Emotiva Airmotiv B1+ Review (Bookshelf Speaker)

[ROOSKIE]

I had to laugh when I saw, 'the product is presently shown as Unavailable on the Emotiva website'. I think Emotiva is respected as a budget hifi direct seller, but their website often has multiple products shown as 'Unavailable'. They also have a habit of introducing new pieces in their product lines and cancelling items after short production cycles. This is probably a consequence of supply and demand but I've never bought an Emotiva product because I was never sure it wouldn't be replaced by something newer and better relatively quickly.

When you are small you reserve production time/tooling time at great expense and often are down the line in terms of who comes first/gets priority.
When you are huge you might actually have your own plant or at least dominate the production time slots.
Emotiva is likely doing the best they can. (Especially with being small scale)
Do must realize they dont want to be out of stock this often?
In any case all the small companies are at the mercy of many demands that can be hard to perfect and slight variations can break the bank.
Think, LG just stopped making cell phones after several years straight of billions per year in losses. Billions. No small company can compete with large companies in terms of ability to ride loss waves.
I actually can't beleive how emotiva, chane, hsu and myrid other small co's pull off what they do.
Mind blown when I contrast with the resources of the big co's like Harman, Sennheiser, Klipsch ect.

 

[Bear123]

I agree on your assumption but disagree that it is not apparent that good engineering went into this design. Internet is full of calculators that gives you the dimensions for a box to place two units and a port. Doing that is not designing. It is the start of a design. It is perfectly possible that the drive units are of good quality for the price, hence it sounds OK for the price. That is also not design, it is procuring!



I hope so. They shouldn't buy this speaker though as it's measurements show a bad port resonance peak!

It's remotely possible that you are right, and the excellent performance of this speaker is random luck.

I'll happily place my bet on my assumption that good design and engineering went into this speaker. We will have to agree to disagree here.

 

[sarumbear]

We will have to agree to disagree here.

Thank you for participating the debate.

 

[Bear123]

Thank you for participating the debate.

Your very welcome. Despite the relatively minor effect of the port resonance on this speakers response, it remains one of the objectively best speakers at or near its price point. In your opinion, a stroke of luck, but a good result nonetheless! The JBL stage A130 seems to have a much more egregious resonance in the same area, although it is larger and wider.

Curious, do you have a recommendation for a more well engineered speaker at this price point? Or even one that isn't well engineered but just gets lucky?

 

[sarumbear]

In your opinion, a stroke of luck...

If you re-read my posts you will see that I didn't use the term luck. I said the choice of good drive units are most likely the reason why the speaker sounds and measures OK (bar the port resonance issue). I was arguing the fact that it is not a well engineered speaker as it has demonstrable faults, which I think can be corrected without a cost penalty. The "luck" you mention can be in the procuring of the drive units.

Luck almost never happens in engineering.

 

[amirm]

I think port resonance has never had the attention that we have put on it. Others do such tests but review speakers so infrequently, and with speakers of so many different designs, that such observation has not popped out. Now that it has, hopefully it will get resolved in the future.

 

[hardisj]

Quite an impressive speaker at the price. But, once again, if companies could make a better port the performance would be darn near incredible (or just don't use a port at all, which I think makes more sense for a small speaker like this).


The mean SPL on-axis is 85.56 dB (300Hz to 3kHz).
Response linearity is -2.44/+2.82 dB (80Hz to 16kHz).

 

[hardisj]

I think port resonance has never had the attention that we have put on it. Others do such tests but review speakers so infrequently, and with speakers of so many different designs, that such observation has not popped out. Now that it has, hopefully it will get resolved in the future.

I think the other contributing factor is the NFS and other anechoic-like measurements are the only ones that show these resonances as clearly and thoroughly. Especially when those resonances occur in the midrange. This is because most reviews are using quasi-anechoic methods and have to resort to a gated response that limits resolution to ~300-500Hz and, at best, maybe 100Hz increments. Certainly not the single digit resolution we see with the NFS.

 

[sarumbear]

(or just don't use a port at all, which I think makes more sense for a small speaker like this.

On the contrary; on a small speaker like this a port is the only option. If you look at the chart below you will see that almost an entire octave below 100 Hz is generated by the port. Without the port the lowest bass guitar tone (60 Hz) will be around 10 dB down. Such a bass shy speaker is not useable as a full range speaker.

