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Post by leonski on Oct 1, 2020 18:37:07 GMT -5
Almost everybody here talks like they own a huge successful audio company and they are the lead engineer also 😂 How'd YOU know?  |
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Post by brutiarti on Oct 1, 2020 21:03:55 GMT -5
Almost everybody here talks like they own a huge successful audio company and they are the lead engineer also 😂 How'd YOU know?  Send me a link and I will buy some of the products to evaluate |
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Post by leonski on Oct 1, 2020 22:23:41 GMT -5
I worked for 30+ years in a very technical field. Semiconductor and Integrated circuit manufacture.
So I kind of approach stuff from a different viewpoint than most. To this day, I can't use a PENCIL.....
which I can just imagine the dust / particles shedding off as you write. Even 'clicky' pens were not allowed in
a clean room. Dust was measured as number / size of particle per cubic foot and must be LOW.
I did SOME teaching, too. Mainly implant, diffusion and sometimes photolighography and even thin films / sputter.
As such in my position, I HAD to know stuff. And frequenctly how to fix the process or make adjustments.
I'm fairly inventive, good at photography but DO NOT have the complete skillset to start and run a business.......
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Post by creimes on Oct 1, 2020 22:48:31 GMT -5
One thing I don't understand is how much an amp that costs a mere $999 can be examined and critiqued so hard to the point of some thinking it's a complete waste of their money yet the pair of monoblocks on the list for a staggering $188,000 don't get any criticism at all, like seriously $188,000 is almost as much as my house, well actually it would prob cost more than my home due to the fact I'm in Canada and that's a US price tag, I actually find that completely pathetic but hey that's the world we live in right. So does the XPA-2 actually sound like a transistor if you have the chance to listen to gear costing that much, I highly doubt it. Since my value of money is obviously wayyyyyy different than the guy spending $200,000 on amps I would think those amps sound like garbage considering their cost haha. I guess only the rich can truly get great sounding systems ??
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Post by rbk123 on Oct 2, 2020 7:35:55 GMT -5
One thing I don't understand is how much an amp that costs a mere $999 can be examined and critiqued so hard to the point of some thinking it's a complete waste of their money yet the pair of monoblocks on the list for a staggering $188,000 don't get any criticism at all, like seriously $188,000 is almost as much as my house, well actually it would prob cost more than my home due to the fact I'm in Canada and that's a US price tag, I actually find that completely pathetic but hey that's the world we live in right. So does the XPA-2 actually sound like a transistor if you have the chance to listen to gear costing that much, I highly doubt it. Since my value of money is obviously wayyyyyy different than the guy spending $200,000 on amps I would think those amps sound like garbage considering their cost haha. I guess only the rich can truly get great sounding systems ?? Now, now - it will be ok..  |
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KeithL
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Post by KeithL on Oct 2, 2020 12:13:07 GMT -5
Which can fill a drinking glass better.... a garden hose, a fire hose, or a water tower?
(Hint.... unless you have an awfully big drinking glass, or need to fill it in under a microsecond, it really doesn't matter.)
That's why SMPS's have some capacitance, just nowhere near as much as torroids. It's part of that "implemented correctly" thing I mentioned.... It's like the difference between a hose and a water tower. |
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KeithL
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Post by KeithL on Oct 2, 2020 12:55:59 GMT -5
The vast majority of people have little to no understanding of what a transformer does and does not do.
Transformers operate by converting electrical energy into magnetic energy and then back again. Because of how they do so transformers generally pass alternating current but not direct current. (Transformers can pass varying DC signals, like "DC pulses", but not pure DC.)
Therefore, all transformers whose primary and secondary windings are isolated from each other isolate for DC. "Isolation transformers" do NOT magically "isolate against noise". They isolate against DC offsets and such by virtue of the fact that, because of the technology they use, they don't pass DC. Likewise, certain specific types of noise, which are generally described as "common mode noise", also fail to be passed.
However other types of noise will pass through a transformer quite readily. The main reason "isolation transformers" tend to block noise is simply that they are optimized to pass 60 Hz (which is the line frequency).
