best amp for sierra-1nrt

[Beave]

Remember that 'beliefs' on this issue go both ways. But isn't it interesting to contemplate that just *one* instance of a person consistently being able to distinguish two well made preamps, or amps, or cables, or power cords, etc, in a double blind environment (in his own home with familiar music and equipment) give good reason to cast serious doubt on all those controlled studies in unfamiliar venues which supposedly showed otherwise.

Mark

It would be big news if it happened. And I'd be very interested to know about it, and, as an EE, to figure out what made the audible difference.

But so far, it hasn't happened. That's pretty telling, isn't it?

[markie]

It would be big news if it happened. And I'd be very interested to know about it, and, as an EE, to figure out what made the audible difference.

But so far, it hasn't happened. That's pretty telling, isn't it?

From what I remember (which may not be correct) there are three main factors that make cables different: impedance, capacitance, and inductance. There could be other factors at work as well that are outside the realm of electrical engineering.

I did a quick Google and found this from the Wall Street Journal:

Using two identical CD players, I tested a $2,000, eight-foot pair of Sigma Retro Gold cables from Monster Cable, which are as thick as your thumb, against 14-gauge, hardware-store speaker cable. Many audiophiles say they are equally good. I couldn't hear a difference and was a wee bit suspicious that anyone else could. But of the 39 people who took this test, 61% said they preferred the expensive cable.

That may not be much of a margin for two products with such drastically different prices, but I was struck by how the best-informed people at the show -- like John Atkinson and Michael Fremer of Stereophile Magazine -- easily picked the expensive cable.

Its sound was described as "richer," "crisper" and "more coherent." Like some wines, come to think of it.

In absolute terms, though, the differences weren't great. Mr. Atkinson guesstimated the expensive cables sounded roughly 5% better. Remember, by definition, an audiophile is one who will bear any burden, pay any price, to get even a tiny improvement in sound.

Now, it may not have been a rigorous DBT. But considering that the test was done in an unfamiliar room, with unfamiliar equipment (probably), and possibly unfamiliar music, the fact that at least two experienced listeners could easily tell the difference is telling. The results would have been far more pronounced in someone's familiar listening environment.

I myself went to an audio show a few years ago here in Toronto where a cable manufacturer (ONDA) was showing the differences among their own cables. The sound was coming beautifully through some Vanderstein 5As as I recall. Three difference cables, three different sounds, three different price brackets. They were clearly different, to me. However I was unsure which one I would prefer. One was 'sparkly', another gave a 'denser' sound, and the third seemed to highlight transients, it seemed more dynamic. And again, that was in an unfamiliar environment, with unfamiliar music. I'm not even an experienced listener, nor do I have exceptional hearing. So it's a no brainer to me that cables make a difference. And if *they* make a difference, I can perfectly understand that a preamp potentially would make an even bigger difference.

Mark

[Beave]

Cables, really? I should probably bow out of this before I get myself in trouble. Perhaps Jay has the ability to argue that one without offending. I do not have that ability.

[Dark Ranger]

Ah, the discussion of the audio cables. It brings us all closer together.

[petmotel]

Cables, really? I should probably bow out of this before I get myself in trouble. Perhaps Jay has the ability to argue that one without offending. I do not have that ability.

Nope, I'm done. I tried a couple of replies, I'd be banned for sure if I had posted.

Jay

[markie]

Ah, the discussion of the audio cables. It brings us all closer together.

Yes, yes, around a roaring fire. Marshmallow anyone?

In the bang for the buck proposition, cables are admittedly down near the bottom. At the top of the list, in no particular order, we have recording quality of the music, room treatments, speaker, and proper equalization/DSP room correction. For the next three down, in no particular order, we have preamp, source/dac, and amp. For the next three down, in no particular order, we have power cords, cables, and interconnects.

I shall refrain from mentioning more esoteric paraphernalia for the sake of forum harmony.

On this forum we can agree on one thing: Ascend speaker products present a very high value proposition for sure!

Mark

[davef]

Differences in dynamics are really just another way of saying some amps have more power capability than others, no? And if you aren't hitting near the limits of those power capabilities, then the dynamics should be equal.