 

[hardisj]

On the contrary; on a small speaker like this a port is the only option. If you look at the chart below you will see that almost an entire octave below 100 Hz is generated by the port. Without the port the lowest bass guitar tone (60 Hz) will be around 10 dB down. Such a bass shy speaker is not useable as a full range speaker.

I understand why it is there. My POV hinges on the fact that I know of very few "full range speakers" and I would hope most people will use these with a subwoofer. Once that happens, there is no need for a small bookshelf speaker to play any lower than 100Hz or so (depending on size, subwoofer, room, etc).

I see companies making these choices primarily to get the buyer to think "oh, well, it's ported so it must play low". The educated consumer may be wise to the fact that a subwoofer makes this moot. The astute consumer knows this and also understands the port design in such a low-priced speaker may create its own issues. There's a multitude of "what-if" considerations here. But, again, I come from the perspective that you're going to buy a subwoofer anyway... seal the port up, take out that +3dB octave-wide bump at 1kHz and enjoy a better sounding system (not to mention the strain taken off the woofer and thus the increased dynamic capabilities).

 

[Dennis Murphy]

I will be the first to admit that I know a lot more about the why's and wherefore's of crossover design than the physics of port resonances. I always turn that part of speaker design over to Paul Kittinger, who has spreadsheets that allow him to calculate the best location for the port. That still leaves me a little confused when situations like this occur, and maybe I'll be able to pick up something useful in this discussion. I haven't worked on the "+" version of the B1, but I did modify the first version, which measures very similarly. When I see a peak in the 1 khz - 1.5 kHz region, I usually assume it's the dreaded resonance caused by a less-than-optimal cone-surround interface. The treatment for that is a crossover mod, probably using a trap circuit of some kind. When I traced through the stock woofer crossover circuit of the B1, I discovered that there was already a 3-element trap in play. The problem was that the values chosen for the L,R,and C weren't effective in dealing with the peak. I redid those values, and the peak disappeared. See before and after plots below. It frankly never occurred to me that the underlying problem was a port resonance, and I'm not sure there's much I could have done about that in any event.

So the question is whether this indirect approach was markedly inferior to a ground-up redesign with a relocated and perhaps reshaped port? What I did presumably still leaves the resonance untreated, and I guess I just introduced a dip in the woofer response to compensate. It seems intuitive that we would be better off without the resonance, but the audible improvement was significant and brought the sound of the B1 up to par with other 2-ways with more careful port placement.

 

[sarumbear]

I understand why it is there. My POV hinges on the fact that I know of very few "full range speakers" and I would hope most people will use these with a subwoofer.

It is impossible to correctly cross an off-the-shelf speaker to a subwoofer without an adjustable active cross-over. As the proliferation of affordable external active cross-over is not going to happen anytime soon your solution will always generate a compromise, not to mention more than double the cost of two ported small speakers.

 

[respice finem]

#90: This, and, provided buying 2 speakers and a matching subwoofer, why ported at all? No port = no port-related issues.

OT: The port "worries" affected my decision to buy the non-ported Neumanns and keep in mind the option to buy their also non-ported sub or two, all active, and adding the sub(s) would also add DSP. No comparison in price, nor technology, I know. But considering the Neumanns are not a new design (actually this is from Klein & Hummel 18? years ago), I would expect today this "line of thinking" to be more prevalent than it is.

SOT: in the 80s I had a Canton set Plus C / Plus S, large sub, small "satellites". For these times, those were good speakers IMHO. All passive and not ported, and built to match each other. So it's possible passively too, if the manufacturer wants to. BTW I gave them away to an older relative and they're still working.

 

[AverageJoeAudiophile]

I will be the first to admit that I know a lot more about the why's and wherefore's of crossover design than the physics of port resonances. I always turn that part of speaker design over to Paul Kittinger, who has spreadsheets that allow him to calculate the best location for the port. That still leaves me a little confused when situations like this occur, and maybe I'll be able to pick up something useful in this discussion. I haven't worked on the "+" version of the B1, but I did modify the first version, which measures very similarly. When I see a peak in the 1 khz - 1.5 kHz region, I usually assume it's the dreaded resonance caused by a less-than-optimal cone-surround interface. The treatment for that is a crossover mod, probably using a trap circuit of some kind. When I traced through the stock woofer crossover circuit of the B1, I discovered that there was already a 3-element trap in play. The problem was that the values chosen for the L,R,and C weren't effective in dealing with the peak. I redid those values, and the peak disappeared. See before and after plots below. It frankly never occurred to me that the underlying problem was a port resonance, and I'm not sure there's much I could have done about that in any event.

