Explain to me what I'm hearing from 45W to 80W

[andymok]

more power will drive transient better and handle back EMF better

 

[Roland]

I just tried it at very low volume, the difference is less noticeable, but STILL lightly noticeable. Once you crank it to even regular listening volume, the differences are very obvious.

You’re on the wrong forum because the view you’re expressing here is heresy. It’s like saying that the world is a sphere to the flat earth society (before circumnavigation). It is a fundamental belief that two amps which measure the same must sound the same (or more correctly neither have any impact on sound reproduction). Even wattage is largely inconsequential because you need a huge power increases to get a few extra db.

Threads on this subject are started every few days and have to be shut down because they can never be resolved. It’s symptomatic of the polarisation of views in modern society where opinions turn into belief sets and tribes with a particular belief establish echo chamber online communities of “people who share my view”. It’s not very scientific, but it’s the way of the world.

 

[Willem]

i do not have any experience with Class D amps. How do you think of them?

Class D amplifiers came of age with the Hypex modules, and with the NCore series in particular, that could be used by amplifier manufacturers. These modules measure better than almost any traditional amplifier, with the added benefit of low cost (i.e. e.g. about 1000 euros for a complete 2x350 watt into 8 Ohm power amp), small size and low energy consumption. Their designer then moved on to Purifi, for even better measurements (but at a higher price). Several of these Hypex and Purifi based amplifiers have been tested here, with quite spectacular results. I honestly do not think there is any point in spending more, even in the most elevated system, and the size and energy efficiency are an important added bonus, and all the more so in this day and age of global warming where in my view we should do all we can to reduce energy consumption, even with audio systems.

 

[solderdude]

You’re on the wrong forum because the view you’re expressing here is heresy. It’s like saying that the world is a sphere to the flat earth society (before circumnavigation). It is a fundamental belief that two amps which measure the same must sound the same (or more correctly neither have any impact on sound reproduction). Even wattage is largely inconsequential because you need a huge power increases to get a few extra db.

Threads on this subject are started every few days and have to be shut down because they can never be resolved. It’s symptomatic of the polarisation of views in modern society where opinions turn into belief sets and tribes with a particular belief establish echo chamber online communities of “people who share my view”. It’s not very scientific, but it’s the way of the world.

It CAN be easily resolved but requires level matched (blind testing) which is not as easy as it seems to some.
Those that actually have gone through the trouble know some amps sound the same and others sound different and why this is so.

No... not all amps sound the same (recent example here). There are plenty designed to sound different. There are also plenty of amps that do sound the same but measure different (I have not seen a single amp that measures exactly the same as another one) under equal circumstances.
Those amps, under NOT equal circumstances, in sighted AND blind conditions, can sound substantially different.
Then there are the fringe thingies where someone uses amp A and another person amp A but with totally different speakers and do not experience the same. Could be the load, could be the test method, could be the source, could be the circumstances. Without investigating every aspect we will not know.

In this particular case the test method is questioned where the OP does not. There is no resolve unless OP tests blind and level matched.

All is very easily scientifically explained but someone's personal experience (they heard it so it is true) is strong.
Also people hate to be wrong and think... I don't even need to test this or that way because differences heard are night and day.

 

[PeteL]

I just tried it at very low volume, the difference is less noticeable, but STILL lightly noticeable. Once you crank it to even regular listening volume, the differences are very obvious.

Again, I would like to know the source. What are you listening from to do the comparison? Is it the digital input or analog, and which device?

 

[PeteL]

It CAN be easily resolved but requires level matched (blind testing) which is not as easy as it seems to some.
Those that actually have gone through the trouble know some amps sound the same and others sound different and why this is so.

May I ask how the fact that the assessments are blind instead of sighted will help us resolve the "why"? It will only tell us if his experience is real or not, but why?

 

[DSJR]

In my time demming many amps over some decades, I think I can say *subjectively* that so many far eastern cheaper integrated models including the Denon's ancestors, could sound a bit 'weak' given a demanding speaker load. Fine with sinewaves and into an 8 ohm resistor, given a more demanding music signal and a real speaker load, the small cost-counted power supplies appeared to subjectively collapse.

The thing is, that little low cost Denon amp may well be perfect into smaller speakers at moderate volume levels (just like a small town car is around our crowded streets in the UK), but give the poor thing a difficult load and someone who wishes to use a good dynamic range (I couldn't give a stuff where the volume control is here as I'm trying to go beyond this, albeit in a subjective way) and I'm not at all surprised this little amp collapses. Nothing like a smooth big engined car for long runs where overtaking is needed and it's the same for larger scale audio reproduction.

