Eric Holdaway may have been the first person to figure out that the dash of a car can extend the mouth of a horn.
A lot of these discussion are lost forever, because a lot of the innovations were in the 80s and early 90s, before the World Wide Web even existed. So we're going so far back, it's difficult to pinpoint who came up with the concept of doing this in a car first.
Of course, there were tons of people who put horns in the BACK of vans, even back in the 70s. That was commonplace.
But who figured out that the dash can extend the horn? Again, the answer to that question is debated, but Eric Holdaway might be the guy.
When the New York Times wanted to talk about car audio, they went to Eric Holdaway: The Audiophile’s Goal Is to Rev Up the Music - The New York Times
Eric Holdaway and his team at Speakerworks built the Buick Grand National that Clark competed with in the 90s. The Grand National was purchased by Clark from Speakerworks.
If any of you have enjoyed my nutty waveguide projects, you can thank Eric Holdaway. I cruised into his shop one day after I'd built a couple of car audio waveguides. I wasn't sure if I was doing it right, so I figured I'd go hear The Real Thing. (I'd never heard car audio waveguides in anyone else's car in my life, everything that I'd built was based on things I'd seen in magazines, Car Audio and Electronics in particular.) After demoing Eric's waveguides, I was ready to buy them... when Eric encouraged me to keep experimenting.
I thought that was really neat. That he'd pass on a sale, to encourage a young tinkerer to keep on tinkering.
And 25+ years later, I'm still tinkering
A lot of these discussion are lost forever, because a lot of the innovations were in the 80s and early 90s, before the World Wide Web even existed. So we're going so far back, it's difficult to pinpoint who came up with the concept of doing this in a car first.
Of course, there were tons of people who put horns in the BACK of vans, even back in the 70s. That was commonplace.
But who figured out that the dash can extend the horn? Again, the answer to that question is debated, but Eric Holdaway might be the guy.
When the New York Times wanted to talk about car audio, they went to Eric Holdaway: The Audiophile’s Goal Is to Rev Up the Music - The New York Times
Eric Holdaway and his team at Speakerworks built the Buick Grand National that Clark competed with in the 90s. The Grand National was purchased by Clark from Speakerworks.
If any of you have enjoyed my nutty waveguide projects, you can thank Eric Holdaway. I cruised into his shop one day after I'd built a couple of car audio waveguides. I wasn't sure if I was doing it right, so I figured I'd go hear The Real Thing. (I'd never heard car audio waveguides in anyone else's car in my life, everything that I'd built was based on things I'd seen in magazines, Car Audio and Electronics in particular.) After demoing Eric's waveguides, I was ready to buy them... when Eric encouraged me to keep experimenting.
I thought that was really neat. That he'd pass on a sale, to encourage a young tinkerer to keep on tinkering.
And 25+ years later, I'm still tinkering
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To be fair to the Facebook mods, basically it went down like this:
- I made a statement that "car audio waveguides depend on the dash of the car to extend their mouth." This was in response to someone who was considering using some car audio waveguides at home.
- The mods deleted my comment, stating flatly that "I was incorrect"
- In my experience, Facebook audio groups tend to attract a lot of people who are new to DIY, so my assumption was that one of the mods simply didn't understand that the dash of a car is a fundamental part of a car audio waveguide. Due to this, I posted a survey asking "Does the dash of a car extend the mouth of a car audio waveguide?"
- That's when they brought out the ban hammer. They sent me a message saying that "(I was) taking a large number of beginners down an incorrect path." and that "At best, I would say that the dashboards/a-pillers/etc...are a really rough, uncontrolled baffle and acoustic space. They are a reduction of radiating environment from 4/2pi down to 1/2Pi or less and provide additional early acoustic reflections…but they don’t extend the horn."
The thing that bums me out about this exchange, is that it's part of a larger trend that I've been noticing on Facebook and Youtube:
There are a lot of people spreading ideas that are incorrect on social media.
Transmission lines are the most obvious example. Literally 95% of the YouTube videos about transmission lines are just flat out wrong.
We have great tools to model transmission lines. Hornresp in particular. But Hornresp is challenging to learn, and a lot of people want to tinker with transmission lines. So they go on YouTube, they look up videos about transmission lines, and then they end up building them the wrong way.
I think that this is a fundamentally intractable problem with the Internet. There are guys like Brian Steele, publishing great information at diysubwoofers.org. But for every Brian Steele, there's a hundred people publishing videos on YouTube that are just flat-out wrong.
