WolfX700 Measurement of Topping A90 Headphone Amp

[JohnYang1997]

So can I use this as a preamp to a power amp?

Of course you can.

 

[bigLP]

Of course you can.

I hate to muddy this thread about the headphone amp, but it has already gone that way.....
@JohnYang mentioned earlier in this thread that they have a dedicated line preamplifier in the works(unless i misunderstood). Will that be more or less equivalent to the preamp side of this headphone amp? Hopefully with more inputs??? I am currently considering the gustard p26 and both of the schiit freya models. Hoping Topping soon has something to compete as well.

 

[JohnYang1997]

I hate to muddy this thread about the headphone amp, but it has already gone that way.....
@JohnYang mentioned earlier in this thread that they have a dedicated line preamplifier in the works(unless i misunderstood). Will that be more more less equivalent to the preamp side of this headphone amp? Hopefully with more inputs??? I am currently considering the gustard p26 and both of the schiit freya models. Hoping Topping soon has something to compete as well.

This A90 is a headphone amplifier with preamp capability. Electronically, it's more than a preamp would ever need. But the volume control is limited to a single Pot.
The dedicated preamp has relay controlled resistor arrays for better channel tracking and allows the remote control. If you like you can use the preamp as the dedicated volume control for A90. It's more of a convenience for A90 to be able to do the preamp work but it's designed with mainly headphone amplifier in mind.

 

[MPA1]

Hi John, That A90 is a lovely piece of kit! Good work!

The dedicated preamp has relay controlled resistor arrays for better channel tracking and allows the remote control.

Very nice to hear there is a dedicated preamp in the work, looking forward to that one. Would it be possible to include a tape out or HT bypass to that dedicated preamp?

 

[mslim]

Less power yes.

Yes. A good near field listening amp - fits in the product line up. Please consider having a subwoofer out.

 

[JohnYang1997]

Yes. A good near field listening amp - fits in the product line up. Please consider having a subwoofer out.

What do you consider as a woofer out? Just another line output or a low pass output?

 

[mslim]

What do you consider as a woofer out? Just another line output or a low pass output?

I’m not sure but I think at least LFE. Have to fit the targeted market. I think most subwoofer for this market have both. Not many have high level input.

 

[Hemi-Demon]

Release date? I sure wish that 2.5mm jack, was switched out for a 4.4mm.

 

[JohnYang1997]

Release date? I sure wish that 2.5mm jack, was switched out for a 4.4mm.

It is a 4.4mm jack.

 

[YSC]

one more noob question, in dacs we can see jitter which is a time domain error, so how about amps? will the feedback/forward topology makes jitter worse or so?

 

[YSC]

going back to old amps, just dug this review out at hometheatrehifi

https://hometheaterhifi.com/reviews...ic-taurus-mkii-balanced-headphone-amp-review/

seems that the old auralic was pretty good also? in numbers alone it seems better than the headamp GSX or so yet previous review of Tyll of innerfedility seems suggesting the opposite

 

[JohnYang1997]

going back to old amps, just dug this review out at hometheatrehifi

https://hometheaterhifi.com/reviews...ic-taurus-mkii-balanced-headphone-amp-review/

seems that the old auralic was pretty good also? in numbers alone it seems better than the headamp GSX or so yet previous review of Tyll of innerfedility seems suggesting the opposite

Subjective reviews for electronics most of the time = BS.

 

[Matias]

What do you consider as a woofer out? Just another line output or a low pass output?

Usually more line outputs, full range, since modern subwoofers are active and have low pass filter (even PEQ). Ideally 2 pairs of XLRs and 2 pairs of RCAs, but uses lots of space on the back...

 

[YSC]

Subjective reviews for electronics most of the time = BS.

Yea, but tyll mostly did review with his own measurements also so I am kind of having faith in his reviews, like how I purchased the Hifiman he500 in his measurement review showing how neutral tonality it have, and bought the Taurus for 6 years based on his review and measurements. Just kind of surprised the head amp gs x did poorer than the Taurus especially having better channel crosstalk.

btw dr yang, and result of crosstalk for the A90? I am really interested in how well it gets

 

[Hemi-Demon]

It is a 4.4mm jack.

Excellent and Thank You for correcting my poor vision.

 

[Billy Budapest]

Opamps Audiophile's worst nightmare.

No, true Audiophiles like them. It’s the Audiophools that don’t!

 

[imrul]

No, true Audiophiles like them. It’s the Audiophools that don’t!

So why don't they like opamps? What's the difference between the two? Why would an engineer decide to use one design over the other? What are the use cases and the pros and cons of each?

 

[Tks]

So why don't they like opamps? What's the difference between the two? Why would an engineer decide to use one design over the other? What are the use cases and the pros and cons of each?

An audio device manufacturer wouldn't be the one creating an OpAmp it seems, in the same way they wouldn't be creating the DAC chip itself in the same way.

It's like the same way why there are only just a handful of battery OEMs. You can't actually make your own battery that could ever compete on the market, simply because battery tech requires billions in R&D. Again.. likewise when Dell makes a computer, they aren't making any parts beyond housing. Or when you see a keyboard from Dell, or Corsair using mechanical switches. They're not actually making the keyboard themselves and the switch mechanism.

All of these devices in 99% of cases are built with companies that specialize in the creation in each of the parts. Again, you're never EVER going to make your own GPU that would resemble anything capable of competing with an AMD variant let alone an nVidia variant.

