Stereophile | January 2017 Issue
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In my setup , yes.
I heard once Acapellas which are much less effective driven by an Einstein and it was for me best of show( Munich 2014).
Synergy rules
You chose not just _any_ tiny 2W amp though, you specifically chose one with puny power supply capacitance. Such amps tend to be SE classA in operation right? Or am I missing something important?
Hi
No,it is just to emphasize that a small amp with no special energy reserves can sound more dynamic paired with a right speaker,than a SS with a wrong speaker.
Big SS can and some have great energy reserves,and their energy reserves are not the reason why lower efficiency speakers sound more compressed(which was you initial comment).That is the reason i emphasize it.
Of course big SS does not always equate dynamic sound with high efficiency speakers,but this is another topic
A SE amp is by definition Class A.
Now this isn't clear to me, what 'no' means. Is it an answer to my question 'am I missing something important?'. Or its to deny that you chose a specific kind of 2W amp?
I agree that energy reserves are not necessarily relevant to how dynamic an amp sounds so I'm curious about the kind of 2W amp you introduced in your illustration.
I agree that an SE amp is by definition classA incidentally. I should have written them in the opposite order 'classA, SE'.
When did I mention 'energy reserves' in my initial comment? My memory's not as good as it used to be, but I don't remember mentioning them at all. Energy reserves only matter indirectly in my experience, what's more important is the impedance of the PSU over frequency (this tends to have fairly high correlation with energy reserves), and even that's not as important with certain kinds of amplifiers.
Hello opus
Sorry for the hasty answers ...a bit busy with expanding the premises and i have to be on top of things....
The "No" is to deny that i mentioned any specific 2W amplifier,i had to be more clear maybe....
So,your comment above implied that low efficiency speakers somehow lacked the dynamics of high eff speakers because of the lack on rock solid energy reserves from big power amplifiers that drive them.If i read your comment correctly.
All this back and forth is to show that this is not the case. I chose the two extremes in amplifiers, big SS with massive energy reserves(high capacitance,low ESR and ESL cap banks),and a puny SE 2W amplifier to the other spectrum for my example to emphasize that this is not the case,low efficiency will sound more compressed due their drivers and not because there are not good enough PSUs in current amplifier technology.Speakers is the main contributor to compressed sound.
Cheers
Stavros
No worries Stavros, we all have our various constraints on participation. I wasn't asking whether your 2W 'puny capacitance' amp was a particular one, rather whether it had certain identifiable characteristics, the most important of which to me would be whether it was an SE amp. If it was - and you do seem to confirm that's the case later down the post - then capacitance is largely irrelevant for that particular topology of amp. Which I'd say has a fighting chance for being the reason the designer didn't see fit to include a lot - with SE amps, more capacitance (and hence more energy storage) doesn't lead to superior dynamics.
The part of my post that you bolded (thanks for highlighting which of my words you're arguing against, it makes responding so much simpler!) was in the context of high powered amps. High powered amps can't in general afford to be SE because that topology is rather inefficient, even when designed for a specific load impedance. So historically high powered amps have tended to be classAB and its this kind of amp which places extreme demands on the PSU. Its classAB amps that tend to be called for with less efficient speakers and its my hypothesis that the lack of subjective dynamics is down to the amps being noisy, not primarily down to the efficiency of the driver(s).
So it seems to me you've been tilting somewhat at windmills in your response - my argument has not been about the necessity for rock solid energy reserves, rather the need for low impedance power supplies to feed higher powered, typically classAB amplifiers.
Does any of that help to clarify? We're still at disagreement over whether its primarily speakers or amps that are the major contributor to compressed sound but hopefully we can disagree for the right reasons. I'd be interested in the results if you swapped your SE 2W amp for a 2W classAB chipamp (add plenty of supply capacitance to taste) to see how good the dynamics of your horn turn out to be in this particular case.
Hi
It is not just the voice coil heat up or the Xmax limitations.These were only an example of how far apart can two transducers be in their effectiveness converting electrical energy to acoustic energy.
That is why i said even a tiny 2W would beat a welder-spec amplifier if the latter drove X and the former Y.
The example's horn will convert 50% of it's input energy into acoustic energy,where as the typical midwoofer would struggle at 0.4% (not a typo).