And if you're new to the hobby, you have no way to determine who the expert is. Even worse, it's easy for a novice to ignore the advice of experts, because experts are often difficult to follow. For instance, I've seen exchanges on the Facebook transmission line page, where four people are disagreeing with things that Steele suggests, and I get the vibe that a lot of novices would probably assume that since four people are saying he's wrong, he must be wrong. But I can't think of a single time I've disagreed with Steele, he knows tlines inside and out. What's happening on Facebook is that there are more novices than experts, and the novices are drowning out the posts by the experts.
Basically it seems like we need to come up with some compromise between how things were done in the 90s, when audio advice was dispensed by experts in the AES, and how things are done nowadays, when audio advice is dispensed by anyone with a keyboard.
Facebook has made some strides in this department. For instance, they "flair" users who provide posts that are generally upvoted.
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Not to be rude John, but you've just noticed that social media (in general) and Facebook (in particular) are largely responsible for the spread of misinformation?
I get it that you're passionate about waveguides - and I've benefitted from learning stuff from many of your posts (no BS, I read almost every waveguide and MEH thing you post) - so this is what you focus on. But social media has messed up a whole lot more than just the sound in someone's car!
I get it that you're passionate about waveguides - and I've benefitted from learning stuff from many of your posts (no BS, I read almost every waveguide and MEH thing you post) - so this is what you focus on. But social media has messed up a whole lot more than just the sound in someone's car!
It's just a general realization that audio discussions on Facebook and Youtube are very different than on places like diyaudio, avsforum, audiosciencereview, diymobileaudio, audioasylum, etc.
Basically the audience is much larger but the quality of the discussions is much different, IMHO.
I have never participated in any of the Facebook audio groups. How strange they would ban an "incorrect post" in a forum group chat. Is it the specific forum "owners/mods' doing the deleting and banning?? Sorry just not clear having never been there.
Talk about an idea killing format. We all go down "wrong" roads that's how you learn to think independently. Through mistakes and mis-steps.
Rob
Talk about an idea killing format. We all go down "wrong" roads that's how you learn to think independently. Through mistakes and mis-steps.
Rob
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Facebook and Youtube play to the largest audience and, as a result, they are the least knowledgeable (just basic probability). Same for every interest group. It used to be that if you didn't know what you were talking about you wouldn't get up on a soapbox and spout (and if you did, you would at least preface things by saying you were not an expert). Nowadays it's OK to be proud of your ignorance....
John, are talking about the DIY Loudspxxker Design Pxd?
I left Facebook over a year ago for different reasons but the mix on that forum was weird. There was one big chief and his kid brother and fan club and then a handful of academically credentialed folks who made themselves a bit too comfortable for my liking.
Very much a cone & dome crew to the bitter end.
One of the guys there used the group to promote his YouTube channel where he had made a video picking apart a DIYSG coaxial speaker kit. In an effort to shore up his reputation as an “expert”, he went above and beyond badmouthing the measurements and engineering behind the kit. The result was what once was a best-selling (and consistently positively reviewed) speaker at DIYSG stopped selling virtually overnight and Erich had to take a bath on his inventory of it.
I remember another occasion where you were having a contentious exchange with one of the Chosen Few over there and the moderators were clearly in terra incognita so they just sided with the Chosen Few. At one point I stepped in to speak up on your behalf and mention that your arguments were sound and were well received elsewhere (namely, this forum). In their defense, the Big Chief’s brother stepped in to slag this forum and the level of expertise that could be found here. I pushed back encouraging him to delete his post unless he was ready to have a public discussion about why diyaudio members such as Earl Geddes and Tom Danley weren't to be taken seriously. Anyway, he had no idea who either of them are which was enough for him to delete his post. I barely avoided being reprimanded for challenging the big chief’s little brother.
I left Facebook soon after.
I left Facebook over a year ago for different reasons but the mix on that forum was weird. There was one big chief and his kid brother and fan club and then a handful of academically credentialed folks who made themselves a bit too comfortable for my liking.
Very much a cone & dome crew to the bitter end.
One of the guys there used the group to promote his YouTube channel where he had made a video picking apart a DIYSG coaxial speaker kit. In an effort to shore up his reputation as an “expert”, he went above and beyond badmouthing the measurements and engineering behind the kit. The result was what once was a best-selling (and consistently positively reviewed) speaker at DIYSG stopped selling virtually overnight and Erich had to take a bath on his inventory of it.
I remember another occasion where you were having a contentious exchange with one of the Chosen Few over there and the moderators were clearly in terra incognita so they just sided with the Chosen Few. At one point I stepped in to speak up on your behalf and mention that your arguments were sound and were well received elsewhere (namely, this forum). In their defense, the Big Chief’s brother stepped in to slag this forum and the level of expertise that could be found here. I pushed back encouraging him to delete his post unless he was ready to have a public discussion about why diyaudio members such as Earl Geddes and Tom Danley weren't to be taken seriously. Anyway, he had no idea who either of them are which was enough for him to delete his post. I barely avoided being reprimanded for challenging the big chief’s little brother.