(Because of their typically high inductance they work poorly for transmitting noise... which happens to be a benefit in this case.) (The reason the output transformers in tube amps cause distortion is that it is actually difficult to design a true wide band transformer.)
Incidentally, most SMPS do include a transformer, and many of them are in fact isolated... including ours. (And many low cost line operated 60 Hz power supplies are not... or were not before the current safety laws were passed.)
The trick is that the practical size of a transformer is limited by the frequency it is designed to work with.
In order to operate at 60 Hz a power transformer must be big and heavy. In general, for any given amount of power, as the frequency goes up, the required size for the transformer goes down. The power transformer in our XPA amps, good for almost 3,000 watts, is that square block with the yellow tape around it. Compared to an old-style 60 Hz power transformer, it operates at a much higher frequency, so it can be much smaller.
The main reason why 60 Hz power supplies need those great big capacitors is this... Those capacitors may in fact store quite a bit of charge... But they have to because they can only be refilled 120 times a second. A SMPS works with much smaller capacitors because it has the opportunity to refill them a lot more often.
A lot of you are also missing the most important part of the deal...
With a standard transformer-based linear power supply the power is dumped into those capacitors by the rectifiers... And that power is dumped into the capacitors in pulses... (Picture a bunch of guys with buckets filling up a water tank.) The capacitors then smooth out those pulses into steady DC power by providing a storage reservoir... However, as the amplifier draws more power, the output voltage sags down, and the noise goes up... (That's one reason why those capacitors have to be so big... and why bigger ones sometimes work better.)
A SMPS WORKS VERY DIFFERENTLY. Virtually all SMPS are REGULATED - including ours.
This means that we don't have to hope that the reservoir will be big enough to smooth out most of the noise. We have active circuitry that carefully monitors the level and meters the refills to ensure that the output remains constant. So, when you design a SMPS, you do have to be careful to ensure that all of the high frequency noise is removed.... But you DON'T have to worry about the voltage sagging under load... Or about the 60 Hz or 120 Hz line noise increasing under heavy load...
Because they are actively eliminated...
If you think of an old style power supply as a big reservoir that more or less maintains a steady output voltage... Then the output of an SMPS is more like the output of a DC amplifier that is amplifying the output voltage of a precision battery... (The technology has become so common that people no longer bother to explain how elegant it really is...)
It doesn't "break the link" since it doesn't draw on the capacitance every time, that's only for when needed by the source material, not the power company. Powerline noise doesn't get filtered by the power supply capacitors; if it did the amp wouldn't be susceptible to brown outs and all other issues that torroids and their capacitors do nothing to prevent. However none of this matters as it's just classic audiophools doing armchair engineering. The only thing that matters is the end result and how does it sound. If it doesn't sound better then other amps, then people won't buy it, however clearly these are fine sounding amps. Fist by definition isolation transformers isolate. Second capacitors store charge (you know, those little invisible particles called electrons). The amount of storage is small but more than enough to supply up to four times the instantaneous power of a direct line and more than enough to obscure (o.K. filter) many small line disturbances. SMPS introduce high frequency noise (a lot). but they are cheap cheap cheap and that is their attraction. If you want to protect against brown outs, you need a lot more storage, not less. You need an uninterruptable power supple with battery storage. |
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Post by KeithL on Oct 2, 2020 13:11:53 GMT -5
In the real world nothing is perfect....
Those switch positions determine which end or part of the secondary winding is connected to ground. In theory a transformer wouldn't need to be grounded at all. However that could raise safety issues if they were connected - or mis-connected - in certain ways. Also, because nothing, including a transformer, is perfect, the theory is not absolute. For example, there is capacitance between each winding and the core, and between the two windings. There are also things like winding resistance, and insulation leakage, and core hysteresis.
As a result of all these imperfections certain configurations work better in certain situations.
The "isolated" setting probably really does leave the transformer secondary winding isolated from ground. In this case "where ground sits" will be determined by how the devices you have plugged into that transformer are grounded.
The "balanced" setting ties a center tap on the secondary winding to ground. As a result, the two output wires carry a "balanced signal"
(the power voltage on them is always "equal and out of phase relative to ground"). This may put less strain on the insulation on some devices... But some devices may specifically NOT like to be connected that way... And, possibly more importantly, depending on what you have connected, one setting may be quieter than the other...
