Can anyone explain how diff amps give diff soundstage and stronger bass/treble?

Background: Headphone amps and power amps share a common characteristic. They can run out of power two ways. The background information is that power is defined electrically as the product (multiplication) of current and voltage.

In some sense all the listener knows is that the sound isn't loud enough. It could be because the amplifier can't deliver enough voltage, or it could be because it can't deliver enough current.

As you already know, problems obtaining sufficient loudness with low impedance speakers or headphones can be due to the amplifier running out of undistorted current.

Problems obtaining sufficient loudness with high impedance speakers or headphones can be due to the amplifier running out of undistorted voltage.


Sounds like you have been reading one of those errr marketing-oriented highly speculative headphones-only web sites. Some of them seem to intentionally ban posters who don't mouth the site's corporate line.

Fact of the matter that building a great headphone amplifier should be about the easiest thing in the world. Both the voltage and current requirements can be easily provided with equipment that at most runs say $50 for a straight-up headphone amp that does not provide channel cross-feed or other psychoacoustic assists.


Sounds about right, or even a bit spendy on the amplifier side.


I guess that headphones that are edging towards $1k are cheap compared to $10K speakers.



A lot of high end audio equipment pricing seems to be based on what the market will bear. There are always people with more money than brains. ;-)



Depends on what you think "better sound" is. If your situation would be more preferable with more treble then an amp that has non-flat frequency response (normally considered a flaw) might be more preferable to you.



In recent posts someone mentioned a technical flaw with it, I think.


Adding current capacity that avoids audible distortion is a good idea, but adding current capacity that does not cause the signal delivered to the load to be audibly cleaner has no benefits.

The current requirements of headphones is generally microscopic compared to speakers, so there is no reason for a headphone amp that can drive a given set of headphones at reasonable level without audible distortion to be inordinately expensive (more than $50 per headphone served).

Headphones are different from speakers in that they are more sensitive to distortion at low sound levels. When you wear headphones you are more isolated from surrounding environment, which means that you hear sounds at lower level, which otherwise will be masked by background noise in the room. Thus it is easier to hear flaws in components or record itself using headphones.

What makes you think so? Or, to put it another way, what do you mean by small? IF you mean measurable differences, then yes, but there are measurable differences between just about anything. If you mean audible differences, they are rare, assuming you're taking about two solid-state amplifiers that are not being pushed beyond their design limits.


I'm not familiar with those models, but again, the FR of almost all solid-state amps is as close to ruler flat as your ears need.


Well, if one amp has a channel imbalance—but that won't affect the width of the soundstage much, just its center.

Look, it's impossible to say "never" in a case like this, but it is possible to say, "highly unlikely." My guess is you're reading reviews and/or user comments extolling the great soundstage of some amp or other. The proper way to read such comments is to assume the writer, whatever his reputation, is talking through his hat. Someone who understood amps and wanted to find out if there were differences among them would not be looking at soundstage at all. He'd be looking at distortion and frequency response. Differences there could have an impact on soundstage, but it's a secondary effect.

In other words a properly operating amplifier fed a clean signal should give you very nearly the same sound as the next amp. Depth of the soundstage is created between the ears. Its largely a psychoacoustic effect. I find decent tower speakers tend to give me the best vertical soundstage over smaller monitor/bookshelf speakers. Of course this has a lot to do with the layout of the drivers.

Audio writers/reviewers I think have a Rolodex (or maybe a dart board?) they spin that has different phrases and words - like "a veil was lifted". Gawd almighty - I wonder who first coined that one? "I heard things on (insert fav CD here) I'd never heard" Etc etc. Don't get sucked up in their semantics - its the tools of their trade and how they make their living. How could the magazine they write for make a living if they used the same verbiage for an Emotiva amp as they do for a Krell or McIntosh? Those brands advertising budget far exceeds Emotiva's budget.

But thats where the state of the art of amps is - they all pretty much amplify. Can one brand project a better soundstage and drop the veil lower than another brand? Good question. If it does for you - good. I have a couple of cheap Acurus amps and they sound wonderful to me! And I get to enjoy great music at a reasonable price.

I knew a guy years ago when I was still working that had about 80K into a 2 channel setup. It sounded absolutely wonderful - stunning actually. My system is damned near as good for considerably less - about $6k. The trouble with that guy is he never really got around to listening to his system very often - he was too busy tinkering with it. I have another friend that loves telescopes and has 5 or 6 very expensive ones - but he seldom looks up at the night sky. Those guys are tinkerers - can't leave things well enough alone long enough to enjoy what they have. I guess they are just wired different than I am.

You might find this an interesting read

http://nwavguy.blogspot.com/2012/04/what-we-hear.html

you also might want to consider his O2 amp design

(no affiliation - haven't tried the amp)

Well, some might argue that it's created by the interaction between the speakers and the room.

But it's still not the amp's doing.

