This is a review and comparison of Schiit Lyr tube Headphone amplifier to Schiit Magni 3. The Schiit Lyr is on kind loan from a member. It is discontinued but seems to have retailed for US $450 (replaced with Schiit Lyr 2). The Schiit Magni 3 which is a solid-state headphone amplifier retails for $99 so quite a bit cheaper.As you see above, there is quite a bit of size difference. There are after-market tube socket risers in the Lyr to make it easier to "roll" (swap) tubes. The unit came with a set of GE tubes 6BQ7A dual-triodes ( http://www.nj7p.org/Tubes/PDFs/Frank/093-GE/6BQ7A.pdf ) and another pair of aftermarket Russian Genalex Gold Lion E88CC / 6922 replacements ( https://www.tubedepot.com/products/genalex-gold-lion-e88cc-6922-preamp-vacuum-tube ). I could not find any specs on them but they were in boxes which indicates testing and classification of performance.Let's see how the two did in measurements. Normally I would send you to my tutorial on audio measurements ( https://www.audiosciencereview.com/forum/index.php?threads/understanding-audio-measurements.2351/ ) but these tests are rather new. Usually I am digitally generating data for DACs and such to convert to analog. But since these amplifiers are analog in, analog out, I used the analog output of my Audio Precision analyzer and created a few new tests. Over time I will update my tutorial and refine the tests.Let's start easy with wide-bandwidth frequency response test (to 48 kHz) at different volume level:Response is nicely flat but channel matching differs depending on volume. I am not showing the Magni 3 but it too had flat response to 48 kHz but with more channel imbalance.Next let's measure the output impedance:The Schiit Magni 3 does very well and the Lyr trails it by a bit with 1.6 ohm output impedance.Now let's look at how much power each can put out relative to amount of distortion first with 33 ohm dummy load:Until hard clipping at 1.5 watts, the Schiit Magni 3 has lower distortion. Clipping in Lyr is softer and output power is higher at clipping point (4.7 watts). At the same power though, let's say 1 watt, the Magni 3 is much cleaner than Lyr.Repeating the test at 300 ohm we get:Magni 3 again pulls ahead with far lower distortion. Yes, if you need more than it can output, the Lyr may be better but that margin of extra usable power is small. I did not need more power than either amplifier could output to my least efficient load, the Sennheiser HD-650.Using real headphones as loads, we get this busy chart:Everything below double yellow line is Magni 3, and above it is Lyr. As we see, the KZ IEMs which their very low impedance gave some heartburn to Magni 3 but even there, its distortion is lower than the best Lyr can achieve.The Lyr distortions are not only higher but also very different for each frequency. I measured and remeasured to be sure and that is what came out. You have to shake your head as to any notion of "high fidelity" with these kinds of numbers and wild response.Let's look at crosstalk or how much channel separation we have:I think the humps at low frequencies is power supply hum that is confusing the analyzer into thinking there is crosstalk. Otherwise the Magni 3 response is fine. Audibly the Lyr is OK too be from measurement point of view, it is far worse. And uneven between the two channels to boot.Now let's look at linearity which some of you are familiar with from my DAC tests:On the left is what my Audio Precision Analyzer can do when you connect its output to input. As you see, it is darn near perfect even though this box was designed some 20 years ago! Compared to that the Schiit Magni 3 does OK but loses linearity at around -101 dB. At higher amplitudes the error is due to clipping.The Schiit Lyr runs off the rails at 16 bits, most likely due to high levels of hum and noise (see subjective listening tests). Note that this test is with the aftermarket Genalex tubes which produced lower distortions.Edit: per request later in the thread, here is the noise and jitter spectrum of a 1 kHz tone:As we see, there is nothing good about Lyr distortion profile. It simply has a lot more of what Magni has plus fair bit higher noise floor.I have more measurements but I think the picture is clear. As one would expect, these tube amplifiers have no prayer of matching the objective performance of solid state amplifiers. Not mentioned above is the variability. Warm-up was a major factor here with tests not being reliable in the first 15 minutes or so of operation (the data is for much longer warm up time above).Advocates of tube products say the pudding is in listening tests so let's get into that. Note that my listening test report here is with the stock GE tube. I also tested the Genalex but did not take notes.All tests are level matched using 1 kHz tone. Both amps were driven simultaneously using split Y RCA cables. The output went into an AB box allowing me to perform rapid AB switching (or not). Forget about doing this test without level matching. The outcome would be completely corrupt. Likewise, the differences were small enough that plugging and unplugging headphones from one unit to the other would also corrupt the results. At least initially until you hear the difference/train your ears.I started my testing with the Kz ATE IEMs. With these, the Lyr was a buzz factory. I mean real loud buzzing. I did a bit of testing anyway and thought I liked the Lyr a bit better. The extra buzz seem to accentuate the highs a bit.Next I tried the Sony MDRV6. These too were sensitive enough to allow the buzz to be heard but not nearly as much as KZ ATE IEMs. Still no blind testing was possible so I moved on.The results with HiFiman and Sennheiser HD-650 were similar: the Lyr seemed to accentuate the highs at first. Focusing more on those notes, it became clear that they were being distorted. And it was that distortion that emphasized the highs. High-pitch transients would get hissy and longer. Not realizing that would make one think the sound is more "open."The above difference was small though as I mentioned in the preface. Casual listening would render both of them as being equal. I did not sense any modification of headphone frequency response due to higher output impedance of Lyr.I will perform a teardown of both Lyr and Magni amplifiers later. But for now, wanted to note a few bothersome things. The Lyr arrived with its volume knob loose. It has a single screw which mates with a perfectly round potentiometer shaft. Translation: it is always going to come loose. The shaft has a slot at the end and the knob needs to have a corresponding fin to go in it to keep it from becoming loose. That would complicate its machining a ton but hey, they get paid to solve these problems!On Schiit Magni 3, the darn thing really lives up to its name. When I was testing it with my new dummy load, all of a sudden I see smoke pouring out of it!!! I immediately turned it of. I then turned it back on and it still worked! Not sure what made it upset other than the fact that if you are driving it, when you unplug it the headphones, you still hear your output through some kind of mechanical resonance! It is quite uncanny. It would do this for 2-3 seconds before fading to nothing.When using a sensitive headphone like the KZ, if I turned the volume up and down, I could hear noise through one channel of the headphone in the last quarter of its turn.My personal reference headphone system is Stax SRM-007t which is differential tube amplifier. So I don't have a bias against tube audio in general. In this case though, for the life of me I can't figure out why anyone would want to buy the Schiit Lyr. Yes, it has more power due to higher output voltage but it also produces copious amount of measured distortion and some audible one. Combine that with much higher cost and cost of ownership in tubes and it just makes no sense to me.If you want tube coloration, get one that gives you that. This Schiit Lyr doesn't do that in my somewhat casual listening tests, leaving me with nothing to hang my hat on.The Schiit Magni 3 performed well relative to its tube brother. Until I test more devices against it, I don't have a recommendation to offer for it. The price is super attractive but quality issues above remains a concern.As always, questions, comments, corrections, jokes, etc. are all welcome!----If you like this review, please consider donating funds for these types of hardware purchase using Patreon ( https://www.patreon.com/audiosciencereview ), or upgrading your membership here though Paypal ( https://audiosciencereview.com/foru...eview-and-measurements.2164/page-3#post-59054 ).