You cannot expect a driver to receive 125 times the energy,and behave as linear.Unfortunately there is no way around it.And i say unfortunately, because it would be nice to have an alternative to a half a tonne midbass horn.....but when you hear one,there is no going back
I am enthralled by these two posts...they are incredibly clear, make a lot of sense. And I have to say, REALLY now intrigue me in regards to [well] designed horns. I have heard some and been underwhelmed. (i have posted those thought in this Forum but will NOT rename them to avoid distracting from my main message). In particular, i am most intrigued by the half-ton mid bass horn comment and the description of horn and cone technical characteristics.
I categorically wish to avoid a horn v cone debate. (I also stating up front I am aware that Aries Cerat has a gigantic mid-bass horn in their Contendo Reference speaker which i have always wanted to hear...and i wish to avoid any discussions about manufacturers being biased, or pushing their 'agenda'...and stay on target for a few questions from STAVROS, MORRICAB, or ANYONE who is happy to provide technical guidance in regards to a few questions on horns:
1. THERE MUST BE SOME DISPERSION, POWER AND LOUDNESS MATH OF 'SOME AMOUNT' THAT RELATES TO HORNS AT THE MID BASS AND LOWER BASS LEVELS. Most of the major horn companies that are going for full-range and full-dynamic capability have bass horns that are absolutely immense. Is it simply that to get a horn to generate deep bass at 115-120db peaks (kettle drums, deep house music, etc), this math basically forces the horn to be gigantic? (ie, flip side is that the reason we see cones in subwoofers, bass towers is because the equivalent horn or panel would be way too large for a domestic environment?)
2. Does the sheer size of the horn effectively allow for a kind of 'non-electric' form of amplification of the original bass being generated somewhere behind the gigantic horn? Is that the 'simple man's' physics behind how the horn generates loud, powerful bass?
3. Do gigantic horns for bass suffer from major vibration issues like cones (subwoofers, woofer towers...even the internal vibrations from full range speakers can cause internal design challenges to the attached mid/upper frequency cones). Is it the cone movement that causes these vibrations...or the power of the actual bass waves themselves?
4. WITHOUT getting into 'i am better, or you are not' fighting, i would like to ask about the challenges inherent in cone bass being blended with horn bass. In an ideal world with NO PRACTICAL CONSIDERATIONS, does a designer of horn speakers ALWAYS seek to have horn bass? (again, NO practical considerations whatsoever).
5. Are there mathematical and physical differences in the way that horns generate deep bass (vs cones) such that those little differences ultimately create dischordance between the quality of sound at the mid/upper levels vs the deep bass levels in an ideal design?
No worries Stavros, we all have our various constraints on participation. I wasn't asking whether your 2W 'puny capacitance' amp was a particular one, rather whether it had certain identifiable characteristics, the most important of which to me would be whether it was an SE amp. If it was - and you do seem to confirm that's the case later down the post - then capacitance is largely irrelevant for that particular topology of amp. Which I'd say has a fighting chance for being the reason the designer didn't see fit to include a lot - with SE amps, more capacitance (and hence more energy storage) doesn't lead to superior dynamics.
It is not my Se amp or anyone's,it was "just a 2W amplifier" to make the point given...Anyhow....
And yes SE topology does like high quality capacitor banks.Who ever said the opposite?
The part of my post that you bolded (thanks for highlighting which of my words you're arguing against, it makes responding so much simpler!) was in the context of high powered amps. High powered amps can't in general afford to be SE because that topology is rather inefficient, even when designed for a specific load impedance. So historically high powered amps have tended to be classAB and its this kind of amp which places extreme demands on the PSU. Its classAB amps that tend to be called for with less efficient speakers and its my hypothesis that the lack of subjective dynamics is down to the amps being noisy, not primarily down to the efficiency of the driver(s).
It never said anything about Se vs SS,class A or class AB,nobody mentioned this so far... my point is that the amplifier's PSU and amplifier in general does not have anything to do with the superiority of HE vs LE speakers over dynamics.So no windmills,my posts were clear from the beginning on what i was arguing about.
So it seems to me you've been tilting somewhat at windmills in your response - my argument has not been about the necessity for rock solid energy reserves, rather the need for low impedance power supplies to feed higher powered, typically classAB amplifiers.
Rock solid energy reserves(high capacitance,low ESR/ESL) is another phrase for Low impedance power supplies.
I do not see any windmills,again, i only see trouble in understanding the basics before going further.
Does any of that help to clarify? We're still at disagreement over whether its primarily speakers or amps that are the major contributor to compressed sound but hopefully we can disagree for the right reasons. I'd be interested in the results if you swapped your SE 2W amp for a 2W classAB chipamp (add plenty of supply capacitance to taste) to see how good the dynamics of your horn turn out to be in this particular case.
