Official MWAF 2017 Thread - RESULTS ARE POSTED

[tomzarbo]

I'm the guy with the big cardboard horn.

I'll let others talk about how it sounded, but I'll mention that they couldn't handle the volume level. My theory is that the acoustic suspension protecting the drivers from over-displacement didn't work right, either because the rear chambers were too big or some of them weren't tightly sealed, so some of the drivers were bottoming out, which made for some very funny noises in the loud passages. It's good for the contest to hear now and then what an utter fail sounds like.

Thanks, Matt, for posting all these pictures. And for the view of my, uh, pockets.

One effect of the larger room was that the sound pressure for those of us in the audience was much lower this year than it has been in the past, because we were sitting further away, even if the judges were hearing the same level as they heard in the past.

Meredith

I enjoyed hearing that big cardboard horn, and your explanation on how it worked even more. Those were really small speakers driving it, and not super-duper excursion monsters (for their size) like the ND90's or something like that, these were modest drivers of decent quality and they did pretty well.

Like you said, the issue was the level... it was pretty loud compared to previous MWAF's. Not a knock at all on the event... but there was just a lot more room to fill with sound, so things had to be a bit louder. While my speakers were playing I peeked at Brian's laptop and saw a steady 92 db at the mic in front of the judges table, which was probably a good 10-12 ft at least from the speaker plane. That really taxed this particular speaker as the unlimited category had a few bass-heavy tracks in it... or at least the one where these drivers started to crackle a bit.

But I was kind of astounded by the amount and depth of bass that this was able to generate, I had to chuckle to myself when the bass line kicked in. I guess that's what a horn can do if it's big enough... I wasn't expecting THAT, though! The low stuff was there, it was just a bit too loud to keep it's composure. After you explained to me why you thought it started complaining during the heavier bass passages, it made sense what we were hearing. It doesn't matter though, you still pulled it off as a proof of concept, which I think was more the point. If you had rented a big rig and brought two of these things in plywood, it would have been amazing!

I saw you taking a few measurements at the end of the competition.... wonder what we'll see next year!?!

TomZ

[TN Allen]

"I'm the guy with the big cardboard horn."

Would you please provide more information on the horn? The concept is interesting.
Thank you!

[JavadS]

Maybe next time enlist the assistance of someone, a volunteer, to be the "Official" photographer for the event, thereby freeing you up to take care of all the other things you needed to do.

There were several official photographers at the event from parts express and some privateers as well, but that's a lot different than posting edited images hours after the event over. Matt thanks for snapping those pics that you did, I'll post some pics I snapped as well once I get home and I'm done traveling. =)

[mattp]

Maybe next time enlist the assistance of someone, a volunteer, to be the "Official" photographer for the event, thereby freeing you up to take care of all the other things you needed to do.

Alan,

The photos were entirely voluntary on my part, our photographer was here the whole time. The lack of notes is simply this being my first time and being slightly unprepared to be perfectly honest.

Edit: Thanks Javad.

[Paul K.]

Regarding Meredith's horn speaker system and its performance, I assume everyone noticed that there was absolutely no bass output in the noise tracks that PE used to set the SPL? Without any bass in the noise, the SPL was based on mids and highs being set to an "appropriate" level for judging. If any of the music tracks then had any rather high level bass content, like the first track for the Unlimited category, it would seem possible that the overall level might have been set a bit too high, all things considered. It's very difficult to come up with a single SPL setting that's appropriate for all of the music used IMO. I'm just conjecturing here and may be completely off base.
Paul

[DanP]

Did I miss the winner rundown? What were the results of the competition?

Dan

[mattp]

I enjoyed hearing that big cardboard horn, and your explanation on how it worked even more. Those were really small speakers driving it, and not super-duper excursion monsters (for their size) like the ND90's or something like that, these were modest drivers of decent quality and they did pretty well.

Like you said, the issue was the level... it was pretty loud compared to previous MWAF's. Not a knock at all on the event... but there was just a lot more room to fill with sound, so things had to be a bit louder. While my speakers were playing I peeked at Brian's laptop and saw a steady 92 db at the mic in front of the judges table, which was probably a good 10-12 ft at least from the speaker plane. That really taxed this particular speaker as the unlimited category had a few bass-heavy tracks in it... or at least the one where these drivers started to crackle a bit.

But I was kind of astounded by the amount and depth of bass that this was able to generate, I had to chuckle to myself when the bass line kicked in. I guess that's what a horn can do if it's big enough... I wasn't expecting THAT, though! The low stuff was there, it was just a bit too loud to keep it's composure. After you explained to me why you thought it started complaining during the heavier bass passages, it made sense what we were hearing. It doesn't matter though, you still pulled it off as a proof of concept, which I think was more the point. If you had rented a big rig and brought two of these things in plywood, it would have been amazing!

