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antcollinet

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I don't see class d reliability as something special. Our issues mainly was due to potting. But there must be solutions, because power supply units have using it for ages without issues. It's just that we have to make the testing before production a couple of notch more hardcore.
Stop potting. Based on my 35 years experience in electronics it is difficult to make it work properly without causing quality issues. It is also a nightmare for the factory processes.

And it brings you no benefits - only costs you reliability!

I think your stated reason was to stop your competitors reverse engineering your designs. It won't. One person (on his own) has managed to reverse engineer the PA5 module to enable people to repair their own amplifiers.

I won't add what I think about toppings CS that made that necessary.
 

AdamG

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Hi, John I recently bought a topping A70 pro and I keep getting a HP DC abnormal output error. I ordered from Hifigo, and it was delivered less than 6 days ago. They are asking that I ship the unit back to them?

A forum donar recomended that I ask you here before I send it back. This is what he said:

"Totally unacceptable. Topping should send you an amp immediately, especially for a $500 amp. And paying for shipping back on their broken stuff (the good companies offer a prepaid label) ???

I'e had 3 Topping amps go POP! I no longer desire to be a beta tester for their amps and don't buy.

I would ask John "

The original thread is here. https://audiosciencereview.com/foru...g-a70-pro-hp-preamp-review.44636/post-1644479

I have contacted Hifigo and Topping. Hifigo has got back to me ask that I ship it back at my expense, topping hasn't got back to me, unfortunately.
Taken directly from hifigo’s website:

Warranty & Refund Policy​

7-Day DOA Product Guarantee

You will enjoy this guarantee if you receive a damaged, wrong or unusable item. Please contact us within 7 days of receiving the package for a return authorization.
Once the product has been returned to our designated address, we can ship you a new item for free (we will refund the shipping cost of your return), or you can opt for a full refund.

30-Days No Condition Returns

If you are not satisfied with your purchase and the product is still in brand-new condition, we can arrange a partial refund which will include the item price minus shipping costs. You will be responsible for paying the shipping costs and customs duty for returning your item.
If it is plastic sealed when you get it, it should remain plastic sealed. Some types of goods such as CIEMs and custom cables cannot be returned.
Please contact us within 30 days of receiving your order for a return authorization




Another option is to investigate if the Credit Card you used offers any product replacement/refund policies. Many do offer these perks and people don’t know about them. You said the item failed inside 6 days of receipt. That’s inside the very tight limits of Hifigo’s own policy above. After this experience I would never buy another product from them. If you have problems with Hifigo. Call your credit card company and have them cancel the charge and ship the defective product back to them.
 
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ampguy

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Oh this is a huge topic. I'll try to make it concise.
Firstly it kinda depends on the price range.
But apart from that, current favorite overear is still the Susvara(and one named Nan-NB but that one is not on sale). There are also ones that I enjoy in day to day use. Koss 95x is also quite good, super comfortable and non-tiring sound. Takstar pro82, although not liked by Amir, it's the most close to speaker sounding headphones under 400 dollars. I also like Ananda, very enjoyable sound with huge sound stage. Beyer's dt900prox probably has the flattest bass in all dynamic headphones and overall tonality is pretty good.
In terms of IEMs, I still like Moondrop Kato's sound quite a lot albeit the housing touches a part of the ear that becomes painful after 10 minutes. Truthear is very popular now but I am not that impressed by the zero:red even less so with the original zero. Hexa is ok with foam tips, pretty enjoyable sound but I prefer the comparable Tanchjim Darling. Sennheiser Ie200 is an interesting IEM that deserves a listen. My favorite is probably still the good old er4s with tri-flange or er4b with tsx100 tips.
I've been playing around with speakers recently. Kef Q150 is definitely much better than it seems on measurements, a giant killer even. Super clean from mid to high. No roughness in the sound. Super imaging. The tip here is to forget about toe-in. Can't really find any downsides besides the bass don't go deep. But I'm also the few R3 enjoyers so... Apart from two pairs of kef R3s, I have wharfedale linton, diamond 12.2, elac dbr62, JBL Arena 130(extremely good for the price). I like Q150 almost more than R3.
Same here, I had the Q150s on a dresser for years and they were fine, but not outstanding. I moved them to a different room on proper 24” stands and they came alive. I recommend them often, they occasionally go for sale for $300 a pair.
 

Mnyb

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I'm simply going to tell you what's my personal priority at the moment. This is a modestly-priced, relatively simple AV pre/processor to replace my aging AVR receiver; (to work with a separate downstream multi-channel amp or amps). Currently available pre/pros are (a) over-priced and/or (b) poorly preforming.
I concur decently performing AVP’s are simply unicorns it would be a game changer even you used it for only 2 channels, you get a digital preamp with room correction and subwoofer xover .

Sound quality of a DAC is a solved problem, the DAC should be commodity used inside more interesting products.

If you can’t handle the hdmi/Dolby/dts licensing mess .

Some kind of 2 channel preamp with both digital and analog inputs and DSP and subwoofer integration would be very interesting.

