Topping LA90 Discrete Amplifier Review

[Gavb1105]

Well I've lost £40 in non-sterling transaction fees but at least I have managed to cancel my pre-order and will now wait to see how this develops. I'm hoping this is a one-off failure and not a wider issue with the amplifier. It will be interesting to see how Topping deal with your return.

 

[Down South]

Requested video: https://streamable.com/r1g77r

I want to reiterate I didn’t join to report this problem, I discussed buying it earlier in this thread and bought it

One thing that is clear from the vid is that your cables are really yanked over - why. It's never a good idea. Cables should follow a relaxed curve - why is the Topping at right angles to the shelving?

 

[aphysically]

One thing that is clear from the vid is that your cables are really yanked over - why. It's never a good idea. Cables should follow a relaxed curve - why is the Topping at right angles to the shelving?

This isn’t where this LA90D was placed during use nor what cable it was used with normally; it was just a spot where I cleared on my desk near the speaker to make the video.

 

[aphysically]

Better keep your speaker far and away from it,disconnect it ASAP,it sounds like something bad is about to happen.

Yeah, only reconnected to make video. Hopefully nothing that would have damaged my KEF already though…….?

I am definitely frustrated. It looks like speaker crackle was one of the reported failure modes in the PA5. The statement from John Yang on ASR was those failures were primarily due to the module used to protect trade secrets. I can see two of the black box modules in the photos of the LA90D opened up that someone posted earlier in this thread. Given that someone on ASR reverse engineered the PA5 black box module to make an open source replacement anyway, I question the wisdom of using it here in the LA90D and would be very disappointed if that’s the component that failed (I DON’T KNOW THAT).

While I would like a replacement, the only thing that would REALLY make me feel better is reassurance from Topping on at minimum the safety of the failure and maybe getting rid of those black box modules (for BOTH of my LA90D) and barring that just a refund on both of them. It kinda sucks since I bought them as a pair that I might only be able to get a refund on one.

 

[LesterNZ]

Wish I didn't have to write this: But my first Topping LA-90 Discrete ( Post #232) has done the dirty on me after just about 1 month.

So, I noticed it's input select #1 light rapidly blinking with nothing playing from Roon-WiimPro-Metrum Amethyst and I went over to the reasonably clear bookshelf placement (free 20 C. air on all sides) where that 'little boy's' chassis was too hot to touch for any more than 2 seconds. ON-OFF button didn't work, then mains power pack cut and then wait to see WTF. Next, my BIG mistake, as a nice little scrap of included paper says "Warranty Void" - if you open it up yourself!

Over-enthusiasm for finding a baked 'Discrete' component had me unscrewing & pulling out the back I/O panel a bit too quickly where I strained (broke) two ribbon chassis connectors to the front panel volume control & input select knob-buttons. Considerable re-seat fiddling with the 'WAY too short' ribbon cables connectors within the five sided outer chassis got me nowhere for finishing proper re-assembly. This was to simply find out if a power re-set cycle was all that was needed, or not. No answer available.

So I've functionally 'Bricked' my analogue component. And it serves me right for stupidly thinking consumer grade components can easily be fixed like real Professional & Broadcast level items that have some accessible sub-assemblies, documentation etc. NOT here, boyo! I can't imagine whatever - caused the LA-90D to over-heat. Though I'm always suspicious of my high-rise apartments' RF environment with 3 nearby lifts, thousands of LED lamps throughout, a huge transmitting (everything) SKY Tower (pure line-of-sight 750M away) and so forth. But I've put soft iron chokes around all inter-connects and carefully earthed whatever-everywhere, and had no problems with my 'perfect' 3 March Audio Purifi-Eigentacts and Kinki M-7 amps & associated gear

Live & learn - the hard way! But at least it's not anywhere near the price of a new car or proper vacation etc. And I console myself with the thought that I've picked up restaurant tabs for nice family dinners etc for greater amounts than this budget-friendly 'tricky' little 'Top Performer'.

 

[Sokel]

Yeah, only reconnected to make video. Hopefully nothing that would have damaged my KEF already though…….?

I am definitely frustrated. It looks like speaker crackle was one of the reported failure modes in the PA5. The statement from John Yang on ASR was those failures were primarily due to the module used to protect trade secrets. I can see two of the black box modules in the photos of the LA90D opened up that someone posted earlier in this thread. Given that someone on ASR reverse engineered the PA5 black box module to make an open source replacement anyway, I question the wisdom of using it here in the LA90D and would be very disappointed if that’s the component that failed (I DON’T KNOW THAT).

