Finally porting the Tang Band 6.5's...need help/ideas

[ItalynStylion 10+ year member]

I've had my current setup for a while and I've been REALLY satisfied. Right now I've got 4 Tang Bands in 1 cube sealed (pictured bellow). They sound great but they can't keep up with my Focal 165V1's and porting will help solve that //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

So I've run the numbers through Unibox using the following TS parameters...

Tang Band-W6 1139

Fs 38.00 Hz

Re 3.60 Ohm

Qms 2.65

Qes 0.47

Sd 140.0 cm2

Vas 12.0 l

Xmax peak 13.00 mm

(Le) 1.35 mH*(wth is LE and where do I get this number?)

(Le2) 0.00 mH

(Re2) 0.00 Ohm

Nominal Power 78.0 W

Hoping that all is accurate; let's move on to the fun stuff!

The recommended net volume is 1.7 cubes, but I've found that by increasing the volume to 1.94 I can extend my low end extension. If I tune to 34hz the response is VERY flat. Pic bellow of the FR graph.

What size port tube should I use? I was thinking a 4" precision port would be fine but the chart says to use one 6" minimum //content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif

Will I be cool with a single 4?

Click to read more...

 

[ItalynStylion 10+ year member]

Here is a picture of my trunk before I did the box that is bolted to the IS300's rear deck. I was planning to build a box that sits between the wheels. My initial idea is to face the subs and port straight up and have the amp mounted to the face of the box that is closest to the trunk opening.

(PS: the amp is a sorta large so that is going into the design plans too)

 

[BrianChia 10+ year member]

Le is a measurement of the inductance of the voice coil. It's not really too important for enclosure design.

If you're trying to achieve a flat response curve, keep in mind that the you will be getting an in car boost of typically 6-12db/oct that you should to account for.

This may be helpful:

http://linearteam.proboards12.com/index.cgi?board=winisd&action=display&thread=1087022128

I really like the look of the old enclosure, by the way.

 

[ItalynStylion 10+ year member]

Le is a measurement of the inductance of the voice coil. It's not really too important for enclosure design.
If you're trying to achieve a flat response curve, keep in mind that the you will be getting an in car boost of typically 6-12db/oct that you should to account for.

This may be helpful:

http://linearteam.proboards12.com/index.cgi?board=winisd&action=display&thread=1087022128

I really like the look of the old enclosure, by the way.

Thanks, I like it too and it's going to be hard to give up even though it is for the better.

So when you say the in car gain will be 6-12db/oct; does that mean all throughout the frequency range? I want fairly flat response because this is an all out SQ car rather than an SPL car.

Any advise on the port size?

 

[BrianChia 10+ year member]

Your car acts as an enclosure so it begins to boost output below certain frequencies. This is known as the transfer function of the vehicle. It acts like an inverted high pass filter and depending on the size of the car it may start anywhere from 70-100+hz. The larger the vehicle the lower the frequency before the transfer function starts to take effect.

This graph shows a good example of a modeled vs. actual response due to the transfer function of the vehicle.

This graph (purple line) shows the transfer function of the vehicle:

The summed responses of the measured transfer function and the modeled anechoic response (as calculated in UniBox) will be the actual in car response.

If you read the link that I posted above, you can learn to use WinISD Pro to approximate an in car response by applying a filter to simulate transfer function.

I actually just played around with the 6.5" TBs in WinISD and a 4th order bandpass looks like it would work well, although the enclosure would be fairly large.

 

[ItalynStylion 10+ year member]

I've never used WinISD. I downloaded it but I haven't tried it out yet.

I'll play around with it a little later.

 

[ItalynStylion 10+ year member]

This may be helpful:

http://linearteam.proboards12.com/index.cgi?board=winisd&action=display&thread=1087022128

I really like the look of the old enclosure, by the way.

Ok, I read that and I have no idea what it's telling me to do. I've found my driver in the database but I have no idea what do do....but I'd like to learn if you could explain it

 

[ngsm13 5,000+ posts]

I would go too large... they're only 6.5's...

How much power are they getting?

nG

 

[hazardous0388 10+ year member]

man....that install is sexy, dont ruin it =(

 

[ItalynStylion 10+ year member]

I would go too large... they're only 6.5's...
How much power are they getting?

nG

Are you saying that you wouldn't go too large?

They are getting 75rms each.

 

[ItalynStylion 10+ year member]

man....that install is sexy, dont ruin it =(

I know I know....but honestly I'm running into a problem.

I want to set m gains right and use the full voltage of my headunit. My eclipse has 8volt pre outs and the volume maxes at 80. I tuned so that 70 was pretty much my listening max; this meant I had the gain up on the subs with the non fade set really low and I had to set the Focal's gain almost all the way down to balance them. This made the Focal's sound really anemic because the gain was so low. I need to port and get my subs on par with my front stage so I can get the best SQ out of the system.

(hope I explained that right)

The ported box I make wont be plain so don't worry. It will be just as sexy I promise //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[ngsm13 5,000+ posts]

Are you saying that you wouldn't go too large?They are getting 75rms each.

Yeah, I'd go with the 1.7-1.9 and tune ~36hz...

Single 4" Aeroport. Subs towards the rear, port towards side, amp on top.

Win!

nG

 

[ItalynStylion 10+ year member]

Yeah, I'd go with the 1.7-1.9 and tune ~36hz...
Single 4" Aeroport. Subs towards the rear, port towards side, amp on top.

Win!

nG

Why not face the port the same direction as the subs?

 

[TeamPlayers]

subscribed

 

[BrianChia 10+ year member]

Yeah, I'd go with the 1.7-1.9 and tune ~36hz...
Single 4" Aeroport. Subs towards the rear, port towards side, amp on top.

Win!

nG

Probably a bad choice if you want to maintain SQ.

I ran up a sim on a 4th order design which was nearly as flat as a sealed setup but about 4-6db more efficient.