There is an interesting process that the listener's brain implements that tends to vastly reduce his perception of the sound of the acoustics of the room he is in. One of my friends calls this "Dereverberation". I'm sure there's a more technical name, but his name sticks in my mind. It seems to be related to the Cocktail Party Effect.

I notice this at live recording sessions - the mic feed always sounds far more reverberant over the headphones than what I hear, if my ears are at the same location as the mic. There's something about what the mic & etc. do that works against Dereverberation. Thus we dereverberate what we hear live, but we are far less successful at dereverberating the recording.

Of course no standard amplifier is going even try to apply this kind of complex processing to the sound, any more than an amp is going to compensate for the failings of the speaker's crossover. Yet, people tell us this happens with their favorite amp all of the time. The place where this all comes together is the listener's brain where he gets his brain's pleasure center stimulated by the thought of listening to his favorite amp, which he confuses with the same part of his brain being stimulated by improved sound quality.

People say - why mess with the guy getting pleasure from that amp, and I see that in a way. Problem is, he's recommending that I run out and buy his favorite amp, which probably won't have the same effect on my brain's pleasure center as it does for him because when he listens to it. He remembers his previous pleasurable listening sessions which I can't possibly experience for myself unless the amp actually improves sound quality.

If you actually improve sound quality, then that can reliably produce pleasure for all who follow the advice, but if the recommendation is based on sentimental thoughts related to personal experiences, pleasure is far from being assured.

So....what about tubed gear?
Can tubes change the soundstage, or just color the presentation so that one "thinks" its broader and/or deeper?
Is this also just a expectation bias...or is it something else...
Are all them that buy tubes to change the soundstage just fooling themselves?....or is there something to it?

It's well known that deep and tight bass even if played very loud is due to big input transformer and large capacitors....it's not the same if 50 w amp has 90 w transformer or 180 w...both can sound very well but the last will bring more control in bass and with that more space & dynamic

That's ok. Its no different than the guy who drives a sports car or the guy who constantly details and 'tinkers' with it. Too each his own. Everyone approaches hobbies a different way. If they are happy doing it, more power to them.

I had a similar experience. I'm not real good at computer networking but I spent an awful lot of time setting up a wirless router, setting up a remote access point, upgrading my denon 3311ci to airplay, and getting its internet radio to work, for a capability I rarely use. I guess I did it because I could or wanted to prove that I could!

????

I now of no home mainstream audio gear made in the past 50 years that has an input transformer. Tubed audio gear usually has output transformers, but tubes haven't been mainstream since the 1970s.

Deep tight bass first and foremost comes from capable speakers interfaced well with the room that they are in.

Even the lightest weight mainstream home audio gear hangs together down to 30 Hz. Very little music or even sound effects in movies needs response below 30 Hz to sound tight and deep. The lowest string on a 5 string bass guitar resonates around 32 Hz, and only the largest pipe organs have pipes that go any lower.

Good response below 30 Hz is more about visceral feeling.

Agreed

I can actually guarantee with my speakers that changing their placement has a 1000X affect on bass and sound stage than ANY amp I could EVER put into the chain. I can easily bloat the bottom end and collapse the sound stage just by moving them.

It took me a day + 1/2 to mess around with placement and toe to get my speakers optimal in the room.

You right...my English..eh...I was speaking about power transformer..sorry...I had Marantz amp PM 8000 - was sounding well but with small power transformer and not huge capacitors,was lacking the deep bass nature ....then came Ken Ischiwata,put larger power transformer,large capacitors and made whole thing 500 $ more expensive...in fact mostly whole electronic was the same but the bass was much better...this was my point...the power supply is important as well

I have no doubt that after all this time, money and trouble, that you perceived that the amp's bass was better.

Thing is, at approx 25 pounds for a 100 wpc stereo integrated amp, this product was not the least bit lightweight to start with.

Without further confirming reliable evidence, it is hard to escape the opinion that your perceptions were based on expectation bias and/or pride of ownership.

On balance, this review suggests that Marantz's engineering may not always be optimal, your experience may be typical.

http://www.stereophile.com/content/m...low-april-2010

This chart raises some concerns in my mind:



It begs the question - what else slipped through the cracks?

Apparently, you don't always get the best engineering when you pay a premium price.

Tube amps can definitely sound different, for a couple of reasons. The differences, technically, are going to lie in distortion and frequency response. Those might manifest themselves in changes in soundstage, but it's much more likely that they are imagining it. Read enough reviews abut the soundstage of tube amps, and you'll imagine the same thing.

Image and soundstage are two concepts that can be explained by psychoacoustics discipline.

IMO they are not related to the preamp, amp, the source or any other audio gear .. or at least not directly with due exception of loudspeakers.

In any case, the image and soundstage have nothing to do with the amp class or type.

So true....however the good power supply will improve the sound in case of a sudden huge power demand like when large orchestra plays forte fortissimo...and if you have drum with two heads like gran casa then you need boxes with high efficiency or amp. with good power reserve...generaly speaking of course...there are many other facts playing significant role as well...power supply is one of the keys

I don't think you understand the dynamics of music and power amplifiers, but it seems that not many other people do, either.

