This is a review and detailed measurements of a "vintage" (1990) Aragon 2004 MKII stereo amplifier. It is on kind loan from a member.
I like the v-shaped design to set it apart from countless other boxes. Speaking of boxes, this thing is massive. It was designed to house the double power 4004 version with the same power supply. Inside is dusty and I am not sure if it has been refurbished or not.
If anyone knows what it sold for originally please, post.
Reading online, it is claimed that Dan D'Agostino of Krell and now D'Agostino amplifier company fame did a lot of the electronic design.
Note: please ignore the "4004" designation on the graphs. I originally thought it was that unit and didn't realize otherwise until the end of the measurements.
Aragon 2004 MK II Measurements
Warm up was uneventful and is often the case, performance got (negligibly) worse, not better, contrary to popular opinion:
Here is our usual dashboard of pushing a 1 kHz tone into the amplifier:
There is a ton of power supply related noise. So I shut off the input and saw some amount of it still there:
More on this later. For now, SINAD of 65 dB is well below the average of all amplifiers tested to date (around 79 dB). Dominant distortion spikes are 2nd and 4th.
Dynamic range is actually very good:
Crosstalk is not:
Swinging the other end again, frequency response is nice, flat and extended:
Multitone shows a lot of distortion spikes which is likely a combination of power supply noise and intermodulation:
Here is distortion+noise vs output power:
As you see from our two reference amplifiers (dashed lines), the usual slope is pointing down. This is because noise dominates the measurements when output power is low but once we increase the output signal, it progressively becomes smaller and smaller part of the original signal so overall performance improves. Not here. The line is flat. My best guess is that power supply noise is proportionally increasing with output power. So likely the filter capacitors are not doing their job. It could be an original problem or due to them aging.
Same is true of 8 ohm load:
Allowing for a bit more distortion, power specs are met:
Changing the frequency and making the same power measurements we get:
Distortion lines for 1 kHz and lower are actually above their higher frequency counterparts. This is backward of most amplifiers and again points to power supply producing more noise as lower frequencies rely on them more.
Conclusions
At first I thought that an amplifier produced in 1990 would not be "vintage" but then realized that was 30 years ago! Time flies as they say... It is hard to know if this amplifier is running at original spec. I did not get any information from the member on that front. Looking inside, it is dusty and components appear to be original but I could not look closely. As is, performance is not special. There is a lot of distortion and classic tests like crosstalk show weakness. So I would not go out of my way to get one unless you have massive space you want to fill with a big box amplifier.
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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/
I like the v-shaped design to set it apart from countless other boxes. Speaking of boxes, this thing is massive. It was designed to house the double power 4004 version with the same power supply. Inside is dusty and I am not sure if it has been refurbished or not.
If anyone knows what it sold for originally please, post.
Reading online, it is claimed that Dan D'Agostino of Krell and now D'Agostino amplifier company fame did a lot of the electronic design.
Note: please ignore the "4004" designation on the graphs. I originally thought it was that unit and didn't realize otherwise until the end of the measurements.
Aragon 2004 MK II Measurements
Warm up was uneventful and is often the case, performance got (negligibly) worse, not better, contrary to popular opinion:
Here is our usual dashboard of pushing a 1 kHz tone into the amplifier:
There is a ton of power supply related noise. So I shut off the input and saw some amount of it still there:
More on this later. For now, SINAD of 65 dB is well below the average of all amplifiers tested to date (around 79 dB). Dominant distortion spikes are 2nd and 4th.
Dynamic range is actually very good:
Crosstalk is not:
Swinging the other end again, frequency response is nice, flat and extended:
Multitone shows a lot of distortion spikes which is likely a combination of power supply noise and intermodulation:
Here is distortion+noise vs output power:
As you see from our two reference amplifiers (dashed lines), the usual slope is pointing down. This is because noise dominates the measurements when output power is low but once we increase the output signal, it progressively becomes smaller and smaller part of the original signal so overall performance improves. Not here. The line is flat. My best guess is that power supply noise is proportionally increasing with output power. So likely the filter capacitors are not doing their job. It could be an original problem or due to them aging.
Same is true of 8 ohm load:
Allowing for a bit more distortion, power specs are met:
Changing the frequency and making the same power measurements we get:
Distortion lines for 1 kHz and lower are actually above their higher frequency counterparts. This is backward of most amplifiers and again points to power supply producing more noise as lower frequencies rely on them more.
Conclusions
At first I thought that an amplifier produced in 1990 would not be "vintage" but then realized that was 30 years ago! Time flies as they say... It is hard to know if this amplifier is running at original spec. I did not get any information from the member on that front. Looking inside, it is dusty and components appear to be original but I could not look closely. As is, performance is not special. There is a lot of distortion and classic tests like crosstalk show weakness. So I would not go out of my way to get one unless you have massive space you want to fill with a big box amplifier.
-----------
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/