Not really - it comes down to headroom reserve and this is where the amp's power supply capabilities really come into play. Transformer capacity and the amount of capacitance in the PS filter caps is key. I use an amp that has a full .250 farads (250,000 uF) of capacitance but yet is only 150 watts, and it has better dynamics then a 500 watt amp I also use... Wattage rating is an important aspect at determining dynamic capabilities, but it is absolutely not the only factor.... A good factor in determining dynamics is to compare the amp power ratings into different impedance loads. An amp that is rated at 100 watts into 8 ohms and 200 watts into 4 ohms, has plenty of current capability, while an amp that is rated at 100 watts into 8 ohms and 110 watts into 4 ohms has poor current capabilities.

True that not all amps measure flat. As I noted, tube amps often don't. But these days any properly-designed solid-state amp does. Oh, I'm sure you can find some ultra-expensive audiophile amp that doesn't measure flat, but that's due to either intent or incompetence.

And that is just it -- the designers intent... A 1-2 dB boost at the low end can make the amp sound warmer and more appealing, and the consumer would be left thinking, hey -- I can definitely hear a difference between amps, while being completely unaware that the amp is coloring the sound. This has happened to me on 2 occasions, and only after measuring the amps -- did I realize the cause...

After so many years in this industry, I have learned never to doubt what someone else hears. I may not agree with it and that person may not be hearing what they are due to the reasons they think -- but that is what makes this profession challenging for me -- trying to justify and quantify beyond reasonable doubt what someone else is hearing...

It is like speaker cables -- most say all speaker cable sounds the same, but I say speaker wire that is designed properly will sound the same. However, a cable can be wound in such a way such that it has high inductance, thus slightly rolling off the highs and making the sound warmer, meatier... This is the intent of the designer and it is, in my opinion, wrong to do so. But the cable will definitely sound different than an ordinary pair of speaker cables that does not have high inductance...

Does the consumer know he is purchasing high inductance speaker cables? Or a cable specifically designed to change the sound? No -- instead he is purchasing cable that is marketed as "sounding better"...

All cable should be sold with published specs such as these: http://www.mogamicable.com/category/...le/pure_sound/ Where capacitance, inductance and resistance is known...

During my M&K days, this was the only cable Ken wanted us using for testing and measurements, since the cable specifications were known and trusted.

[Beave]

Not really - it comes down to headroom reserve and this is where the amp's power supply capabilities really come into play. Transformer capacity and the amount of capacitance in the PS filter caps is key. I use an amp that has a full .250 farads (250,000 uF) of capacitance but yet is only 150 watts, and it has better dynamics then a 500 watt amp I also use... Wattage rating is an important aspect at determining dynamic capabilities, but it is absolutely not the only factor.... A good factor in determining dynamics is to compare the amp power ratings into different impedance loads. An amp that is rated at 100 watts into 8 ohms and 200 watts into 4 ohms, has plenty of current capability, while an amp that is rated at 100 watts into 8 ohms and 110 watts into 4 ohms has poor current capabilities.

True, but a little misleading. First, if the amp isn't clipping, which I stipulated earlier, then headroom reserve isn't helpful. If your amp is capable of putting out 100 watts per channel, continuous, and you're running it averaging 2 watts out and hitting 50 watts out at peaks, then headroom reserve never comes into play. Remember, I stipulated that the amp isn't clipping. By referring to an amp with higher transformer capacity and ps filter capacitance, you're basically describing an amp that can output more before clipping. So, yes, at extremes, the more capable amp will be more capable, but that's a syllogism.

As for the amps ratings example you gave, I know you're generalizing, but there are counterexamples on both sides. In other words, it's sort of a myth in audiophile circles. Consider 1) Some manufacturers, aware of this commonly-held belief in audiophile circles, purposely under-rate their output at 8 Ohms so that it looks like they double wattage into 4 Ohms, and 2) NAD, whose amps have considerable transformers and filter capacitance (at least compared to most AVRs), rates their amps for the same wattage at 8 Ohms and at 4 Ohms (continuous), yet they have impressive dynamic power output capabilities.

The overall point remains the same: An amp that isn't clipping shouldn't have a sound. Your description of headroom reserve is another way of saying dynamic power isn't the same as continuous power. True. Most amps can output more in short dynamic bursts, and some amps can output *way* more than their continuous output ratings. But if you're not using that capability, and most people aren't, then it's a moot point.

