Topping LA90 Review (Integrated Amplifier)

[Aaron7]

I knew and I did compare the two. The point is, the ATI's THD is already below the threshold of audibility. You need another reason to explain why you heard such an obvious difference, or it could just be Placebo, but most likely its the way to set up the comparison, that may not be an apples to apples one.

You are making an assumption that what you do not hear does not affect the music you are listening to.
If on your room calibration software you cut off all frequencies above 17K, It will sound different than if you let it go all the way to 20k. This is despite the fact that you can not hear anything above 17K. It is because those frequencies do affect the total sound. Hence noises at levels you do not hear do effect the frequencies and music you are listening to.

 

[mike70]

You are making an assumption that what you do not hear does not affect the music you are listening to.
If on your room calibration software you cut off all frequencies above 17K, It will sound different than if you let it go all the way to 20k. This is despite the fact that you can not hear anything above 17K. It is because those frequencies do affect the total sound. Hence noises at levels you do not hear do effect the frequencies and music you are listening to.

It is ok @Aaron7 ... we can theorize anything ... but we are trying to "find" if the difference is real.
why? because science says that our senses are easily cheated.

In a subjective forum, your words will not be discussed at all ... but, here we try to search for the truth, coming from what i mentioned, our brain play games with our senses.

that is all. obviously, you are free to try it or not, but also obviously, if we do not have the real arguments ... your words ... are words.

 

[peng]

You are making an assumption that what you do not hear does not affect the music you are listening to.
If on your room calibration software you cut off all frequencies above 17K, It will sound different than if you let it go all the way to 20k. This is despite the fact that you can not hear anything above 17K. It is because those frequencies do affect the total sound. Hence noises at levels you do not hear do effect the frequencies and music you are listening to.

I made no such kind of general statement. However, you can try turning the master volume of the preamp you are using to minimum and hear what you can hear. I bet you will hear just noise if your ears are close enough to the speakers.

To be clear, I am not saying there will be no audible difference between those two amps but if the difference is as big as you described then the cause will be something else other than the THD difference shown in the ASR measurements, that's all.

 

[Rottmannash]

The difference between the Emotiva monobloc (class D-@Amir measured/reviewed) and the VTV Purifi was clear to me as well. There was an audible harshness on higher frequencies with the Emo vs the Purifi (the Emo-which was worse at higher volumes). The graphs reflect this.

 

[raest]

I always found well made cables to have only subtle differences at best. This would be hard to pass a double blind test.

It is a completely different story from comparing one amp that is clean down to -120 db to one that adds superfluous noises under -99db. When you add alot of noises under -99db it requires the drivers try and reproduce the music together with all these noises simultaneously. There is a 21db of differences of noise. It can shift the tonal balance and makes the drivers work harder trying to reproduce all those frequncies.

your sarcasm detector is broken. there are NO subtle difference with cables. well made or otherwise.

and as Tony has already said, that's not how that works

you're hearing what you're wanting to hear

if the difference were truly night and day, it should be easily measured and detected with a UMIK or equivalent (and most, if not all, attempts so far have failed to confirm these "night and day" differences). which you should already have if you're on this site, because everyone knows (or should know) that room correction >>>...>>> amp, when it comes to audible changes

 

[Aaron7]

your sarcasm detector is broken. there are NO subtle difference with cables. well made or otherwise.

and as Tony has already said, that's not how that works

you're hearing what you're wanting to hear

if the difference were truly night and day, it should be easily measured and detected with a UMIK or equivalent (and most, if not all, attempts so far have failed to confirm these "night and day" differences). which you should already have if you're on this site, because everyone knows (or should know) that room correction >>>...>>> amp, when it comes to audible changes

No sarcasm was meant. In regards to cables, I mentioned that it would have a hard time passing a blind test.
With regard to the amps that have a difference in measurable noise of 21`db well that is measurable!

 

[xaxxon]

I just confirmed directly with Topping that in Bridged mode you need to use speakers with NOMINAL LOAD OF => 8 OHMS. That is great news since most speakers are rated at nominal 8 ohms. I felt the need to check with them since their poor wording online may lead one to think you need a speaker that at any given frequency NEVER dips below 8 ohms as opposed to one that is simply is rated at a nominal 8 ohms.

