[sajunky]

Neurochrome HPA-1 used 2x SMPS in series. But that is beside the point. This is an L30 thread and nothing to do with the A90, which was predominantly designed to be used balanced.

A small butique developer. Tom Christiansen was forced to add a pair of LM317/337 linear regulators to deal with a problem. Still power supply noise is present on the FFT. It is why, but users did not complain. On the other side A90 is exceptional as Topping decided there was no need for linear regulators - there is absolutely no power supply noise. What we see on the FFT is an analyzer noise (as Amir says). .LOL. However users keep complaining, here is another case from the same forum: https://www.audiosciencereview.com/.../topping-a90-static-issues-help-please.14923/

I agree to one point, it is a time to stop talking about A90, Thank you very much.

It is good that L30 has no such problem. cheaper and so far no defects. That is! I wrote about in my pervious post confirming it. It was my finding, you are only repeating what I wrote already (a parrot speach not quoted).

 

[Muataz]

I mean does Heresey not measure just as cleanly? Not sure if it's putting out 2W tho,

It measures way better for 50mw which will help with IEM. And can gives 3.5Watt

 

[cel4145]

Apos Audio announced yesterday they are taking orders and will ship on the 31st

https://apos.audio/blogs/news/topping-l30-headphone-amp-coming-soon-on-apos-audio

Ordered!

 

[dmac6419]

ASR "established experts" didn't pickup design fault in Topping A90. Also ASR measurements didn't show ground loops introduced by such a fault. It is despite of the fact that ground loops are typically a plaque of Amir's equipment (only when testing non-Topping products like TotalDAC). I bought Topping D30 (featuring the best measurements on ASR) and it produce trash, not a sound.

From my experience ASR measurements are cannot be trusted. Having said the above, L30 doesn't look bad and is worth trying. It doesn't have dual MeanWell SMPS outputs hoocked in series (so is free of A90 fault) and it doesn't cost $500. .LOL.

I expected a price closer to $100, it is a real value of L30.

What have you tested, get real dude,if all you have is a hundred bucks get something for a hundred bucks or save 39 bucks, I have the A90 and ordered the L30 because I could, have had the A90 since day one,nary a problem.

 

[individual6891]

A small butique developer. Tom Christiansen was forced to add a pair of LM317/337 linear regulators to deal with a problem.

Forced you say? Errmm...Where is the LM317/337? He did use it in the older HP-1 amp to regulate to +/-18V (Meanwell don't supply this voltage). Obviously it would also help with ripple rejection, but not solve any of the issues you so mention. So no, he doesn't need to use it. There is no "forcing".

He may be boutique, but you asked the question and I replied accurately. You now have two tested commercial amps using SMPS in series with no issues.

Either you have deluded yourself to the point you can't sense your own inaccuracies, or I smell a troll.... Either way, you can (and should) stop now. Please.

 

[bahamot]

I have put him on my ignored list.

 

[dmac6419]

I have put him on my igmored list.

Sajunky I assume

 

[Makiah S]

Hey guys heads up! Apos is doing a little sale on the L30/E30 Stack, with a pair of Topping RCA Interconnects included

 

[bahamot]

Sajunky I assume

Sure is. Just could not read his/her nonsense anymore.

 

[sajunky]

Forced you say? Errmm...Where is the LM317/337? He did use it in the older HP-1 amp to regulate to +/-18V (Meanwell don't supply this voltage). Obviously it would also help with ripple rejection, but not solve any of the issues you so mention. So no, he doesn't need to use it. There is no "forcing".

Sometimes truth comes unintentionally. You actually wrote that ground loops cannot be removed by adding linear regulators. This is correct. It may reduce, but not eliminate. If you tried, you were a fool. Once you allow multiple path entering the circuit (like it is done in this case), there is no easy way to go away with the problem. A basic design principle is to fight at the source and reduce loop area. A single grounding point is mandatory. There is no single grounding point with two FCC/EU certified SMPS's in series. Get this things right, then you don't have to promote defective designs.

 

[iamwhoiam]

@sajunky - a kind request to stop troubling the thread please. You posted some questionable theory which has been countered. It ought to be over now.

There's now 3x amps using the same power topology and you're still arguing.

Here is a productive suggestion for you: Why not start your own thread and complain to John Yang and Tom Christiansen (@tomchr ) themselves.

....I'm sure they'd be absolutely thrilled.

 

[sajunky]

@sajunky - a kind request to stop troubling the thread please. You posted some questionable theory which has been countered. It ought to be over now.
[...]
Here is a productive suggestion for you: Why not start your own thread and complain to John Yang and Tom Christiansen themselves.

....I'm sure they'd be delighted.

I am not a person who is trying to defend defective design in a wrong thread.

As you have mentioned John Yang, it is unfair to link him to this kind of engineers. He posted a photo of his prototype and there was no power supply. He was using 9V batteries on his desk. Therefore I can't blame John Yang personally, as I am not sure. You make unfolded accusations.

 

[iamwhoiam]

I have put him on my igmored list.

I should have listened to you earlier. . Lesson learnt.

Have had to report more off-topic nuisance, despite my polite request.

 

[dmac6419]

I am not a person who is trying to defend defective design in a wrong thread.

As you have mentioned John Yang, it is unfair to link him to this kind of engineers. He posted a photo of his prototype and there was no power supply. He was using 9V batteries on his desk. Therefore I can't blame John Yang personally, as I am not sure. You make unfolded accusations.

all this knowledge you claim to possess were is your state of the art product?

 

[NA Blur]

Have the E30 2004+ version and L30 amp coming for review and comparison against the D50s and Heresy stack. I'll update early next month ( August 2020 ) and give some impressions / observations.