This is a review and detailed measurements of the Darlington Labs MM-5 Moving Magnet phono pre-amplifier. It was kindly purchased new by a member and drop shipped to me. It has a few options but as purchased, it costs US $199 from the company.
The front panel doesn't look half bad for a budget device:
The back side, not so much:
While the RCA connectors are high quality, the labeling and input power hole are as Dave Jones would say, "how you doing."
I must confess the name Darlington takes me back decades to my childhood when I was learning electronics. Darlington is a simple pairing of two transistors where their gain multiplies almost like magic. I would always have a smile on my face when I would spot it in a circuit diagram.
Here, I am not sure if any Darlington circuit is used or not. Company says it uses J-FET discrete class A amplifier with no feedback. I suspect we are going to see plenty of distortion.
Darlington Labs MM-5 Measurements
With only moving magnet supported, our job here is pretty simple as far as measurements starting with our dashboard:
We have two problems here. One is mains and harmonics which I could not get to change one bit no matter how I grounded things. And quite high second harmonic distortion as we expected. Ranking therefore is quite low:
Company makes up for that partially with good implementation of RIAA equalization:
As noted, there is no high pass filter here so if your woofers are dancing around without making any sound, you know you should have gotten a phono stage with one.
I was really impressed by the high level of headroom available:
Immunity to pops and clicks should be good then.
What distortion there is, is almost constant with frequency which is good:
Conclusions
A design choice was made to leave feedback behind which then resulted in quite elevated distortion. Usually we don't see any distortion spikes in decently implemented phono stages with SINAD completely dominated by noise. Not here. There is plenty of distortion but it is second order so maybe folks can feel good about that. Given the high distortion of the LP media itself, I decided to not be too critical of that and assign some weight to nice headroom and decent RIAA implementation.
Of note, company provides pretty accurate measurements that correlate well with mine. Kudos on that.
Personally I can't recommend the Darlington Labs MM-5. You can choose otherwise with the data provided.
-----------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
The front panel doesn't look half bad for a budget device:
The back side, not so much:
While the RCA connectors are high quality, the labeling and input power hole are as Dave Jones would say, "how you doing."
I must confess the name Darlington takes me back decades to my childhood when I was learning electronics. Darlington is a simple pairing of two transistors where their gain multiplies almost like magic. I would always have a smile on my face when I would spot it in a circuit diagram.
Here, I am not sure if any Darlington circuit is used or not. Company says it uses J-FET discrete class A amplifier with no feedback. I suspect we are going to see plenty of distortion.
Darlington Labs MM-5 Measurements
With only moving magnet supported, our job here is pretty simple as far as measurements starting with our dashboard:
We have two problems here. One is mains and harmonics which I could not get to change one bit no matter how I grounded things. And quite high second harmonic distortion as we expected. Ranking therefore is quite low:
Company makes up for that partially with good implementation of RIAA equalization:
As noted, there is no high pass filter here so if your woofers are dancing around without making any sound, you know you should have gotten a phono stage with one.
I was really impressed by the high level of headroom available:
Immunity to pops and clicks should be good then.
What distortion there is, is almost constant with frequency which is good:
Conclusions
A design choice was made to leave feedback behind which then resulted in quite elevated distortion. Usually we don't see any distortion spikes in decently implemented phono stages with SINAD completely dominated by noise. Not here. There is plenty of distortion but it is second order so maybe folks can feel good about that. Given the high distortion of the LP media itself, I decided to not be too critical of that and assign some weight to nice headroom and decent RIAA implementation.
Of note, company provides pretty accurate measurements that correlate well with mine. Kudos on that.
Personally I can't recommend the Darlington Labs MM-5. You can choose otherwise with the data provided.
-----------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/