Topping LA90 Review (Integrated Amplifier)

[F1308]

Because the amplifier was already at it's limit.

Thank you very much.
At its limit before reaching all the travel available for the knob ?
I mean, having some 330 degrees to turn, limit is suddenly reached when at 30 or 40 degrees before the end ?

 

[pma]

The LA90 can do 50W in 8 ohm

... 1% distorted heavily clipped with the forest of high order harmonics spread to infinity. Definitely audible! It makes only 2x36W/8ohm of clean power.

 

[solderdude]

So this is more or less a power amp itself. Seems like it would nake more sense to use +/- power supply. But I said I didn't want to judge!

Yes, it is. The circuit used will be more similar to the one I posted.
A Virtual ground basically is a power amp with 1/2 input voltage DC out that can drive large capacitors and source/sink the needed current.

 

[Eneko]

... 1% distorted heavily clipped with the forest of high order harmonics spread to infinity. Definitely audible! It makes only 2x36W/8ohm of clean power.

yep, this is why I tried to do the numbers with 36W, but it will still be able to drive the speakers at at 98.5 dB SPL (LS50 meta, 83dB SPL, for clarification)... So, well above the limit of what the speaker can tolerate...

 

[ROOSKIE]

Thank you for the answer but I don't think that I am understanding it, if the speaker can't handle anything above 86dB SPL (1m) without falling apart... why would you want an amp able to drive it further (and this will do it at >98dB SPL)?

the speaker is not falling apart at 86d@1m.
Don't mistake the HD graph for that.
It is not a bass monster nor a super high volume speaker due the small 5" driver but HD distortion is not what you think and you will likely be able listen at those volumes without really noticing it to much.
Especially on peaks. It will need power.
Plus what if you High Pass to subs?
Anyway I can only say it is deff not enough power for me.
You will be the one who knows the size of your listening space and how loudly you want to play with clean power on tap.
This amp does not have enough power IMHO especially for a low sensitivity speaker. Now a 89db sensible speaker vs 83 makes this into effectively 4 times more powerful unit, so that could work for most cases though I'd still want more.
(In the nearfield this is plenty of power even with an 83db sensitive speaker so desktops could deff use this.)
Again don't underestimate how much that 3.7ohm midbass and midrange will draw, midbass has tons of energy in many recording, tons.
If you ever listen at higher volumes in farfield with the Meta or similar speaker this amp will give you very unclean and clipped power often.

 

[solderdude]

... 1% distorted heavily clipped with the forest of high order harmonics spread to infinity. Definitely audible! It makes only 2x36W/8ohm of clean power.

Power amps are usually rated at 1%.
Topping specs: 2x 50W @ 8Ω THD+N < 1%
36W vs 50W is 1.4dB !!
At 45W distortion is an inaudible 0.03% and at 40W 0.001%.
And near clipping peaks of 1% in music aren't a terribly audible thing. 10% (2x 63W) is indeed getting audible.

 

[pma]

Power amps are usually rated at 1%.
Topping specs: 2x 50W @ 8Ω THD+N < 1%
36W s 50W is 1.4dB !!
And near clipping peaks of 1% in music aren't a terribly audible thing. 10% (2x 63W) is indeed getting audible.

Thank you, I am able to calculate dB's quite well . Amps are rated at 1% but there are huge differences in audibility of the 1% distortion (again, I hate the single numbers!). Tube distortion of 1% or simple Pass classA 1% is barely audible as it has prevailing 2nd and 3rd order harmonics and with music it will be inaudible in a DBT test to anyone. On the contrary, the 1% distortion created by sharp break of THD+N plot created by high FB solid state amplifiers is perfectly audible. It makes sense to take into account the break-point of the distortion plot. I am sure you know that.

And - this LA90 amplifier is a low power amplifier regardless what anyone is saying. It will be easy to put it into audible clipping in a larger room when classical music with high dynamics is used. I know it very well because I have built several amplifiers of similar power and tested it in many listening sessions. This amp will be OK as a desktop amp, as many will use it like.

 

[TheBatsEar]

Thank you for the answer but I don't think that I am understanding it, if the speaker can't handle anything above 86dB SPL (1m) without falling apart... why would you want an amp able to drive it further (and this will do it at >98dB SPL)?

They might handle a bit more, but it will not sound pretty, it's only a 13cm woofer after all.
This amp should do the deed fine.
And with the lowest THD+N in the forum.

Plus what if you High Pass to subs?

Well, in that case you would send everything below 120 or 150Hz to a pair of subs and the small LS50 and the LA90 don't have to bother with it.
Not sure you gain much more dB however, the LS50 is really not the right speaker if you want dance hall volumes into big areas.

