Tang Band Tang Band W8Q-1071F 8 X 12 box reccomendation

[permo]

Originally Posted by mdocod

After simming your driver in hornresp awhile, I'm convinced that this horn loading stuff is a lot more hype than anything. The best arrangement I could come up with produced similar efficiency and loading characteristics as the 6th order bandpass box I suggested above, however, the box would be nearly twice the size, and perform ~3db worse in maximum output compared to the 6th order bandpass configuration.

Well, the hornresp design in this example is 133 liters or so, which isn't that large and goes down to 20hz solid. I am not sure exactly how feasible this design is.

The problem with the 6th order is the 35hz to 90 hz effective passband. the gain is nice and fully appreciated, but I am looking to add some realism to movies, and 35hz isn't going to cut it.

So far the most realistic, and feasable configuration to take full adantage of my speaker design abilities is a 4.5-to 6 cubic foot ported enclusure tuned to 25-30 hz.

If i could figure out how to build the horn I would likely give that a try but as of right now, I don't have confidence in my ability to put those numbers into cutting wood.

[tb46]

Hi permo,

Post #21: "...confidence in my ability to put those numbers into cutting wood."

That is the problem, some enclosures model just fine, but the model cannot be converted into a physical reality (at least not easily). This is one of those, there is just not enough cross-sectional area to fit the drivers, and to properly fit the S34 duct length.

If you want to build something like this you may have to take a different approach. Instead of the S12 duct section you could substitue a coupling chamber (or call it: horn throat chamber), which could be sized to provide room for the drivers. You would still have to deal with the problem of where to place the S34 duct length.

I'll attach a Hornresp input as an example:

Regards,

[permo]

wow, now I see. It may not be possible to make this one happen. Bummer.

I will continue too look at my options, I am probably still -3-4 months away from finishing my theater room, so I have some time.

[tb46]

Hi permo,

To give you a general idea what this type of enclosure would look like I'll attach a drawing for a "Chambered T-TQWT" (using the TB W8-1071). You can enter the data into Hornresp, and see if you think this would be something worthwhile. To accurately model this one you would have to go into AkAbak, but I don't think the difference would be very big. By the way, if you want to combine S1 and S2 in Hornresp, you give them the same area, and set L12 to 0.01cm.

Regards,

[permo]

Originally Posted by tb46

Hi permo,

To give you a general idea what this type of enclosure would look like I'll attach a drawing for a "Chambered T-TQWT" (using the TB W8-1071). You can enter the data into Hornresp, and see if you think this would be something worthwhile. To accurately model this one you would have to go into AkAbak, but I don't think the difference would be very big. By the way, if you want to combine S1 and S2 in Hornresp, you give them the same area, and set L12 to 0.01cm.

Regards,

WOW is that COOL!!!!!

[bjorno]

Originally Posted by permo

WOW is that COOL!!!!!

Agree, Here is a crude picture showing how to deal with a OD_T-TQWT
with clearance problem at the rear driver side:

b

[permo]

Wow am I spoiled. Thank you so much.

[tb46]

Hi again,

Here is what happened, I put bjorno's numbers into a spreadsheet that I had used to calculate the cross-sectional duct heights for a symmetrical tapped horn, in other words I divided the duct height by 2. Obviously, the drivers would not fit anymore. Well, haste makes waste.

I redrew the sketch to reflect bjorno's design. I hope I got it right this time. I don't think that the taper from S1 to S2 is necessary, as the stuffing in this section can be modified to suit. I guess the little extra duct below S4 would have to be modelled in AkAbak.

Regards,

[permo]

My God you guys are good. Now to I have the courage to build it!? Why not!

[tb46]

Hi permo,

I see no reason not to build them. If you haven't yet, take a look at DrDyna's thread: Fiddling with Hornresp - Peerless 831759. He seems to be very pleased with the result.

You may want to redraw the enclosure, or if you want me to I can make whatever changes bjorno recommends, and add the additional dimensions.

Regards,