Veselchak U
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Topping LA90 Review (Integrated Amplifier)
- Thread starter amirm
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Thanks for the warning! But the trouble is that I don’t know which of the two “volume control” methods provides the LEAST DISTORTION, NOISE and other nastiness (including IMD) - and I have no way to measure different superpositions of these two devices!
I tried "by touch" to adjust the volume control of the amplifier to 2 watts of power (I understand that this is a stupid method - power by touch, but I saw on the graphs that the LA90 amplifier gives the least distortion at (starting from) 2 watts given to 4-ohm speakers) and then I adjusted the volume using the LA90SE DAC. It does not matter at all the reason why I thought / fancied that such use gives me a WORSE sound than when using the DAC in the "DAC" mode (i.e. not even at 0 dB, but with off (?) an attenuation contour?).
Obviously, the reason for this my opinion may be self-hypnosis or anything else that is completely NOT related to the actual sound quality - but the sadness of this situation is that I DO NOT have either hardware or calculation (mathematical) tools for research (search!) the best method for volume control!
Even if the difference in sound quality is inaudible, we try to purchase BETTER QUALITY EQUIPMENT. Same here: I want to know which volume control method provides the highest quality compared to an alternative volume control method? Please, audio SCIENCE forum specialists, help!
Sokel
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I'm probably not the right person to ask as I always put safety first,so my advice is always to make sure you don't blow your speakers and most importantly your ears.
That dictates that either you have some fixed same level on the amp's side and you control the volume by the dac...
...or put the DAC at around 0db (or a little less considering some conditions like intersample overs,Windows mixer limiters,etc)and control the volume by the amp if it's an analog one.
Theory can tell lots of things,you can see at the measurements (SINAD vs Level,IMD vs Level) at which point you have the better performance but sometimes implementations vary and you will know for sure only by measuring yourself or wait until someone do it in detail.
Have a look at the last 2-3 pages of this thread for example.
PCM vs DSD
Did a little comparison and I was wondering if any friend with better gear here has tested this. Results you're about to see is probably narrowed to the specific DAC but it's interesting to see how it handles things differently. I will not try to decipher the results other that DSD seems much...
www.audiosciencereview.com
Further more every single condition can degrade results,don't expect the perfect analyzer's ones that are isolated.
As you said though,all this are probably inaudible and by far,so it's only the vice of the knowing that everything does well.
Veselchak U
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I think it’s a matter of sound reflections from the walls, you should drown out the listening room, at least put large soft toys in the corners opposite the acoustics, then at a lower volume you will hear a more correct sound
Thank you very much for your help!!!I'm probably not the right person to ask as I always put safety first,so my advice is always to make sure you don't blow your speakers and most importantly your ears.
That dictates that either you have some fixed same level on the amp's side and you control the volume by the dac...
...or put the DAC at around 0db (or a little less considering some conditions like intersample overs,Windows mixer limiters,etc)and control the volume by the amp if it's an analog one.
Theory can tell lots of things,you can see at the measurements (SINAD vs Level,IMD vs Level) at which point you have the better performance but sometimes implementations vary and you will know for sure only by measuring yourself or wait until someone do it in detail.
Have a look at the last 2-3 pages of this thread for example.
PCM vs DSD
Did a little comparison and I was wondering if any friend with better gear here has tested this. Results you're about to see is probably narrowed to the specific DAC but it's interesting to see how it handles things differently. I will not try to decipher the results other that DSD seems much...
Further more every single condition can degrade results,don't expect the perfect analyzer's ones that are isolated.
As you said though,all this are probably inaudible and by far,so it's only the vice of the knowing that everything does well.
I didn't read all your posts, but something you might not have considered is that your speaker could be the reason for the better sound at higher levels. Some speakers (large ones especially), can really start to sound great once they're at med-high to high levels. They seem to just "come into their own" when louder - I don't know the technical reason for it, but if I had to guess I'd say it probably varies speaker to speaker and is a combination of things, and it's likely room interaction contributes as well). The LA90 is so clean compared to 99.999% of other amps, and since it also has a low output impedance, it does a near perfect job as an amplifier. These properties might be the reason you didn't notice with other amps
It's something to consider!
