Trunk 4th order build

[///M5 2,833]

Not high at all.

Maybe you should start a thread someone educating people on the benefits of modeling. But you insist on mucking up MY build thread. Well ill inform you your living in the wayback machine then in pre 03. I can tell you right now any world champ in the recent isnt modeling but testing.And im familiar with the winners in nearly every class. Its great thats how you do things and your buds do the same, its awsome. But i seriously think your parading you ways in the wrong place. please go start your own thread elsewhere

It is dumbfounding to me that you even think there is a need for explanation. EVERY car is modelled first BEFORE it is built. Perhaps you should go inform all of the OEM manufacturers why they don't need to model. I can tell you the platform manager for the Impala you drive will laugh his ass off at you, if it helps I can introduce you.

Pretty funny that the world champs bluffed you out. If they don't do something as simple as modelling that is rather laughable.

Lol  i think your high as a kite. I never asked for a explanation of anything nor your input or anyone else on modeling. Your taking this out into left field went from my 4th order to GM modeling a impala. As far as anyone bluffing me your foolish to think that. Anyone that knows anything about SPL its testing and building. Especially in the org i run. im done trying to reason. You guys are pretty hard headed. But ill keep you updated on how my non computer modeled build goes

Every thread on any forum can be searched for at anytime. Premise of your response was that modelling is incorrect or not useful. That is absurd. GM models the complete vehicle acoustic and vibration response. The audio portion being a very simple part of that equation. If someone searches for 4th orders and finds a monstrosity of a recommendation it isn't good for the board.

If you believe that those competing and doing well don't understand the model and their choices that is laughable. A 4th order BP box isn't a good choice for a random design, in particular for either extreme as it is very tunable both with port and enclosure size. Would take about 10 seconds in any modelling program to figure that out.

[Aaron Clinton 2,372]

We aren't saying you design an alignment on a computer and go with it without change, we are simply trying to get people off on an abjective start.

 

When I was working with some of the MECA competitors in the early 2000's (about 200 or so complete builds ago) we would objectively start with a modeled design and then test/tweak from there.  We did not arbitrarily start with volumes on a guess, we would still see how the loudspeakers were going to act as a starting point.

 

Case in point, I completed a high efficieny build in 2003 using the first generation RE 8s.  I was limited in power to roughly 150 watts.  I modeled a multi-tune (pluggable ports, 6 in totall) 4th order vented enclosure and had 3 predicted peaks that went with my 3 tunings.  I knew the modeled peak at the highest point was near the vehicle resonance (1978 full size Bronco) of 56Hz.  When I modeled for the intended peak to coincide near vehicle resonance I was able to net over 143db, at the headrest, on the Termlab, using 153 watts of total input power to my 8 RE8s (19 watts per driver).  This was all possible with little tweaking of the actuall alignment due to carefull planning and simulation.  And I was able to hit my peak SPL at 56Hz, as predicted by both alignment peak and vehicle resonance.  But again, I was only able to do this as easily as I did because I was fully aware of the alignment response BEFORE any actual testing...

 

Again, we have no doubt that you can build great SPL systems, we are trying to stress to the readers of this thread that there are more objective ways to start. 

 

Just think of how many unknown alignment variables you can eliminate by modeling first...

 

I have been doing this for well over 20 years and I still learn new things everyday.

 

Ouch, I remember that install, didn't really 11 years had passed.

[95Honda 486]

Yup, and I think the 152+db Tempest Durango wall was built well before that!  We are getting old!

[97maxima 9]

So after some down time i ended up doing a little modding. Moved my front wall forward and built a port plate. In the end gained a little front chamber volume and lower tuning. Going to find the peaks and do a little metering, sealed and meca style. Im pretty happy with the way it sounds now

[SpeakerBoy 64]

Looks awesome

[jcarter1885 995]

Looks way better bow, glad you like the results.

[97maxima 9]

Looks awesome

 

 

Looks way better bow, glad you like the results.

Thanks. big increase in port area made them come alive. Had to pretty it up a bit

[jcarter1885 995]

Lately the port plate seems to be the way to get the best results witn 4th orders. Wish i could hear this thing.

[97maxima 9]

Lately the port plate seems to be the way to get the best results witn 4th orders. Wish i could hear this thing.

I would really preferred to not stick the port in the box but run it externally. Ill run it like this for a while, maybe try a slightly smaller port to drop tuning again. and maybe do a ext port down the road. Its a pleasure to listen to for sure. road around last night for a half hour and beat them relentlessly 

[Lee Carter 150]

looks amazing!  nice workmanship!

[antoinez28 62]

Man that look like...WOW in fe build log can't wait till I start being able to build like that and play around with 4th orders

[///M5 2,833]

Man that look like...WOW in fe build log can't wait till I start being able to build like that and play around with 4th orders

You have a Tahoe, a 4th order BP would be a waste of space. Trunk cars can be an exception.  Btw, a ported box is also a 4th order beware how you use the term.

[antoinez28 62]

Man that look like...WOW. nice build log can't wait till I start being able to build like that and play around with 4th orders

You have a Tahoe, a 4th order BP would be a waste of space. Trunk cars can be an exception. Btw, a ported box is also a 4th order beware how you use the term.

1st off it's not for my tahoe...I do have other cars...that's my way of giving props that's all...I know what I'm going to do with my tahoe by the way... Edited November 20, 2014 by antoinez28