• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are daily reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

TP RA3 Rackmount Amplifier Review

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 7 2.5%
  • 2. Not terrible (postman panther)

    Votes: 12 4.3%
  • 3. Fine (happy panther)

    Votes: 94 33.8%
  • 4. Great (golfing panther)

    Votes: 165 59.4%

  • Total voters
    278

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
44,209
Likes
232,237
Location
Seattle Area
This is a review and detailed measurements of the TP (Topping) RA3 stereo balanced rackmount amplifier. It was sent to me by the company and costs US $229.
TP Topping RA3 Rackmount stereo amplifier balanced Review.jpg

Yes, this is a new sub-brand from Topping. I quite like it. The large and highly visible volume level is as gorgeous to look at as it is responsive. A remote control is provided which is something you don't usually get. The remote (or front panel) allow you to select between RCA and XLR input:
TP Topping RA3 Rackmount stereo amplifier balanced back panel Review.jpg

For those of us who have a DAC and an analog source, this is all that we need.

Lots of nice touches are there such as independent memory for the volume setting for RCA vs XLR. Safe volume settings. Trigger support and ability to update firmware in the future. Love that despite low cost, the power supply is built in. You have a hard power switch which puts the unit in standby. Push the volume knob or the remote button and it powers on.

This line of products, at least for now, will be sold by Topping direct. Alas, it is not yet on the website so you may have to wait a bit to order it.

I don't know anything about the design but based on measurements below, it seems to be a highly optimized class D chip architecture.

TP RA3 Amplifier Measurements
Let's start with our usual dashboard of 1 kHz tone into 4 ohm load at 5 watts:
TP Topping RA3 Rackmount stereo amplifier balanced measurements.png

Distortion is kept below threshold of audibility at around -116 dB. So noise is the only thing we need to worry about. There, when combined with distortion, nicely lands RA3 in our top 20 best amplifiers ever tested:
best rackmount amplifier review.png


Top rackmount amplifier review.png


Mind you, noise performance is excellent:
TP Topping RA3 Rackmount stereo amplifier balanced SNR measurements.png

Survey of available music indicates best case dynamic range of 18 bits and TP RA3 gives you that at just 5 watts! Allow it to go to its max power and it reaches 20 bits.

Multitone showcases the very low distortion in mid frequencies where our hearing is most sensitive:
TP Topping RA3 Rackmount stereo amplifier balanced Multitone measurements.png


But if you insist on pumping ear deafening high frequency tones into it in the form of 19 and 20 kHz tones, you naturally get more distortion:
TP Topping RA3 Rackmount stereo amplifier balanced 19 20 kHz measurements.png


A concern with low cost class D amp ICs is load (speaker) dependency. Topping has worked hard to make that basically a non-issue:
TP Topping RA3 Rackmount stereo amplifier balanced Frequency Response measurements.png


Crosstalk is incredibly good, besting even our reference:

TP Topping RA3 Rackmount stereo amplifier balanced Crosstalk measurements.png


Let's measure power into 4 ohm:

TP Topping RA3 Rackmount stereo amplifier balanced power 4 measurements.png

TP Topping RA3 Rackmount stereo amplifier balanced max and peak power 4 measurements.png


As noted, measurements completely match Topping spec of 130 watts at 1% THD+N. Not boundless power but very good for many. Naturally we lose good bit of power if you have a rare 8 ohm speaker:
TP Topping RA3 Rackmount stereo amplifier balanced power 8 measurements.png


Varying the frequency we do see the class D chip amp create more distortion above 5 kHz or so:
TP Topping RA3 Rackmount stereo amplifier balanced power 4 vs frequency measurements.png


There is a bit of a noise spike with power off:
TP Topping RA3 Rackmount stereo amplifier balanced power on off noise measurements.png


There is some inconsequential spikes in one channel in the first short minutes as the amplifier warms up:
TP Topping RA3 Rackmount stereo amplifier warm up measurements.png


Speaking of that, the amplifier didn't feel to be rising above room temperature in my testing -- on top anyway.

Finally, here is the efficiency vs output power (per channel -- both channels driven):
TP Topping RA3 Rackmount stereo amplifier balanced Efficiency measurements.png


Idle power while on is about 9 watts.

The protection circuit is aggressive in the way it shuts the unit down when pushed hard so I did not try to run my reactive load tests.

Conclusions
It is remarkable to me how Topping is not only capable of producing new product one after the other, they do so while striving for state of the art in performance. This is so even though they are bound by the capabilities of the class D chip amplifier they are using. I really like the larger form factor as it not only allows better dissipation of heat and inclusion of AC power supply, but also makes the unit more substantial and "professional looking." If they made the rack ears optional, they would fit nicely in a home system as well.

