• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). Come here to have fun, be ready to be teased and not take online life too seriously. We now measure and review equipment for free! Click here for details.

Audioengine A5+ Powered Speaker Review

Robbo99999

Major Contributor
Forum Donor
Joined
Jan 23, 2020
Messages
1,090
Likes
730
Location
UK
No new thread needed. It has been covered on ASR many times.


Use a common mains circuit to power the equipment, if necessary from one power outlet on that circuit.. Dwelling Earth may need to be up to spec.

Follow:

https://web.archive.org/web/20180720124823/http://www.rane.com/library.html#gpm1_1 Wiring, interconnection and grounding.

https://web.archive.org/web/20180720124823/http://www.rane.com/library.html#gpm1_1 Those on level controls.

https://web.archive.org/web/20180722055456/http://www.rane.com/note149.html

Good connectors and properly shielded cables are preferred(they don't cost much).

Inherently noisy gear probably can't be silenced.

Being able to understand and implement the above is required.

I had already made it clear that I may have been lucky with getting low hiss LSR 305Mk11s. But then others may not have set theirs up optimally. Who knows?

My old house has old but safe wiring. No UPS or mains conditioners. I have 16 mains items plugged in for my audio system. No hum and no hiss.

So stop the moaning and work it out, one way or another, now you know how.
Even though I'm sure some of that is good advice (and I power everything off one outlet too), the speaker hiss of the 3 series line is not related to interference, the hiss doesn't get louder with increased amplification volume of the volume knob on back of speaker...it's the same intensity whether at 1 or at dial 10. I initially had ground loop problems that created a hum in my 308's at louder amplifications but that hum was coming from the woofer (not the tweeter), and I fixed that problem anyway by powering everything off one outlet. Yeah, so the hiss is in all 3 series speakers (from tweeter) unless they've somehow released an update in newer models being sold now. I don't think it's fixable by the steps you're outlining.
 

richard12511

Major Contributor
Forum Donor
Joined
Jan 23, 2020
Messages
1,546
Likes
1,995
Off topic but yes these speakers hiss, yes it's audible like someone else mentioned at about 1 meter maybe a bit beyond.

Iv the 308 MK2 .

We all have different abilities to hear things so maybe to some it's not as bad but it's there .
I think we can all hear the white noise sound equally(given how low in frequency it is). I think more likely is that we have different noise floors in our room, different listening distances, and different tolerances for the sound. It's definitely audible a bit beyond 1m. I can hear it if I turn off my fan and AC, and I'm at around 2m. That is assuming that all the units hiss at the same volume. I've got 4 units here that all sound about the same.
 

richard12511

Major Contributor
Forum Donor
Joined
Jan 23, 2020
Messages
1,546
Likes
1,995
Even though I'm sure some of that is good advice (and I power everything off one outlet too), the speaker hiss of the 3 series line is not related to interference, the hiss doesn't get louder with increased amplification volume of the volume knob on back of speaker...it's the same intensity whether at 1 or at dial 10. I initially had ground loop problems that created a hum in my 308's at louder amplifications but that hum was coming from the woofer (not the tweeter), and I fixed that problem anyway by powering everything off one outlet. Yeah, so the hiss is in all 3 series speakers (from tweeter) unless they've somehow released an update in newer models being sold now. I don't think it's fixable by the steps you're outlining.
Mine are brand new(a month old or so) and I can hear it in mine.

I initially said I heard no hiss, but that's because I misunderstood what Rooksie meant by "hiss". The way he described it initially made it seem like a huge deal, so I thought he might be hearing a ground loop or something, but now I think I'm on the same page as y'all.
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
29,278
Likes
81,782
Location
Seattle Area
Thread Starter #124
Let me put it this way - if we would be so sensitive to change in THD from 1% to 0.8% (or 0.7%, all the same) than distortion would deserve more than 3 pages in the Toole's book. But it doesn't, and for a good reason, because it has been proved to be a non-issue as listening tests proved we are not sensitive to it.
It has done no such thing. Distortion is no match for frequency response differences in speakers. This makes sense as everyone, trained or otherwise, can hear frequency response errors. So in tests where both distortion and frequency response changes exist, the latter is much more correlated with preference when testing multiple speakers against each other.

That is not the scenario here. I am testing a single speaker against itself. In the entire frequency range nothing is changed other than the one filter setting where I am aiming to reduce distortion. As such, distortion can and in my opinion, does rise to the top of the heap as the main factor.

Importantly, training absolutely matters for distortion as I have proven time and time again with my ability to detect it at far lower levels than typical audiophiles as shown in controlled, double blind ABX tests. Harman testing shows that their trained listeners had similar preference to untrained listeners. This indicates that their trained listeners are highly skilled in detecting and explaining frequency response errors but not distortion.