I see that you have taken the hypothetical 2W amp,used in my example ,that it is somehow my reference,and that i do like low capacitance...How did you ever came to this conclusion?Who said the the mentioned horn performs the best with the example's 2W amp?Is my english that bad?
Again,i said,that a high efficiency horn,ANY horn,with ANY small power amplifier,will outperform ANY conventional low efficiency driver ,driven by a very high power amplifier,because of reason X or Y.From all this,all you did understand is that my reference for driving my horn is a 2W amplifier?
i think i will pass on anything AB,chip or not
Stavros
It's both the speaker and the amps that can contribute to a compressed sound. I have heard, in particular, Class AB amps with a lot of negative feedback sound compressed and unable to express dynamically.
Puny power supply capacitance...perfect
Non critical chokes.....perfect
Low DCR......perfect
Low gauge hookup wire.....perfect
Less than 2W ......perfect
There's more than one way to build a SE DHT amp.
Cheers
Blue58
I am enthralled by these two posts...they are incredibly clear, make a lot of sense. And I have to say, REALLY now intrigue me in regards to [well] designed horns. I have heard some and been underwhelmed. (i have posted those thought in this Forum but will NOT rename them to avoid distracting from my main message). In particular, i am most intrigued by the half-ton mid bass horn comment and the description of horn and cone technical characteristics.
I categorically wish to avoid a horn v cone debate. (I also stating up front I am aware that Aries Cerat has a gigantic mid-bass horn in their Contendo Reference speaker which i have always wanted to hear...and i wish to avoid any discussions about manufacturers being biased, or pushing their 'agenda'...and stay on target for a few questions from STAVROS, MORRICAB, or ANYONE who is happy to provide technical guidance in regards to a few questions on horns:
We can start another thread,we already butchered this one
1. THERE MUST BE SOME DISPERSION, POWER AND LOUDNESS MATH OF 'SOME AMOUNT' THAT RELATES TO HORNS AT THE MID BASS AND LOWER BASS LEVELS. Most of the major horn companies that are going for full-range and full-dynamic capability have bass horns that are absolutely immense. Is it simply that to get a horn to generate deep bass at 115-120db peaks (kettle drums, deep house music, etc), this math basically forces the horn to be gigantic? (ie, flip side is that the reason we see cones in subwoofers, bass towers is because the equivalent horn or panel would be way too large for a domestic environment?)
A horn is designed having a strict bandwidth to cover.A good rule of thumb is two-three octaves.The horn's cut off frequency is dictated by it's length and mouth area.A horn with cutoff of 100Hz will have double the length and double the mouth area of a 200Hz horn.So you can see it is the cut off frequency that dictates the size.
2. Does the sheer size of the horn effectively allow for a kind of 'non-electric' form of amplification of the original bass being generated somewhere behind the gigantic horn? Is that the 'simple man's' physics behind how the horn generates loud, powerful bass?
A horn is an acoustic transformer.Just like a mechanical transformer(gear box in your car) or electrical transformer,it changes the acoustic impedance that the driver that is loaded with.A direct effect of this is a very big increase in efficiency,but since there is no free meal,you loose directivity(a good thing in my opinion)
and loose bandwidth(for a specific horn).also a good thing.
3. Do gigantic horns for bass suffer from major vibration issues like cones (subwoofers, woofer towers...even the internal vibrations from full range speakers can cause internal design challenges to the attached mid/upper frequency cones). Is it the cone movement that causes these vibrations...or the power of the actual bass waves themselves?
Like all structures,metal,wooden or composite,everything vibrates.Bigger stuff seem to vibrate more
4. WITHOUT getting into 'i am better, or you are not' fighting, i would like to ask about the challenges inherent in cone bass being blended with horn bass. In an ideal world with NO PRACTICAL CONSIDERATIONS, does a designer of horn speakers ALWAYS seek to have horn bass? (again, NO practical considerations whatsoever).
Bass horns must be big,and are much more expensive to manufacture.It all boils down to what is the least compromise,in size,weight,cost.
5. Are there mathematical and physical differences in the way that horns generate deep bass (vs cones) such that those little differences ultimately create dischordance between the quality of sound at the mid/upper levels vs the deep bass levels in an ideal design?
