Amplifier? Preamp? Dac? what exactly is the Lyngdorf TDAi 2170?

I suppose the easiest classification would be an integrated amp, with an inbuilt DAC. But it doesn’t really have a DAC, even though it converts bits into an analog output. If you mention “DAC” to the folks at Lyngdorf they yell at you “NO, the TDAI-2170 is 100% digital, without sound-deteriorating digital-to-analog conversions!!”. But surely this is semantics, it really does have a DAC… “NO! the digital signal drives the speakers directly, with no translation and no middleman”. Ahh, gotcha. Whatever dude.

Let’s come at this from a different angle. Would anyone buy the Lyngdorf TDAi 2170 for use primarily as a DAC? Probably not. What about a basic integrated amp? Maybe, but probably not. Well, what then?


But not just room correction, you’ll want to use the DAC too. And the power amp. And probably use the optional USB input so you can plug your computer into it and stream. Oh, and the optional high-end analog module, so you can connect your turntable. What self-respecting audiophile doesn’t own a turntable?

Ok, this is just an opinion, but the only way the Lyngdorf TDAi 2170 makes real sense is if you use it for everything. Just go ahead and dump your preamp, your expensive power amp, your DAC, your DDC, and while you’re at it, dump your speaker crossovers, too.

Here’s the thing. When you use any one of the integrated components of the TDAi 2170 in isolation from the whole, it really doesn’t sound that great. I mean, it’s OK, but you wouldn’t want to buy this thing and just use its power amp section, or DAC, or whatever. You NEED to use the whole shebang, something about the whole being greater than the sum of its parts, to quote Aristotle.

Lyngdorf TDAi 217 review

Specifications (From Lyngdorf Audio Here)

Power rating: 2 x 170 W @ 4Ohm
Max output current: 30A
Audio specifications: 0.02% THD+N, 1W/4Ohm, Frequency response: ±0,5dB from 20 to 20,000 Hz
Digital inputs (Asynchronous): 2 x Coaxial Digital (≤192kHz / 24 bit), 4 x Optical Digital (≤ 96kHz / 24 bit)
Analog inputs: 2 x Analog Single-Ended RCA
Digital outputs: 1 x Coaxial Digital (96kHz / 24 bit)
Analog outputs: 1 x Single-Ended Analog
EQ: RoomPerfect™, ICC
Interfaces: 1 x RJ12 connector, 1 x trigger input, 1 x trigger output
Optional modules: HDMI module with 3 inputs (≤192kHz/24 bit) and one output / CEC and ARC compatible, Streaming USB input module (≤384kHz/32 bit + DXD / DSD64 / DSD128), High-end analog input module (1 Phono (MM), 3 analog Line inputs)
Remote control: Infrared
Dimensions (HxWxD): 10 x 45 x 36 cm, 3.9 x 17.7 x 14.2 in
Weight: 8 kg / 17.6
Finish: Anodized aluminum, matte black

Take note of ‘Optional Modules’ above. The stock unit comes without some things most of us will probably want. The unit under review here has all available extras excluding the Phono module. I have to draw the line somewhere. I can’t spend $30K on an ‘analog’ system, then chop up the signal in a four grand black box ($4999 with optional modules), although I’m going to do it anyway if I plug the phono output into the Lyngdorf’s analog input module, which quickly turns it into a digital signal.

The Story

This isn’t my first encounter with products from Lyngdorf. In fact, my experiences pre-date the foundation of Lyngdorf Audio, a breakaway company from what was once Tact Audio. Peter Lyngdorf started Tact Audio with a partner in 1996. The USA-based company produced the highly regarded TacT Millennium amplifier, which was recognized as the world’s first true digital amplifier. Trickle-down technology from the Millennium fed into the TACT RCS2.0, which was the unit I bought perhaps around 2010 or so. The TACT RCS2.0 had the Millennium’s Room Correction technology and was my first introduction to the technology. It worked well back then but ultimately lacked transparency.

Around the time of my owning the TACT unit, Peter Lyngdorf split from TACT Audio and took the technology with him to Denmark where Lyngdorf Audio became the descendant of the Steinway Lyngdorf partnership. (Peter Lyngdorf has had ownership involvement in a variety of companies including TACT Audio, Snell Acoustics, NAD Electronics and Dali A/S speakers). TACT Audio soon fell into disarray, seemingly unable to support their products effectively, and they soon discontinued their manufacturing business.

A while later, products started to emerge from Denmark under the Lyngdorf Audio brand. One of the early products was the TDAi 2200, which I owned for a good few years. The TDAi 2200 was very similar in function and operation to what was obviously its predecessor, the TACT Audio RCS2.0, but it was clear that it was a couple of generations ahead of the Tact in its ability to perform digital processing without significant coloration or loss of transparency. It was a great product and I liked it a lot.

