• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). Come here to have fun, be ready to be teased and not take online life too seriously. We now measure and review equipment for free! Click here for details.

Review and Measurements of Lyngdorf TDAI-3400 Amp & EQ (Part 1)

PuX

Member
Joined
Feb 16, 2018
Messages
82
Likes
37
#41
We are talking about an industry (press) that doesn't measure much these days. So marketing department is not pushing the designers to perform in this regard. Hopefully through the work we are doing, this will be resolved in the next few years.
yep, seems like most of the budget goes into marketing.
it would be great to see the tech speak for itself.

now all the companies have to do is to publish a few articles full of buzzwords and people will buy whatever.
 

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
19,492
Likes
20,590
Location
Seattle Area
#42
0.1% THD and 1% THD is an oft quoted spec on product manuals.
Not that I have seen. There is no standard or even convention for using such THD rates. Power is everything in marketing of amplifiers and rates distortion ranges from no mention to anything they want to use. To wit, the Lyngdorf in review here has no indication:

1550173327348.png


Here is Schiit:

1550173360096.png


So no, there is no such standard and hence justification for me to do it.

We are much better off encouraging the industry to publish power spec at the design limit as I am doing than using high THD numbers.

What do we do if an amp has no hockey stick by the way? That is, it is distortion-less to the limit. You want to put that in a table at the same power level but 1% THD for others? My scheme allows for that for publishing power before large amount of distortion sets in.
 

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
19,492
Likes
20,590
Location
Seattle Area
#44
Will part 2 come before or after REW measurement tutorial part 2? :p
Before. :) Although I am still have to shovel snow on daily basis so review work has slowed down. Just spent 3 hours with this toy electric blower. :(
 

Krunok

Major Contributor
Joined
Mar 25, 2018
Messages
3,177
Likes
1,533
Location
Zg, Cro
#45
Before. :) Although I am still have to shovel snow on daily basis so review work has slowed down. Just spent 3 hours with this toy electric blower. :(
This year we have unusally mild winter but, as I know the drill, I'm sincerely sympathising with you. :D
 

Jimster480

Major Contributor
Patreon Donor
Joined
Jan 26, 2018
Messages
1,039
Likes
548
Location
Miami
#46
Wow... Yet another "high end top quality" brand dethroned!

It really does seem like companies are designing by marketing rather than engineering these days.
 

Krunok

Major Contributor
Joined
Mar 25, 2018
Messages
3,177
Likes
1,533
Location
Zg, Cro
#47
Wow... Yet another "high end top quality" brand dethroned!

It really does seem like companies are designing by marketing rather than engineering these days.
These days..? I don't think so. It was always like that. Independent measurements were even less common before than they are these days so they could write whatever they seem fit on the spec sheet. Taking into account that huge number of folks don't take measurement seriously even today but put more trust into their "golden ears" instead I don't see things changing any time soon. Said, but true..
 

Willem

Active Member
Joined
Jan 8, 2019
Messages
291
Likes
218
#48
This review makes me all the more curious about the new DSPeaker Antimode X4. Apart from the fact that it has no power amplifier, it is quite similar to the Lyngdorf: DAC, pre amp, dsp room eq (and also automatic main/sub crossover). And it too is expensive.
 

Willem

Active Member
Joined
Jan 8, 2019
Messages
291
Likes
218
#50
To be sure, I meant the DSpeaker X4 and not their earlier Dual Core or the subwoofer only AM 8033.
 
Joined
Feb 14, 2019
Messages
16
Likes
1
#51
I read about this review on another forum, that's why I signed up and that's why this is my first post here. I own a TDAI-3400 so everything that is written about it has my special interest.. ;)

@amirm my first reaction after reading your review was, could it be that you had a faulty unit on hand? Especially because some (unexpected) outcomes only concerned one channel. Did you confront/consult Lyngdorf about your findings?

Secondly, I think it is a strange decision to review this unit as a 'traditional' DAC. Almost no-one will use a TDAI-3400 as a DAC to drive an (analogue input) amplifier. I think that - given the concept - it is not strange that the output stage / D-to-A is not of the highest quality. In 9 of the 10 instances these outputs will only be used to drive subwoofers via its cross-over function. The TDAI-3400 is essentially a powerDAC and excels in driving speakers via its speaker outputs. I actually compared the TDAI-3400 to NCore, Ayre, Devialet amongst others and preferred it. By ear but nonetheless.

