for tweeters usually.
Regards
Charles
you don't need a lot of horse-power to move a bike faster than a porsche, not to speak of a truck.
Mr Pass' collegue argument of building a turbo-amp is that we don't allways need the torque of a truck, but sometimes it's handy to have it for a few moments.
btw: nice, those meyer x-10's, would like to hear them.
1200 w is a lot, correction (FFFFFFFeedback) will cause high demands on amps.
Mr Pass' collegue argument of building a turbo-amp is that we don't allways need the torque of a truck, but sometimes it's handy to have it for a few moments.
btw: nice, those meyer x-10's, would like to hear them.
1200 w is a lot, correction (FFFFFFFeedback) will cause high demands on amps.
Charles,
I think I’m starting to get my brain around the interface between the amp and the speaker. This is, after all the heart of this issue. I guess I’m also starting to see there’s not a whole lot of new ideas out there, at least not as much as we might like to think there is.
Thanks for your patience.
Rodd Yamas***a
I can agree with this. I guess I would call it a “Voltage Controlled” amplifier because it seems to me that an amplifier is always sourcing current, but I can certainly accept the standard terminology. The controlling voltage (to the limits of the rail voltage) is an amplification of the original music signal altered by the current feedback. This presents a voltage to the speaker’s impedance causing the current to flow, as you say “accordingly”.
I can agree with this as well. A real life example would be the battery. The voltage is, for practical purposes, fixed and the battery becomes a true current source. It would be the load in this case, not voltage, that controls the current. You would need to alter the load impedance or the output impedance of the amp in order to make the current replicate the original music (I get the feeling that some part of this concept might be behind Mr. Pass’ Stasis amplifiers.)
The current lag can be minimized if the voltage applied to the speaker is large enough (limited by the rail voltage). I assume this is what the feedback circuit is attempting to do in the voltage source configuration.
I think I’m starting to get my brain around the interface between the amp and the speaker. This is, after all the heart of this issue. I guess I’m also starting to see there’s not a whole lot of new ideas out there, at least not as much as we might like to think there is.
Thanks for your patience.
Rodd Yamas***a
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