The core technologies found in the current TDAi series (the 2170 reviewed here is actually discontinued, having been replaced at the time of writing by the TDAi 3400) are digital amplification and Room Perfect room correction software.

Digital Amplification

The TDAi 2170 is rated at 170 watts per channel, and uses a digital pulse code modulated (PCM) audio signal from a digital source (SPIDF, USB, HDMI, etc) and converts it to a pulse width modulated signal (PWM) which is then applied directly to the output stage, where it is converted to a low-voltage analog signal for driving the speakers. What are the supposed benefits of the Lyngdorf approach to digital amplification?

  • Ultra-Low noise in the signal path
  • Bit-perfect clarity and resolution
  • High dynamic range through the entire volume range – At low volume, your system will sound more dynamic.



Lyngdorf Audio not only states that their proprietary room correction system will eliminate the need for acoustic room treatments, they actually recommend that you remove any acoustic treatments from the room. For those of you with egg cartons taped to the walls around your room, this might be worth the price of entry alone.

Also, those of you married to the idea of pulling your speakers out into the room can now push your speakers, any speakers, hard up against the front wall.

But what about those of you who are somewhat technically challenged, is this going to be another nightmare, like trying to get your printer to print without borders? No, actually it isn’t. It’s all very simple. In fact, screwing together the mic stand was the most difficult part of the process.


A Quick Run Through The Basic Setup / Install

For most people, the TDAi 2170 will be a breeze to get up and running. Connect the amp outputs to your speakers, connect your analog source components, then connect the digital output from your CD player. Yes, it’s probably best to use your CD player as a transport, so simply obtain a 75ohm digital SPDIF cable and hook that into the appropriate input on the Lyngdorf. If you’re into computer audio and you have the optional USB input module, then go ahead and hook a good quality USB cable between your computer or a streamer and the TDAi 2170.

If you bought the TDAi 2170 on the used market, then I highly recommend that you start off by doing a factory reset. Once fired-up, use the remote to navigate to the settings screen and scroll through until you see the factory reset option. The reason for this is that you don’t know what weird and wonderful settings the previous owner might have programmed in. For example, they may have used the units crossover function and may have a high or low pass filter engaged on an output. Better to get rid of all that and start afresh.

Once everything is connected, powered, and reset, you’re basically ready to rumble. Select the correct source, up the volume control and you should be listening to music.

I found that the unit takes 24 hours to warm up fully. Not 24 hours to break-in, but 24 hours to warm up following the power being disconnected.


After you have music playing you’re ready to run the Room Perfect software. Simply plug in the mic cable to the rear of the unit and place the mic at your listening position pointing towards the speakers. (Follow the procedure in the manual, it’s a lot more insightful than I’m offering here!). Go back to the setup menu and select ‘Room Perfect Setup’ then follow the prompts. The TDAi will start the process by playing a test tone through your speakers. It will usually ask you to adjust the volume, which may be a little disconcerting as it will want you to adjust such that the test tone is pretty loud. It will then prompt you to move the mic position to a different part of the room, whereupon it will hit you with another test tone, and so on.

Each time a test tone is played, the software is recording and stores information about the frequency response of your room. As it records the response from multiple locations it will provide feedback through the display on what percentage accuracy has been achieved thus far. Typically, around 7 or so measurement locations will yield around 97/98% accuracy. When this level is reached, the software is relatively happy and it will prompt you to either conclude the measurement process or continue to capture that last couple of percent. I always run it as high as I can – in most rooms I’ve used the system in, 100% can be achieved.

Once measurements are complete, the system will prompt you to store the setup, and that’s basically it. Remove the mic, sit down, and have a listen.

You can quickly hear the difference room correction makes by disabling correction via the remote.

You can go on to use the TDAi in a far more sophisticated setup, for example, replacing the passive crossovers on your speakers and using the active XOs in the unit. Most people won’t do this, but there’s another feature that many will use –

Subwoofer Integration

You can connect the analog outputs to your subwoofer plate amp(s) and use Room Perfect to configure a 2+1 or 2+2 system with subs. You’ll want to read the instructions, it isn’t difficult, but the are setup parameters that can easily be misconfigured if you’re not careful. The process is basically the same as before, though this time you’ll want to integrate the subs manually to get the best bass response before initiating the room correction setup. Lyngdorf recommends that you place the subs in the corners behind the main speakers to give you optimal boundary reinforcement. In my experience, it isn’t entirely necessary to position them this way, find the best place in the room for subs as you would with any conventional 2+2 setup, and start there.