That said, I use (and love it) as an amplifier, very good DRC and as a cross-over but I drive it counterintuitive with a Chord DAVE via its very high quality analogue inputs (optional module). This easily bests feeding the TDAI a digital signal. Best digital inputs by the way are AES/EBU and S/PDIF. USB and ethernet are not best-in-class so not strange that your test via USB did not measure well.

Lastly, I wonder if it could be that the Lyngdorf ICC (Inter-sample Clipping Correction) function did blur your outcomes and measurements. In my (very resolving) setup ICC 'enabled' degrades the SQ. I notice a relay switching when toggling this function so I suspect that ICC puts extra electronics in the pathway. Also the subsonic filter that Lyngdorf implemented could be a factor. Both ICC and the subsonic filter are enabled after a factory reset, as you did.
 
Last edited:

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
19,492
Likes
20,590
Location
Seattle Area
#52
I read about this review on another forum, that's why I signed up and that's why this is my first post here. I own a TDAI-3400 so everything that is written about it has my special interest.. ;)
Welcome to the forum. :)

@amirm my first reaction after reading your review was, could it be that you had a faulty unit on hand? Especially because some (unexpected) outcomes only concerned one channel. Did you confront/consult Lyngdorf about your findings?
The owner asked me the same question. My experience with anything broken is that the effect is global and quite extreme. The issues I see of noise, ultrasonic content, etc. does not get caused by broken unit. It could however be sample to sample variation. This said, I plan to perform listening tests and if the issues don't manifest themselves, I will be sure nothing is broken.

As to contacting Lyngdorf, it is my policy to not go and chase manufacturers. I expect them to monitor the web for reviews of their products and if interested, contact me.

Secondly, I think it is a strange decision to review this unit as a 'traditional' DAC. Almost no-one will use a TDAI-3400 as a DAC to drive an (analogue input) amplifier. I think that - given the concept - it is not strange that the output stage / D-to-A is not of the highest quality. In 9 of the 10 instances these outputs will only be used to drive subwoofers via its cross-over function. The TDAI-3400 is essentially a powerDAC and excels in driving speakers via its speaker outputs. I actually compared the TDAI-3400 to NCore, Ayre, Devialet amongst others and preferred it. By ear but nonetheless.
My testing reflects the interest of the forum. Here, people like to know if the DAC subsystem of any audio product is up to par independent of any other functionality. It is a good litmus test of engineering excellence. Also, people like to eliminate their music-centric DAC if they can with these integrated systems.

That said, I use (and love it) as an amplifier, very good DRC and as a cross-over but I drive it counterintuitive with a Chord DAVE via its very high quality analogue inputs (optional module). This easily bests feeding the TDAI a digital signal. Best digital inputs by the way are AES/EBU and S/PDIF. USB and ethernet are not best-in-class so not strange that your test via USB did not measure well.
I tested S/PDIF and its performance was the same as USB from what I recall. The DAC implementation is the limit of performance here, not the input.

Lastly, I wonder if it could be that the Lyngdorf ICC (Inter-sample Clipping Correction) function did blur your outcomes and measurements. In my (very resolving) setup ICC 'enabled' degrades the SQ. I notice a relay switching when toggling this function so I suspect that ICC puts extra electronics in the pathway. Also the subsonic filter that Lyngdorf implemented could be a factor. Both ICC and the subsonic filter are enabled after a factory reset, as you did.
Oh, I did not realize it had enabled them. I will check. For my testing though, I lowered the levels more than what I measured and it made no difference. So I don't think there is an issue with clipping.
 

MZKM

Senior Member
Joined
Dec 1, 2018
Messages
303
Likes
196
Location
Land O’ Lakes, Florida
#53
What do we do if an amp has no hockey stick by the way? That is, it is distortion-less to the limit. You want to put that in a table at the same power level but 1% THD for others? My scheme allows for that for publishing power before large amount of distortion sets in.
Do you mean it simply does not output any more wattage, it just stops at say 0.01%? If so, that’s valid but also not that common. Most extreme is usually similar to the Benchmark AHB2 where it shoots almost straight up:

And yes, that’s 0.0001% THD (-120dBFS) at 5W into 8ohm!

