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Post by rclark on Mar 25, 2011 20:44:14 GMT -5
Other than improved functionality, do we expect any sq improvements over an xda by itself? And if so, why?
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Post by rocky500 on Mar 25, 2011 23:31:07 GMT -5
I am only guessing here
I think the whole purpose of the XSP is the extra functionality.
I would think SQ would be at least as good as the XDA.
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Post by rclark on Mar 26, 2011 3:05:35 GMT -5
Is it possible to expand upon that? We have other threads talking about xsp noise floors and soundstages and stuff like that.
I'm led to believe that a preamp is supposed to be neutral but I'm also led to believe that a preamp can improve the level of SQ of a system.
So can we conclude that the XSP would neither improve nor detract from the SQ of the XDA, but, for example, the USP would detract from the SQ of the XDA?
What I'm trying to understand is: will it be identical SQ when straight from XDA or from XDA -> XSP, or is it possible that the XSP could improve the sq even further somehow?
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Post by Poodleluvr on Mar 26, 2011 12:38:15 GMT -5
"Benchmark DAC1 Pre USB D/A headphone amplifier" "By Sam Tellig • Posted: Dec 28, 2008 • Published: Oct 9, 2008" www.stereophile.com/digitalprocessors/1008bench/index.html"As for the analog output stage, it was fine, and showed that op-amps have become very respectable indeed. But get real—don't expect the Benchmark DAC1 Pre to trounce a really great dedicated line stage, such as the Parasound Halo JC2 or Conrad-Johnson CT5, both of which I had on hand for comparison. In terms of dynamic shadings, tonal color, and, of course, control flexibility, a great dedicated line-stage preamp is likely to win out. The wonder is that the Benchmark came so remarkably close." |
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Post by GMan on Mar 26, 2011 13:45:15 GMT -5
Is it possible to expand upon that? We have other threads talking about xsp noise floors and soundstages and stuff like that. I'm led to believe that a preamp is supposed to be neutral but I'm also led to believe that a preamp can improve the level of SQ of a system. So can we conclude that the XSP would neither improve nor detract from the SQ of the XDA, but, for example, the USP would detract from the SQ of the XDA? What I'm trying to understand is: will it be identical SQ when straight from XDA or from XDA -> XSP, or is it possible that the XSP could improve the sq even further somehow? Logic says that for the cleanest, purest sound, the shortest signal path is the best. Having said that, the XDA-1 has no bass management, so if you need it, you need the XSP-1 or some other device to perform bass management. |
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Post by rclark on Mar 27, 2011 0:05:10 GMT -5
So I can take from that article that adding an xsp to the xda may yield some improvements rather than having no effect.
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Post by thielguy on Mar 27, 2011 18:13:26 GMT -5
i've gotten it from emo support that the xda is the best approach for my 2 channel system with no subwoofer, and no analog (phone) input needed. This is without have tried either yet, let alone done an A / B, but you figure the emo-dudes would be in the know!  |
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Post by jasonf on Mar 28, 2011 11:54:40 GMT -5
Is it possible to expand upon that? We have other threads talking about xsp noise floors and soundstages and stuff like that. I'm led to believe that a preamp is supposed to be neutral but I'm also led to believe that a preamp can improve the level of SQ of a system. So can we conclude that the XSP would neither improve nor detract from the SQ of the XDA, but, for example, the USP would detract from the SQ of the XDA? What I'm trying to understand is: will it be identical SQ when straight from XDA or from XDA -> XSP, or is it possible that the XSP could improve the sq even further somehow? Logic says that for the cleanest, purest sound, the shortest signal path is the best. Having said that, the XDA-1 has no bass management, so if you need it, you need the XSP-1 or some other device to perform bass management. The XDA also only has digital volume control, so at some point you're going to end up trimming bits if you turn the volume down far enough. |
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Post by jasonf on Mar 28, 2011 11:57:14 GMT -5
"Benchmark DAC1 Pre USB D/A headphone amplifier" "By Sam Tellig • Posted: Dec 28, 2008 • Published: Oct 9, 2008" www.stereophile.com/digitalprocessors/1008bench/index.html"As for the analog output stage, it was fine, and showed that op-amps have become very respectable indeed. But get real—don't expect the Benchmark DAC1 Pre to trounce a really great dedicated line stage, such as the Parasound Halo JC2 or Conrad-Johnson CT5, both of which I had on hand for comparison. In terms of dynamic shadings, tonal color, and, of course, control flexibility, a great dedicated line-stage preamp is likely to win out. The wonder is that the Benchmark came so remarkably close." Can anyone explain to me the difference between an op-amp and a line stage? |
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DYohn
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Post by DYohn on Mar 28, 2011 12:13:03 GMT -5
Can anyone explain to me the difference between an op-amp and a line stage? An op-amp (operational amplifier) is an electronic device (a "chip") that is used inside most electronic gear to perform a number of specific functions. It is a component used in the design and construction of products and is a part that consumers generally do not concern themselves with. A "line-stage" is a signal amplifier that boosts the voltage of a line-level signal. It is often used in situations where the source produces too low an output level, or to overcome losses where long cable runs are necessary, or where the user desires changes to the signal character such as introducing tubes into the signal path. |
