[Poll] What is your experience with the reliability of the Topping LA90D?

[SashaR]

None.
Hard to find two more identical amps, Topping churns out this stuff one after another. They are technically identical until they break. And to be clear, a defective LA90D will sound odd, reliability is a really big deal.

Yes, I read the opinion of AmirM that the increase of 2 and 3 harmonics in the LA90D is insignificant (although it is 3 dB!) - but I am attracted by his indication that there is NO dependence of the distortion level on frequency in the LA90D - and at the same time the distortion level is lower than that of the LA90! And although I have heard that this improvement is inaudible, I am very impressed with this improvement - although I do not know if it is not equalized by the distortion in 2 and 3 harmonics, increased in the LA90D ?!

 

[dan_uk]

Excuse me for the repeating my question. Can you help me with your answer?
(Besides more power, is there any reason to replace the LA90 with the LA90D?)

I "I have TOPPING's DAC and Amp (D90SE & LA90). I have not an issues for about 14 - 18 months. (I listen at 65-70 dB in stereo configuration with 6 and 4 ohm speakers)"

Excuse me for the repeating my question. Can you help me with your answer?
(Besides more power, is there any reason to replace the LA90 with the LA90D?)

I wasn't commenting on the question, more the fact you made the same statement twice in 2 different posts "I have TOPPING's DAC and Amp (D90SE & LA90). I have not an issues for about 14 - 18 months. (I listen at 65-70 dB in stereo configuration with 6 and 4 ohm speakers)"

 

[SashaR]

None.
Hard to find two more identical amps,

to be clear, a defective LA90D will sound odd,

Could you (or anyone) answer this question? Thank you!

 

[dan_uk]

Could you (or anyone) answer this question? Thank you!

My defective LA90D start to make static-like noises, random unpleasant spikes in the sound, the kind of sound that may damage your speakers.

 

[MAB]

Could you (or anyone) answer this question? Thank you!

Hard to find two more identical amps. Unless one is broken.

 

[SashaR]

Hard to find two more identical amps. Unless one is broken.

Are you talking about their identity based on published measurements or on personal, direct perception? I asked about what is the effect of increasing noise and harmonic distortion and, on the other hand, decreasing distortion - both made in LA90-D? What is the result of these changes from a theoretical / scientific point of view and, on the other hand, how is it actually perceived by those who listened to both of these amplifiers?

 

[MAB]

Are you talking about their identity based on published measurements or on personal, direct perception? I asked about what is the effect of increasing noise and harmonic distortion and, on the other hand, decreasing distortion - both made in LA90-D? What is the result of these changes from a theoretical / scientific point of view and, on the other hand, how is it actually perceived by those who listened to both of these amplifiers?

So so far below human perception.
Go to Klippel and take the the distortion perception test, see for yourself what the audible threshold is for distortion. And avail yourself of other tools to answer your questions about human audibility of distortion. At that point you might realize that these extremely low noise and distortion amps are about as closely matched as can be, differ by distortion SPL equal to about 1 gnat burp. Modern audio analyzers can measure down to that level.

 

[SashaR]

So so far below human perception.
Go to Klippel and take the the distortion perception test, see for yourself what the audible threshold is for distortion. And avail yourself of other tools to answer your questions about human audibility of distortion. At that point you might realize that these extremely low noise and distortion amps are about as closely matched as can be, differ by distortion SPL equal to about 1 gnat burp. Modern audio analyzers can measure down to that level.

Yes, yes, I am aware that analyzers hear better than people. Thank you. But I am also (primarily) interested in the theoretical / “mathematical” answer: how do the distortions at high frequencies of the LA90-D differ from the distortions produced at the same frequencies by the LA90? Does the reduction in distortion achieved in the LA90-D (they DO NOT GROW with increasing frequency) compensate for the increase in SINAD and harmonics (compared to the LA90). I understand about the gnat, but what will audio analyzers say about the DIFFERENCE in the total amount (%?) of distortion and noise in these amplifiers? I was unable to find out the answer to this question from the AMIRM charts. Can anyone answer this?

 

[MAB]

Yes, yes, I am aware that analyzers hear better than people. Thank you. But I am also (primarily) interested in the theoretical / “mathematical” answer: how do the distortions at high frequencies of the LA90-D differ from the distortions produced at the same frequencies by the LA90? Does the reduction in distortion achieved in the LA90-D (they DO NOT GROW with increasing frequency) compensate for the increase in SINAD and harmonics (compared to the LA90). I understand about the gnat, but what will audio analyzers say about the DIFFERENCE in the total amount (%?) of distortion and noise in these amplifiers? I was unable to find out the answer to this question from the AMIRM charts. Can anyone answer this?

I sent you a link to a plug-in that you can test out various distortion component mixes. Problem is, the differences you ask about are way below the typical distortion of a good loudspeaker. The only area I think an amp like this will provide an audible difference is a high efficiency driver, due to the low noise. I noticed the low noise on the Topping amp I bought with a compression driver, but it broke after a week. The good news is there are other low noise amps.

Your question might be better on the LA90 review thread, this is the broken amp thread.

 

[Mr_T]

My defective LA90D start to make static-like noises, random unpleasant spikes in the sound, the kind of sound that may damage your speakers.