Yep.....MAC is famous for use of autoformers. And I just remembered one other thing. The ISO in my power conditioner has some kind of ground switch. The 2 postions are marked 'Balanced' and 'Isolated'......Any clarification? And yes, I take your point. ALL are isolation. But the one of particular interest to audio types would be the 1:1 type. I saw a power conditioner at a show years ago, which at the core, was a BIG transformer. Maybe 2kva or better. Weighted a LOT. I don't remember what else was in it.... I think it may have started with a medical grade Plitron. I worked with plenty of engineers over the years. And a few PhD types. One started in Chemistry but ended up in Semiconductors about which he knew a LOT. I'd go visit him at his desk about 2x monthly for 6 to 10 minutes of him telling me about anything to do with our process and product. Sometimes I'd start with a specific question. Maybe about Implant or some diffusion process. In the motor and control industry, I'll bet you used stuff made in my fab. IRC made LOTS of this kind of thing including very high current modules all th way down to FRED or IGBT devices. All made on the same line. |
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Post by KeithL on Oct 2, 2020 13:16:08 GMT -5
I still recall when they reviewed a certain pair of monoblocks... at a mere $85k for the pair... And one of the review pair actually burned out during its "preconditioning warm-up"... Of course the manufacturer supplied a replacement... (But, oddly, nobody suggested that "burning out" would disqualify it from being a great deal either.)
One thing I don't understand is how much an amp that costs a mere $999 can be examined and critiqued so hard to the point of some thinking it's a complete waste of their money yet the pair of monoblocks on the list for a staggering $188,000 don't get any criticism at all, like seriously $188,000 is almost as much as my house, well actually it would prob cost more than my home due to the fact I'm in Canada and that's a US price tag, I actually find that completely pathetic but hey that's the world we live in right. So does the XPA-2 actually sound like a transistor if you have the chance to listen to gear costing that much, I highly doubt it. Since my value of money is obviously wayyyyyy different than the guy spending $200,000 on amps I would think those amps sound like garbage considering their cost haha. I guess only the rich can truly get great sounding systems ?? Now, now - it will be ok.. |
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Post by bradleyaudio on Oct 2, 2020 15:13:26 GMT -5
Yep.....MAC is famous for use of autoformers. To my knowledge(happy to be corrected if wrong) Mac used autoformers only in the output stages of most (not all) of their solid state amps, and never in the power supplies. |
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Post by mgbpuff on Oct 2, 2020 16:08:55 GMT -5
The vast majority of people have little to no understanding of what a transformer does and does not do.
Transformers operate by converting electrical energy into magnetic energy and then back again. Because of how they do so transformers generally pass alternating current but not direct current. (Transformers can pass varying DC signals, like "DC pulses", but not pure DC.)
Therefore, all transformers whose primary and secondary windings are isolated from each other isolate for DC. "Isolation transformers" do NOT magically "isolate against noise". They isolate against DC offsets and such by virtue of the fact that, because of the technology they use, they don't pass DC. Likewise, certain specific types of noise, which are generally described as "common mode noise", also fail to be passed.
However other types of noise will pass through a transformer quite readily. The main reason "isolation transformers" tend to block noise is simply that they are optimized to pass 60 Hz (which is the line frequency).
(Because of their typically high inductance they work poorly for transmitting noise... which happens to be a benefit in this case.) (The reason the output transformers in tube amps cause distortion is that it is actually difficult to design a true wide band transformer.)
Incidentally, most SMPS do include a transformer, and many of them are in fact isolated... including ours. (And many low cost line operated 60 Hz power supplies are not... or were not before the current safety laws were passed.)
The trick is that the practical size of a transformer is limited by the frequency it is designed to work with.
In order to operate at 60 Hz a power transformer must be big and heavy. In general, for any given amount of power, as the frequency goes up, the required size for the transformer goes down. The power transformer in our XPA amps, good for almost 3,000 watts, is that square block with the yellow tape around it. Compared to an old-style 60 Hz power transformer, it operates at a much higher frequency, so it can be much smaller. The main reason why 60 Hz power supplies need those great big capacitors is this... Those capacitors may in fact store quite a bit of charge... But they have to because they can only be refilled 120 times a second. A SMPS works with much smaller capacitors because it has the opportunity to refill them a lot more often.