Bottom line, your notion that Harman research applies to this topic is misplaced. I have made the same point to Dr. Toole, indeed the first time we met. Audibility and detectability is my area of professional expertise. Take caution in dismissing it based on research in other areas of audibility. No way we can dismiss distortion in the most critical area of our hearing out of hand as you are doing.
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
29,278
Likes
81,782
Location
Seattle Area
Thread Starter #125
Once more, my opinion is that once you applied that filter with -2dB gain you were under expectation bias as you saw distortion measurement. If you didn't you certainly wouldn't be able to detect reduced distortion as our ears simply don't have such fine sensitivity.
The provable level of audible transparency in mid-frequencies is -115 dB. This is 0.0001778. Anything less and you are in gray area, requiring psychoacoustics analysis. I suggest reading more research on audibility of distortions such as this: https://www.audiosciencereview.com/...ity-and-reliability-of-abx-blind-testing.186/

1591470140570.png


1591470174094.png


And from Clark's paper quoted above:

1591470223295.png


Bottom line is that you have no data to base your doubts on. No way any researcher with straight face will say or accept that distortion in 2 to 3% is not audible.
 

Wes

Major Contributor
Joined
Dec 5, 2019
Messages
1,735
Likes
1,447
I agree with Z, you can get 8 inch M Audio at this price and they are waaay more fun.
Really? I have exactly that (Monitor Audio BX8).

Did you do a simple listening comparison? Or double blind tests? Or...?
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
29,278
Likes
81,782
Location
Seattle Area
Thread Starter #127
You were not able detect a wide dip you created with that filter at 4380Hz, which is far easier than to detect a small chnage in the distorion. The reason why you didn't detect it is also related to expectation bias - you thought you were doing the right thing so you were expecting a better sound but in fact you created a wide dip which you didn't notice. In a blind test I actually think you would have a pretty good chance to notice it, but doing it like this you missed it.
Due to my training, I am highly focused on listening for small impairments/non-linearities. It is possible that the dip also had an audible effect but my perception of difference was a sharp reduction in distortion. The effect of tonality change may have also been there but certainly not significant in what I heard.
 

QMuse

Major Contributor
Joined
Feb 20, 2020
Messages
3,124
Likes
2,542
It has done no such thing. Distortion is no match for frequency response differences in speakers. This makes sense as everyone, trained or otherwise, can hear frequency response errors. So in tests where both distortion and frequency response changes exist, the latter is much more correlated with preference when testing multiple speakers against each other.

That is not the scenario here. I am testing a single speaker against itself. In the entire frequency range nothing is changed other than the one filter setting where I am aiming to reduce distortion. As such, distortion can and in my opinion, does rise to the top of the heap as the main factor.

Importantly, training absolutely matters for distortion as I have proven time and time again with my ability to detect it at far lower levels than typical audiophiles as shown in controlled, double blind ABX tests. Harman testing shows that their trained listeners had similar preference to untrained listeners. This indicates that their trained listeners are highly skilled in detecting and explaining frequency response errors but not distortion.

Bottom line, your notion that Harman research applies to this topic is misplaced. I have made the same point to Dr. Toole, indeed the first time we met. Audibility and detectability is my area of professional expertise. Take caution in dismissing it based on research in other areas of audibility. No way we can dismiss distortion in the most critical area of our hearing out of hand as you are doing.
Instead of so much typing I suggest once again you try to measure the difference in the distortion with and without your filter. Maybe that will give you the idea how impossible it is that you noticed it.

Btw, I'm also noticing you are systematically avoiding to answer why you didn't notice the dip you created with your 4438Hz filter.

And finally, you didn't answer my question: what magic potion are you drinking so you have become immune to the expectation bias?
 

QMuse

Major Contributor
Joined
Feb 20, 2020
Messages
3,124
Likes
2,542
Due to my training, I am highly focused on listening for small impairments/non-linearities. It is possible that the dip also had an audible effect but my perception of difference was a sharp reduction in distortion. The effect of tonality change may have also been there but certainly not significant in what I heard.
Wide dip such as that one is much more easilly noticed than small drop in distortion.
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
29,278
Likes
81,782
Location
Seattle Area
Thread Starter #130
My point here is that you can't fight expectation bias. But you know that and you said it yourself several times before, so what has changed that now you're claiming you're immune to it?
Everything is a matter of probabilities. When someone says two DACs sound very different from each other but no measurement points that way, then we can have huge doubt. But when objective measurements show very high levels of distortion and an EQ is used to change the response, the main objection to audibility goes away. Surely we have changed things so audibility change is a given. And backed by objective data. Combined with my training in this domain, then level of doubt by definition needs to go way, way lower.