I would not hold my breath, it’s an massive software undertaking in a business where it’s the norm to have shoddy and buggy software.
But one can always hope :)
 

MAB

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Stop potting. Based on my 35 years experience in electronics it is difficult to make it work properly without causing quality issues. It is also a nightmare for the factory processes.

And it brings you no benefits - only costs you reliability!

I think your stated reason was to stop your competitors reverse engineering your designs. It won't. One person (on his own) has managed to reverse engineer the PA5 module to enable people to repair their own amplifiers.

I won't add what I think about toppings CS that made that necessary.
Thanks for saying this, so true.
Examples:
When encapsulating, if there is any manufacturing residue (like solder flux), the encapsulation will typically cause the residue to be an early time to fail.
Also, if there are any electromechanical marginalities in the manufacturing (like bad solder process), encapsulation will typically accelerate/exacerbate the fail. This will show up in early life fails.
Even if the manufacturing process is flawless, encapsulation puts additional thermal and mechanical stress reducing the useful life time. If the manufacturing flow leaves behind stuff like solder flux, then add chemical degradation and new sources of gasses and defects and other insidious mechanisms to degrade your product.

Things get 'potted' for various reasons.

@JohnYang1997 mentioned power supplies... High Voltage power supplies are potted or encapsulated in dielectric materials that prevent a range of behavior, but those materials are often gel or even liquid. And most of the encapsulated devices aren't a bunch of surface mount parts stuffed onto a board. And some HV encapsulations are designed to improve thermals, not degrade.

Other things get encapsulated for environmental reasons, like when seawater or corrosive stuff is the main enemy. In this case, encapsulation makes sense even though the encapsulated component is going to cost much more and almost assuredly will have a shorter maximum service life compared to an equivalent component that is not encapsulated. Of course, the non-encapsulated component fails quickly in the corrosive environment, but it almost always pays a penalty in maximum lifetime. And of course costs much more. And many of these manufacturers have a pre-production model of the encapsulation, and test that model prior to production qualification, and plan on making changes prior to production release, and even include test structures to monitor fail modes in that pre-production reliability run.

Topping @JohnYang1997 appears to be doing the encapsulation for IP. I understand the reasons, and am a bit heartbroken. But to be serious, any competitor can de-lid your encapsulation and reverse engineer in a few hours (@gamerpaddy did just for fun;)). So you don't protect yourself one bit, sorry to say. And you pass reliability onto the customer, double-sorry to say... And I see you are even trying to do some extended life testing to figure out what is going on, which is commendable. If you feel you have a handle on the interaction of the manufactured component with the encapsulation, fine. But even a change in vendor of potting compound, or change in board design, or change in board manufacturing process, or a tool or process running out of spec... all will introduce customer returns... where a non-encapsulated device would be fine.

I have some pain on this. I was one of the early PA5 buyers. I also bought a D30Pro and A30Pro. Sadly, the PA5 succumbed to the defect. I had a very bad experience with one of the resellers, I think you helped get that resolved, and I appreciate. I also had the A30Pro go bad, and I think you may have directly or indirectly helped since the reseller refunded my money after first dragging me out... Much of my frustration is with the resellers so thanks for your recommendation. But, for sure some of it is with the intrinsically unreliable PA5.

In summary:
I would ditch the potting.
I would enforce discipline on the resellers since they play a role in your Brand.
 
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unravel8628

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Hello @JohnYang1997 I want to ask about la90d pop noise issue.
I bought 2 la90d for mono setup one of it starts making noise yesterday.I really worried about another one.
I saw not only my la90d has this issue.
Do you have any technical explain for it.
A little bit disappointing for topping quality control when I get a broken jump wire in la90d package and the la90d also broken.
 
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Billy Budapest

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Does Topping have any plans to produce a true power amplifier (instead of an integrated amp)—one without a volume control or source selector? If they could be removed from a version of the LA90 so that it would cost less to make, that product would probably be a big seller.
@JohnYang1997 Thanks for confirming that! Very exciting news. Just two more questions: 1). Will it have more power (for example, by containing two bridged LA90 units); 2). Will it include an internal power supply?

If so, this new amplifier would offer serious competition to Benchmark, Purifi, and Hypex amplifiers. (The LA90 already offers serious competition in terms of measured performance but it doesn’t really appeal to consumers who want or need the higher power ratings of the Benchmark, Purifi, and Hypex units).

Thanks again and keep up the great work. You are one of the top minds in audio engineering today.
 

kipman725

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The KX drivers for the soundblaster Audigy allowed access to the internal DSP for stuff like crossovers, PEQ etc. There isn't much anything like it today apart from dedicated standalone DSPs like those from Symetrix and QSC, also some DIY software based solutions but this has latency implications. Some kind of 'free form' DSP inside an audio interface would be cool, the BOM cost would not be huge as all that would be required would be small FPGA or DSP; however the software development would be considerable.
 

Gorgonzola

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I concur decently performing AVP’s are simply unicorns it would be a game changer even you used it for only 2 channels, you get a digital preamp with room correction and subwoofer xover .