So the questions is whether this indirect approach was markedly inferior to a ground-up redesign with a relocated and perhaps reshaped port? What I did presumably still leaves the resonance untreated, and I guess I just introduced a dip in the woofer response to compensate. It seems intuitive that we would be better off without the resonance, but the audible improvement was significant and brought the sound of the B1 up to par with other 2-ways with more careful port placement. View attachment 123450View attachment 123452

Hi Dennis would you be up for sharing those changes you made?

 

[hardisj]

It is impossible to correctly cross an off-the-shelf speaker to a subwoofer without an adjustable active cross-over. As the proliferation of affordable external active cross-over is not going to happen anytime soon your solution will always generate a compromise, not to mention more than double the cost of two ported small speakers.

I feel like you're putting users in to a box where none will have such tools at their leisure.

Your solution (a full range speaker) will have compromises as well. Price and space to name two. There are no free lunches.

So, I go back to... if someone said "hey, Erin, would you recommend (insert low cost small 2-way bookshelf speaker here) for full-range use?" my answer would be "no". At least, none that I can think of thus far come to mind.

If you see these as a full range speaker then obviously I can't convince you of my points. But I can't be convinced this is anywhere close to a full range speaker. So, we'll have to simply disagree.

 

[AverageJoeAudiophile]

It is impossible to correctly cross an off-the-shelf speaker to a subwoofer without an adjustable active cross-over. As the proliferation of affordable external active cross-over is not going to happen anytime soon your solution will always generate a compromise, not to mention more than double the cost of two ported small speakers.

This seems rather short sighted or I'm not following correctly. Any remotely modern AVR will have bass control and allow for appropriate crossover ranges. If it has preamplifier output or you choose a miniDSP your able to use the separates of your choosing.

 

[AverageJoeAudiophile]

When port resonance is mentioned are we talking about the port plastic itself physically resonating (vibrating) and causing additional output at 1000hz, or am I totally misunderstanding?

I too have the same question. If so, why not just dampening the port with weight and move the resonance higher up and at a lower volume.

 

[MZKM]

Really don’t want to derail this thread;

The mean SPL on-axis is 85.56 dB (300Hz to 3kHz).

Again, a 0.09dB difference. However, the Uni-Fi 2.0 you did we get the same 83.3dB.

I know you said it could just be software differences (maybe significant figures), but just to put it out there, what I am doing:

dB-> Pascal: 0.00002*10^(dB SPL/20)

Average (mean) pressure of frequencies within 300Hz & 3000Hz.

Pascal -> dB: 20•log10(Average / 0.00002)

 

[sarumbear]

This seems rather short sighted or I'm not following correctly. Any remotely modern AVR will have bass control and allow for appropriate crossover ranges. If it has preamplifier output or you choose a miniDSP your able to use the separates of your choosing.

I assume you are not following me correctly.

1- We are talking about stereo, a pair of speakers.

2- Very few AVRs have adjustable cross-overs for subwoofers. (I know just one, it costs $15K.) The crossover frequency is just one aspect of the crossover. What about slopes?

You can certainly make-do and have sound. It can be good sound even. That doesn't mean your engineering is correct.

 

[hardisj]

Really don’t want to derail this thread;

Again, a 0.09dB difference. However, the Uni-Fi 2.0 you did we get the same 83.3dB.

I know you said it could just be software differences (maybe significant figures), but just to put it out there, what I am doing:

dB-> Pascal: 0.00002*10^(dB SPL/20)

Average (mean) pressure of frequencies within 300Hz & 3000Hz.

Pascal -> dB: 20•log10(Average / 0.00002)

Same thing I’m using. But, honestly, man, I just don’t care. 0.09dB calculation difference? This is picking nits to the nth-degree. Literally.