Although I know the so called "objective data" I would love to know about the ton of subjective data about a "wire with gain" amplifier.
Constant Power
- Thread starter mep
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Although I know the so called "objective data" I would love to know about the ton of subjective data about a "wire with gain" amplifier.
Mep,
But it was the normal thing - the ARC has a much higher output impedance than the Krell, and the active speaker probably had an high impedance in the bass, as there was no speaker load in those frequencies. This means that the relative level applied to the bass crossover was higher than with the Krell.
Sometimes Ohm's law plays some nasty tricks.
I hope FrantzM is watching and approves my post.
Mep,
But it was the normal thing - the ARC has a much higher output impedance than the Krell, and the active speaker probably had an high impedance in the bass, as there was no speaker load in those frequencies. This means that the relative level applied to the bass crossover was higher than with the Krell.
Sometimes Ohm's law plays some nasty tricks.
I hope FrantzM is watching and approves my post.
Fransisco-I know you are correct that the VS115 output impedance is higher than the KSA-250, but I have no idea with respect to the impedance of the active 14" driver in the BP7000SC.
If the driver is active the load should be value of a dummy resistor and/or coil just to avoid having no DC path and a high variation in the impedance curve. But it should be high to avoid asking current from the amplifier in the bass - otherwise you loose one of the advantages of the active bass.
Mep,
But it was the normal thing - the ARC has a much higher output impedance than the Krell, and the active speaker probably had an high impedance in the bass, as there was no speaker load in those frequencies. This means that the relative level applied to the bass crossover was higher than with the Krell.
Sometimes Ohm's law plays some nasty tricks.
I hope FrantzM is watching and approves my post.
I concur
Here is the “thing”: I’m sure that the Atma-Sphere amps when used with speakers that have complimentary impedance curves (two wrongs make a right?) will sound good. I think what some people take exception to is the attitude that only Atma-Sphere amps get it “right” and all other amps be they SS or tube amps with transformers are “wrong” if they use negative feedback. Pack that onto the statement that any speaker that won’t sing with the Atma-Sphere amps (or amps that don’t use any negative feedback) are speakers that will never sound like “real” music.
And then you couple the above beliefs with the thought process that has been stated and/or implied that people who don’t “get” what Ralph is saying and believe what he is saying is true are stuck in a false paradigm. If we want to have an amplifier that sounds like “real” music, we all need to have Class A OTL amps that use triodes, no negative feedback, lots of second harmonic distortion, very low dampening factor, and have a high output impedance (although Ralph likes to refer to his output impedance as “moderate”). That is a lot of Kool-Aid to swallow.
I will be at RMAF in October and I plan on visiting every room that is using Atma-Sphere amps so I can hear the amps with different speakers and form my own opinions. It will be interesting to see what speakers are going to be used with Atma-Sphere amps.
And then you couple the above beliefs with the thought process that has been stated and/or implied that people who don’t “get” what Ralph is saying and believe what he is saying is true are stuck in a false paradigm. If we want to have an amplifier that sounds like “real” music, we all need to have Class A OTL amps that use triodes, no negative feedback, lots of second harmonic distortion, very low dampening factor, and have a high output impedance (although Ralph likes to refer to his output impedance as “moderate”). That is a lot of Kool-Aid to swallow.
I will be at RMAF in October and I plan on visiting every room that is using Atma-Sphere amps so I can hear the amps with different speakers and form my own opinions. It will be interesting to see what speakers are going to be used with Atma-Sphere amps.
I sure hope so - I'm pretty heavily invested in the idea that amp/speaker/room forms a "system within a system", the more complimentary the better.
Okay, just please don't take it as a personal affront that Ralph honestly believes in what he's doing, and isn't afraid to stick his neck out accordingly.
I guess the only way for you to find out whether there is any merit to Ralph's approach would be to go to RMAF and visit every room with Ralph's amps so you can hear them on different speakers and form your own opinion. I know that's a lot to ask. If you decide to do it, I very much look forward to meeting you. I'll be using Ralph's amps in Room 1100, please introduce yourself.
Sweet!
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My understanding is that the subwoofer amp is getting its signal from the amplifier's output voltage. The input impedance of the subwoofer amp is probably in the thousands of ohms (so it sees very little current and therefore very little wattage), possibly in parallel with a passively-driven woofer or woofers in the Def Tech speaker, and possibly in parallel with a passive high-pass filter.
The Krell is a constant-voltage amp, while the voltage that the Audio Research amp puts out varies somewhat with the load. The AR amp is putting out a bit higher voltage into the speaker's impedance peaks, and if there's an impedance peak and/or rise in the bass region (perhaps due to a highpass filter - I really don't know the details of what Def Tech is doing), then the voltage input into the subwoofer amp is modified accordingly, and would probably be higher than its output into an 8-ohm load. That would be my guess as to why the Def Tech had more bass with the AR amp than with the Krell.