To help illustrate why I don’t like the hockey stick method, let’s look at the PS Audio BHK 300’s wattage into 8ohm as measured by Stereophile:

You might call that ~180W as that’s where the “knee” is, but at 0.1% THD it’s ~325W, almost double.

When music is playing, 1% THD (-40dBFS) is the often quoted threshold of audibility in the upper treble (depending on playback volume, even 100% THD at 20Hz may not be audible), Axiom Audio for instance did a small human trial and found it to be pretty true.

However, since THD stacks, I don’t like using 1% THD specs, as if you have a DAC, pre-amp, a MiniDSP, and a power amp, you then would exceed 1% THD (20*log10(4*10^(-40/20))), for the total to be 1% for 4 components, the average for each would need to be ~0.25%.

But as you’ve said, you post the graphs, so we can choose whatever target point we want.
 
Last edited:

Jimster480

Major Contributor
Patreon Donor
Joined
Jan 26, 2018
Messages
1,039
Likes
548
Location
Miami
#54
I read about this review on another forum, that's why I signed up and that's why this is my first post here. I own a TDAI-3400 so everything that is written about it has my special interest.. ;)

@amirm my first reaction after reading your review was, could it be that you had a faulty unit on hand? Especially because some (unexpected) outcomes only concerned one channel. Did you confront/consult Lyngdorf about your findings?

Secondly, I think it is a strange decision to review this unit as a 'traditional' DAC. Almost no-one will use a TDAI-3400 as a DAC to drive an (analogue input) amplifier. I think that - given the concept - it is not strange that the output stage / D-to-A is not of the highest quality. In 9 of the 10 instances these outputs will only be used to drive subwoofers via its cross-over function. The TDAI-3400 is essentially a powerDAC and excels in driving speakers via its speaker outputs. I actually compared the TDAI-3400 to NCore, Ayre, Devialet amongst others and preferred it. By ear but nonetheless.

That said, I use (and love it) as an amplifier, very good DRC and as a cross-over but I drive it counterintuitive with a Chord DAVE via its very high quality analogue inputs (optional module). This easily bests feeding the TDAI a digital signal. Best digital inputs by the way are AES/EBU and S/PDIF. USB and ethernet are not best-in-class so not strange that your test via USB did not measure well.

Lastly, I wonder if it could be that the Lyngdorf ICC (Inter-sample Clipping Correction) function did blur your outcomes and measurements. In my (very resolving) setup ICC 'enabled' degrades the SQ. I notice a relay switching when toggling this function so I suspect that ICC puts extra electronics in the pathway. Also the subsonic filter that Lyngdorf implemented could be a factor. Both ICC and the subsonic filter are enabled after a factory reset, as you did.
Welcome to the forum!

If you check the whole list of measurements then you will see that he also tested using AES / RCA input with no better performance.
Infact the measured performance with the RCA inputs were worse than before.
I suppose checking into the ICC is something Amir will do but... he wasn't near clipping levels anyway and it looks as if they are converting all samples to digital in memory.
 

cjfrbw

Senior Member
Joined
Mar 5, 2018
Messages
303
Likes
261
#55
Maybe the manufacturers will pay Amir NOT to measure their products. "I have the measurements, and they are not looking good!" "The check is in the mail."
 

gvl

Major Contributor
Joined
Mar 16, 2018
Messages
1,123
Likes
650
Location
SoCal
#56
Maybe the manufacturers will pay Amir NOT to measure their products. "I have the measurements, and they are not looking good!" "The check is in the mail."
Bingo, extortion was Amir's business plan all along.
 
Last edited:

garbulky

Addicted to Fun and Learning
Joined
Feb 14, 2018
Messages
828
Likes
227
#57
Not that I have seen. There is no standard or even convention for using such THD rates. Power is everything in marketing of amplifiers and rates distortion ranges from no mention to anything they want to use. To wit, the Lyngdorf in review here has no indication:

View attachment 21949

Here is Schiit:

View attachment 21950

So no, there is no such standard and hence justification for me to do it.