 

[pjug]

Thank you, I am able to calculate dB's quite well . Amps are rated at 1% but there are huge differences in audibility of the 1% distortion (again, I hate the single numbers!). Tube distortion of 1% or simple Pass classA 1% is barely audible as it has prevailing 2nd and 3rd order harmonics and with music it will be inaudible in a DBT test to anyone. On the contrary, the 1% distortion created by sharp break of THD+N plot created by high FB solid state amplifiers is perfectly audible. It makes sense to take into account the break-point of the distortion plot. I am sure you know that.

And - this LA90 amplifier is a low power amplifier regardless what anyone is saying. It will be easy to put it into audible clipping in a larger room when classical music with high dynamics is used. I know it very well because I have built several amplifiers of similar power and tested it in many listening sessions. This amp will be OK as a desktop amp, as many will use it like.

There's nothing wrong with a low power amplifier. You just hope that customers are aware of what they really need for their own use. That can be really tough to determine also, e.g. do I need my amp to handle music with 30dB crest factor when 99% of what I listen to is nothing like that? My preference is to go with overkill on amp power so as to not worry, but I understand others may feel differently.

 

[Eneko]

Thank you, I am able to calculate dB's quite well . Amps are rated at 1% but there are huge differences in audibility of the 1% distortion (again, I hate the single numbers!). Tube distortion of 1% or simple Pass classA 1% is barely audible as it has prevailing 2nd and 3rd order harmonics and with music it will be inaudible in a DBT test to anyone. On the contrary, the 1% distortion created by sharp break of THD+N plot created by high FB solid state amplifiers is perfectly audible. It makes sense to take into account the break-point of the distortion plot. I am sure you know that.

And - this LA90 amplifier is a low power amplifier regardless what anyone is saying. It will be easy to put it into audible clipping in a larger room when classical music with high dynamics is used. I know it very well because I have built several amplifiers of similar power and tested it in many listening sessions. This amp will be OK as a desktop amp, as many will use it like.

Sorry, but I think it is contradictory... 1% distortion is around 40dB, no? the speakers itself will have higher distortion (<600Hz) when the amp puts it at 96 dB SPL (and the amp will be able to put it to 98.5 before it clips itself), so... the sound will not be good anyway... but not because of the amp (if I am getting it right). Sorry for the insistence, I am trying to understand the amp + speakers as a system.

 

[TheBatsEar]

Power amps are usually rated at 1%.
Topping specs: 2x 50W @ 8Ω THD+N < 1%
36W vs 50W is 1.4dB !!
At 45W distortion is an inaudible 0.03% and at 40W 0.001%.
And near clipping peaks of 1% in music aren't a terribly audible thing. 10% (2x 63W) is indeed getting audible.

Isn't that 2x 50W @ 8Ω THD+N < 1% continious? Real Music should be more like short bursts?
I bet you would get better numbers if you gave the capacitors in the power supply time to fetch some more juice.

Is this something we can guess from Amirs measurements?

 

[solderdude]

It is an integrated amp and not a high power amp.
Eneko wanted to know if the LS50 could be used with this amp.
It falls in the 40-100W criteria and with 8ohm (3.5 ohm lowest) can be driven with it.
Yes, it won't be playing very loud in a large room but a 100W won't either.
You cannot (and should not) play loud music while having a party.

Hard clipping SS is unpleasant but it really doesn't matter if this occurs at 36W, 40W or 50W.

 

[solderdude]

Isn't that 2x 50W @ 8Ω THD+N < 1% continious? Real Music should be more like short bursts?

This amp (having a stabilized power supply voltage) has the same 'music/burst' and continuous power.

 

[aravena562]

Thank you, I am able to calculate dB's quite well . Amps are rated at 1% but there are huge differences in audibility of the 1% distortion (again, I hate the single numbers!). Tube distortion of 1% or simple Pass classA 1% is barely audible as it has prevailing 2nd and 3rd order harmonics and with music it will be inaudible in a DBT test to anyone. On the contrary, the 1% distortion created by sharp break of THD+N plot created by high FB solid state amplifiers is perfectly audible. It makes sense to take into account the break-point of the distortion plot. I am sure you know that.

And - this LA90 amplifier is a low power amplifier regardless what anyone is saying. It will be easy to put it into audible clipping in a larger room when classical music with high dynamics is used. I know it very well because I have built several amplifiers of similar power and tested it in many listening sessions. This amp will be OK as a desktop amp, as many will use it like.

It is completely true that it is a low power amplifier, but if you use two bridged ones you have enough power for any normal speaker and cleaner and cheaper than a single ahb2.