A lot of you are also missing the most important part of the deal...
With a standard transformer-based linear power supply the power is dumped into those capacitors by the rectifiers... And that power is dumped into the capacitors in pulses... (Picture a bunch of guys with buckets filling up a water tank.) The capacitors then smooth out those pulses into steady DC power by providing a storage reservoir... However, as the amplifier draws more power, the output voltage sags down, and the noise goes up... (That's one reason why those capacitors have to be so big... and why bigger ones sometimes work better.) A SMPS WORKS VERY DIFFERENTLY. Virtually all SMPS are REGULATED - including ours.
This means that we don't have to hope that the reservoir will be big enough to smooth out most of the noise. We have active circuitry that carefully monitors the level and meters the refills to ensure that the output remains constant. So, when you design a SMPS, you do have to be careful to ensure that all of the high frequency noise is removed.... But you DON'T have to worry about the voltage sagging under load... Or about the 60 Hz or 120 Hz line noise increasing under heavy load...
Because they are actively eliminated...
If you think of an old style power supply as a big reservoir that more or less maintains a steady output voltage... Then the output of an SMPS is more like the output of a DC amplifier that is amplifying the output voltage of a precision battery... (The technology has become so common that people no longer bother to explain how elegant it really is...) Fist by definition isolation transformers isolate. Second capacitors store charge (you know, those little invisible particles called electrons). The amount of storage is small but more than enough to supply up to four times the instantaneous power of a direct line and more than enough to obscure (o.K. filter) many small line disturbances. SMPS introduce high frequency noise (a lot). but they are cheap cheap cheap and that is their attraction. If you want to protect against brown outs, you need a lot more storage, not less. You need an uninterruptable power supple with battery storage. A few points. 1)Line isolation transformers(50 or 60 hz designed) do in fact because of their bandwidth limitations remove or reduce the effect of line disturbances. 2) Large power supplies with large caps store energy in excess of the rate of flow of energy from the power line and this energy can be used to supply large instantaneous dynamic power requirements. 3)SMPS chops up the line sans a transformer and reassembles it into high frequency and the following isolation transformer is much smaller due to the high frequency / iron rule (that's why aircraft use 400hz as a standard to reduce weight), However the line power comes on to a circuit board with no limit to fault energy which a transformer supplies. This therefore is a danger. 4) SMPS needs no large caps because the output is regulated so that the output never sags. However there is a linear time lag from output to input to correction action so that the regulation is not fast enough to sustain an instantaneous pulse demand. 5)The energy in a large cap is setting there ready to use at all times - no time lag. |
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KeithL
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Post by KeithL on Oct 2, 2020 16:11:39 GMT -5
That would be correct....
An "autoformer" (or "autotransformer") is not some sort of special and wondrous thing.
What we're talking about is an inductor... which is a coil of wire... often with a ferromagnetic core (but not always). A device with a single winding, with only a connection at each end, is "an inductor". A device with two or more windings, isolated from each other, is a "transformer". A device with a single winding, but more than two connections on that winding, is an "autoformer" (or "autotransformer"). An autoformer is essentially a cheaper way to make a transformer if you don't need isolation between the windings. (There are really no major benefits to doing it that way beyond its being easier to make.)
You really need isolation in the power supply between the AC line and the rest of the electronics. (That way you avoid things like the risk of getting electrocuted if you happen to touch a speaker terminal and a water pipe.) (You also avoid being sued and running afoul of local safety regulations.)
In "the good old days" many devices neglected to include isolation... This included those old tube TVs whose metal chassis, inside the nice wooden cabinet, was "hot"... And some modern devices, like electric drills and hair dryers, still manage without isolation... By virtue of good insulation that absolutely ensures you can't accidentally touch any of the "hot parts"... With solid state amps the power supply isolates the active circuitry from the line... So there is no need for an extra stage of isolation at the output...