I feel there are a number of things going on here and pinning it down to 'Watts per channel' at a certain distortion level isn't quite enough I feel.

Going back a few posts, getting a chance to listen to a now vintage Krell will be an ear-opener for the OP I reckon. Interesting how I found the 400i rather better balanced than the leaner toned (to me) 300 model - I'm going back twenty years now - when apparently the changes were more cosmetic than anything else . Got to say my experience of a FPB300 into small cheap speakers was huge fun, as said speakers developed a stature that they just didn't have with more conventional domestic amps. I confess I haven't used modern Class D designs which may well do much the same at a fraction of the used cost of a Krell (I wouldn't say older big Krells are particularly reliable either, but they hold value and are much loved by their owners - I sadly had to let my 50S go as I couldn't have it free-standing and it ran very hot* in the more confined space I'd earmarked for it. Distortion figures are mediocre by ASR standards though but still below audible levels.

* The plateau biased Krells can idle as cool as any other A/B amp, but give them some welly and they soon enter various stages of 'cooker mode' and need the space around them to prevent overheating.

 

[PeteL]

You’re on the wrong forum because the view you’re expressing here is heresy. It’s like saying that the world is a sphere to the flat earth society (before circumnavigation). It is a fundamental belief that two amps which measure the same must sound the same (or more correctly neither have any impact on sound reproduction). Even wattage is largely inconsequential because you need a huge power increases to get a few extra db.

Threads on this subject are started every few days and have to be shut down because they can never be resolved. It’s symptomatic of the polarisation of views in modern society where opinions turn into belief sets and tribes with a particular belief establish echo chamber online communities of “people who share my view”. It’s not very scientific, but it’s the way of the world.

I am not sure where you got that idea from. Amps are actually the electronic component in the reproductionchain where measurments vary the most, between models, but also across the range of operation in the same amp.

 

[Grumpish]

It CAN be easily resolved but requires level matched (blind testing) which is not as easy as it seems to some.
Those that actually have gone through the trouble know some amps sound the same and others sound different and why this is so.

A little bit of sense from solderdude - too much of this thread has been almost the same as found on the various cable sniffer forums when someone dares to start a "I couldn't hear any difference" thread - everyone just piles into the OP and blames them. In most cases testing is done with resistive loads - and speakers are far from that, and in the case of the KEF Q950 it is actually quite a difficult load as it drops to 3.2 ohms at low frequencies. It is easy to think that a lower powered amplifier (or a less well engineered one of the same power) might run out of steam much sooner.

 

[Koeitje]

The difference is night and day, but I guess I’m just fooling myself…

The wattage plays nothing here? 400W amp vs a 15W amp makes no difference?

It depends on your use case. If both don't clip or distort even through the highest peaks then it makes no difference indeed. But its easy to get a 15W amplifier to clip.

 

[Sir Sanders Zingmore]

It will only tell us if his experience is real or not, but why?

i feel like these sorts of comments can unintentionally get people defensive/hostile/upset etc.

I think it’s ok to examine the reasons for someone’s experience but no one should deny its reality.

 

[solderdude]

The issue here is that an explanation is demanded/asked by OP but some of the explanations are not accepted on either side.

It may well be 'synergy' thing between OP's speakers and his amps it could also be something else.
Without measurements by the OP, which have to be executed well, there will never be any consensus on what exactly is happening.

One thing is for sure, an amp that can provide 200W in 8ohm and about 300-400W in 4ohm may well be what the OP needs.
It is only 4dB louder than the 'best' amp he currently has.

 

[PeteL]

The issue here is that an explanation is demanded/asked by OP but some of the explanations are not accepted on either side.

It may well be 'synergy' thing between OP's speakers and his amps it could also be something else.
Without measurements by the OP, which have to be executed well, there will never be any consensus on what exactly is happening.

One thing is for sure, an amp that can provide 200W in 8ohm and about 300-400W in 4ohm may well be what the OP needs.
It is only 4dB louder than the 'best' amp he currently has.

Sure, I agree with this, but sometimes the difference ARE night and day, and are symptomatic of a real life PROBLEM, those are two fairly unpowerful amps, and in this case, I believe that the original question was not what amp can give me better performance than both, but why is one so much better than the other. Measurments could give us answer but maths, specs, and troubleshooting too. Blind test in this case are useful, but only useful if we don't believe the OP that the difference is "night and day" Blind test is useful if the small differences we hear are real or not, not night and day differences.

