So which one? The long TL type or the short manifold design?

 

Before we worry about the wave guide, I think that you should think more on the poor placement of the back alignment of subs... Do you have to stay with 15"s?

 

sorry i am not sure what your asking me... what are you referring to...

 

and you really, truelly believe this?

5 years ago 148 db's on the audio control meter would equal to about 141 db's on today's measuring device.

140 db's these days with what u listed is pretty much the standard.........attainable with a ported box. matter of fact my girl's car produced a slightly better result with a half shacked slot ported box back in 2006.

why do you not believe me? just bacause I dont know as much theory as you do and can't put it in fancy terms you discredit my claim?

why do you think in a car a ported box would not produce the same result as any tapped horn or bandpass?

 

Did this help improve my credibility in your mind

Not really. Unfortunately you are coming off like a 3rd year Engineering student - full of theory but short on application. Touting your own technical superiority, arguing completely irrelevant physical properties of cables, suggesting that a horn enclosure is a good solution for SPL in a car, resorting to name calling when opposed, and stating that you were at MD does not help.

I know it's hard for a consultant but if you want a shred of acceptance and credibility, you should attempt to actually try to help people out rather than talk down to them and continually tell them that there is no way they could understand what is going on anyway. You have asked people to ask you questions and so far I have seen exactly one real answer.

There may not be any other AEs on here but more than a handful of us have Engineering and/or the real world experience to know more than just a little about what they are talking about.

Yeah I'm probably coming off like a dick but that's my job here..

 

PM - do you know who I am?

 

in all honesty tho, fighting words aside, i would love for you to come out to one of our testing sessions and give us some useful advice. hopefuly something else than what every other MD student, graduate or teacher has suggested thus far. I am not being sarcastic either.

 

Hi Paul

Points taken - a little salty, but tasty enough...

Here where my 'tone' is coming from - I have 18 years of engineer under my belt and even more as an installer. I was around when SPL comps first started and made a lot of money from them... 1987-2001...

I have also taught thousands of people and it has become well evidenced when I have lectured 12-volt students that they are always looking for short cuts and easy answers to complex problems and when you offer up a watered down version, they accuse you of talking down to them - when I or others in a similar position are simply trying to bridge the knowledge gap in an efficient way - not perfect, but workable way. As a result, some listen up, study hard and learn and others defend their existing positions/understanding etc...

I did not invent nor discover the arguments / facts that I have presented - others have with PHD's and universities behind them or large companies etc - but I have learnt them all. And within any technical communities there are always a few schools of thought and resulting debate - but not a t this level, as these are basic things...

The fact that you feel that you're in a position to put me in my place is untoward. As I have read through many of your past posts, it has become clear that, I have more experience and education in audio then you do... I also have all the white papers and test equipment to validate my points...

If you don't like what I am saying then leave my thread - those that come and remain will learn what I have learnt over the past 25-years... I don’t mind a struggle or some debate, but I am not going share what I have learnt from others before me – with those who aren’t here to ultimately make a valid effort to seek scientific fact over subjective opinion...

I am not interested in as much debate, as I am in teaching those that want to learn some mathematical truths...

Am I talking down - yes, otherwise this would be a math lesson and I am sure that no one wants that nor could handled that - if that was the case they wouldn't even be on this site...

And yes you sound like a dick - but so do I... I am sure that neither of us actually are...

Thanks for taking the time to read all the posts... and for your comments...

At first we storm – then we normalize – then we learn with each other! At this juncture we are storming...

In short:

I have performed 1000’s of 12-volt related installations
Designed and installed 1000’s of 12 -120 Volt Audio Systems
I have designed dozens of audio amplifiers & speakers
I have professional tested and reported on 1000’s of electronic devices
I have lectured 1000’s of people all over North America on the very things that we are talking about
I have sat on the board of directors for MECP & CEDIA
I directed the education for the world’s largest private consumer electronic college
I have hosted TV shows...
So all and all – that makes me a well credentialed professional –

So my question to you is = who the %$#@ are you?

 

Perfect I was looking to do something just like that - and perhaps we can work togethere to build one the Danley types of Tapped horns - could be a ton of fun and some good smack talk along the way...

Nice chatting with you!

 

Wouldn't a bandpass tuned to produce only one frequency schnitzle on a ported and tapped horn?

The two of you are going on about in-car vs outdoor like they're related. A tapped horn is a low tuned, highly efficient box that's uncomparable to SPL.

Apparently real-world SPL results don't matter, and Danley has it all figured out. Maybe Yuli with his bunch of subs didn't do something right on the design. If a tapped horn is meant for a large room, why think about its use in a vehicle? I would use one in a mini bus lol. Two different environments, you can't just shimmy over the same acoustical properties, however the efficiency is what, 12 or 24 dB over ported?

Just what is a tapped horn supposed to do from _ to _ HZ?

To me, in the end, that box looks like a tiny ported box with a really long port, inside of a car, and the outside of the car is the listening area lol. A ported box in a car is like a wack 6th order bandpass?, it's a ported box firing into a some-what sealed one without a port length (maybe the windows as ports with zero lengths?).

No 45's in the corners, why? Do you calculate for smoother corners? Is that a combination of theorhetical & actual results?

In a walled off trunk, if a ported box has everything firing forewards, why is it better for the box to stretch to the back of the trunk? Is this because the wave goes to the back of the car and then to the front, producing a longer wave-length, and lower frequency? Is the baffle supposed to minimize all rear-ward waves or is it better to let the waves from the inside of the entire box pass through it easily? Like if you were to seal off the sides, it would be a sealed trunk, but would you want to fiberglass the entire baffle too?

How do you eliminate standing waves? Is ported & sealed different? In a sealed box, is it better for the longer dimensions to have a 45's in the corners, maybe all of them? What's the best shape to eliminate standing waves - an egg, circle, hexagon, maybe all dimensions with 45's (like the outside of a box is square, with the inside corners looking rectangular-hexagonal)?