This is a review and detailed measurements of the Niles SI-2150 Class D amplifier. It is on kind loan from a member. He purchased it refurbished and I see it for sale at $367. Original cost seems to be US $850.
By using efficient Hypex UcD250LP class D amplifier modules, the SI-2150 manages to fit in a small, 1U rack chassis:
Niles is targeting this amp as Custom Integration (CI) channel so has good control as far as trigger and such:
In use, the unit stayed cool and calm. When pushed into clipping it will go into protection. Sadly it stays in that mode until it is power cycled rather than recovering on its own.
Nice set of gain controls are provided which lets you get precise channel matching -- something that is rarely the case in many amplifiers. I set them to 29 dB for my testing.
Amplifier Audio Measurements
As usual we start with our 1 kHz tone dashboard into 4 ohm load:
SINAD which is the ratio of distortion and noise versus signal is better than average at 85 dB:
Signal to noise ratio ranks in the same region:
Frequency response is flat enough in audible band:
Power into 4 ohm shows good noise and distortion:
Lots of power is available if we allow the distortion to rise to 1%:
Response into 8 ohm load is rather odd:
Usually we have a declining graph with hard clipping in solid state amplifiers, not this gradual rise in distortion. As such, it was not easy to determine the clipping point as I normally do.
Typical of class D amps, the relationship with frequency and power is complex:
Removing my ultrasonic filter allows us to see the switching spectrum of the amplifier:
Conclusions
I am not sure at the regular list price but at refurbished cost, this is a steal of an amplifier. Lots of power in a cool, small enclosure with above average distortion and noise.
I am going to put the Niles SI-2150 on my recommended list.
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As always, questions, comments, recommendations, etc. are welcome.
Don't have an ounce of creativity at the moment to tell you anything sarcastic. So let's cut to the chase and ask you to donate what you can using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
By using efficient Hypex UcD250LP class D amplifier modules, the SI-2150 manages to fit in a small, 1U rack chassis:
Niles is targeting this amp as Custom Integration (CI) channel so has good control as far as trigger and such:
In use, the unit stayed cool and calm. When pushed into clipping it will go into protection. Sadly it stays in that mode until it is power cycled rather than recovering on its own.
Nice set of gain controls are provided which lets you get precise channel matching -- something that is rarely the case in many amplifiers. I set them to 29 dB for my testing.
Amplifier Audio Measurements
As usual we start with our 1 kHz tone dashboard into 4 ohm load:
SINAD which is the ratio of distortion and noise versus signal is better than average at 85 dB:
Signal to noise ratio ranks in the same region:
Frequency response is flat enough in audible band:
Power into 4 ohm shows good noise and distortion:
Lots of power is available if we allow the distortion to rise to 1%:
Response into 8 ohm load is rather odd:
Usually we have a declining graph with hard clipping in solid state amplifiers, not this gradual rise in distortion. As such, it was not easy to determine the clipping point as I normally do.
Typical of class D amps, the relationship with frequency and power is complex:
Removing my ultrasonic filter allows us to see the switching spectrum of the amplifier:
Conclusions
I am not sure at the regular list price but at refurbished cost, this is a steal of an amplifier. Lots of power in a cool, small enclosure with above average distortion and noise.
I am going to put the Niles SI-2150 on my recommended list.
------------
As always, questions, comments, recommendations, etc. are welcome.
Don't have an ounce of creativity at the moment to tell you anything sarcastic. So let's cut to the chase and ask you to donate what you can using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
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