McIntosh originally used autoformers mainly to provide impedance matching... This allowed them to deliver the same rated power into different speaker impedances... This was a big deal back when solid state devices themselves were rather limited... Back when 100 watts was "a powerful amplifier" you needed to be able to deliver all of it into whatever speakers you had. The autoformers also help to minimize the risk to your speakers in the event of output device failure. (The downside is that they're big, heavy, expensive, and cause both distortion and phase shift....)
There is also a precedent by virtue of the fact that almost all tube gear requires output transformers. And, back in those days, the output transformers in a lot of McIntosh TUBE gear really were quite innovative. (Look up something called "unity coupling"... which involves balanced transformers with both plate and cathode windings.)
So, when they started making solid state gear, practical considerations aside, those autoformers became a sort of trademark...
Yep.....MAC is famous for use of autoformers. To my knowledge(happy to be corrected if wrong) Mac used autoformers only in the output stages of most (not all) of their solid state amps, and never in the power supplies. |
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KeithL
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Post by KeithL on Oct 2, 2020 16:48:24 GMT -5
All quite true....
HOWEVER, your last point is leveraged against a fallacy....
And that fallacy is that there is some benefit to having a power supply that can deliver more current than what is required.
The amount of current that is required to drive a load depends on the load itself. So, for example, you may NEED a huge surge of current to crank a compressor, or start an arc welder... However, you will never need a huge surge of current to drive a loudspeaker.
An 8 Ohm loudspeaker, being driven to a level of 8 watts, will draw 1 amp of current. This is true regardless of whether the amplifier driving it is capable of delivering 2 amps or 2000 amps. And there is no benefit whatsoever in designing that amplifier to be able to deliver 2000 amps.
(At most, it might make sense to have a capacity of 4 amps, in case that speaker really dips to 2 Ohms...)
You've got to look at all of the math....
At 60 Hz you need that big capacitor to store a lot of power because the next fill-up is 1/120 of a second away. With a SMPS, running at 100 kHz, the next fill-up is only 1/100,000 of a second away. Therefore the power has much less time to become depleted.
There is also a second aspect of the math which I omitted for the sake of simplicity....
With a 50 VDC linear supply your reservoir capacitors are being refilled from a rectifier.
And the output voltage coming from that rectifier only goes a little bit above 50V during part of the power cycle. In contrast, with a 50V SMPS, the primary power reservoir typically operates at around 270 VDC. This means that the reservoir is always available to deliver more power whenever it is needed.
And, when it does so, it can deliver that power more quickly and more efficiently.
It is true that big reservoir capacitors can come in handy if the line voltage actually fails for a significant part of a second... But it's also worth mentioning that the amount of ENERGY stored in a capacitor rises as the SQUARE of the voltage. (So those "little high voltage capacitors" in a typical SMPS actually store quite a bit more power than you might think.)
The vast majority of people have little to no understanding of what a transformer does and does not do.
Transformers operate by converting electrical energy into magnetic energy and then back again. Because of how they do so transformers generally pass alternating current but not direct current. (Transformers can pass varying DC signals, like "DC pulses", but not pure DC.)
Therefore, all transformers whose primary and secondary windings are isolated from each other isolate for DC. "Isolation transformers" do NOT magically "isolate against noise". They isolate against DC offsets and such by virtue of the fact that, because of the technology they use, they don't pass DC. Likewise, certain specific types of noise, which are generally described as "common mode noise", also fail to be passed.
However other types of noise will pass through a transformer quite readily. The main reason "isolation transformers" tend to block noise is simply that they are optimized to pass 60 Hz (which is the line frequency).
(Because of their typically high inductance they work poorly for transmitting noise... which happens to be a benefit in this case.) (The reason the output transformers in tube amps cause distortion is that it is actually difficult to design a true wide band transformer.)
Incidentally, most SMPS do include a transformer, and many of them are in fact isolated... including ours. (And many low cost line operated 60 Hz power supplies are not... or were not before the current safety laws were passed.)
The trick is that the practical size of a transformer is limited by the frequency it is designed to work with.