Also, best practice for minimum distortion is to use your DAC at its full output level and use the volume control on the front of the amp.
If you're using a PC, put all of its volume controls in the way of the signal to 100%, and try to use WASAPI or ASIO. Don't resample or modify the signal with any DSP
It has jack ports in center of xlr. So you can use RCA - Jack cables. But in balanced it works best.
If I understood your question correctly, then keep in mind that the XLR connectors of the LA90 are COMBINED and you can also plug RCA plugs into them - but whether they can be UN-balanced, I don’t know.
I am VERY grateful to you for the most detailed clarifications and explanations! Thank you very much!!!
Quite by accident, just today, before I saw your answer, I increased the volume to 70 - 75 - (80 dB in peaks). I don’t know if the application works correctly on my phone - the numbers are from it. The result was exactly what you described: the sound became better!
But I can’t use (such) volume to improve the sound - my neighbors will take me to jail... And besides that, I’ll go deaf...
Is there another way - besides looking for speakers that sound good at low volumes too?
Do you know such speakers? How to find them??? EVERYONE wants LOUD, VERY LOUD sounds - maybe there are no speakers in nature with a range of 20-30 Hz - 20,000 Hz that are capable of reproducing quality music quietly?
Once again, thank you SO MUCH for all your advice, clarifications and warnings! Thank you very much for your kindness!
Hello,
I was allowed to compare the yba pasion ia350a amplifier with my LA90 - in my apartment. How can you explain that the unprecedentedly magnificent LA90 sounds worse than an amplifier with only 95 dB signal-to-noise ratio (I couldn’t find any other measurements)??? I compared at all volume levels available on the LA90, including in mono configuration. If there is no distortion, if we have a direct wire, then how can we explain that it sounds worse (there are no details, especially in the highs - but I’m only talking about what is obviously below 12 kHz).
Thanks for explanation!
I was allowed to compare the yba pasion ia350a amplifier with my LA90 - in my apartment. How can you explain that the unprecedentedly magnificent LA90 sounds worse than an amplifier with only 95 dB signal-to-noise ratio (I couldn’t find any other measurements)??? I compared at all volume levels available on the LA90, including in mono configuration. If there is no distortion, if we have a direct wire, then how can we explain that it sounds worse (there are no details, especially in the highs - but I’m only talking about what is obviously below 12 kHz).
Thanks for explanation!
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blind listening with levelled gain? if the answer is yes, i believe you, the YBA sounds better (to you).
If the answer is no ... well, i don´t believe you literally
... the YBA CAN sound better ... or not (to you).In other point of view, remember that higher SINAD "it means" a better internal engineering ... but you don´t need more than 70-80dB in the real world to be indistinguishable. Don´t think better SINAD translates directly to better sound, that´s a great misconception.
Yes, the comparison was made not only at the same volume, but sometimes even at a volume that was CONSCIOUSLY increased on the LA90 to check whether it would sound more intelligible, more precise and fuller.blind listening with levelled gain? if the answer is yes, i believe you, the YBA sounds better (to you).
If the answer is no ... well, i don´t believe you literally
In other point of view, remember that higher SINAD "it means" a better internal engineering ... but you don´t need more than 70-80dB in the real world to be indistinguishable. Don´t think better SINAD translates directly to better sound, that´s a great misconception.
Yes, you are right: it turned out that even with “SNR >95” even 160 watts\4 ohms do not create audible noise at zero music volume.
But my question is different: how can it be that a direct wire without distortion (LA90 with a fantastically low THD) sounds dull and hazy compared to an amplifier with THD <0.03% ???
I've tested at low volumes as well, and at more than 80 dB - and I'm always worse at distinguishing details in high frequencies (cymbal hits, for example. This is Mahler's 3rd symphony at the beginning) when using the LA90.
I don't want to think that my LA90 has become worse in performance (although it has been working for a year+, sometimes 24 hours, and usually 8-10+ hours a day), and I don't want to spend money on testing the LA90D, although it has VERY low dependence of the magnitude of distortion on the signal frequency... But, on the other hand, the 11.11 discount will end in a few hours!!!