Audio power amplifiers are designed and tested in accordance with US law to perform on the test bench, with steady sine wave test signals. The energy content of even heavily compressed music is at the most only about one eighth (1/8, 12.5 percent or about -9 dB) or less of that of a sine wave test signal with equal peak amplitude.

That means that when there is a sudden demand for power when the orchestra plays fortissimo, the amplifier still has a reserve of about 8 times or more energy than is being required. The rest of the time, the reserves are even greater. They are equal to dozens, hundreds or thousands of times what is needed.

Seems unbelievable, No? To test this theory I once built a power amplifier with a current-limited power supply that could only deliver a fraction in terms of continuous power of what it would take to amplify sine wave test signals with the same peak amplitude as the music. If the the regulated supply's current limit was exceeded, it would turn off until manually reset. I hooked this to a speaker whose impedance was less than 4 ohms and played compressed rock music (worst case - sustained peaks), turning it up until it clipped, which was very loud. The current-limited power supply never tripped out.

I was prepared for this by the dozens of power amplifier ABX tests that we have done for decades. I've never seen a situation where overbuilt power supplies had any audible benefits.

People see large heavy amplifiers and the mass and weight makes them expect better sound. Journalists have told them this is so for years. Even many engineers believe this is true because of their experiences in laboratories doing sine wave testing.

So, without experimental controls such as double-blind testing, and comparisons to equipment that is not overbuilt, what they see strongly influences what they perceive about sound quality.

If we examine what is known about human hearing, we find that our ears do most of their processing to perceive directionality and therefore soundstaging, using Head Response Transfer Functions (HRTF). It has been found that processing artificial and mono sounds with HRTFs creates highly convincing perceptions of directionality and sound stage imaging. At lower frequencies, interaural time delays (ITD) are also significant.

Compared to the distortions that are can be added by modern power amps, preamps, and digital music players, HRTF and ITDs are huge. The distortion in even medocre examples of audio electronics are vanishing in comparison.

In contrast, the distortions in speakers, rooms, and even vinyl and analog tape players are sometimes comparable to the changes that are involved with HRTFs and ITDs.

I've never heard a soundstage difference in DBTs involving modern electronics including digital music players. If soundstaging differences were there, they should make reliable detection easy. When we artificially introduce the kinds of frequency response and timing differences that relate to ITDs and HRTFs we easily hear differences in DBTs.

Good tubed gear that represents the SOTA of tubed electronics right before the advent of SS can be very good. It can come out as being indistinguishable from the best modern SS gear in DBTs.

Unfortunately, a lot of modern tubed gear has sonic defects engineered into it in order to give it "tube sound". Some kinds of modern amplifiers, the so-called SETs are such extreme examples of being engineered to sound imperfect that they use design principles that haven't been found in the best tubed equipment since the 1930s. For example SET amplifiers discard the benefits of push-pull amplification which has been used in any tubed audio power amplifier with pretensions of quality since the 1930s.


Yes.


The something else is there and can be found in lab tests of some tubed equipment. I can see it in Stereophile tests of tubed amplifiers:

Contrast this measurement of what I would consider a *good* tubed amp:



with this tubed power amp:



Look carefully because the variations are graphically about the same size or even smaller in the second graph, but the vertical scale is 4 times larger so the frequency response variations are actually about 4 times larger. Is this intentional obfuscation? I would hope not ;-)

I would judge the first amplifier to have excellent potential for sounding the same as the proverbial piece of wire, while the second amp could probably be detected by ear in an ABX test. It would slightly color musical timbre, and if the speakers it drove didn't have matched impedance curves, soundstage shifts might be heard.

Just for reference - a good SS power amp:



Again notice the differences in vertical scale. The vertical scale is about the same as the first tubed amp.



It all depends. As I've shown, tubed amps can be built so that they are largely free of audible colorations, or not.

Nice explanation Arny. Thanks!

That was an excellent explanation......Thanks.

So they can/do make a difference, its not necessarily "imagined"....it comes down to accuracy, and preference.

Wow....very interesting......according to You what makes 2 amps that have the same output power sound so different in bass...the one has very tight and deep bass and the other ( with the same boxes) sounds without strong attack however still very nice but no or poor dynamic?

Your brain. Or a level mismatch. Take your pick.

What 2 amps?

technically, a good amplifier shouldn't color the source material at all, in my humble opinion.

Richard Clark actually offered a $10,000 reward to anyone who could prove that two different amplifiers sound "differently" within specified criteria (no distortion, equal power output, etc) about a decade ago, and so far, nobody has succeeded in collecting that prize.

That said, if you want a good amplifier, make sure it has a good power supply. The reserve power the amplifier can produce is the key to avoiding clipping, which is pretty much what typically causes distortion that we find unpleasant to the ear.