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Post by thielguy on Mar 28, 2011 19:03:46 GMT -5
The XDA also only has digital volume control, so at some point you're going to end up trimming bits if you turn the volume down far enough. Jason, or others: I'm not sure I understand this... I do listen at somewhat lower than average volumes (I think) and this concept is new to me. Could you explain it a bit please? |
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Post by maxpower47 on Mar 29, 2011 11:32:47 GMT -5
The XDA also only has digital volume control, so at some point you're going to end up trimming bits if you turn the volume down far enough. Jason, or others: I'm not sure I understand this... I do listen at somewhat lower than average volumes (I think) and this concept is new to me. Could you explain it a bit please? As I understand it, that's not quite how it works. It is a digitally controlled analog volume control. In a pure digital volume control, the amplitude of the output is reduced by shifting all the bits in each sample to the right, dropping the least significant bits. This isn't as bad as it sounds because the information in those bits would be below the noise floor anyway, but you are losing information. In the XDA, it is a regular analog volume control (a resistor ladder I believe) whose level is set by a digital signal. So in the firmware there is a mapping of volume levels (0-80 in half step increments) to settings for the analog volume control. That's how they were able to change it from a linear to a logarithmic volume control with just a firmware update. There should be no difference between the quality of a volume control like this and a regular analog volume control physically connected to a knob on the front. |
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Post by jasonf on Mar 29, 2011 15:17:53 GMT -5
Can anyone explain to me the difference between an op-amp and a line stage? An op-amp (operational amplifier) is an electronic device (a "chip") that is used inside most electronic gear to perform a number of specific functions. It is a component used in the design and construction of products and is a part that consumers generally do not concern themselves with. A "line-stage" is a signal amplifier that boosts the voltage of a line-level signal. It is often used in situations where the source produces too low an output level, or to overcome losses where long cable runs are necessary, or where the user desires changes to the signal character such as introducing tubes into the signal path. I'm still not 100% clear Your description of a "line stage" matches that of what an op-amp does, increases the voltage. Not all op-amps are ICs either. So I still don't understand what makes a line stage different. Wikipedia has an entry for op-amps: en.wikipedia.org/wiki/Opamp |
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Post by roadrunner on Mar 29, 2011 15:57:13 GMT -5
maxpower47, you did an excellent job of explaining the XDA-1's volume control circuitry. Actually, this is one of cleanest ways to change the volume without adding any distortion in the process.
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DYohn
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Post by DYohn on Mar 29, 2011 17:16:15 GMT -5
An op-amp (operational amplifier) is an electronic device (a "chip") that is used inside most electronic gear to perform a number of specific functions. It is a component used in the design and construction of products and is a part that consumers generally do not concern themselves with. A "line-stage" is a signal amplifier that boosts the voltage of a line-level signal. It is often used in situations where the source produces too low an output level, or to overcome losses where long cable runs are necessary, or where the user desires changes to the signal character such as introducing tubes into the signal path. I'm still not 100% clear Your description of a "line stage" matches that of what an op-amp does, increases the voltage. Not all op-amps are ICs either. So I still don't understand what makes a line stage different. Wikipedia has an entry for op-amps: en.wikipedia.org/wiki/OpampNot all op-amps change the voltage. Some are logic gates, some are voltage dividers, some are simple switches... all solid-state "line stage amplifiers" will likely use an op amp or five. Almost every solid state product in the world uses op-amps of one sort or another. They are not something you go out and purchase for your system unless you are soldering some project together and in that case you wouldn't ask this question. A line-stage is a product that CAN go out and purchase and plug into your system. And yes, all op-amps these days are ICs, although there may still be some archaic product around that still employs tubes, but that would be the exception not the rule. |
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Post by jasonf on Mar 29, 2011 17:53:07 GMT -5
Ok, so a an op-amp is a building block that is used in different electronics including line stages.
I was confused by the Stereophile review above because it seemed to be pitting opamps against line stages.
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DYohn
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Post by DYohn on Mar 29, 2011 17:57:34 GMT -5
Ok, so a an op-amp is a building block that is used in different electronics including line stages. . That is exactly right. I don't know what Stereophile might have been doing, but perhaps they were mis-using the term...? |
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