I left Facebook soon after.
Hey John. Some free advice from a guy that has made his living designing pro audio loudspeakers for almost 30 years..... take the time you invest in arguing with people on social media about horn/speaker design and go out to your garage and build something instead, maybe take your dog for a walk or watch a movie with your wife. Your life will be much less frustrating. Make your contact info known and the people who are really interested in learning and that have an open mind WILL FIND YOU. Social media has become a toxic environment where people are more interested in arguing and insulting each other. If you think the dash board extends a horns length and have data to prove it then share it with people who are interested in learning. Make yourself accessible to those that are interested and they will find you.
Cheers,
Todd
Cheers,
Todd
John,
I feel your pain from the ban, but still would like to point out some mistakes, simply to avoid you going through more pain.
1) In post #135, you use a photo of a diffraction horn mounted under a dash. The dash in that case is technically a baffle, not a horn mouth. The horn's basic frequency response would not be materially changed by the baffle.
2)Oh well, sounds harsh.
3) A dashboard may or may not be a fundamental part of a "waveguide".
In the case of the horn depicted in #135, it is not.
In the case of the horns depicted in #140, the dashboard and windshield comprise the horn walls, the mouth of which extends from the bottom of the dash to the top of the window. The gap between the dashboard and windshield is a diffraction slot near the horn throat. You incorrectly called that gap "the mouth of the waveguide".
4)Incorrect use of technical terms will continue regardless of your ban or anyone correcting your mistakes.
5) I agree completely that there are a lot of people spreading ideas that are incorrect on social media.
It was over a decade ago I first attempted to explain the diffraction horn concept to you in one or more of your DIY threads, more recently the difference between between baffle step response and a "waveguide".
Loudspeaker Enclosures are Waveguides
I still try to correct mistakes, even when they are mine
Art
Attachments
Watchng from the cheap seats. Wow, a man whose project's labor time alone is equal or more than what many cheaper new cars cost. Admirable.
Just a comment on Facebook and the other social media. Is the "moderation" (I call it "censorship") so now so heavy handed that you get suspended for so trivial an "infraction", really? Are they "publishers," "public forums," "common carriers," something else? Social media and their pals in government probably like the status quo, which based on your descriptions alone, would seem to provide the "optimum" blend of a "Potemkin Village" public forum with pretend "free speech", yet with the highly desirable ability to gag people on a case-by-case basis. I quit social media years ago and have no intention to return. Will this comment incur the wrath of a mod here? It wouldn't be the first time.
Just a comment on Facebook and the other social media. Is the "moderation" (I call it "censorship") so now so heavy handed that you get suspended for so trivial an "infraction", really? Are they "publishers," "public forums," "common carriers," something else? Social media and their pals in government probably like the status quo, which based on your descriptions alone, would seem to provide the "optimum" blend of a "Potemkin Village" public forum with pretend "free speech", yet with the highly desirable ability to gag people on a case-by-case basis. I quit social media years ago and have no intention to return. Will this comment incur the wrath of a mod here? It wouldn't be the first time.
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There's a few forums that I participate in specifically because they have a lot of novices. For me, it's just a way to Pay it Forward.
For instance, if Eric Holdaway had sold me a set of waveguides two decades ago, I probably wouldn't have gone and started designing my own. The fact that he encouraged me to DIY it was pivotal, because barely anyone was doing it at the time. (Not speaking of horns in general, but speaking very specifically about waveguides in cars.)
For most things in audio, I don't have strong opinions. For instance, I couldn't care less about amplifier arguments. It's just not my field of expertise.
But any time I see someone who's thinking about putting waveguides in a car, I'm going to give them a push, because realistically there's probably less than a hundred people in the world who are promoting that subject.
Patent expired?
Hi,
I was reading through the thread and also looked for the original patent to learn more details. I saw that the patent expired "fee-related" in 2018.
I'm not an expert on patents, but it reads to me that the solution is no longer covered by the patent.
US7708112B2 - Waveguide phase plug
- Google Patents
What do you think about it?
Best regards
KH
Hi,
I was reading through the thread and also looked for the original patent to learn more details. I saw that the patent expired "fee-related" in 2018.
I'm not an expert on patents, but it reads to me that the solution is no longer covered by the patent.
US7708112B2 - Waveguide phase plug
- Google Patents
What do you think about it?
Best regards
KH