While I would like a replacement, the only thing that would REALLY make me feel better is reassurance from Topping on at minimum the safety of the failure and maybe getting rid of those black box modules (for BOTH of my LA90D) and barring that just a refund on both of them. It kinda sucks since I bought them as a pair that I might only be able to get a refund on one.

Topping's explanation about the "black box" failure was due to the the number of op-amps inside it (4 I think) causing thermal issues.
And the fix is supposed to be simply having only two of them each (and no more).

Let's see if our experienced technical members can identify the cause of this by the sound of your video.
For one thing,it sounds ominous,you did good by putting it aside.

 

[Down South]

Wish I didn't have to write this: But my first Topping LA-90 Discrete ( Post #232) has done the dirty on me after just about 1 month.

So, I noticed it's input select #1 light rapidly blinking with nothing playing from Roon-WiimPro-Metrum Amethyst and I went over to the reasonably clear bookshelf placement (free 20 C. air on all sides) where that 'little boy's' chassis was too hot to touch for any more than 2 seconds. ON-OFF button didn't work, then mains power pack cut and then wait to see WTF. Next, my BIG mistake, as a nice little scrap of included paper says "Warranty Void" - if you open it up yourself!

Over-enthusiasm for finding a baked 'Discrete' component had me unscrewing & pulling out the back I/O panel a bit too quickly where I strained (broke) two ribbon chassis connectors to the front panel volume control & input select knob-buttons. Considerable re-seat fiddling with the 'WAY too short' ribbon cables connectors within the five sided outer chassis got me nowhere for finishing proper re-assembly. This was to simply find out if a power re-set cycle was all that was needed, or not. No answer available.

So I've functionally 'Bricked' my analogue component. And it serves me right for stupidly thinking consumer grade components can easily be fixed like real Professional & Broadcast level items that have some accessible sub-assemblies, documentation etc. NOT here, boyo! I can't imagine whatever - caused the LA-90D to over-heat. Though I'm always suspicious of my high-rise apartments' RF environment with 3 nearby lifts, thousands of LED lamps throughout, a huge transmitting (everything) SKY Tower (pure line-of-sight 750M away) and so forth. But I've put soft iron chokes around all inter-connects and carefully earthed whatever-everywhere, and had no problems with my 'perfect' 3 March Audio Purifi-Eigentacts and Kinki M-7 amps & associated gear

Live & learn - the hard way! But at least it's not anywhere near the price of a new car or proper vacation etc. And I console myself with the thought that I've picked up restaurant tabs for nice family dinners etc for greater amounts than this budget-friendly 'tricky' little 'Top Performer'.

It couldn't just be the op-amps inside the black box that made your amp too hot to touch. Part of the problem is the really stupid horizontal heat sinks and that with all these components crammed into a box that is far too small. On page 13 you can see power resistors squeezed between other components - just how are they going to be able to dissipate heat. I had seriously considered buying this model but it does seem that problems are occurring after a some time and that they are heat related. Will Topping withdraw this model and (a) change the stupid horizontal heat sinks for vertical ones, (b) remove the stupid black boxes and (c) use a much bigger chassis allowing the PCB, bottom and top plates to be perforated to create a natural convection current. They could also be using components that are too close to their limits, both resistors and caps.

A sensible company would admit their mistakes and after creating a totally tested new product, replace defective units for free - this is called doing good repeatable business - in business ego isn't worth s~#t, only reality has value.

 

[anphex]

I can't really believe that a company would put a 900 € amplifier directly on the market without testing it for at least a few weeks under extreme conditions to simulate aging. I still hope that this is just survivor bias and 99% of all devices out there work wonderfully.
If not, for me that would mean moving back to Hypex/Purifi.

 

[Sokel]

I can't really believe that a company would put a 900 € amplifier directly on the market without testing it for at least a few weeks under extreme conditions to simulate aging. I still hope that this is just survivor bias and 99% of all devices out there work wonderfully.
If not, for me that would mean moving back to Hypex/Purifi.

Topping LA90 Discrete Amplifier Review

This is a review and detailed measurements of the Topping LA90 Discrete balanced stereo amplifier. It was sent to me by the company and costs US $799. The case is the same as the IC-based Topping LA90 which is fine with me given its high quality look and feel. The power switch doubles as input...

www.audiosciencereview.com

...and it's only couple of months.

 

[Down South]

Topping LA90 Discrete Amplifier Review

This is a review and detailed measurements of the Topping LA90 Discrete balanced stereo amplifier. It was sent to me by the company and costs US $799. The case is the same as the IC-based Topping LA90 which is fine with me given its high quality look and feel. The power switch doubles as input...

www.audiosciencereview.com

...and it's only couple of months.