When using a power paradigm amp/speaker combination with a subwoofer system, I've opted for line-level rather than speaker-level inputs for the subwoofer amp. Imo that's the better tool for that job in that situation.
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One designer's goal may be to deliver to the listener's ears, as accurately as possible, the exact waveforms that are on the recording, no more and no less.
A second designer's goal may be to replicate, as closely as possible, the perception of listening to a live performance.
Which is correct?
Or, are they both the same, just expressed differently? Intuition and common sense tell us that they are indeed one and the same goal, but in this case intuition and common sense mislead us.
Consider in-room reflections. Good or bad? The first designer would say such reflections are bad, because they are not a part of the recording and therefore are, by definition, unwanted noise and/or distortion. This view makes sense.
The second designer would say reflections are good (if done right), because they enhance the subjective realism of the listening experience. This view takes a very long time to explain, the reflections can't be too much this or too much that, and in the end it's a convoluted theory that utterly fails to have the elegant simplicity of the first. How can the second designer embrace room reflections and lay any claim to accuracy? And isn't accuracy what matters most?
So... what would Toole say? Whatever it is, it would probably take him a whole book to say it all.
I'm sure you can see by now that I'm using in-room reflections as an example of something highly counter-intuitive that ends up serving the goal of more realistic perception quite well.
The whole power paradigm approach is a bit like that in my opinion, although at present it has far fewer words in print to support it than does Toole's convoluted and highly counter-intuitive take on in-room reflections.
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What live performance? In what room? From what seat? With who's ears? From what recording?
This is why, in my other post, I referred to this whole issue as a variation of the old musical vs. accurate theme. When the designer's goal is to "replicate the perception of a live performance" or create musicality, or euphony, or warmth or an enveloping presence or whatever poetry of the day describes this approach to audio design, one thing is clear; the designer is endeavoring to broadly, systematically alter the art; all the art played on the system.
Unless we're talking about signal processing (and we're not) in which the alterations can be adjusted to individual rooms, tastes and recordings, and bi-passed altogether, this designer has left the field of audio reproduction and sat down behind the desk with every mastering engineer; he has created a "master," an alteration of the recording, that he believes makes the recording better. Correction: He believes it makes all recordings better, and applies his single re-mastering to everything from Bill Evans recorded live and solo in a single room on vintage tube mics and tape, to The Decemberists, meticulously layered and multi-tracked in zeros and ones.
There's nothing wrong with this if you like the way it sounds. I even have to admire the confidence required to believe so much in your hardwired EQ that you think it's good for everyone, every recording, every room. The problem is the purveyors of such equalization are rarely honest with themselves, much less the rest of us. That their child is beautiful in it's own way, if objectively inaccurate, doesn't seem to satisfy. Unable to say that their hardwired re-mastering of the recorded history of music is more accurate, they come up with something like it is "real music" not "good hifi."
Confidence becomes hubris. If you are serious digital/SS guy on a high-end forum you get this sort of thing all the time from the valve/vinyl crowd. You get used to it. Ralph came in and applied exactly the same argument, which goes something like "I don't have the data to back it up, in fact the data is not in my corner, but my approach is more like real music than yours," and he applied it very narrowly. He pushed most of the inner circle out into the cold and unmusical, and left a very small elite. The old elite won't suffer their banishment gladly.
Oh and by the way:
Applying exactly the same systematic, hard-wired, unalterable signal processing to everything from crude early Charlie Parker recordings to modern digital studio recordings, and expecting it to have the universal effect of bringing the listener closer to real music is not even rational, much less correct. You may love the way it sounds, but correct is certainly not a word I'd apply. I don't doubt this stuff can sound really good, I'd just like to see one of you admit, just once, that what you're doing is altering the recordings to taste, not bringing them closer to "real music," or some other euphemism for the signal integrity you cannot claim. And I think if all that energy and passion was going into developing great signal processing tools that could be adjusted to recordings and rooms, it would do a lot more good.
Tim
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Tim,
You want us to admit something we do not belief just for your pleasure?
You seem to forget we all listen using the same type of hears, until someone connects the bits directly to the brains, bypassing the headphones. If someone finds a way of systematically fooling our perceptual system making many people feel they are closer to the "real music" why should we deny it?
The receipt is not unique and universal - diversity it is a great aspect of high-end audio. We are just debating Ralph and Duke perspectives on this thread. We could have one for each high-end audio designer if they wanted to share their views at WBF.
And yes, my views addressed mainly acoustical music - my Klaus Schulze days are long gone.
