This is the discussion thread for the LLT Explained Sticky Thread.
Very interesting read Steve. Well done. I quite enjoyed it.
I do have to take a small exception to your three graphs in the above post, although I suppose you copied them from elsewhere and had no control.
The vertical scaling is quite inconsistent between the three graphs, and makes it difficult to draw meaningful conclusions......
brucek
Yeah, three different owners running their measurements in three different months. Not ideal, but just a very generic representation of what can be achieved at various tuning points with different drivers.I do have to take a small exception to your three graphs in the above post, although I suppose you copied them from elsewhere and had no control.
The vertical scaling is quite inconsistent between the three graphs, and makes it difficult to draw meaningful conclusions......
Well the coupling area with an LLT will begin around 25-30hz and extend down to just below the tune - below that, the 4th order rolloff comes into play and there will be a dropoff. Flat output definitely won't go on for ever. Considering the third sub's tuning is coming in around the high 16hz area I believe, the extension to ~13hz is pretty impressive. If you were to take a ported sub that measured very flat to 18hz anechoically, like an Axiom EP1500, you would not get such results without heavy EQ in room.it would "seem" that the only one that is coupling to the room properly is the first example given in the 18" Avalanche
HOPEFULLY :bigsmile:Hopefully this will save you from answering so many questions
Thanks. A logical and factual explanation of the real benefits was one of my top goals, as there are people with no clue as to how such a design really works saying things about it that are completely wrong and backwards - it's not a knock, but they just don't fully grasp the design intent. For people who have enough interest to want to understand why this design works and why it came about, hopefully this will shed some light.Excellent explanation. Very factual, scientific, and based upon repeatable results if the "formula" is followed
Yeah, I might just list my main designs for popular drivers so it could be a one stop source.A little cheat sheet you could put out as a starting point for people thinking about building one of these might give them an idea of what they are getting into
I don't know Ex? I'll be real surprised if you don't do another sealed.:bigsmile:My next but very distant project will be a ported Avalanche 15" sub. Whether or not it'll fit the LLT description by design is still up in the air. Haven't figured out where an LLT would fit in my room
Reminds me of the Fresh Prince song, Parents Just Don't Understand :R So how many more years of school do you have before you can move out and go nuts?My mom didn't like the idea of housing a water heater in the living room She just doesn't understand the sacrafices we need to make to join the brotherhood!
Yeah, you gotta fight. For your right. To paaaaaaaaaaaaaaaaaar-tay. addle:Reminds me of the Fresh Prince song, Parents Just Don't Understand :R So how many more years of school do you have before you can move out and go nuts?
hahaha, i guess i'll never enjoy that single life eh :joke: Thats the only thing I honestly feel like im missing out on...I've been there, done that. At this point I guess you're right, couldn't see myself without her though...its that nice spending time w/ her. Hope it stays this wayWait a second, so if I understand this right, you haven't finished college, but you're married? :no: You're married but you live at your parents house? :no: Oh man.....oh man :sad2: Before you got the chance to be independent, you went and got married, so now you will transition from one form of control (parents) directly into another (wife), one that's supposed to last for the rest of your life, with no buffer inbetween. But hey man, different strokes for different folks, more power to you.
Hey Ex...I had a dickens of a time securing 22" sono!..I was just about ready to give up when I found out that HD had the muscle to order it for me. Anyway 20" and 24" is easy to find here in the Portland metro area. I guess the 22" is considered a specialty size from what I hear.WillD made it clear that 22" tube might be hard to find) and going a little over 4' is okay.
:help: :mooooh: Oh dear...I got plenty of 22" sono including drivers, but you have that part covered. I guess I could do a kit for you minus the driver if your interested? The right packaging costs $$ though.addle:happen to still have any spare sono's Stevenn?:bigsmile: