Audio science review Schiit Midgard headphone amp and preamp
This is a review, listening tests and detailed measurements of the Schiit Midgard balanced headphone amplifier and preamp. It was sent to me by the company .
While I am not a fan of the symbols Schiit uses instead of proper labels, there are only two to learn which is no big deal (input and gain). Both XLR and 1/4 are provided by power output remains the same. Company says the XLR output is superior due to inclusion of the load in the feedback loop. The design is discrete.
Back panel has what you expect:
Power switch forever seems to stay in the back on Schiit products despite lower usability.
Schiit Midgard Headphone Amp Measurements
For testing I focused on XLR input but did test both 1/4 and XLR outputs. Here they are:
As noted, there is no measurable difference between the two. I stayed with XLR output for the rest of the test just in case. As is, performance is near state of the art as the company transparently states:
EDIT: it was requested that I test RCA Input:
Overall performance remains the same but distortion actually goes down relative to XLR!
Distortion is below threshold of hearing as is noise at full 4 volt output:
On the right though, we are short of that transparency. Getting there requires negative gain which the amp does not have:
Still, this is above average performance.
Multitone shows extremely low level of distortion:
As does wideband THD+N vs frequency:
Frequency response is as flat and as wide as you would ever want it to be:
Channel balance is surprisingly good for an analog pot:
Most important test here is power and the Midgard has plenty of it:
The amp does get unhappier at lower impedances though:
Protection circuit kicks in before the amp even clips at lower impedances! Seems like it could have been a bit more relaxed than it is. Still, worst case distortion before any clipping is extremely low so I don’t expect any audible issue at any impedance before the limit sets in.
EDIT: ran an acoustic distortion measurement using Sennheiser HD-650 headphone, comparing the output using XLR and 1/4 jacks:
There is really no reliable difference.
Schiit Midgard Headphone Amp Listening Test
As usual I start with my everyday Dan Clark Stealth headphone which is a low impedance and difficult to drive unit. Testing in high gain I was able to push them to point of ear lobe resonance (!) at 3:00pm on the volume control (high gain). Anything higher than that would cause severe distortion but you wouldn’t want to go there anyway. Below that level the sound was superb with nothing to complain about.
Switching to Sennheiser HD650 which is 300 ohm and much more sensitive resulted in same sensation of resonance and immense power at just 12:00 o’clock. Such high-power amps really bring out the bass out of this headphone and result in melt in your chair performance. Shame there is a risk of hearing damage!
With both headphones I tried to compare 1/4 to XLR. With Dan Clark I thought 1/4 was a bit better. With HD650, the XLR. Both differences were subtle enough to easily blame on sighted bias. Indeed, I stayed with 1/4 with HD650 and found the experience superb so there wasn’t more to be wanted anyway.
Conclusions
I continue to be impressed by Schiit’s ability to keep up with far east manufacturers on both performance and pricing. It seems that it shouldn’t be possible but they keep doing it. Yes, measured noise and distortion is a bit below state of the art, but certainly good enough for transparency. Add to that ton of power and you have the makings of a enjoyable and capable headphone amplifier. The look of the unit is nice as well as are controls.
I am going to add Schiit Midgard to my recommended list.
EDIT: video review just posted as well:
Manufacturer Specifications:
Frequency Response: 20Hz-20Khz, +/-0.01dB
Output Power
Maximum Power, 16 ohms: 5.5W RMS per channel
Maximum Power, 32 ohms: 4.8W RMS per channel
Maximum Power, 50 ohms: 3.2W RMS per channel
Maximum Power, 300 ohms: 750mW RMS per channel
Maximum Power, 600 ohms: 375mW RMS per channel
THD+N
Low Gain: Less than 0.0001% (-118dB) at 4V RMS into 300 ohms
High Gain: Less than 0.0003% (-108dB) at 4V RMS into 300 ohms
IMD
Low Gain: Less than -112dB at 4V RMS into 300 ohms, CCIF
High Gain: Less than -110dB at 4V RMS into 300 ohms, CCIF
SNR
Low Gain: Greater than 128dB, referenced to 4V RMS
High Gain: Greater than 118dB, referenced to 4V RMS
Crosstalk
Less than -80dB, 20 Hz-20 kHz, 300 ohm load
Output Impedance
SE ¼” TRS output: less than 0.1 ohms
Neutrik 4-pin XLR output: approximately 2 ohms
Preamp output: 75 ohms
Input Impedance: 50k ohms
Gain: 1 (0db) or 5 (14db)
Topology: Fully discrete, DC coupled, highly linear open-loop with low loop feedback, Halo™ topology mixed-mode feedback for Neutrik 4-pin output
Protection: Failsafe DC power input and muting relay, overcurrent sensing and output lift
Power Supply: “Wall wart” style 14-16VAC transformer, stacked rails of +/-20V and +/-30V regulated voltage rails, 10,000uF total capacitance
Power Consumption: 3W idle, 16W max
Size: 9 x 6 x 1.5”
Weight: 2 lb