HAA Resolute by Thrax Review

In this review we take a close look at the Headphone Auditions Amsterdam Resolute transportable amplifier by Thrax Audio, selling for €2,999 Euro.


Disclaimer: Headphone Auditions Amsterdam is not related to Headfonia in any way. The HAA Resolute by Thrax Audio was sent to me on loan to be featured on Headfonia.com.

Headphone Auditions Amsterdam

Headphone Auditions Amsterdam – aka HAA – is an incredible shop located in the center of Amsterdam, specialized in personal as well as desktop audio. If you want to listen to something before you buy it, this is THE place to go to. We actually visited the HAA store in Amsterdam a few months ago, you can find that article right here.

Headphone Auditions Amsterdam

Stefan – the owner of HAA – strongly focuses on the upper part of the market with units starting from a few hundred USD. The shop moto is “You can’t read sound, you have to listen”. Logically we don’t fully agree but it is true that you can always hear best for yourself. For a lot of products on the market that’s simply very hard to do, and so Stefan decided it was time to make that possible. I have to admit that he has built something very special in Amsterdam, and the amount of gear you can listen to simply is incredible. All you have to do, is make an appointment, show up on time, and then enjoy.

Now HAA is taking it a step further and they – together with Thrax Audio – have developed a transportable high-end amplifier named Resolute. And that’s what we’re looking at today.

Thrax Audio

Before we go into details on the HAA Resolute amplifier, we have to share some info on Thrax Audio first s they have never been featured on Headfonia before.

Thrax Audio is a high-end audio company located in Bulgaria and it is run by  Rumen Artarski, the founder and chief designer. They build all kind of high-end units going from speakers to turntables to DACs and amplifiers. On Thrax Audio’s website we can find the following:

Our team has members with life long experience in the fields of electronics and acoustics but also being ardent audiophiles all the time. Their knowledge and experience extends to areas not covered in any current academic curriculum. The other part of the team are recently graduated young professionals driven by the passion for audio and educated to the latest trends and cutting edge technologies.

The team has drive and creativity coming from young engineers with the error correction and wisdom of experience of the elders. A combination we see as unique in our field. This way no aspect is overlooked during product design as each team member has a different specialty that adds to the whole. Everyone sees the product from a different angle.

Resolute – Intro

Anyway, Stefan told me that he often gets people in his shop who have a high end portable setup, but no desktop setup. These customers were all looking for a small footprint solution to listen to 1 or 2 high-end headphones with, without having to invest heavily in a desktop source and amplifier. These customers want to use their high-end DAP and as such HAA then started thinking.

Together with Thrax they built the Resolute, a transportable, always-on high end amplifier. Designed to perform best with the SP3000, the Susvara and Abyss AB1266 headphones. In this article we will go into that deeper and connect it to a wider range of sources as well as headphones. You can find the Resolute’s dedicated web page here.

I first listened to the Resolute at the high-end Munich show back in May. It was hooked up to my SP3000 and I listened to the above mentioned headphones. I was impressed.

Resolute – Product

So, in short, the Resolute is a compact Power Headphone Amplifier designed to drive the most demanding Headphones, effortless. It is a high-end unit and it comes with a €3K Price tag. It can be ordered from HAA directly, and I think that’s the only source for now.

HAA explains: Resolute is the best term to describe this Amplifier that was born out of a problem. To solve this problem HAA wanted a solution that:

  • Doesn’t break the bank
  • Doesn’t create redundancies
  • Doesn’t require losing a lot of desktop real estate
  • Doesn’t lose any of the potential of the high-end headphone

It is very important to realize that the Resolute is a Power Headphone Amplifier. Just like a Power Speaker Amplifier it needs a Pre-Amplifier for volume control. Resolute will most typically sit in between your DAP and your Headphone, but any Pre-Amplifier will work. Just like any audio source with a built-in volume control, and you’re good to go. More on that later in this article.

Resolute – Usage

Resolute has no interface, no buttons, no batteries. It will switch on when the power cord and both the in and out are connected. The unit does get quite warm in use, so take that into account.

The Resolute uses 4.4 connectors and HAA offers cables separately coming from RCA, XLR and 4.4. HAA also offers a 3 meter power cable to allow for more flexibility with the placement of the amplifier. These cables are made by Nikolay Kozev from SIN Audio. Stefan sent me all of the connector cables to experiment with, and I do have to say that the SIN cables are really nice. Of course they will work with any cable brand. I myself have been using the Resolute with a huge AudioQuest NRG Z power cable.

Talking about using Resolute, it in fact is very easy. Just connect everything and use the volume control on your source to set your ideal listening volume. Make sure to not leave the volume maxed out from the last use. The only thing I do not like when using the Resolute is that it is quite light, and it doesn’t always stay firmly in place when in use. It doesn’t have any feet and the unit moves on your desk, scratching the casing. There’s a solution for that though! The actual production units will have feet on them, helping with the stability. Also, SIN Audio has built an extra light power cable specifically for the Resolute.

I myself put a soft cleaning cloth under it in order for it to keep its looks. Next to that, note that if you want to take the Resolute with you, you will also need to bring a full-sized power chord to the party. There’s no battery included, so this might complicate the transportability. I asked Stefan why there isn’t a power switch, and the answer was simple: “I wanted things to be as simple as possible”. Let’s hope we see a power switch in the future on a V2, or maybe as an option.

Design, Build quality and Specs

The design is simple and the Resolute comes with a nice aluminum case, available in grey or black. On the bottom of the units you can find the HAA logo and the safety certification info. There will be feet on the bottom of the production version. The Resolute works both on 110V and 220V.

The back of the unit features the power connector and on the front you on the left have the output, with the input right next to it. Personally, I would have switched these around but ok. It is a basic design with excellent build quality, even though I have the impression that the case easily scratches.

The HAA Resolute measures 19.5cm x 10cm x 3.5cm, and it weighs only 900g. You can look everywhere you want, but you will not find any specifications of the Resolute. HAA and Thrax of course do this on purpose, as not everything is about the specs. They prefer to let your ears do the judging. Maybe if you ask nicely, Stefan from HAA will share something, but I can’t guarantee that.

The Resolute unit does allow you to switch to a lower gain setting for easier to drive headphones such as the ELITE or even for IEMs. To do that you need to open the case, but that’s not difficult to do in case you do hear some noise with your easier to drive headphone. In this article we’re focusing on harder to drive headphones, as this really is what the unit originally is about.

I won’t be able to comment on the box, accessories, etc as we only received the unit (and cables) in a basic box and not the consumer product packaging.


The article continues on the second page, with all the parts on sound. Click here to go there directly.

Page 1: HAA, Thrax, Resolute

Page 2: Sound Pt 1

Page 3: Sound Pt 2, Conclusion, Summary

4.4/5 - (61 votes)

Lieven is living in Europe and he's the leader of the gang. He's running Headfonia as a side project next to his full time day job in Digital Marketing & Consultancy. He's a big fan of tube amps and custom inear monitors and has published hundreds of product reviews over the years.

Be first to comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.