This is a review and detailed measurements of the Down4Sound JP95 4/1 channel car audio amplifier. It is on kind loan from a member and is on sale for $250.
This is a massive amplifier with incredibly beefy terminals and many features. I am shocked that it sells for just $250.
I configured the amplifier for 4 channel use and defeated all the filters I could. Alas, it seems the main channels always have a high pass with a minimum of 20 Hz (see measurements). Testing is focused on Channels 1 and 2.
Power was provided by a custom Lithium back with capacity of 300 amp hour and peak current above that. Lab supply was used to augment the battery bank as needed (I checked and it had little impact on measurements).
Down4Sound JP95 Amplifier Measurements
As usual, we start with our 5 watts test into 4 ohm load:
Distortion is actually kind of reasonable at -92 dB. It is the noise that is the problem, taking SINAD way down to just 71 dB or so. Average for all amplifiers (almost all home systems) is about 80 dB so this is below average by our standards. You can see the poor residual noise in SNR test:
Fortunately at full power, you almost approach CD's 16 bit dynamic range. Just be careful about using sensitive tweeters with this as you are likely to hear a hiss.
Frequency response shows typical budget class D implementation load (speaker) impedance dependency:
Even at 1 KHz there is an effect so you better EQ your system and dial that out. As noted, there is bass roll off which I guess is fine if you are using a sub with this anyway.
Distortion is actually the best at our 1 kHz test tone above. Below and above, it rises significantly:
Resulting in very poor showing at 19 & 20 kHz:
Crosstalk is very bad as well:
We can see the high noise floor again in our power sweep:
Usually I measure clipping at very conservative points in the graph. Here I gave it the benefit of doubt to get the 122 watts. If I go by 1% THD, we get less power:
Same issues with 8 ohm:
Sweeping frequencies we see that the transfer function is quite odd at times:
Finally, the amp needed a couple of minutes to stabilize:
Conclusions
Objective measurements can best be translated into: "it could be worse" given the mess that goes on in car audio world. Normally this would raise my ire but at $250, it is really hard to complain about such a stout, 4 channel amplifier with a ton of functionality.
Personally I can't recommend the Down4Sound JP95 amplifier. But your mileage may vary if cost, features and good cooling is high priority for you.
------------
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/
This is a massive amplifier with incredibly beefy terminals and many features. I am shocked that it sells for just $250.
I configured the amplifier for 4 channel use and defeated all the filters I could. Alas, it seems the main channels always have a high pass with a minimum of 20 Hz (see measurements). Testing is focused on Channels 1 and 2.
Power was provided by a custom Lithium back with capacity of 300 amp hour and peak current above that. Lab supply was used to augment the battery bank as needed (I checked and it had little impact on measurements).
Down4Sound JP95 Amplifier Measurements
As usual, we start with our 5 watts test into 4 ohm load:
Distortion is actually kind of reasonable at -92 dB. It is the noise that is the problem, taking SINAD way down to just 71 dB or so. Average for all amplifiers (almost all home systems) is about 80 dB so this is below average by our standards. You can see the poor residual noise in SNR test:
Fortunately at full power, you almost approach CD's 16 bit dynamic range. Just be careful about using sensitive tweeters with this as you are likely to hear a hiss.
Frequency response shows typical budget class D implementation load (speaker) impedance dependency:
Even at 1 KHz there is an effect so you better EQ your system and dial that out. As noted, there is bass roll off which I guess is fine if you are using a sub with this anyway.
Distortion is actually the best at our 1 kHz test tone above. Below and above, it rises significantly:
Resulting in very poor showing at 19 & 20 kHz:
Crosstalk is very bad as well:
We can see the high noise floor again in our power sweep:
Usually I measure clipping at very conservative points in the graph. Here I gave it the benefit of doubt to get the 122 watts. If I go by 1% THD, we get less power:
Same issues with 8 ohm:
Sweeping frequencies we see that the transfer function is quite odd at times:
Finally, the amp needed a couple of minutes to stabilize:
Conclusions
Objective measurements can best be translated into: "it could be worse" given the mess that goes on in car audio world. Normally this would raise my ire but at $250, it is really hard to complain about such a stout, 4 channel amplifier with a ton of functionality.
Personally I can't recommend the Down4Sound JP95 amplifier. But your mileage may vary if cost, features and good cooling is high priority for you.
------------
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/