So what this is basically evidence of, is nearly all the advanced electronics we use, are either off-the-shelf parts that can be ordered (or if you're a preferred customer ordering parts in the millions of quantity, then you can actually have coffee with the OEM about designing a custom part of your own design perhaps, and they will work with perhaps realizing your ambitions).

This basically is beneath audiophiles (audiophools). Because using plebeian off-the-shelf parts is beneath them. It's mainstream garbage that barely executes on utility for those who simply have to have something barely functioning. They see any company doing work as much as possible in-house as virtuously more worthy of their attention and hard earned money, simply from the fact they're willing to do most of the design and (in theory) that allows the company the freedom to create products and parts that function better than the amalgamation of parts used in products from companies that use OPAMPS and DAC chips from AKM or ESS for example. It's why you see things like R2R still hold sway (R2R was a way of doing things before globlization made specilization of parts creation the logically efficient thing to do when trying to serve 7 billion people on the planet. Building R2R for every single DAC ever made in the presence of AKM and ESS is just idiocy, or just vanity seeking at this point in the same way a mechanical watch is, except mechanical watches don't try to lie and say they perform better than quartz, while audioidiotphiles think they can take the win on all fronts, aesthetics, performance, without something giving way).

The reason OpAmps are a nightmare for audiophools is because they're now good enough to beat custom designs that used to actually result in devices that would perform better than a DAC or AMP or whatever, built with off-the-shelf parts. Now those off the shelf DAC chips for example; plow right through all R2R implementations to a degree where R2R simply looks like vinyl, where there is NO chance by physics they can outperform things like dynamic range of digital.

So the nightmare, is the butthurt all their desires are for a technology that is getting slapped by approaches to design that are considered inferior in virtue of the less work required, that still produces measurably better performance on nearly all fronts.


And THAT is why - I hope as a layman - I think he said OpAmps are an audiophiles nightmare.

 

[maverickronin]

And THAT is why - I hope as a layman - I think he said OpAmps are an audiophiles nightmare.

Awesome. I started on a rant like this, but just wasn't feeling it today.

 

[Billy Budapest]

An audio device manufacturer wouldn't be the one creating an OpAmp it seems, in the same way they wouldn't be creating the DAC chip itself in the same way.

It's like the same way why there are only just a handful of battery OEMs. You can't actually make your own battery that could ever compete on the market, simply because battery tech requires billions in R&D. Again.. likewise when Dell makes a computer, they aren't making any parts beyond housing. Or when you see a keyboard from Dell, or Corsair using mechanical switches. They're not actually making the keyboard themselves and the switch mechanism.

All of these devices in 99% of cases are built with companies that specialize in the creation in each of the parts. Again, you're never EVER going to make your own GPU that would resemble anything capable of competing with an AMD variant let alone an nVidia variant.

So what this is basically evidence of, is nearly all the advanced electronics we use, are either off-the-shelf parts that can be ordered (or if you're a preferred customer ordering parts in the millions of quantity, then you can actually have coffee with the OEM about designing a custom part of your own design perhaps, and they will work with perhaps realizing your ambitions).

This basically is beneath audiophiles (audiophools). Because using plebeian off-the-shelf parts is beneath them. It's mainstream garbage that barely executes on utility for those who simply have to have something barely functioning. They see any company doing work as much as possible in-house as virtuously more worthy of their attention and hard earned money, simply from the fact they're willing to do most of the design and (in theory) that allows the company the freedom to create products and parts that function better than the amalgamation of parts used in products from companies that use OPAMPS and DAC chips from AKM or ESS for example. It's why you see things like R2R still hold sway (R2R was a way of doing things before globlization made specilization of parts creation the logically efficient thing to do when trying to serve 7 billion people on the planet. Building R2R for every single DAC ever made in the presence of AKM and ESS is just idiocy, or just vanity seeking at this point in the same way a mechanical watch is, except mechanical watches don't try to lie and say they perform better than quartz, while audioidiotphiles think they can take the win on all fronts, aesthetics, performance, without something giving way).

The reason OpAmps are a nightmare for audiophools is because they're now good enough to beat custom designs that used to actually result in devices that would perform better than a DAC or AMP or whatever, built with off-the-shelf parts. Now those off the shelf DAC chips for example; plow right through all R2R implementations to a degree where R2R simply looks like vinyl, where there is NO chance by physics they can outperform things like dynamic range of digital.

So the nightmare, is the butthurt all their desires are for a technology that is getting slapped by approaches to design that are considered inferior in virtue of the less work required, that still produces measurably better performance on nearly all fronts.


And THAT is why - I hope as a layman - I think he said OpAmps are an audiophiles nightmare.

I think the explanation is much simpler. In the 1980’s and 1990’s, audiophool rags like The Absolute Sound and Stereophile would rail against opamps because of an uninformed, unscientific belief that they must sound worse than discrete solid state or tube circuits because they were (supposedly) less expensive to implement.. Similarly, they nonsensically railed against the use of JFET and MOSFET transistors (using such make-believe terminology as hearing a “MOSFET mist” to the sound), preferring circuits using bipolar transistors. Finally, they insisted on solid state equipment using toroidal transformers and tube using E-I core transformers instead of other less impressive looking but in actuality better performing transformers such as split bobbin, R-core, or C-core (dependent on what the application warranted). Generally, they took the position that the older or more esoteric the technology, the better the sound. That’s why in large measure they preferred turntables to CD players and tubes to solid state. It was all quite silly and undoubtedly based on advertising dollars. They duped a lot of their readers into this type of thinking, and several of the biases they introduced, including their anti-opamp positions, survive to this day, 20-30 years later.