Topping A70 Pro HP & Preamp Review

[Funnyjelo]

As usual with everything with Topping (A90D is a great recent example):

Wait 6 months for Topping design/production/QA/QC issues to be resolved and firmware updates to be released.

Apart from that - stellar performance. I can't believe the practically zero distortion plots. Amazing.

I'll buy one in November lol

Did you have issues with the A90d? I ended up having two short out on me. Topping service has been great but I ended up with a refund and not a device.
I have an a30 pro and want a volume preamp but I wasn't sure if I should wait on this one too.
I have loved my topping products and the A90d is the only one with any issues for me.

 

[marcom22]

But I dont know if its better the A90D or A70pro from PREamp audio perspective. Mmmmhhhh for me the A90D is still better as preamp, what do you think? Thanks

 

[Ken Tajalli]

I really do think this is the front end for my system I am looking for. Remote controlled relay step attenuation with perfect output. Massively powerful headphone. All the I/O I need (1 digital and 1 analog source). And a gorgeous display. There are very, very few products with a similar package in this price range. I think my Lyr+ may be on the chopping block.

What digital input?
Consider it as a straight wire with volume control , plus a headphone amp on the side.
Preamp is a misnomer. In my book, a preamp would at min. have input switching facilities, if nothing else.

 

[staticV3]

These look like they'd be really good for the Hifiman HE-6 series and Susvara. At 60ohm and 83dB@1mW, hitting the 120dB mark takes about 5W.

At 60Ω, the A70 Pro can play a whole 4% louder than the L70 (+0.5dB), for 40% more money.

 

[MAK1975]

That makes sense if you are using the Jot headphone amp as the test. Both DAC's would be bottlenecked by the Amp itself which doesn't produce much over 90 SINAD at a normal listening volume.
I personally also have an SU-8S and I can confirm the quality is SOTA. To me it clearly sounds cleaner vs some other lower tier products I have tested through my testing program.

What tracks are you playing? What music do you listen to?

Songs to test Audio Quality

Songs to test Audio Quality · Playlist · 31 songs · 38 likes

open.spotify.com

^This playlist has several tracks from different genre's that I have selected which have specific frequencies that highlight differences in performance or make it easier for you to hear the differences in performance.

Test tracks I was using were as follows: Gogo Penquin's new album Everything is Going to Be OK - Tracks - You're Stronger than you Think & Saturnine, Fleetwood Mac Rumors Album - track - Dreams, Lana Del Rey - Album: Norman Fucking Rockwell - Tracks - Doin' Time and Bartender, Michael Kiwanuka - Album - Love & Hate Album - Track Love & Hate, Massive Attack - Album Mezzanine - Track- Angel, Chet Baker - The Italian Sessions - Track - Well, You Needn't, The Danish String Quartet - Album Last Leaf - Track AE Romeser.

I listen to a whole variety of genres from alternative pop/rock, Electronic, Alternative Dance, Classic Jazz, and Classical music.

All these tracks seem to be well recorded. Some have more of a dynamic range than others. It's an interesting observation on the Jot1 bottlenecking the 2 DACs due to its low SINAD. Only way to see if there is any difference would be able to do some AB blind tests between the Jot1 and another Headphone Amp. See if I am able to pick out any dynamics/clarity between the 2.

Could also just being my hearing at age 48.

 

[Talisman]

Could also just being my hearing at age 48.

This is the only important thing.
If you can't hear the difference, you don't need to worry about it. Stop. End of the story.
Your money has to go where it makes a difference, it makes no sense to buy a dac that measures much better, if you can't hear the difference blind with your old dac, this is a reality that sadly many asr members find it hard to accept blinded by "superb measurements" no less than audiophiles buying a new cable to smooth out the sound.
Both are spending money on something that MAKES NO DIFFERENCE to their ears.

 

[restorer-john]

Is the entire screen touch enabled?

 

[staticV3]

Is the entire screen touch enabled?

From what I understand, it's only the three buttons on the side that are touch-enabled:


Kind of like Android's old Home, Back, Task Manager buttons, just rotated 90°:

 

[bequietjk]

One amp to rule them all

For now...

 

[Music1969]

Did you have issues with the A90d? I ended up having two short out on me. Topping service has been great but I ended up with a refund and not a device.
I have an a30 pro and want a volume preamp but I wasn't sure if I should wait on this one too.
I have loved my topping products and the A90d is the only one with any issues for me.

The early A90D i had , had the known issues. Returned it

The one I had 6 months later had no issues but I preferred 47k ohm input impedance of my SMSL SP400

 

[Ken Tajalli]

@amirm
three minor questions:
- was the test done with ground lifted?


- does it do RCA in, Balanced out? and vice versa? (edit: yes it does)
- If the answer to above is yes, then it must have two buffered outputs, I suppose one of the outputs can go to a sub. am I right? (edit: yep can do)

 

[raif71]

I don't get the relevance of 20K input impedance to say 5K. or even 100K.
perhaps someone can explain it to me. Thanx.