Feature set is great for this class of product with inclusion of remote control, trigger support, nice and visible volume level, etc.

It is my pleasure to add TP RA3 to my recommended list. Incredible performance for so little money.

-----------
As always, questions, comments, recommendations, etc. are welcome.

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
 

respice finem

Major Contributor
Joined
Feb 1, 2021
Messages
1,867
Likes
3,768
Price / performance ratio is hard to beat IMHO. The choice of LS terminals is interesting, "pro amps" usually have either SpeakOn or those compact screw-in terminals, don't they? It seems Topping also had home users in mind, which may be a wise decision - there are only so many pros, but many more home users.
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
44,209
Likes
232,237
Location
Seattle Area
Incredible performance for the price! Would it be possible to take a look inside? Thank you for your hard work (as always)....
I will think about it. :) Now, I need to go to sleep.....
 

Sokel

Master Contributor
Joined
Sep 8, 2021
Messages
5,579
Likes
5,500
Power cube???

Thanks Amir!
 

Talisman

Addicted to Fun and Learning
Forum Donor
Joined
Mar 27, 2022
Messages
815
Likes
2,274
Location
Milano Italy
applause for the excellent performance, I'm a little confused by the fact that in this type of product you are generally looking for great power even at the expense of performance. Here it is the opposite, for performance and power it looks like a replacement for the pa5, but the form factor clearly cannot attract the same customers.
Curious to understand what was the business logic of this choice.
Be that as it may, at that price I will certainly buy one too, but only if it is on sale on amazon, with all the associated protections
 

TonyJZX

Major Contributor
Joined
Aug 20, 2021
Messages
1,847
Likes
1,762
a surprise but a welcome one

i think power is less than i would guess given the rated specs but 57w isnt too bad???

maybe wait for reliability reports first but i mean everything else is pretty spot on... i like the 1ru 19" form factor BUT i feel like for the power given i reckon you're getting shipped a lot of Shenzen air.

But you get the removable feet and the remote and what looks like a unity gain vol, display... and realistically $229 is lower than I would expect given that everything is bigger. Is there a XLR amp like this under $300 w/ 19" format?

The matching RD3 dac is probably less interesting.

I also think that this whole line is kind of begs the question... why 19" rack?

and is there going to be more stuff in this format? like i dunno? a headphone amp? dunno what else people want in 19" format?
 

Tovarich007

Active Member
Joined
Jan 31, 2021
Messages
163
Likes
214
OK, very good performances but more powerful class D amps with very good performances can be found at about the same price level. I'm not that impressed.
And why create a sub brand ? I understand less and less the marketing and releasing politics of Topping ? Too many prducts with approximately same level of price and performances.

And how can the peak power be (slightly) lower than the maximum output ? Or is it an interversion in left and right graphs ?

And may we get more details about the implementation, the reference of amp module and power unit ? Is the quality construction and reliability as good as the measured performance (for a model supposed to be used in a pro or HC rack, it's important).

And if you want to build a DIY active amplification, it's simpler and better IMO to use Hypex (or Powersoft or RAM) solutions, for example like this : https://www.hypex.nl/products/amplifier-families/ncore-active-speaker-family/ more integration, less used space, more power, top perfromances, it's worth the extra price.
 

Dennis_FL

Addicted to Fun and Learning
Forum Donor
Joined
Feb 21, 2020
Messages
522
Likes
411
Naturally we lose good bit of power if you have a rare 8 ohm speaker:

I didn't know 8 ohm speakers were rare. I did a quick search of my KEF LS 50 metas and sure enough, they are 8 ohms. I need an education in impedance !!!!
 

TonyJZX

Major Contributor
Joined
Aug 20, 2021
Messages
1,847
Likes
1,762
yeah the TP branding I dont like... over here we take that as "Toilet Paper"

also who does the amp chip? is it TPA, infineon?

to the above person i would not compare it to Hypex... you're not even getting all these features in a Hypex for even triple the cost

I also get that with the release of the Fosi V3 one wonders why you would spend more given it benches similar but does like 85w!

BUT what you're paying for is the integration... no one yet is doing this all in a 19" package.
 

Chester

Senior Member
Joined
May 22, 2021
Messages
418
Likes
993
Nice little product. Surely this Topping Pro thing is just a branding exercise and they’re not really trying to market to pros?

At that price point, decent longevity from components and build quality (that can tolerate regular abuse) must be quite low I would have thought.
 
Top Bottom