 

[Aerith Gainsborough]

Blind test in this case his useful, but only useful if we don't believe the OP that the difference is "night and day" Blind test is useful if the small differences we hear are real or not, not night and day differences.

One persons subtle is another ones "night and day".

Suffice it to say, that I heard people claim "Night and day" between headphone cables.

Since he claims "small differences at lower volumes", Blind testing would be useful.
I'm reasonably sure he drives at least one of the amps into clipping at loud volumes, so there might be large differences indeed.

 

[solderdude]

Measurments could give us answer but maths, specs, and troubleshooting too.

Sure, but unless someone with measurement-fu has the same amps/speaker combo under similar circumstances we cannot expect OP to provide us with clear evidence in the form of conclusive and well made measurements.
Specs do say something but are not conclusive here because the only 'spec' we can go from is speaker and amps specs from a manufacturer.
The only thing OP could possibly do is record the sound in his room but needs a good mic and ADC which probably aren't available either or a capture of the speaker signal (see PMA's test).

Some answers have been given as of the why and how and 1 or more may be correct in this case. Anyone's guess which one(s) they are.

 

[DSJR]

Some low powered amps I remember, 'soft clipped' gently and 'sounded' louder than they really were due to compression. Other amps offering higher power on paper, ran out of steam very quickly and 'hard clipped,' telling you in no uncertain terms you're overdoing it.

Music into various speakers opens up a huge can-o-worms, but as we all listen to different music and different average volume levels, I'd suggest the OP goes with his heart on this one, gets as much *clean* power as he can afford and which the speakers will hopefully handle safely, use the best quality (not necessarily expensive) sources he can and then hopefully put all this behind him and enjoy some tunes without worrying about where the volume is set, or whether the amp is going to distort

 

[FeddyLost]

You’re on the wrong forum because the view you’re expressing here is heresy.

I think unless we have some data about real performance of the amp into this exact load, we can't call such claim heresy.
In principle, I'd like to see distortion of amplifiers into real test load with impedance dips like i.e. BW or Focal floorstanders. But I think it will never be published as number will be incredibly bad compared to manufacturers' claims.
Since Denon power into 4 Ohms is declared at 1 Khz, most probably something bad is going on when signal becomes fullrange.
Also, there's no test data regarding distortion vs frequency at 4 Ohms, and, of course, into lower load.
Inside view tells us that it's standard class AB (i'd say, almost B) with low power linear power supply (transformar and 2 small capacitors), when CXA80 looks slightly better.

 

[Jim Matthews]

I think unless we have some data about real performance of the amp into this exact load, we can't call such claim heresy.

Yes, we can. Most of us migrated here to avoid wooly thinking and purple prose.

 

[PeteL]

Some low powered amps I remember, 'soft clipped' gently and 'sounded' louder than they really were due to compression. Other amps offering higher power on paper, ran out of steam very quickly and 'hard clipped,' telling you in no uncertain terms you're overdoing it.

Music into various speakers opens up a huge can-o-worms, but as we all listen to different music and different average volume levels, I'd suggest the OP goes with his heart on this one, gets as much *clean* power as he can afford and which the speakers will hopefully handle safely, use the best quality (not necessarily expensive) sources he can and then hopefully put all this behind him and enjoy some tunes without worrying about where the volume is set, or whether the amp is going to distort

Yes, I guess you worded it right, my thought also. I find the discussion interesting because we see I believe a lot of "binary" answers. One clips, the other not. Amplifier distortion is not binary, especially with what seem to be a load with more than average impedance swing, when those two amps appear to have different gain or input sensitivity and design. Amps don't work as linearly as we think and even with measurments, we don't get the whole story, It would need pages of measurments. Amps have gain stages, have input buffers, have differents ways to implement volume control. Dynamic compression can occurs before driving the amp into clipping. What was against in those line are that there is basically only two answers, it's either "You imagine this" or "You are lacking power". To me there is a lot of grey in between, and it is not uninteresting digging, with more info and analysis.

 

[PeteL]

Yes, we can. Most of us migrated here to avoid wooly thinking and purple prose.

Most of us mainly come here because we are interested in the science behind audio reproduction. The "why" Calling something heresy without demonstrating how so doesn't strike me as rigorous, I personally cannot from the data collected make that claim. I cannot make the claim that this is true neither. But that's the beauty of it, we can only try.