The 20k input impedance for an amp is so that the amp can match with more DACs that have a certain output impedance. The rule of thumb is that the amp should have at least 8x or 10x the impedance value of the DAC. For example, Denafrips Ares II has around 2k output impedance and L70 has 2k input impedance. This pairing obviously do not match as this is only 1:1 ratio and I guess one would get weird sounds from the pairing. If one were to upgrade the amp to A70pro, then the 20k impedance would have 1:10 ratio to the denafrips, so that would be perfect. Basically, the higher the impedance for an amp is so that it can better match with any DAC that connects to it.

edit : The Ares II's output impedances were even higher, at 2.4k ohms, balanced, and 1.2k ohms, unbalanced. So the example above if one were to use balanced connection between amp and dac

 

[Jochen]

It's not distortion free, just below the noise floor of Amir's AP (see plots below).

Ok, but from a practical standpoint, this may be considered distortion-free (analogously to dithering)

There are already headphones around that need that power to reach impressively loud levels.

Like which ? Without looking at the specs I could only think of the Susvara, Hifiman HE-6 or Stealth.

 

[Ken Tajalli]

The 20k input impedance for an amp is so that the amp can match with more DACs that have a certain output impedance. The rule of thumb is that the amp should have at least 8x or 10x the impedance value of the DAC. For example, Denafrips Ares II has around 2k output impedance and L70 has 2k input impedance. This pairing obviously do not match as this is only 1:1 ratio and I guess one would get weird sounds from the pairing. If one were to upgrade the amp to A70pro, then the 20k impedance would have 1:10 ratio to the denafrips, so that would be perfect. Basically, the higher the impedance for an amp is so that it can better match with any DAC that connects to it.

Thanx for the reply.
Are you sure? I just checked Denafrips, it says 625 ohms. Most DACs have output impedances less than that. Any more and it is an oddity (cheapest Schiit DAC is at 100R). I must admit, any amp input impedance less than 5K is an oddity, too. I can only imagine such a low impedance input can only serve in an absolute lowest noise measurement competition. A competition between Topping and itself!
I would say, past 5K input impedance, it becomes irrelevant for most practical scenarios.

Denafrips Ares II | willowtreeaudio

The Ares DAC is a 20Bit/1536KHz, native DSD1024, discrete resistor ladder Digital To Analog Converter, also known as R-2R DAC.

www.willowtreeaudio.co.uk

 

[raif71]

Thanx for the reply.
Are you sure? I just checked Denafrips, it says 625 ohms. Most DACs have output impedances less than that. Any more and it is an oddity (cheapest Schiit DAC is at 100R). I must admit, any amp input impedance less than 5K is an oddity, too. I can only imagine such a low impedance input can only serve in an absolute lowest noise measurement competition. A competition between Topping and itself!
I would say, past 5K input impedance, it becomes irrelevant for most practical scenarios.

Denafrips Ares II | willowtreeaudio

The Ares DAC is a 20Bit/1536KHz, native DSD1024, discrete resistor ladder Digital To Analog Converter, also known as R-2R DAC.

www.willowtreeaudio.co.uk

View attachment 285213

Thanks for the check...I got the number from google

Gramophone Dreams #40: Denafrips Terminator & Ares II Measurements

Measurements, from November 2020 (Vol.43 No.11)

www.stereophile.com

 

[Ken Tajalli]

Thanks for the check...I got the number from google

Gramophone Dreams #40: Denafrips Terminator & Ares II Measurements

Measurements, from November 2020 (Vol.43 No.11)

www.stereophile.com

Check manufacturer's.
Stereophile got Terminator's right.
According to the manufacturer, they all have the same output impedances, which is mighty high, even at 600R. Most DACs are in tens of ohms, a few of them at few hundred. At any rate, where did we get 20K input impedance from?
Did Amir mention it? It is not on Topping website!
This is a non issue.

 

[staticV3]

At any rate, where did we get 20K input impedance from?
Did Amir mention it? It is not on Topping website!

Sure is:

https://www.tpdz.net/productinfo/1009982.html

 

[Ken Tajalli]

Sure is:
View attachment 285215
https://www.tpdz.net/productinfo/1009982.html

missed that, thanx.
Topping site is way TLDR!
I checked the specs, it wasn't there.
Anyhow, I think it is a non issue.

 

[Music1969]

Anyhow, I think it is a non issue.

There's many pro audio interfaces with output impedance in the hundreds of ohms.

20k ohm input impedance helps pair with those.

My SMSL SP400 (THX AAA 888 like Benchmark HPA4 has) has 47k ohm input impedance, near 0 output impedance - more flexible with more DACs

Also has relay based vol control.

 

[maxxevv]

Extremely nice Amp here. As I mentioned in the D70 Review I think that the new design is a little less "clean" with a complex display and such. However the new features are welcome.
Performance is amazing and overkill... honestly I am not sure what headphone needs this much power? I

Maybe the Raal SR1a.