There is a distinction in aiming for "sounds like the real thing as I have experienced" and trying to recreate "the event" wether actual or mixed. I don't believe anybody here is going for the very literal latter. We all know that is impossible.
This distinction is known since long. The objective of sound reproduction is not the physical recreation of the same exact conditions (the event), but the perceptual recreation of the experience associated with the event. There is however a connection between both - the reproduction of some physical aspects increases significantly the probability of the emotional recreation. Besides, some tricks in the recording and playback process can also increase the quality of the experience of sound reproduction. And also, some small errors in both processes manage to destroy it.
That was the Bose philosophy and I always found it to be flawed. The Bose way of achieving "the perception of listening to a live performance" was to bounce sound off the rear and side walls in order to get a mix of direct and reflected sound to match the arrival times of how you might possibly hear music in a live venue. One of the fatal flaws in that recipe is that it tends to homogenize all recordings played through those speakers (I'm talking Bose 901 speakers). The sonic thumbprint of the Bose 901 is way bigger than it should be and it distorts what the recording should/would sound like and lends a degree of sameness to every recording. They might sound sort of cool at first, but once you figure out what they are doing, they will wear on you very quickly.
In an earlier comment you made, you said something about being vested in the amp/speaker/room interface. I hope we all are.
Just because you find Bose implementation of the audiophile dream flawed does not mean all others are also flawed.
BTW1, I think that other listeners will weight differently the pro's and against's of Bose 901 - from the Stereophile review:
If we were to judge the 901 in terms of the best sound available, then, we would say that it produces a more realistic semblance of natural ambience than any other speaker system, but we would characterize it as unexceptional in all other respects. It is ideal for rock enthusiasts to whom sheer sonic impact is of paramount importance, and for classical listeners who want the next best thing to ambient stereo without the cost and the bother of rear-channel add-ons. However, we doubt that the 901 will appeal to perfectionists who have developed a taste for subtleties of detail and timbre.
BTW2 - I also am not an enthusiast of Bose 901's for my own listening. I can not forgive their small errors and I love to be considered a perfectionist.
Just because you find Bose implementation of the audiophile dream flawed does not mean all others are also flawed.
BTW1, I think that other listeners will weight differently the pro's and against's of Bose 901 - from the Stereophile review:
If we were to judge the 901 in terms of the best sound available, then, we would say that it produces a more realistic semblance of natural ambience than any other speaker system, but we would characterize it as unexceptional in all other respects. It is ideal for rock enthusiasts to whom sheer sonic impact is of paramount importance, and for classical listeners who want the next best thing to ambient stereo without the cost and the bother of rear-channel add-ons. However, we doubt that the 901 will appeal to perfectionists who have developed a taste for subtleties of detail and timbre.
BTW2 - I also am not an enthusiast of Bose 901's for my own listening. I can not forgive their small errors and I love to be considered a perfectionist.
Of course they would-people bought lots of them. It should be obvious by now that we all don't hear the same way, and we all don't value the same things in terms of SQ or lack thereof. Gear that some people will run from others will run to. And I for one never considered the errors of the Bose 901 to be small.
I thought the real goal of the high-end community was to make components as neutral as possible. And by that I mean the components are designed to get out of the way of the recording as much as possible by not adding or subtracting information. If you have a system that has one or more *homogenizers* in it, you may love the fact that every recording pretty much sounds like every other recording, while others will find it quite boring and know that something is wrong with the way the recordings sound. I would think that if you lived long-term with a component that generated lots of second harmonic distortion every time the power switch was flipped to "on" and music was playing through it that eventually you would recognize the added distortion and you would hear it with every recording you play. You could convince yourself that adding distortion to every recording you play makes them sound better, but I don't know how we could say this is a more accurate method of reproducing music.
Actually Tim- the argument is that negative feedback and odd orders STRIP music of real harmonics. What you claim as accuracy is actually the reverse. I also gave you a SS example to counter all your ranting about tubes and warmth etc. (btw, Ralph's amps don't sound warm or euphonic at all- ask anyone on this forum who has had an Atma demo- in fact many would say they are lean!).
Of course you refuse to read anything on the subject, then come preaching how all some people care about is loads of distortion and blankets of musicality. There is reading all over the web about this-- Crowhurst, Howard, Geddes, Cheever, Pass, Hayes, etc. Pass is the article I highlighted (because I think it's a well balanced paper) and from 2008, not 1958.
Should we all just go buy QSC amps with infinitessimal levels of THD, hundreds of dbs of negative feedback and call it a day? There is something else that needs to be measured and most of us on this forum agree that it sounds more like live unamplified instruments/sound.
How many people have done an unbiased comparison of such amps against the audiophile amps??? Hopefully I am not the only one
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