The mathematical models for a particular horn flare type is the same,for all frequencies.What is world apart,is their implementation... for example how an actual midrange horn can be constructed closer to the ideal shape with proper materials,where as the bigger the horn,the more you deviate from the ideal.
Cheers
(...)
Please quote and answer like all others in the standard WBF way. I appreciate your posts, but could not go through your previous ones. And no one will be able to answer to you.
Please quote and answer like all others in the standard WBF way. I appreciate your posts, but could not go through your previous ones. And no one will be able to answer to you.
(...)
Please quote and answer like all others in the standard WBF way. I appreciate your posts, but could not go through your previous one. And no one will be able to answer to you.
Thanks,will do from now on
thank you Micro, for the kind words.
and yes, I understand completely. we all search for the right strategic pieces in our systems which end up giving us more and more musical goodness as we unleash it from the bonds of system discontinuities. the 458's continue to show me more and more musical truth with each layer of restriction I remove system wide. optimizing any amplifier is never trivial. personally I do think the 458's particular combination of attributes is unique and is quite amazing to enjoy every day. I never take the 458's for granted.
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It's fairly well known that classA amps are very transformer dependent. Everyone whom builds Nelson Pass's Firstwatt designs swears a larger transformer sounds better, but increase the capacitor bank doesn't appear to do the same thing. It's not surprise, and historically consistent, that tube amps in classA don't seem to respond to massive capacitor banks either.
And how are dynamics defined? For me it's changes in volume. Sometimes they these changes have huge differences in crest factor, requiring lots of power to be 100%, and others simply do not. Often what sounds loud and powerful to us, simply is not, in terms of power. Now different speaker loads might change that factor where the amp is now asked to produce a lot more current, but usually this isn't the case with high sensitivity speakers.
So I'm sure the SE he prefers doesn't ultimately have the highest crest factor capability, but it sounds dynamic. The very impression of it gives you the idea there's power there not because of wattage, but representing the power in the music. In order to achieve this with electronics it has more to do with what I like to describe as 'current being in phase'. That's not exactly what's happening, but the description is easy to understand. SE tube amps may have an easier time achieving that goal. For example they can use all film caps so the values of capacitance and inductance are less at odds with each other since they're closer and less likely to sink current. But the real trick if figuring out how to get more capacitance in without the drawback, so you've got it all.
Not all classA amps are SE, and there's an even smaller subset of SE amps which I reckon are insensitive to power supply noise - they're ones I call 'power supply invariant classA'. I've looked at a few of Nelson's published schematics and not noticed any which fall into this last category.
I don't have a definition - its all subjective. Suffice to say I know it when I hear it. 'Jump factor' would be another way to talk about dynamics, the ability of music to trigger my startle reflex is a sign I'm getting good dynamics.
I'm not sure I'd call ripple noise, sure, technically, but I call it ripple for a reason. If you mean what the cap banks should capture, well, I don't think they do much of that honestly until you do something like your CLC.
Dynamics are always better with current in phase. The current must be as immediate as the voltage signal. Sometimes this happens easily, sometimes it's luck, sometimes there's no hope! Sad fact o'life for most. It's the difference between the snaps of drums sounding dynamic with regular volume and no huge crest factor, and being flat waiting for a big crest. Most high end systems I hear will have one or two points in a song where the crest factor is so huge that despite the current problem, even coming in late, it's very loud and "dynamic"(ish) sounding. The problem for me is that as I've been saying drums should have snap whether someone is giving the god-thump or just gingerly going along. In fact I'll take underpowered amps that make 98% of the music sounded exciting vs ones that do it louder for 2%, if forced to choose (hopefully I'd just get more sensitive speakers). And yes, I think what I'm talking about is jump factor, but for the whole album not just 2%.
Dynamics are always better with current in phase. The current must be as immediate as the voltage signal. Sometimes this happens easily, sometimes it's luck, sometimes there's no hope! Sad fact o'life for most. It's the difference between the snaps of drums sounding dynamic with regular volume and no huge crest factor, and being flat waiting for a big crest. Most high end systems I hear will have one or two points in a song where the crest factor is so huge that despite the current problem, even coming in late, it's very loud and "dynamic"(ish) sounding. The problem for me is that as I've been saying drums should have snap whether someone is giving the god-thump or just gingerly going along. In fact I'll take underpowered amps that make 98% of the music sounded exciting vs ones that do it louder for 2%, if forced to choose (hopefully I'd just get more sensitive speakers). And yes, I think what I'm talking about is jump factor, but for the whole album not just 2%.