I saw you taking a few measurements at the end of the competition.... wonder what we'll see next year!?!

TomZ

Tom,

I share your sentiments regarding the bass from this horn. Sitting right in front of it really showed some chest impacting bass response which I was not expecting. I think if he had an array of the full rangers on each side to bump the sensitivity up it would have performed admirably (and at a lower output level). Those little Tang Bands just couldn't keep up with the 16 Auras.

I also noticed while listening to your entry how similarly voiced they are to two Esoteric projects I'm working on. Even the other smaller Esoteric kit that was played sounded very similar as well. This was a surprise to me, I expected to hear a fairly distinct difference between the four projects but they all sounded very similar.

Regarding Meredith's horn speaker system and its performance, I assume everyone noticed that there was absolutely no bass output in the noise tracks that PE used to set the SPL? Without any bass in the noise, the SPL was based on mids and highs being set to an "appropriate" level for judging. If any of the music tracks then had any rather high level bass content, like the first track for the Unlimited category, it would seem possible that the overall level might have been set a bit too high, all things considered. It's very difficult to come up with a single SPL setting that's appropriate for all of the music used IMO. I'm just conjecturing here and may be completely off base.
Paul

Paul,

We used a suggestion from Tom Danley regarding the test tone which was 1k-4k pink noise. This did play a roll with the different projects used and might be something we experiment with next year. We will also think about toying with the idea of a playback level based on project size which can be tricky. This might include two size categories per class. Most of the unlimited class had troubles with the output levels we used.

The levels were initially dialed in using a pair of bookshelf speakers I threw together which were fairly low sensitivity but handled the volume just fine. We thought this would be better than using the CBT24's.

[jhollander]

We used a suggestion from Tom Danley regarding the test tone which was 1k-4k pink noise. This did play a roll with the different projects used and might be something we experiment with next year. We will also think about toying with the idea of a playback level based on project size which can be tricky. This might include two size categories per class. Most of the unlimited class had troubles with the output levels we used.

The levels were initially dialed in using a pair of bookshelf speakers I threw together which were fairly low sensitivity but handled the volume just fine. We thought this would be better than using the CBT24's.

Matt here are a few opinions and suggestions but overall I liked the music and willingness to adjust on the fly (thank you to Tom P. for suggesting the under $200 get turned up)...

Seems like full range pink noise "A" weighted in Omni mic would be a better measurement.
The music track ranged 10 dB higher than the narrow band pink noise so there should be some Spl matching between the music and pink noise.
SPL limiting "open unlimited" is counter intuitive. Uh... these are unlimited speakers right?

[bcodemz]

Another year, another MWAF, another bunch of cool, excellent speakers! It was great to see many familiar faces and meet new people. However, this year just wasn't my year. I feel like I made a fool of myself this year.

For those wondering what happened. I brought my Reference Mini's, an exceedingly ambitious "all out" small speaker. It was supposed to be an impressive speaker given the components, the amount of research, and the crazy amount of work that went in. However, I encountered a number of serious, show stopper road blocks along the way. I *really* like speakers, but I had limited time to work on them as I had a number of more important matters in life to take care of. Even after taking a week off from work in order to make time to fix them, I just barely got it functional the night before MWAF.

However, it sounded extremely muddy and distorted during MWAF. It was because I added 9dB of (mostly) BSC to the speaker for MWAF because at home I have them right against a wall, and I thought I'd add another 3dB to make them sound fuller in a much much larger space vs my smallish living room. Turns out, the MWAF room seemed to really reinforce the <400Hz, so the speaker didn't need the 9dB BSC at all. The 9dB added simply made the speaker sound much more boomy. The +9dB also overloaded the speakers, and the limiter wasn't set due to lack of time, and the speaker distorted from the bass.

I felt so ashamed after that I don't think I even talked to many of you. I didn't care about not placing, I cared a lot more that I lost respect and probably let a number of people down given the potential of this project. However, next year I'll enter again, and it *will* be meticulously tuned and have a number of bells and whistles from fancy DSP magic.

On a brighter note, shout out to MVP Javad for renting out a meeting room at the Hampton Inn for a MWAF after party. A number of us met up there after MWAF to have a way better listen to each other's speakers and chat. That was easily the highlight of this trip. It was a blast listening to a number of fantastic speakers up close with familiar music, of course, turned up LOUD, and having extended chatts with all of you!

[Paul K.]