Is YBA an honest company or, for example, did they deliberately use some nonlinearities in order to emphasize/make certain parts of the spectrum distinguishable? I ask this because on their website I found a strange text that I did NOT COMPLETELY UNDERSTAND: here
That text is wrong AND confusing.
They are conflating balanced with class B push pull Balanced means you have two opposite signals. A class B design has two amplifiers, of which one only amplifiers the positive signal, and is off during the negative signal, and the other one amplifies only the signal while it is negative and is off while the signal is positive. In that case you may have a distortion (cross-over distort) when the signal crosses the zero point.
Use of XLR is a way to transport the signal, it necessarily balanced. The signal is the difference of hot and cold pins, instead of being relative to ground. This reduces interferences, noise, and also crosstalk between channels. In fact, XLR can be used to carry SE signals.
First of all a good AB design has NO cross over distortion. The circuit needs to be done properly, but this something that has been solved for almost 40 years.
So, I repeat: That text is wrong AND confusing. Since they know how to design amplifiers, there is no way it can be written honestly. They know what they have written and they know it is incorrect.
And, well, they say 0.03% distortion but at which frequency and at which wattage? If you need more power, your actual distortion may be higher. If their circuits are not push pulls, then they may have 2nd order harmonic distortion which, in small amounts, is pleasant. And this may explain your observations.
Finally, since you KNOW that you have slightly increased the volume of the LA90, your brain now can distinguish them blind and apply bias.
Roland68
Major Contributor
Unfortunately you didn't read the title, the text is all about balanced small signal processing in preamplifiers, CD players and so on. And what they write is unfortunately (mostly) true, even if the text is a bit bumpy.
It has nothing to do with power amplifiers and nothing is written about speaker amplifiers in this text.
What they write is the reason why I now use my own boards to convert SE to Balanced and vice versa.
Then what they write is even worse, because they write:
"In balanced, you have one stage taking care of the positive part of the signal and a second stage taking care of the negative and then you add both together to receive or to send to another unit (amplifier, preamplifier). In adding them you create something that nobody wants; it is a cross distortion."
And this is NEVER how a preamplifier or output stage of a CD player/DAC works. In this case they almost always work like two class A circuits 180º out of phase with each other. Exactly like your unbalanced to balanced circuit (if done properly).
Sorry, they are either implementing their stuff wrong, or they are lying.
Roberto
Ricwa
Member
An amplifier with higher distortion can sound more detailed (less dull and hazy) due to the higher amplitude harmonics (distortion). Although the higher distortion amp may sound better over short listening intervals, it can become fatiguing over time.
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You heard no details, just exaggerated highs - distortion exactly what all those 'hi end' amp do.
Hope that helps.
Is there any indirect way to confirm the assumption that distortions have a “positive” effect? For example, I am not only able, but I prefer to turn down the volume of a more expensive (and more powerful - 166 watts per channel) amplifier compared to the volume of the LA90, which begins to sound like a more expensive and more powerful amplifier only at higher volumes. That is, having compared both of them at the same volume, I hear better the more powerful one - but it is perceived as UNNECESSARY loud (and at a much lower volume everything is perfectly audible). And it’s impossible to listen to LA90 at such a starting volume - the music disappears, you need to increase the volume and then small details appear that you can hear in a powerful amplifier even at low volume - but then it becomes too loud, it’s just uncomfortable!
Can you use this information to answer the question - which of these two amplifiers is faulty (after all, the LA90 can also fail after more than a year of continuous daily use for many hours)?
What method can be used to understand what is happening with these two amplifiers?
Just posted my impressions of a more thorough comparison of these two amplifiers. I will add that the more powerful of these amplifiers does NOT tire you out - rather, on the contrary, it makes listening more comfortable, not only because of the ability to listen to quiet music, but also because of the richness of the music (but I can’t say anything about this - I don’t know, Is it interference or the high-quality work of this amplifier - or, conversely, the poor work of MY LA90)
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