Cheap 10inch woofer in tapped horn? what would you do?

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
figured I'd ask for peoples ideas and suggestions, I've already modelled a few boxes, but thought I'd hear what other people might do :)

also make it easier for me to keep track of the specs, which are manufacturer supplied, although I'd like to measure them for myself some time.

* Power: 300W RMS
* Peak Power: 600W
* Frequency Response: 40Hz - 1.5KHz
* Sensitivity: 87dB/1m/1w
* Fibreglass Composite Subwoofer Cone
* Vas: 26.903
* Impedance: 4 ohm
* Qms (Mechanical Factor): 3.312
* Qes (Electrical Factor): 0.478
* Qts (Total Q-Factor): 0.418
* Fs (Resonance): 45Hz

assuming we measure half the width of the surround when calculating the sd, the diameter is 20.5cm, so SD is 330cm^

re measures 4.2ohms

and most importantly, they're purdy! so I'd like to have the cones on display :eek:

An externally hosted image should be here but it was not working when we last tested it.
 
Last edited:
my, they must be stiff as hell
car woofers, surely

if they are all yours, make two line arrays, closed, and lots of Eq

Xmax ?

I don't discriminate against "car" and "home" woofers.

there really isn't a difference, they both have magnets and coils!

don't know X-Max, I'd guess somewhere around 5 - 10mm one way :p

I've currently got them modelled in a 2.4m long (total) tapped horn.

165cm^ throat, 330cm^ mouth, with the woofer 15cm from each end.

it gives a theoretical 103dB 1w down to 40Hz, but the mouth just seems way too small to yield that kind of efficiency.
 
How many drivers do you have?

You will need a very very very large horn to get 150dB@30Hz. With the 300w power rating of one driver, you'd need a starting efficiency (when horn loaded) of around 125dB (at one watt). Let's not get started on the excursion at that much power.
It sounds to me like you'll need more than one driver.

Chris
 
How many drivers do you have?

You will need a very very very large horn to get 150dB@30Hz. With the 300w power rating of one driver, you'd need a starting efficiency (when horn loaded) of around 125dB (at one watt). Let's not get started on the excursion at that much power.
It sounds to me like you'll need more than one driver.

Chris

An externally hosted image should be here but it was not working when we last tested it.
 
If room gain will add another 12dB (and corner placement is lossless) it could be done.

I would suggest four TH with four drivers each.
I landed around 336L internally per box.
S1 600 and S4 1500. Par. 320cm total length.

As you already have the drivers, go for it. You can't really beat much more performance out of them anyway.

If you didn't try to press so much SPL out of them 8 T-TQWT (with two drivers each) would be neat for a HT.
 
from playing with horns before, I don't expect any room gain, but I do expect it to lower the frequency response slightly.

I had modelled a simple, single fold 240cm horn, with eight woofers in it...

one thing I noticed though, was that if I doubled all the "S" figures, and the number of woofers, hornresp suggested that the frequency response would change, and it would play lower...

is this correct?
 
FYI:

b:)
 

Attachments

  • TDWM.JPG
    TDWM.JPG
    476.3 KB · Views: 636
  • TDWM-cont.JPG
    TDWM-cont.JPG
    737.4 KB · Views: 610
I'm considering just doing the design in black and not worrying about 30Hz and below.

An externally hosted image should be here but it was not working when we last tested it.


same power as the grey line (which is your TQWT) in 8th space, with 1 watt.

Hi,

Sorry for neglecting the 30 Hz requirement: That is IMO, a better choice for your drivers than what I came up with :eek:. See the revised simulations for closer down to ~30 Hz and promising more improved SQ performance.

How do you know when your design are within 8th-space? See the 8th-space picture?

b :)
 

Attachments

  • TDWM-music.JPG
    TDWM-music.JPG
    472.4 KB · Views: 454
  • TDWM_music_cont.JPG
    TDWM_music_cont.JPG
    723.2 KB · Views: 87
  • 8th_space.JPG
    8th_space.JPG
    124.1 KB · Views: 100
How do you know when your design are within 8th-space? See the 8th-space picture?

b :)

what do you mean by that?

I did quite like your first design, but I felt they were lacking the efficiency to reach 150dB

I was also trying to come up with a design that was simple enough to be a single fold, made from a 120cm wide piece of MDF...

I quickly scribbled this up, its not accurate, but was just a proposed idea... but to make four of these, each 4 times the height, is just a lot of work!

An externally hosted image should be here but it was not working when we last tested it.
 
what do you mean by that?[/QUOTE]

IMO,You cannot count on 100% 8th-space boundary in-band gain for a realistic design to reach 150 dB/1m using all your drivers. I think at most would be around ~140 dB (Accompanied with lot of hear-able distortion and other artifacts included too, of course).

I did quite like your first design, but I felt they were lacking the efficiency to reach 150dB

:eek: I try to support SQ in my designs and for home environment: I would never endorse SPL levels that would permanent injure a listeners ears.

b:)
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.