We are much better off encouraging the industry to publish power spec at the design limit as I am doing than using high THD numbers.

What do we do if an amp has no hockey stick by the way? That is, it is distortion-less to the limit. You want to put that in a table at the same power level but 1% THD for others? My scheme allows for that for publishing power before large amount of distortion sets in.
Perhaps use both sentences? The knee rating and a 0.1% or 1% THD rating.
If there is an amp with no hockey stick, then it should be mentioned. And it would show up likely in distortion measures. If I had to guess you aren't going with 0.1% THD because that's too high for your transparency standards?
I'm not sure why you feel such low thd values are the design limit. How useful is this information in real use? They are clearly putting out some nice low distortion power above the design limit. It looks to me like that's the lowest distortion the amp can do. Not necessarily its limit of clean power.


Though they may vary slightly with their stated output. No amp company I know of is advertising their power at 0.003% THD or lower because of a knee. I've never seen max power rated at lowest thd possible.

When one may get even 50 more watts of power at still very low levels of thd, people would like to know that.

Does that make sense why that feels less useful to mention that?
Here are some companies that rate the THD at close to 0.1% or 1%

Emotiva:
Audio Specifications (Three High-Powered Single Channel Modules):
  • Power Output:
    300 watts RMS/channel; 20 Hz – 20 kHz; THD<0.1%; 8 Ohms; one channel driven.
    550 watts RMS/channel; 20 Hz – 20 kHz; THD<0.2%; 4 Ohms; one channel driven.
    300 watts RMS/channel; THD<0.1%; 8 Ohms; two channels driven.
    490 watts RMS/channel; THD<0.1%; 4 Ohms; two channels driven.
    275 watts RMS/channel; THD<0.1%; 8 Ohms; ALL THREE channels driven.
Pass Labs:
Technical specifications
Power Output/ch (8 ohm)
150
Distortion, (1 KHz, full power)

Yamaha
Rated Output Power (1kHz, 2ch driven) 165 W (8 ohms, 0.9% THD)

Pioneer Elite avr
Power Output: Watts per Channel (20 Hz – 20 kHz, THD 0.08 % @ 8 ohms FTC)80 W/ch
Power Output: Watts per Channel (4 ohms, 1 kHz, 1 %, 2 ch Driven)

Mark Levinson
RATED OUTPUT POWER
250 wpc RMS @ 8Ω, 20Hz to 20kHz @ <0.3% THD, full output from 2.83VRMS

Denon
Output power 4 Ohm (1 kHz, T.H.D. 0.7%)
85 W + 85 W
 
Last edited:

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
19,492
Likes
20,590
Location
Seattle Area
#59
Perhaps use both sentences? The knee rating and a 0.1% or 1% THD rating.
If there is an amp with no hockey stick, then it should be mentioned. And it would show up likely in distortion measures. If I had to guess you aren't going with 0.1% THD because that's too high for your transparency standards?
I'm not sure why you feel such low thd values are the design limit. How useful is this information in real use? They are clearly putting out some nice low distortion power above the design limit. It looks to me like that's the lowest distortion the amp can do. Not necessarily its limit of clean power.
0.1% translates to a SINAD of 60 dB so yes, that is definitely not a useful target to me.

Any extra test I have to run takes away time from reviewing something else. So strong justification is needed for me to do more work. The information you want is on the graph.
 

restorer-john

Major Contributor
Joined
Mar 1, 2018
Messages
2,057
Likes
3,052
Location
Gold Coast, Queensland, Australia
#60
Though they may vary slightly with their stated output. No amp company I know of is advertising their power at 0.003% THD or lower because of a knee. I've never seen max power rated at lowest thd possible.
You need to peruse more specifications, as that statement is largely incorrect.

Much of the better quality gear made through the 80s and 90s specified their THDs typically around the 0.003%-0.005%, 20Hz-20KHz, both channels driven from 250mW to full rated power. Those numbers were well below the so-called 'knee' and pretty much at the bottom of their downward slope.
 
Top Bottom