Of my main speakers I use I have 1 pair (b&w) that are rated 8 ohm, 1 pair (elac) that are rated 6 ohm, and 5 speakers (wilson) that are rated 4 ohm.

 

[antcollinet]

... and 20 years old without tinnitus

Exactly

 

[poxymoron]

No sarcasm was meant. In regards to cables, I mentioned that it would have a hard time passing a blind test.
With regard to the amps that have a difference in measurable noise of 21`db well that is measurable!

Measurable is one thing, audible is another thing entirely. @Aaron7 , I'm calling you out on this one I'm afraid, and I tell you what you're saying is nonsense. No offence.

 

[antcollinet]

Where, in an anechoic chamber with 0 dB SPL background noise?

Strict limits from here.

Audibility thresholds of amp and DAC measurements

Introduction A recurring theme on ASR is whether or not the various measured qualities of the devices are audible. In this post, I'll present some clear and visual thresholds for when those imperfections can be considered a potentially audible concern. I will not explain the basics of amp/DAC...

www.audiosciencereview.com

But yes - 0dB (or close) background noise I would expect. And probably belonging to genus Canis. Hence my statement

30dB noise in the room would be pretty quiet, but would swamp -115dB of Sinad.

 

[Aaron7]

Exactly

Between the ATI and LA90 there is 21db difference in noise levels. That is huge!

 

[antcollinet]

Between the ATI and LA90 there is 21db difference in noise levels. That is huge!

Yes it is huge - but is it audible? If the ATI noise level is already inaudible in real world listening conditions then that 20dB brings no real benefit.

And the ATI has a noise floor roughly equivalent to CD. Can you hear the noise floor on a CD at normal listening levels?

 

[mike70]

I read that Amir recommends to use the "SINAD scale" by the colors in real life ... green, yellow and red.

The "oscilloscope measurement" must be interpreted rightly, in other way .... one of 5 five people in the world are Chinese but in my neighborhood I don't see any Chinese people.

 

[Sokel]

Between the ATI and LA90 there is 21db difference in noise levels. That is huge!

I you ever bother to take the test I posted earlier in the thread you will find hard to hear distortion even up to -65db,let alone -99 or -120.
Don't confuse the right engineering indicators with audible performance.

 

[pepie34]

I have a D90SE linked to my LA90. It seems that the DAC output is quite low comparing to other sources (like my phono preamp, a S3B project which works very well with the LA90).

The D90SE let me choose between a peak level at 4V (default) or 5V at 0db.
Should I change to 5V without damaging my LA90 ? I'm only risking sound clipping or it can physically damage the amp ?
I noticed that 4V is the standard for XLR balanced line level.

 

[Aaron7]

I have a D90SE linked to my LA90. It seems that the DAC output is quite low comparing to other sources (like my phono preamp, a S3B project which works very well with the LA90).

The D90SE let me choose between a peak level at 4V (default) or 5V at 0db.
Should I change to 5V without damaging my LA90 ? I'm only risking sound clipping or it can physically damage the amp ?
I noticed that 4V is the standard for XLR balanced line level.

I use it with Marantz 8805. I have to boost the Marantz by 3.5db. I use the low gain setting on the LA90. I have had no issue doing that. Although I do not know for sure, logically I cannot imagine 1V destroying the Amp.

 

[DrDen]

I have a D90SE linked to my LA90. It seems that the DAC output is quite low comparing to other sources (like my phono preamp, a S3B project which works very well with the LA90).

The D90SE let me choose between a peak level at 4V (default) or 5V at 0db.
Should I change to 5V without damaging my LA90 ? I'm only risking sound clipping or it can physically damage the amp ?
I noticed that 4V is the standard for XLR balanced line level.

L90 input sensitivity is 6,9V (low gain), so 5V is okay.

 

[DrDen]

L90 input sensitivity is 6,9V (low gain), so 5V is okay.

I mean LA90. My DAC has 5V XLR output (X26Pro).

 

[pepie34]

L90 input sensitivity is 6,9V (low gain), so 5V is okay.

according to the doc it is 2.2V in High Gain which is ridiculously low for balanced XLR no ?

 

[staticV3]

according to the doc it is 2.2V in High Gain which is ridiculously low for balanced XLR no ?

That's with the volume knob bypassed btw.
If you turn down the volume some on the Amp, then you can input 4Vrms in high gain without issues.