In order to operate at 60 Hz a power transformer must be big and heavy. In general, for any given amount of power, as the frequency goes up, the required size for the transformer goes down. The power transformer in our XPA amps, good for almost 3,000 watts, is that square block with the yellow tape around it. Compared to an old-style 60 Hz power transformer, it operates at a much higher frequency, so it can be much smaller. The main reason why 60 Hz power supplies need those great big capacitors is this... Those capacitors may in fact store quite a bit of charge... But they have to because they can only be refilled 120 times a second. A SMPS works with much smaller capacitors because it has the opportunity to refill them a lot more often.
A lot of you are also missing the most important part of the deal...
With a standard transformer-based linear power supply the power is dumped into those capacitors by the rectifiers... And that power is dumped into the capacitors in pulses... (Picture a bunch of guys with buckets filling up a water tank.) The capacitors then smooth out those pulses into steady DC power by providing a storage reservoir... However, as the amplifier draws more power, the output voltage sags down, and the noise goes up... (That's one reason why those capacitors have to be so big... and why bigger ones sometimes work better.) A SMPS WORKS VERY DIFFERENTLY. Virtually all SMPS are REGULATED - including ours.
This means that we don't have to hope that the reservoir will be big enough to smooth out most of the noise. We have active circuitry that carefully monitors the level and meters the refills to ensure that the output remains constant. So, when you design a SMPS, you do have to be careful to ensure that all of the high frequency noise is removed.... But you DON'T have to worry about the voltage sagging under load... Or about the 60 Hz or 120 Hz line noise increasing under heavy load...
Because they are actively eliminated...
If you think of an old style power supply as a big reservoir that more or less maintains a steady output voltage... Then the output of an SMPS is more like the output of a DC amplifier that is amplifying the output voltage of a precision battery... (The technology has become so common that people no longer bother to explain how elegant it really is...) A few points. 1)Line isolation transformers(50 or 60 hz designed) do in fact because of their bandwidth limitations remove or reduce the effect of line disturbances. 2) Large power supplies with large caps store energy in excess of the rate of flow of energy from the power line and this energy can be used to supply large instantaneous dynamic power requirements. 3)SMPS chops up the line sans a transformer and reassembles it into high frequency and the following isolation transformer is much smaller due to the high frequency / iron rule (that's why aircraft use 400hz as a standard to reduce weight), However the line power comes on to a circuit board with no limit to fault energy which a transformer supplies. This therefore is a danger. 4) SMPS needs no large caps because the output is regulated so that the output never sags. However there is a linear time lag from output to input to correction action so that the regulation is not fast enough to sustain an instantaneous pulse demand. 5)The energy in a large cap is setting there ready to use at all times - no time lag. |
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Post by leonski on Oct 2, 2020 20:39:34 GMT -5
All quite true....
HOWEVER, your last point is leveraged against a fallacy....
And that fallacy is that there is some benefit to having a power supply that can deliver more current than what is required.
The amount of current that is required to drive a load depends on the load itself. So, for example, you may NEED a huge surge of current to crank a compressor, or start an arc welder... However, you will never need a huge surge of current to drive a loudspeaker.
An 8 Ohm loudspeaker, being driven to a level of 8 watts, will draw 1 amp of current. This is true regardless of whether the amplifier driving it is capable of delivering 2 amps or 2000 amps. And there is no benefit whatsoever in designing that amplifier to be able to deliver 2000 amps.
(At most, it might make sense to have a capacity of 4 amps, in case that speaker really dips to 2 Ohms...)
You've got to look at all of the math....
At 60 Hz you need that big capacitor to store a lot of power because the next fill-up is 1/120 of a second away. With a SMPS, running at 100 kHz, the next fill-up is only 1/100,000 of a second away. Therefore the power has much less time to become depleted.
There is also a second aspect of the math which I omitted for the sake of simplicity....
With a 50 VDC linear supply your reservoir capacitors are being refilled from a rectifier.
And the output voltage coming from that rectifier only goes a little bit above 50V during part of the power cycle. In contrast, with a 50V SMPS, the primary power reservoir typically operates at around 270 VDC. This means that the reservoir is always available to deliver more power whenever it is needed.
And, when it does so, it can deliver that power more quickly and more efficiently.