Your absolute position that my testing must be faulty is not defensible then. You have provided no research, no controlled testing of your own, no psychoacoustics analysis to demonstrate impossibility.

Can I be in error? Sure. This is why I say that I am starting to think that the role of distortion in speakers has been understudied or mostly ignored. I am collecting data on each speaker I test that has high distortion aiming to build more confidence before declaring it such. This is why this information is in the less formal, subjective listening section of the speaker test. Your notion of pouring cold water on it is non-sequitur per above. Just because you have doubt or just want to argue doesn't add anything to the conversation.
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
29,278
Likes
81,782
Location
Seattle Area
Thread Starter #131
Instead of so much typing I suggest once again you try to measure the difference in the distortion with and without your filter. Maybe that will give you the idea how impossible it is that you noticed it.
Once again you are saying I have to do work to address your doubts. You have presented no research, data, or opinion of value on this topic. If I jumped the moment anyone said jump on a forum, I would never land on the ground!

Why don't you go and prove that distortion doesn't change with EQ? Don't know how to measure?
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
29,278
Likes
81,782
Location
Seattle Area
Thread Starter #132
Wide dip such as that one is much more easilly noticed than small drop in distortion.
So you think the two can't be audible together? That tonality changes but also distortion?
 

QMuse

Major Contributor
Joined
Feb 20, 2020
Messages
3,124
Likes
2,542
Your absolute position that my testing must be faulty is not defensible then. You have provided no research, no controlled testing of your own, no psychoacoustics analysis to demonstrate impossibility.
Remember, what has bee seen cannot be unseen. Once you see that THD distorion graph it will impact your listening test. Once you make the filter that is loweering the response at the frequency of the distorion peak you are expceting it to be audible. But it is not. Just try to measure the difference in distortion with and without your filter and it will demonstrate the impossibility.


Can I be in error? Sure. This is why I say that I am starting to think that the role of distortion in speakers has been understudied or mostly ignored. I am collecting data on each speaker I test that has high distortion aiming to build more confidence before declaring it such. This is why this information is in the less formal, subjective listening section of the speaker test. Your notion of pouring cold water on it is non-sequitur per above. Just because you have doubt or just want to argue doesn't add anything to the conversation.
This is where we agree - I also think there might be more to the distortion that describes difference between SQ with speakers. But you know by yourself something like that cannot be proven with sighted listening.
 

QMuse

Major Contributor
Joined
Feb 20, 2020
Messages
3,124
Likes
2,542
So you think the two can't be audible together? That tonality changes but also distortion?
I think you would notice tonality change, but you didn't as you didn't expect it to be there. I think you have the impression that distortion has changed only because you were expecting it to change because of your filter.

Nobody can avoid expectation bias. Remember that story you wrote in some thread about changing parameters of that filter you and your team were developing at Microsoft? Whatever small change in parameters you made you thought it was audible. Untill you took a blind test and than it was not. Same thing here.

That is the reason why I think you would do better without seeing the measurements before listening.

I also think you should design a better, more precise, room EQ filter and use it consistenly in your listening test, without skipping it like you did in test of Vanatoo speaker.
 
Last edited:

QMuse

Major Contributor
Joined
Feb 20, 2020
Messages
3,124
Likes
2,542
Round and round we go , if only we could harness this sort of thing for electricity like a hamster on a wheel .
It may seem we are quarreling but I am in fact trying to give my honest suggestions how I see ways to improve listening tests. I believe thay are of great use but the way they are done now are not putting Amir's listening skills to good use IMHO.

I believe the following needs to be done to improve them:

1) listening test should be done before measurments to avoid expectation bias

2.) better room EQ filter should be designed and consistently applied in each test

3.) speaker correction EQ filters based on measurements should be designed more carefully and listening test should be repeated with them

IMHO it is also worth considering generating a preference score after speaker EQ in the same manner as is preference rating with sub to emphasize the fact that some speakers can be made to sound significantly better with DSP. I think such information presents value to the readers.
 
Last edited:

ReaderZ

Senior Member
Joined
Apr 14, 2020
Messages
413
Likes
274
Really? I have exactly that (Monitor Audio BX8).

Did you do a simple listening comparison? Or double blind tests? Or...?
Simple listening, and double blind is pointlessly unneeded, as bass extension would be a dead give away.

Which BX8 you have? There been like 5 or 6 iterations.
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
29,278
Likes
81,782
Location
Seattle Area
Thread Starter #140
Round and round we go , if only we could harness this sort of thing for electricity like a hamster on a wheel .
This... is the reason I am looking for a new moderator. Applications via PM. Main qualification is to be able to kiss you know what part of me. And in general being opposite of @Thomas savage. Less drinking. Less into kinky stuff. Etc.
 
Top Bottom