Sound quality of a DAC is a solved problem, the DAC should be commodity used inside more interesting products.

If you can’t handle the hdmi/Dolby/dts licensing mess .

Some kind of 2 channel preamp with both digital and analog inputs and DSP and subwoofer integration would be very interesting.

I would not hold my breath, it’s an massive software undertaking in a business where it’s the norm to have shoddy and buggy software.
But one can always hope :)
The 2.1 channel preamp you're describing, @Mnyb, would be a welcome thing and significant functional upgrade over the Pre90. I agree that 2.1 channels, i.e. including a subwoofer(s) crossover, would be highly desirable, (of course there are competitive products that have the feature).

DSP would be great too, but Dirac, Audyssey, or similar 3rd party product would be a licensing issue. For Topping to develop its own, in-house DSP likely be too much to ask.

In any case the above would be no serious alternative to a true AVP which device must, necessarily, handle HDMI I/O and at least 5.1 channel Dolby and DTS decoding. Preferable, it not essential, would have differential, balance audio outputs.
 

192kbps

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1, I'm not sure.
2, I don't understand what you mean. There are regional resellers that do very good job. Namely, Apos, audiophonics, Addicted to audio.
3, Not in the sense of the likes of e1da. Competitive yes, sota no.
I think it refers to the problem that the input impedance of your equipment is too low.
 

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Sokel

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What will be a significant upgrade is a pre with the points noted above which can also mix and match unbalanced and balanced I/O (like the Gustard if I remember well) so we can rest the gazzilion threads who ask how to do it properly.
Full size of course,not desktop.
 

Sokel

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I think it refers to the problem that the input impedance of your equipment is too low.
I think he got that,he's just not sure if they will do it (that's what I understood by the answer) .
 

Plcamp

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The one thing I like most about google chromecast with live tv is that the use of HDMI allows on/off and volume control of the attached device via ARC.

A tv dedicated ‘ARC DAC’ would not add another remote.

I suppose the market for this might be too small?
 

Cool Runnings

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Anything related. I answer them as much as I can.
Thanks for being accessible. Very rare. Well done.

I am using E70V with PA7+ with JBL A120 speakers with sub in bedroom. Very happy with the sound.

My question is whether I can improve sound quality further by using the E70V in DAC mode only. I read somewhere that this improves SQ for DSD music playing. But I was wondering if it'll work also for normal TIDAL PCM quality streaming.
 

threni

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Anything related. I answer them as much as I can.
All I'd ask/say is:
As a really happy E30 owner (had it for years, use it every day) I have no problem with Topping stuff, and would consider them for future purchases, but there've been quite a few serious issues with (especially) amps/dacs failing which seem to be both design and build quality related. Most people are buying the kit thousands of miles from China so returning it is a faff/expensive, and that's if you can get the retailer to honour their legal requirements regarding returns/refunds etc, so it's not like you can rock up at a local shop and swap it for a replacement at your convenience.
Questions:
Are you aware of how much your reputation has fallen on ASR in the last year (this site - and especially its owner - was accused of being Topping shills such was the great performance measured on your devices)?
Do you have a good understanding of the various problems?
Are you - and can we - be sure this sort of thing really won't happen again? (Obviously this can't be a 100% promise but someof these problems happened to Schiit and they upped their game and you don't hear about it happening to their stuff any more).
Any plans to address the after-sales lucky dip?
 

IAtaman

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Perhaps. I had an RME ADI-2 DAC FS for a time. I found the onboard EQ to be effective, but a pain to set up and adjust due to the tiny screen, sub-menus, etc. I’m not sure if there are competing products with better ergonomics, but the RME failed in this regard.

On the music production side Sonarworks is pretty ubiquitous. It’s dead simple to set up and provides a number of features that are important to producers (zero latency, speaker emulations, target presets, etc.). The ease of use is off the charts compared to the RME. The musicians I know are much less inclined to want to fuss with this stuff than audiophiles.
ADI-2 DAC has a new software that is available with a firmware update that allows you to make all those adjustments from your computer which works well. Mac is already out and Windows is on the way I understand.
 

Zensō

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ADI-2 DAC has a new software that is available with a firmware update that allows you to make all those adjustments from your computer which works well. Mac is already out and Windows is on the way I understand.
That should be a big improvement. I guess that sort of proves my point that these types of detailed adjustments are best done in software on a large screen with a pointing device.
 

Music1969

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@JohnYang1997 do you measure your DACs with DSD inputs as part of QA/QC process?

I don't mean playing DSD music - I mean measurement test files.

I measured several Topping DACs and they are very bad with DSD256 test files compared with PCM input.

From what I see It appears from QA/QC Topping is not measuring with DSD256 and DSD512 inputs

I can send you test files if you want? What is your email
 

CleanSound

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Will Topping consider 430mm wide products? Many north Americans and Europeans prefer the full size to match the rest of gear in their AV rack.

You mentioned that Topping will make a version LA90 just as a power amp. Will Topping consider a much more powerful amp? And in 430mm?
 
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