It is true that big reservoir capacitors can come in handy if the line voltage actually fails for a significant part of a second... But it's also worth mentioning that the amount of ENERGY stored in a capacitor rises as the SQUARE of the voltage. (So those "little high voltage capacitors" in a typical SMPS actually store quite a bit more power than you might think.)
A few points. 1)Line isolation transformers(50 or 60 hz designed) do in fact because of their bandwidth limitations remove or reduce the effect of line disturbances. 2) Large power supplies with large caps store energy in excess of the rate of flow of energy from the power line and this energy can be used to supply large instantaneous dynamic power requirements. 3)SMPS chops up the line sans a transformer and reassembles it into high frequency and the following isolation transformer is much smaller due to the high frequency / iron rule (that's why aircraft use 400hz as a standard to reduce weight), However the line power comes on to a circuit board with no limit to fault energy which a transformer supplies. This therefore is a danger. 4) SMPS needs no large caps because the output is regulated so that the output never sags. However there is a linear time lag from output to input to correction action so that the regulation is not fast enough to sustain an instantaneous pulse demand. 5)The energy in a large cap is setting there ready to use at all times - no time lag. thus turing the 'claim' of wacky high amerages into a 'Red Herring' bit of advertising. One othe thing: I've seen the calculations for power supplies and most importantly RIPPLE. Here is the link to the Elliot Sound Products paper on Linear design. It gets quite involved, but you can skim for the bullet points. sound-au.com/power-supplies.htmOne other minor point. Years ago NAD advertised 'high headroom' amplifiers. They were 6db headroom which is 4x the RMS power. And I'd like to ask a question. IF it is so hard to design an output transformer with good wide bandwidth, how does that effect a PS transformer? It would seem that the same physics apply and the frequency response of this device would be BEST at the designed frequency, be that 50hz or 60hz.....for most users. So what happens to HF hash coming down the line? Say you're unfortunate enough to live near an AM radio station at 640khz or an FM station around 100mhz? What than? I've had RF apparently couple thru my SPEAKER wires! It was a bad deal to rid myself of that.....I wish I'd known about ferrite and such... |
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Post by rbk123 on Oct 5, 2020 12:02:01 GMT -5
I think possibly one of if not the most ridiculous things here on the lounge is that every thread that has an even minor mention to do with the Gen 3 amps it turns into a heated discussion on their power supply, talk about beating the dead horse with a dead horse, it seems some need to move on already, I've heard one and it sounded great as did the Gen 1 & 2 before it. Hey Chad - it only took 3 posts for a non-Gen 3 thread to devolve into a power supply debate. Looks like you were partially right: it's not a dead horse, that's not big enough - it's more of a stable with dead horses.  emotivalounge.proboards.com/thread/57753/emotiva-make-xpr-line-again |
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Post by Deleted on Oct 5, 2020 12:36:10 GMT -5
Does anyone actually want to address the 'harsh transistor' like sound described by reviewers? Other reviewers also have chimed in with 'masculine'.
I realize the amp is comprised of more than one part but operates as a system in a system. Having said that, I moved away from both the XPA Gen 3 to the DR series only to feel they lacked the desirable fidelity. I wasn't bout to search or hunt down out of warranty old gear as I wasn't attached to Emotiva branding.
My current amp has a permanent place in my system. If I am understanding correct Keith used 1 amp for all that is necessary for 8 watts into an 8 ohm speaker and another passed excess off as marketing for high current Amps. The Parasound Halo A31 passes 60+ Amps per channel. The mid bass range blossomed when compared to Emotiva. Mind you the ohm load for my speakers dives to 2.3 ohms in the mid bass region. I'm confused as to why if all the math shows one thing the overall fidelity says another.
Okay, I'm ready to be confronted by the Borg. Assisimilate me if you will. I'm ready to loose my artsy side for harsh, masculine, transistor like expression!