I have the same problem. I bought 2 Topping LA90D in mono, after a month of use one amp started to produce clicking sounds like static electricity, high amplitude which can damage the speaker. Returned it to the seller, currently under inspection. Stayed with one amp in stereo. Yesterday it started giving the same signal spikes on one channel. I am very frustrated because I really like the sound of it. Don't know what to do - replace with new ones or look for something else? What other AB class options are there in this price range?

 

[dan_uk]

I have the same problem. I bought 2 Topping LA90D in mono, after a month of use one amp started to produce clicking sounds like static electricity, high amplitude which can damage the speaker. Returned it to the seller, currently under inspection. Stayed with one amp in stereo. Yesterday it started giving the same signal spikes on one channel. I am very frustrated because I really like the sound of it. Don't know what to do - replace with new ones or look for something else? What other AB class options are there in this price range?

Personally, I'd send the item back and get a full refund. The fact they want to 'inspect' it is crazy and so close to your purchase date. What will happen if the problem returns in 11 months or even out of warranty??

I ended up buying a NORD HypeX based amp and am very happy with my purchase. I had decided on HypeX so went with NORD as I'm UK based.

 

[misterdog]

The fact they want to 'inspect' it is crazy

I thought I had a problem with my Topping Pre 90, bleed from one input to the other. Never a problem with my previous preamp. So I automatically blamed the new product after a simple switching inputs test.
On full investigation it transpired I had wired one set of XLR with reverse polarity .
The problem was user error, not a faulty product.

 

[gfinlays]

Hmmmm, I was seriously considering a Topping LA90D for the tweeters in my active system currently under construction. They were mentioned by Karl Lundahl in his response to the VC2361 review as they are used in Lundahl's reference sound system.

Seeing the percentage of users with issues, I'm not so sure. Maybe I'll just save up the extra shekels and add a third AHB2 to the existing pair.

 

[terryforsythe]

Hmmmm, I was seriously considering a Topping LA90D for the tweeters in my active system currently under construction.

A pair of the Topping B100s would save a little bit of money and, based on Amir's reviews, should perform as well if you don't need volume control for your tweeters. But, there still is the question about long term reliability with Topping products.

I have a pair of Topping LA90Ds running my midranges and tweeters in an all active setup (one amp powers the midrange and tweeter in the left speaker, and the other amp does the same for the right speaker). I have been running them since January and no issues thus far. I have a Topping MX5 I have had for well over 2 years. No problems thus far.

 

[gfinlays]

A pair of the Topping B100s would save a little bit of money and, based on Amir's reviews, should perform as well if you don't need volume control for your tweeters. But, there still is the question about long term reliability with Topping products.

I have a pair of Topping LA90Ds running my midranges and tweeters in an all active setup (one amp powers the midrange and tweeter in the left speaker, and the other amp does the same for the right speaker). I have been running them since January and no issues thus far. I have a Topping MX5 I have had for well over 2 years. No problems thus far.

I have a few Topping DACs dotted around the place and a PA5 II. Its predrcessor PA5 went the same way as many others, with the failed potted module.

I'll have a ponder. I don't need volume control - that will be via either a Lundahl VC2361 or an SPL Volume 8.

 

[Tlow98]

I have a few Topping DACs dotted around the place and a PA5 II. Its predrcessor PA5 went the same way as many others, with the failed potted module.

I'll have a ponder. I don't need volume control - that will be via either a Lundahl VC2361 or an SPL Volume 8.

Have you considered the b200s? That’s the one I’ve been pondering purchasing, but given their relation to the LA90D I’d love to know that they’ve worked the kinks out before taking the plunge…

 

[gfinlays]

Have you considered the b200s? That’s the one I’ve been pondering purchasing, but given their relation to the LA90D I’d love to know that they’ve worked the kinks out before taking the plunge…

I did consider the B200s, but given their price, and the previous reliability issues with other models, I bought a pair of Hypex Nilai 500 monos from a UK seller. The modules and PSUs have a 5-year warranty and are easily replaced in the event of any problems. There was also enough space on the rear panels to drill them and fit Neutrik Speakon connectors.

 

[antcollinet]

I did consider the B200s, but given their price, and the previous reliability issues with other models, I bought a pair of Hypex Nilai 500 monos from a UK seller. The modules and PSUs have a 5-year warranty and are easily replaced in the event of any problems. There was also enough space on the rear panels to drill them and fit Neutrik Speakon connectors.

Which UK seller?

 

[Tlow98]

I did consider the B200s, but given their price, and the previous reliability issues with other models, I bought a pair of Hypex Nilai 500 monos from a UK seller. The modules and PSUs have a 5-year warranty and are easily replaced in the event of any problems. There was also enough space on the rear panels to drill them and fit Neutrik Speakon connectors.

Completely understand. Thanks for the follow-up.

I’ve also been contemplating the Hypex-based amps, but I’ve never really listened to a class D based amp on a hi-fi system. Decisions, decisions.

Thanks again, and I’m glad you found a solution that’s working for you!

 

[gfinlays]

Which UK seller?

KJF Audio - https://kjfaudio.com/product/hypex-nilai500diy-500w-mono-kit/

In stock and really fast delivery.

They were really helpful when I asked about drilling the cases for the Neutrik connectors too.