Passive Sub Integration – if your subs are of the passive variety, and you have a spare two-channel power amp, you can still use the Lyngdorf TDAi 2170, in fact, you have a couple of options. If your spare 2-ch amp is of modest quality, and sufficient power, then use it to drive the subs. Simply connect the main speaker pair to the speaker outputs of the Lyngdorf, then use the analog (pre) outputs to run to the 2-channel power amp. Then connect the 2-ch amp to your subs. You’ll then need to configure the outputs inside the Lyngdorf via the menus. You’ll want to set a low pass filter on the analog outputs so you’re not sending a full range signal to the power amp driving the passive subs. You can set a high-pass filter on the main speaker outputs if you want, I prefer to run the mains full range.

Another interesting option for running passive subs is to introduce a high-quality power amp, then use the amp inside the Lyngdorf to drive the subs, then use the Lyngdorf’s analog outputs to drive your own power amp. This is a great feature for tube amp owners who want to use the TDAi as a preamp/DAC, but not to have to sacrifice tubes in their system. To do this setup is very simple, you’ll basically be flipping the high and low pass filters so that low pass is on the main speaker outputs and high pass is on the analog outs (or full range on the analog outs).

If you’re interested in the crossover features of the TDAi 2170, and how it can be used in a fully active loudspeaker system, then you might be interested in the project I wrote about involving vintage Altec Lansing Valencia speakers.

Below is a basic layout of the system with a First Watt J2 power amp fed from the analog outputs on the TDAi 2170 and the crossovers removed from the speakers.

Lyngdorf TDAi 2170 crossovers

How’s It Sound?

As I’ve already stated, you’ll get the best results by using all of the integrated features of the TDAi 2170. Sure, you can use your own DAC, or use the analog output from your CD player, but in most instances, things will sound better if you use what’s available within the Lyngdorf. I’ve proven this theory using a range of different equipment options and configurations, too plentiful to try and write about here. The only exception I would make to this general rule is if you have a quality tube amp and you want to continue to use that to drive your main speakers. But be sure to at least try the amp on the TDAi at some point, you might just be amazed at how good it is and how non-digital it sounds.

And the unit really does sound great. It’s amazing how close it came in my room to a separates system costing over $40K. The TDAi renders a deep and wide soundstage and images are tight and focused. Bass is extended and taught, perhaps a little dry sounding, but ultimately very satisfying. The top end has plenty of extension, air and sparkle, but never sounds harsh unless harshness is an artifact of the actual recording. This unit does not sound digital, and Lyngdorf themselves would be quick to remind us that it isn’t. So what are its weaknesses, how does a $40k pre/power combo improve on the modest TDAi 2170? (Veloce Audio LS-1 and Saetta monoblocks). Most notably the more expensive rig provides a little more body and flesh to instruments and vocals. There’s a little more substance and presence to elements in the soundstage that helps a little in moving one closer to the sense of a live performance taking place in the room. But we’re talking small margins, and you’ll pay a lot of money to gain this marginal advantage.

ORIS 150 horn system

One of the most valid anecdotes I can think to provide relates back to my time with the TDAi 2170’s predecessor, the TDAi 2200. At the time I owned a pair of large horn speakers that were incredibly efficient and quite revealing. I spent a lot of time and money on flea-powered tube amps trying to get those speakers to open up and sing, but it wasn’t until I used the 200 watt/ch TDAi 2200 that I really got to hear what those horns were capable of. Despite their 106 dB efficiency, the Lyngdorf was dead silent, remarkably transparent, and free from any harshness or grain. The same is true of the more modern 2170.

A while back I reviewed the Devialet Expert Pro 220 CI, a machine of equal versatility and boasting state-of-the-art technology. Similar in respects to the architecture of the Lyngdorf, with power/pre/dac functionality, the Devialet differed primarily with its absence of room correction, replaced by Devialet’s proprietary SAM system of matching the hardware/software to a known database of speaker models. I found the Devialet to be harsh and quite clinical and very ‘phasey’ sounding. It was obviously digital gone bad, whereas the TDAi 2170 doesn’t sound digital at all.


Wrapping Up

As you can see from the above, the Lyngdorf TDAi 2170 is an extremely versatile piece of kit. You can run it as a dac/pre/power or at the heart of a 2+2 speaker management system. It also has options for integrating visual, via optional HDMI modules, which work great too.

The main thing here is that the TDAi 2170 sounds fantastic, particularly if your room suffers from poor acoustics. Once you get everything hooked up and the Room Perfect software operational, the setup will compete sonically with systems costing much, much more. Imagine having a system of expensive separates and selling off your power amp(s), preamp, DAC, cables, accessories, etc, and replacing it with a single box that retails for around $5K fully equipped. And not sacrificing any sound quality whatsoever! This little box from Lyngdorf can sit at the very heart of any high-end audiophile system.

CAH – 12/2022