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Post by tropicallutefisk on Oct 5, 2020 12:56:16 GMT -5
Shimei, I have three DR1s and have not found any of them to have a harsh or "transistor" like sound. I will say they were a little brighter than my previous amps, but with a 0.5 ohm resistor added to my Maggies that brightness mellowed out and the highs are now smooth and velvety, not a hint of harshness. Easily the most pleasing highs I've had in my home. Not all amps work with all speakers, so I wonder if there is an issue in compatibility. I had a McIntosh that sounded mushy and dull on my Maggies. Now I would never say McIntosh makes weak, lackluster amps. I've heard several and loved the sound. Unfortunately, this particular amp just didn't mesh well in my system.
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Post by rbk123 on Oct 5, 2020 13:10:56 GMT -5
It's all relative. "Transistor" like compared to what other amps? Plus it's also about synergy - might have a certain sound with one speaker but different with another; certain sound with one pre-amp but different with another. Then in what room? Something so subjective as "transistor" like, is just far too subjective and too dependent on certain reviewers ears. Keep in mind no other reviewer has said that; other things, just not that.
There's only one way to be certain and you already know that.
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Post by creimes on Oct 5, 2020 13:15:17 GMT -5
Does anyone actually want to address the 'harsh transistor' like sound described by reviewers? Other reviewers also have chimed in with 'masculine'. I realize the amp is comprised of more than one part but operates as a system in a system. Having said that, I moved away from both the XPA Gen 3 to the DR series only to feel they lacked the desirable fidelity. I wasn't bout to search or hunt down out of warranty old gear as I wasn't attached to Emotiva branding. My current amp has a permanent place in my system. If I am understanding correct Keith used 1 amp for all that is necessary for 8 watts into an 8 ohm speaker and another passed excess off as marketing for high current Amps. The Parasound Halo A31 passes 60+ Amps per channel. The mid bass range blossomed when compared to Emotiva. Mind you the ohm load for my speakers dives to 2.3 ohms in the mid bass region. I'm confused as to why if all the math shows one thing the overall fidelity says another. Okay, I'm ready to be confronted by the Borg. Assisimilate me if you will. I'm ready to loose my artsy side for harsh, masculine, transistor like expression! I have always liked the sound of my Emotiva stuff, but I am not in the income bracket to try out most of the other stuff out there, heck even the new Gen 3 stuff is out of my reach because of increase in cost and our exchange rate, between the Gen 3 XPA-7 cost to me to my door is in the $3200 to $3400 range and my Outlaw 7000X cost was almost $1500, so less than half as much and why I choose the Outlaw amp over the Emotiva amp and the Outlaw 7000x amp is a really nice amplifier. I wouldn't even want to know what Parasound, McIntosh or even the Canadian brand Bryston would cost me but I'm sure it would be more than what our one and only car we have is worth haha, so like I've mentioned before yet i don't believe it's true that only the rich can afford good SQ ?? as I'm very very happy with my system. Chad |
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Post by Deleted on Oct 5, 2020 13:21:15 GMT -5
It's all relative. "Transistor" like compared to what other amps? Plus it's also about synergy - might have a certain sound with one speaker but different with another; certain sound with one pre-amp but different with another. Then in what room? Something so subjective as "transistor" like, is just far too subjective and too dependent on certain reviewers ears. Keep in mind no other reviewer has said that; other things, just not that. There's only one way to be certain and you already know that. If it's all relative then having only a single point of reference becomes the standard. Given the price of my speakers and the reviews they received I thought no way this is as good as the reviewers claimed. That began the switching out of upstream components mainly the amp. I've heard high end fidelity and I've listened to various stringed instruments as reference. I tend to lean that way for reference. Just curious are we to respond to negative reviews describing Emotiva products as being subjective, opinionated, and/or lacking any truth? Is that the tactic to fill pages w/ technical jargon explaining away why on paper this electronic is better than the other? I've come across an ideology and philosophy now and then that weren't realistic. I imagine math is like that too. Physics for example showing how a hoard of elephants may balance on the tip of a pin. Of course, there's the problem of me having the same opinion derived by listening experience as other reviewers state in description. For the price point Emotiva is a great amp showing lots of value for the dollar. Just wondering what Emotiva could offer for a slightly higher price point? Seems some in this thread believe there is a market. I mean obviously, the Stereophile list went upwards and in excess of 6 figures for amps. |
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