Brian, don't be too hard on yourself, but I want to make sure I understand. You had 6 dB of BSC programmed in for use in your home, then you added another 3 dB for MWAF, for a total of 9 dB of BSC, right? Since you said your speakers are placed right against the wall at home, I'm wondering why you even need 6 dB of BSC there? If it sounds good to you that way, that's fine and dandy, but it sure seem like too much. In my home my speakers sit with their backs 4 to 9 inches from the wall, depending on the cabinets' depth, and I settled on using only 3 to 3.5 dB of BSC many years ago. That works out quite well in my home and has the advantage of not sounding either too little or too much (to me at least) when I take them to DIY venues. Bass room gremlins at DIY events don't seem to negatively affect them. The way the SPL was set up at MWAF probably had quite a bit to do with your speakers not sounding as good as you would have liked, but 9 dB of BSC was part of it.
Paul

[mattp]

results
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[ernperkins]

Don't worry Brian, the same thing has happened to many of us. A couple of years ago at the SD DIY I worked frantically until the wee hours the night before to get two pairs of speakers ready. Needles to say I ended up with speakers that sounded very blah and that's being polite. Lesson learned. This year rather than work frantically to finish my current build I went sans speakers. It was one of the best times I've had.

[mattp]

Matt here are a few opinions and suggestions but overall I liked the music and willingness to adjust on the fly (thank you to Tom P. for suggesting the under $200 get turned up)...

Seems like full range pink noise "A" weighted in Omni mic would be a better measurement.
The music track ranged 10 dB higher than the narrow band pink noise so there should be some Spl matching between the music and pink noise.
SPL limiting "open unlimited" is counter intuitive. Uh... these are unlimited speakers right?

Thanks for the suggestions.

I agree it sounds counter intuitive. Limiting would not be for open unlimited only. I felt the same way about this class and assumed all of these speakers should have no issues with output capability but most actually did. Just another bug we will have to work on next year. I feel like we made huge strides this year though.

[bcodemz]

Brian, don't be too hard on yourself, but I want to make sure I understand. You had 6 dB of BSC programmed in for use in your home, then you added another 3 dB for MWAF, for a total of 9 dB of BSC, right? Since you said your speakers are placed right against the wall at home, I'm wondering why you even need 6 dB of BSC there? If it sounds good to you that way, that's fine and dandy, but it sure seem like too much. In my home my speakers sit with their backs 4 to 9 inches from the wall, and I settled on using only 3 to 3.5 dB of BSC many years ago. That works out quite well in my home and has the advantage of not sounding either too little or too much (to me at least) when I take them to DIY venues. Bass room gremlins at DIY events don't seem to negatively affect them. The way the SPL was set up at MWAF probably had quite a bit to do with your speakers not sounding as good as you would have liked, but 9 dB of BSC was part of it.
Paul

I had 1dB of BSC when I use the speakers at home because they're right against the wall. There's also an intentional 3dB rise <500Hz to make it a warmer sounding speaker. So I thought going from going against the wall (half space) to free space would need a 6dB BSC. So I added 6dB (forgot about the 1dB BSC already included) to compensate from half space to free space, and another 3dB <500Hz (on top of the original 3dB rise) to compensate for a huge room, for a total of 9dB. So in total I had 7dB of BSC + 6dB of <500Hz rise, which is way too much.

While the MWAF volume was high, if I just left my speaker the way it was back at home, the speaker would have handled the volume just fine with some headroom to spare. But even with the excessive low end rise, it should have been fine on the "Fanfare for the Common Man" song. The bass is centered around 90Hz, and my speakers should have had no problem belting out 90Hz even at that volume as a pair should have been capable of ~110dB at 90Hz at 1 meter. I noticed the speaker distorting earlier than it should again when we were cranking them in the meeting room. I only got about 102dB from ~12 feet away before the speakers lost composure where I expected 105-108dB before noticeable distortion. A good $25 woofer should be capable of staying clean louder than what I've been getting. I will investigate this when I get a chance to push them to the limits at home.

[bcodemz]

Thanks for the suggestions.

I agree it sounds counter intuitive. Limiting would not be for open unlimited only. I felt the same way about this class and assumed all of these speakers should have no issues with output capability but most actually did. Just another bug we will have to work on next year. I feel like we made huge strides this year though.

I agree open unlimited should not be volume limited. I thought the volume was just fine, could be even louder. The under $200's should be volume limited by 5dB or so, but it seems like it already was at this year.

One thing I would suggest is to allow the participants of the open unlimited speakers a chance to make one adjustment to the speaker before the first song ends. This way if a speaker is obviously distorting like Meredith's horns, then the participants could ask for a lower volume so it doesn't make obvious bad noises. My speakers wouldn't have crapped itself either as I knew what I needed to do immediately, and it would have been a quick 20 second adjustment.