incubus
Member
Acoustic Energy 100.2 bookshelf speaker review
Since this is my first post and my first measurement of a commercial speaker please be patient with me. English is not my mother language so my text might be bumpy to read.
I have built some speakers myself following guidelines from DIY Hifi magazines available in Germany. So far I am not very happy with the results so I started measuring my speakers.
But I am a beginner and I have found this forum and I am so happy to finally be able to move away from pure subjective description to objective measuring.
Again, this is my first analysis of a commercial speaker and I would be glad if you could give me additional advice on things I can improve.
Tempted by many positive online reviews I have bought a pair of Acoustic Energy speakers: AE 100.2 for 350 EUR (before I found this forum).
Let's find out if they are truly any good using the following tools:
SPL far field (1m):
I was measuring in my garden. The speaker box was 1.2 meters from the ground and the microphone was 1m from the speaker pointed at the tweeter.
The first graph represents the measurements without any smoothing, the second graph show psychoacoustic smoothing by REW. My neighbors are friendly people and I would like them to stay that way so I was aiming for roughly 80 db. I only have a Hifi amplifier so I cannot tell the watts it was delivering.
From 60 Hz at 76 db to 2 kHz SPL is fluctuating by 5 db which is acceptable from my point of view.
Looking from 2 kHz until 20 kHz we see a relatively flat response curve rising minimally from 78 db to 82 db.
Bass down to 60 Hz at 76 db is quite good for a bookshelf speaker.
THD :
Okay, I did not drive the speaker hard to really test for distortions. Nevertheless I can provide a cart showing distortion in % including THD and harmonics from 1st to 5th.
THD stays below 2% from 50 Hz to 150 Hz and below 1% from 150 Hz onward which means the distortion is 40 db quieter than the fundamental. I think that's a good value.
SPL near field with psychoacoustic smoothing:
Near field measurements show us cross over frequency at 1.8 kHz which is far from the 2.9 kHz stated by the company. The reflex port shows a nice drop off until 430 Hz, after that SPL increases again until 880 Hz. I have no idea why.
Impedance and Phase
Impedance has lows at 4.4 Ohms and 4.6 Ohms so according to the 80% rule I would call it a 6 Ohms speaker which lines up with the manufacturers specs.
The two peaks are typical for a ported box:
1st peak at 35 Hz
2nd peak at 88 Hz
The bottom between the first two peaks at 52 Hz is the resonant frequency of the box.
The second peak is higher than the first peak. This means that fb < fs.
fb = resonant frequency of box an
fs = resonant frequency of speaker in air
There seem to be resonances (or enclosure leaks) at 356 Hz and 740 Hz. The first one is more prominent than the second one.
Phase has two lows at -41.6° and -54.3° but luckily impedance is at 11 Ohm and 13 Ohm respectively. So load for the amp should be manageable.
I have been driving the speakers with an old NAD 3020i (20 watts @ 8 Ohm) and it got sufficiently loud (80 decibel) in my living room at low power settings (approx. 30%).
Crossover frequency according to impedance curve is at 1.8-1.9 kHz which is considerably lower than manufacturer data stating 2.9 kHz.
Last but not least some additional charts:
Step response typical for a two way speaker:
Waterfall:
Conclusion:
Since I am new to speaker measurement I am somewhat afraid to give an ultimate opinion. I think the speakers are of decent value for 350 EUR for the pair.
Listening to them for a few weeks I did not get tired of them although there is an increase in SPL in the higher frequencies according to the SPL graph.
What do you think of the measurements and my analysis so far. Any comments or suggestions?
Since this is my first post and my first measurement of a commercial speaker please be patient with me. English is not my mother language so my text might be bumpy to read.
I have built some speakers myself following guidelines from DIY Hifi magazines available in Germany. So far I am not very happy with the results so I started measuring my speakers.
But I am a beginner and I have found this forum and I am so happy to finally be able to move away from pure subjective description to objective measuring.
Again, this is my first analysis of a commercial speaker and I would be glad if you could give me additional advice on things I can improve.
Tempted by many positive online reviews I have bought a pair of Acoustic Energy speakers: AE 100.2 for 350 EUR (before I found this forum).
Let's find out if they are truly any good using the following tools:
- Focusrite Scarlett 2i2 3rd Gen as audio interface
- DIY cables for impedance measurements
- Sonarworks microphone XREF20 with calibration file
- REW 5.20
- Windows 11 Laptop
SPL far field (1m):
I was measuring in my garden. The speaker box was 1.2 meters from the ground and the microphone was 1m from the speaker pointed at the tweeter.
The first graph represents the measurements without any smoothing, the second graph show psychoacoustic smoothing by REW. My neighbors are friendly people and I would like them to stay that way so I was aiming for roughly 80 db. I only have a Hifi amplifier so I cannot tell the watts it was delivering.
From 60 Hz at 76 db to 2 kHz SPL is fluctuating by 5 db which is acceptable from my point of view.
Looking from 2 kHz until 20 kHz we see a relatively flat response curve rising minimally from 78 db to 82 db.
Bass down to 60 Hz at 76 db is quite good for a bookshelf speaker.
THD :
Okay, I did not drive the speaker hard to really test for distortions. Nevertheless I can provide a cart showing distortion in % including THD and harmonics from 1st to 5th.
THD stays below 2% from 50 Hz to 150 Hz and below 1% from 150 Hz onward which means the distortion is 40 db quieter than the fundamental. I think that's a good value.
SPL near field with psychoacoustic smoothing:
Near field measurements show us cross over frequency at 1.8 kHz which is far from the 2.9 kHz stated by the company. The reflex port shows a nice drop off until 430 Hz, after that SPL increases again until 880 Hz. I have no idea why.
Impedance and Phase
Impedance has lows at 4.4 Ohms and 4.6 Ohms so according to the 80% rule I would call it a 6 Ohms speaker which lines up with the manufacturers specs.
The two peaks are typical for a ported box:
1st peak at 35 Hz
2nd peak at 88 Hz
The bottom between the first two peaks at 52 Hz is the resonant frequency of the box.
The second peak is higher than the first peak. This means that fb < fs.
fb = resonant frequency of box an
fs = resonant frequency of speaker in air
There seem to be resonances (or enclosure leaks) at 356 Hz and 740 Hz. The first one is more prominent than the second one.
Phase has two lows at -41.6° and -54.3° but luckily impedance is at 11 Ohm and 13 Ohm respectively. So load for the amp should be manageable.
I have been driving the speakers with an old NAD 3020i (20 watts @ 8 Ohm) and it got sufficiently loud (80 decibel) in my living room at low power settings (approx. 30%).
Crossover frequency according to impedance curve is at 1.8-1.9 kHz which is considerably lower than manufacturer data stating 2.9 kHz.
Last but not least some additional charts:
Step response typical for a two way speaker:
Waterfall:
Conclusion:
Since I am new to speaker measurement I am somewhat afraid to give an ultimate opinion. I think the speakers are of decent value for 350 EUR for the pair.
Listening to them for a few weeks I did not get tired of them although there is an increase in SPL in the higher frequencies according to the SPL graph.
What do you think of the measurements and my analysis so far. Any comments or suggestions?
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