 

[TheBatsEar]

Can someone please delete this thread?
Problem is, i bought so much stuff already this year.

I can't stand eating oat porridge with water and artificial sweetener for much longer!

 

[ROOSKIE]

They might handle a bit more, but it will not sound pretty, it's only a 13cm woofer after all.
This amp should do the deed fine.
And with the lowest THD+N in the forum.


Well, in that case you would send everything below 120 or 150Hz to a pair of subs and the small LS50 and the LA90 don't have to bother with it.
Not sure you gain much more dB however, the LS50 is really not the right speaker if you want dance hall volumes into big areas.

The meta is perfectly capable of reasonably satisfying 86db average listening SPL from a 10-12foot listening distance which requires approx 96db at 1meter output. You do get to calculate using 2 speakers and some room gain.
You then factor in higher SPL peaks.
You factor in listen style and every 3db is double the power so it go fast as music gets louder. Does the user plan to go loud?
I listen often (a couple times a week)at near 90 averages with 100db peaks.(the meta or similar system can't do this well without a HP to subs)
Even when crossing to subs the monitors produce most of the energy in the 100-330hrz range which can contain enormous energy.
In the case of the Meta this is the range requiring the most robust amp, not the range below 100hrz.

Sorry, but I think it is contradictory... 1% distortion is around 40dB, no? the speakers itself will have higher distortion (<600Hz) when the amp puts it at 96 dB SPL (and the amp will be able to put it to 98.5 before it clips itself), so... the sound will not be good anyway... but not because of the amp (if I am getting it right). Sorry for the insistence, I am trying to understand the amp + speakers as a system.

Clipping and amp distortion don't work that way.
1% is not a stopping point. It will often be hitting 10% or more across potentially the whole spectrum.
The different between 1% and 10% is likely only 1.5db from that amp. You have no way to stop it at the SPL that is 1%, and since the distortion rises very quickly at that point it will do so. So if listening fairly loudly a peak asks for power you could be looking at 10-50% distortion from the amp, especially at 3.7ohms where the amp is a bit less efficient.(it does not double into 4ohms)

HD 2nd and 3rd order distortion in the bass range from the Meta is likely less noticeable than the amp at 10% spraying distortion across many frequencies and harmonics.

That said you may not even notice that 10% hard clipping but then why buy a well engineered but underpowered (for low sensitivity and/or farfield) $800 amp when a $129 Monoprice 605030 would likely sound just as clean if not better at times? Makes no sense.
It is true we can not hear much of the issues but why pay extra?

 

[TheBatsEar]

Can someone please delete this thread?
Problem is, i bought so much stuff already this year.

Never mind, Audiophonics is out of stock for now. No impulse buy for me.

 

[pma]

if you use two bridged ones you have enough power for any normal speaker and cleaner and cheaper than a single ahb2.

Better not to comment. Output current capability??

 

[ATAineri]

Which speaker do you own that drops impedance to 1 ohm. And when you have then the LA90 should not be on your list.

The specs clearly state ≥ 4 ohm in stereo mode and ≥ 8 ohm in bridged mode.
That excludes >1 ohm and >2 ohm.

When your speaker is that low impedance look for another amp.

If I understand correctly - each acoustic's impedance drop while playback. I want to use pair of this amplifiers with my Heco Clear Revolution 9. My friend has similar acoustic and he wants this amplifiers too in mono mode. Heco says that it has 4-8 ohm impedance and I hope it is appropriate amplifiers for this application. Now I has Emotive HC-1 but I'm not satisfied with its detalization.

 

[ROOSKIE]

It is completely true that it is a low power amplifier, but if you use two bridged ones you have enough power for any normal speaker and cleaner and cheaper than a single ahb2.

While I appreciate the great engineering here to get very low distortion, I still don't think that is enough power.
95watts at 8ohms and 200ish @4ohms and while performing just fine but actually not rated for such loads.
Not super impressed for $1600.
Again I listen loudly frequently so your MMV.
For $1600 2channel, I personally want 300-500 per channel and manufacturer rated down to 2ohm loads which I think is about the true maximum I will ever need for non subwoofer use with a variety of passive speakers at high volumes and loads. Especially with all the great sounding but low sensitivity stuff coming out.

Even some active driver systems need that much power to accommodate things like bass boost. I am making a 2 way right now with a low sensitivity high output 7" woofer. It will be in a sealed enclosure and use 5db of boost at 50hrz. Because of the boost, at high volumes that it can truly handle it needs about 300 watts for the woofer at higher SPL at farfield distances, maybe even more power on certain types of peaks. (and about only 5-10 to the tweeter)

Hopefully for folks like me Topping or someone can follow this with more power and similar or nearly similar overall performance and price.