This is a review and detailed measurements of the HeadAmp Gilmore Lite mk2 headphone amplifier. It is on kind loan from a member and costs US $499 from the company direct.
In a sea of same looking black boxes, the Gilmore Lite manages to look distinct:
The volume control color doesn't match the matt finish of the rest of the unit but feels very good. Note that there is no gain selection. The switch on the right allows selection of one of two inputs in the back instead:
A massive and beefy AC transformer provides +-15 volts AC but at just 1/4 of an amp. This means low impedance loads may provide some limitation.
HeadAmp Gilmore Lite mk2 Measurements
As usual, we feed headphone amps 2 volts in and set the volume control to get the same voltage out (for balanced units I use 4 volts):
The Gimore Lite uses class A amplification which makes people think it has lower distortion but such is not the case here. We have distortion products reaching up to -88 dB which is decades worse than best in class products we test (at much lower prices):
Signal to noise ration is good enough at 2 volts out but not at 50mv:
Lack of gain control hurts the design when producing very low outputs so you may experience some noise with very sensitive IEMs.
Power is everything in headphone amps so let's measure that starting with high impedance of 300 ohms:
My threshold here is 100 milliwatts and the Gilmore struggles to get there even for allowing for much rise in distortion.
Switching to 32 ohm we get:
Fortunately in both cases noise is kept under control before distortion sets in which occurs very early.
I have a new test which shows the output voltage at a number of impedances. You can convert them to watts using the formula power = Voltage * Voltage/Load resistance:
Nice to see that it can handle even 12 ohm load but distortion rise as the load impedance reduces is quite significant.
Frequency response while not as flat as some competitors, is certainly more than good enough:
Finally, I was impressed with how accurate channel matching was as I was rotating the volume control:
If they are all like this, this could be a rather unique asset of the Glimore Lite.
Headphone Amp Listening Tests
As usual I start with my tough to drive, low impedance Ether CX headphone. The Gilmore Lite managed to drive it well, distorting toward the last 25% of the volume range. By then though it was too loud to listen to it. Same happened with the Sennheiser HD650. I detected no magic related to Class A implementation or any other. It sounded very good until it got distorted at extreme volumes.
Conclusions
The developments in the last 18 months in headphone amplifiers has turned the market upside down. We can now get units that have more power than you can use with distortion levels so far below hearing threshold that I call them "instrument grade." Classic designs like Gilmore Lite mk2 are simply not a player there. Objectively this unit is a loss. Fortunately the ears are not as critical as they eye looking at measurements so subjectively the performance is there if you don't ask it to get crazy loud.
Given the many wonderful choices in the market, I cannot recommend the HeadAmp Gilmore Lite mk2. If you own it though, it is a fine choice and I would not run out and get something else.
------------
As always, questions, comments, recommendations, etc. are welcome.
Appreciate any donations using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
In a sea of same looking black boxes, the Gilmore Lite manages to look distinct:
The volume control color doesn't match the matt finish of the rest of the unit but feels very good. Note that there is no gain selection. The switch on the right allows selection of one of two inputs in the back instead:
A massive and beefy AC transformer provides +-15 volts AC but at just 1/4 of an amp. This means low impedance loads may provide some limitation.
HeadAmp Gilmore Lite mk2 Measurements
As usual, we feed headphone amps 2 volts in and set the volume control to get the same voltage out (for balanced units I use 4 volts):
The Gimore Lite uses class A amplification which makes people think it has lower distortion but such is not the case here. We have distortion products reaching up to -88 dB which is decades worse than best in class products we test (at much lower prices):
Signal to noise ration is good enough at 2 volts out but not at 50mv:
Lack of gain control hurts the design when producing very low outputs so you may experience some noise with very sensitive IEMs.
Power is everything in headphone amps so let's measure that starting with high impedance of 300 ohms:
My threshold here is 100 milliwatts and the Gilmore struggles to get there even for allowing for much rise in distortion.
Switching to 32 ohm we get:
Fortunately in both cases noise is kept under control before distortion sets in which occurs very early.
I have a new test which shows the output voltage at a number of impedances. You can convert them to watts using the formula power = Voltage * Voltage/Load resistance:
Nice to see that it can handle even 12 ohm load but distortion rise as the load impedance reduces is quite significant.
Frequency response while not as flat as some competitors, is certainly more than good enough:
Finally, I was impressed with how accurate channel matching was as I was rotating the volume control:
If they are all like this, this could be a rather unique asset of the Glimore Lite.
Headphone Amp Listening Tests
As usual I start with my tough to drive, low impedance Ether CX headphone. The Gilmore Lite managed to drive it well, distorting toward the last 25% of the volume range. By then though it was too loud to listen to it. Same happened with the Sennheiser HD650. I detected no magic related to Class A implementation or any other. It sounded very good until it got distorted at extreme volumes.
Conclusions
The developments in the last 18 months in headphone amplifiers has turned the market upside down. We can now get units that have more power than you can use with distortion levels so far below hearing threshold that I call them "instrument grade." Classic designs like Gilmore Lite mk2 are simply not a player there. Objectively this unit is a loss. Fortunately the ears are not as critical as they eye looking at measurements so subjectively the performance is there if you don't ask it to get crazy loud.
Given the many wonderful choices in the market, I cannot recommend the HeadAmp Gilmore Lite mk2. If you own it though, it is a fine choice and I would not run out and get something else.
------------
As always, questions, comments, recommendations, etc. are welcome.
Appreciate any donations using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