Agree entirely. I shall check out on the net to see how many other negatives are out there.

 

[Vini darko]

Agree entirely. I shall check out on the net to see how many other negatives are out there.

Yay witch hunt time

 

[Down South]

Yay witch hunt time

What a weird reply.

 

[phoenixdogfan]

I'm thinking this guy could be used as a headphone amp as well. Might be a contemporary update and upgrade on the Schiit Ragnorok.

 

[aphysically]

Really shockingly it seems my other LA90D has just failed. I didn't expect that even if there was a design problem - 2 within a week of each other. Although in the grand scheme of things I haven't had them too many weeks. When I got home from work today symptom was every 10 minutes or so hearing a slight white noise in the left speaker channel only. I reseated everything, removed all inputs, and started outputting the left channel to my right speaker in case the left speaker was damaged by the prior LA90D or something. Right speaker is now showing the same crackle. It's very intermittent so it's going to be hard to get a video, but it seems to be happening more and more often so I'll let it run for just a little and see if I can't grab something. The sound is not the same as the popping from before. The other channel still seems to be working fine (I'm using it in stereo mode now since it's my only remaining LA90D. I never tested stereo mode on the first one that failed and the pop is bad/loud enough that I don't really want to hook it up again.) I suppose I'll get a refund if Topping's recommended Apos retailer works out - they got back to me last night offering a refund on the first so I'm waiting for instructions (I'm still nervous here, though). I really feel bad for Topping, though. I really like my A90D and D90SE - and had liked my LA90Ds before the past week. I hope it was just a bad batch or something.

 

[theREALdotnet]

I really feel bad for Topping, though. I really like my A90D and D90SE - and had liked my LA90Ds before the past week. I hope it was just a bad batch or something.

Let’s hope that “Just a Bad Batch” doesn’t become Topping’s new tagline.

 

[dananski]

That's such a shame. I was getting close to ordering one myself. Thanks @anphex, @aphysically, @LesterNZ for sharing.

Maybe I'll take part in the next round of UAT if Topping can resolve this first wave of problems...

 

[Down South]

And the hits (negative) just keep on coming - by now Topping should have made a company statement about their products, along the lines - we recognize we have a problem and will discontinue sales until the problem/s have been totally resolved.

Would anyone seriously consider buying from this company at the moment - really?

 

[Sokel]

Really shockingly it seems my other LA90D has just failed. I didn't expect that even if there was a design problem - 2 within a week of each other. Although in the grand scheme of things I haven't had them too many weeks. When I got home from work today symptom was every 10 minutes or so hearing a slight white noise in the left speaker channel only. I reseated everything, removed all inputs, and started outputting the left channel to my right speaker in case the left speaker was damaged by the prior LA90D or something. Right speaker is now showing the same crackle. It's very intermittent so it's going to be hard to get a video, but it seems to be happening more and more often so I'll let it run for just a little and see if I can't grab something. The sound is not the same as the popping from before. The other channel still seems to be working fine (I'm using it in stereo mode now since it's my only remaining LA90D. I never tested stereo mode on the first one that failed and the pop is bad/loud enough that I don't really want to hook it up again.) I suppose I'll get a refund if Topping's recommended Apos retailer works out - they got back to me last night offering a refund on the first so I'm waiting for instructions (I'm still nervous here, though). I really feel bad for Topping, though. I really like my A90D and D90SE - and had liked my LA90Ds before the past week. I hope it was just a bad batch or something.

Can you please describe your chain,starting from the AC plugs all the way to your speakers including interconnects?
Music gender preference?

Any other non-audio devices in the room (A/C,led strips,etc)?
I'm not trying to find faults of your own,just curious if something is stressing them (which of course shouldn't,any consumer device should be immune to environment to a sensible extent).

 

[BoredErica]

Just speaking as someone who has no real understanding of how amps are made... Intuitively, the idea that having 4 op amps under a black box is too hot causing significant failures means we should just put 2 instead seems unconvincing and I think other non-techies would think this way too. If instead they say 'no more black box + amazing new heatsink' I'd feel way better. Not that I know this is the issue w/ LA90 ofc.

 

[Down South]

Sokel,
having once used valve gear I know that putting a valve phono stage near a PSU can cause hum problems but the LA90d is housed in a sturdy aluminium case, there should be no interference externally.

aphysically - can you not post on this forum or another for someone with the nec. experience to take a look at your amps, that is the solution. Probably all it will take is a simple continuity check to identify the problem.

So you get the first amp replaced with another, if it's a replica of the first the same problem will occur.