And that is just it -- the designers intent... A 1-2 dB boost at the low end can make the amp sound warmer and more appealing, and the consumer would be left thinking, hey -- I can definitely hear a difference between amps, while being completely unaware that the amp is coloring the sound. This has happened to me on 2 occasions, and only after measuring the amps -- did I realize the cause...

True, but how many amps these days are designed to have a boost? In all the measurements I've ever seen - on several websites, magazines, etc - I've never seen any that do.

Oh, sure, you can find an amp that is purposely designed to color the sound, but such an exception is easily measured and doesn't fall into the category of "properly designed and meeting spec." I had a former EE coworker who knew somebody who designed guitar amps. He was very well known and sought-out by rock guitarists for making amps with certain sound characteristics. His approach? Take a functioning amp (ie, flat FR, non-distorting, low noise) and purposely screw it up. And he was making good money doing so. But that's audio production, not reproduction, where the goal should be not to screw it up.

After so many years in this industry, I have learned never to doubt what someone else hears. I may not agree with it and that person may not be hearing what they are due to the reasons they think -- but that is what makes this profession challenging for me -- trying to justify and quantify beyond reasonable doubt what someone else is hearing...

After so many years in this industry as well, including having products reviewed in home theater mags, I've learned to always take what people say they hear with a huge grain of salt, because most people have no clue how easily our other senses, and who-knows-what-else-is-happening-in-our-brains, affects what we hear. I myself have been humbled by thinking I could easily pick out an amp over another, only to find myself completely guessing when I had to do it blind.

It is like speaker cables -- most say all speaker cable sounds the same, but I say speaker wire that is designed properly will sound the same. However, a cable can be wound in such a way such that it has high inductance, thus slightly rolling off the highs and making the sound warmer, meatier... This is the intent of the designer and it is, in my opinion, wrong to do so. But the cable will definitely sound different than an ordinary pair of speaker cables that does not have high inductance...

Does the consumer know he is purchasing high inductance speaker cables? Or a cable specifically designed to change the sound? No -- instead he is purchasing cable that is marketed as "sounding better"...

All cable should be sold with published specs such as these: http://www.mogamicable.com/category/...le/pure_sound/ Where capacitance, inductance and resistance is known...

During my M&K days, this was the only cable Ken wanted us using for testing and measurements, since the cable specifications were known and trusted.

It's pretty easy to "design" speaker cable that doesn't have high inductance or capacitance. In fact, the converse is true: It's pretty hard to "design" a speaker cable that doesn't have low inductance and capacitance. You have to screw it up on purpose, just like my coworker's friend who screwed up amp designs on purpose. Stick with simple, cheap copper wire of the appropriate gauge and no need to think any more about it.

[markie]

I just finished reading an excellent article at Audioholics, written less than a year ago. Guess what? The skeptics there, who had held that there are no audible difference between non clipping amps, are converting. It is well worth reading in its entirety.

http://www.audioholics.com/audio-amp...f-an-amplifier

I found much that was interesting. One is that clipping can occur even at normative listening levels, and we probably don't recognize it as clipping, just as inferior sound. Surprise!

Another thing I found interesting was that certain *agreed upon* sound characteristics of amplifiers such as veiled / transparent have no known correlation to electrical parameters that are known to electrical engineers. It is still rather much a mystery, although a very real phenomenon. This doesn't surprise me. For instance an EE sees a cable and he says it conducts electricity. A quantum physicist looking at the same cable will say it is a particular type of metal lattice that is propagating electrical waveforms that carry information. A bit of a difference in outlook!

Yet another tidbit from the article was that amp performance is very much related to what it is connected to. An amp may be quite good in one setup and not in another.

And that is why I think it is important to know what amps and other equipment are known to produce particularly satisfying results when used the Sierras.

Mark

[pierreterrier]

I experience ultra satisfying sound from my Sierra Towers (with Raals) with the following equipment:

-Turntable, VPI Classic 1
-Cartridge, Soundsmith Zephyr
-Amp, Marantz PM-15S2 limited edition reference series
-Speaker cables, 10 gauge Atlona

From my music lover background, I have never experienced sound quality like this (bass, midrange and treble) on any equipment I have heard or owned since the mid sixties.