Retrofitting a tweeter switch
Retrofitting a tweeter switch
Hi all
I have a chance to buy a Omni15 Tallboy however it is wired full range. Is it possible/easy to install a switch for the tweeters??
Many thanks in advance
I have a chance to buy a Omni15 Tallboy however it is wired full range. Is it possible/easy to install a switch for the tweeters??
Many thanks in advance
Thunderbird
Terror Bass
Jack 10 Lites
Terror Bass
Jack 10 Lites
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Re: Retrofitting a tweeter switch
Piece of cake.
Add a switch on the + line leading to the tweeter from the crossover board, and you can now turn it on and off.
It will cost you a couple of quid in parts and 10 minutes of your time if you can solder, wait up, 15 minutes, because you'll need to drill a hole somewhere for the switch
Add a switch on the + line leading to the tweeter from the crossover board, and you can now turn it on and off.
It will cost you a couple of quid in parts and 10 minutes of your time if you can solder, wait up, 15 minutes, because you'll need to drill a hole somewhere for the switch
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" KL3010LF , 2 x 28" 3012LF.
WH8: x 6 with melded array wired series/parallel.
Bunter's Audio and Lighting "like"s would be most appreciated...
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" KL3010LF , 2 x 28" 3012LF.
WH8: x 6 with melded array wired series/parallel.
Bunter's Audio and Lighting "like"s would be most appreciated...
- Bill Fitzmaurice
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Re: Retrofitting a tweeter switch
Do not do that. The high pass filter must have a load, otherwise the amp could be damaged. A switch must be installed before the high pass filter, not after.Grant Bunter wrote: ↑Wed Jul 15, 2020 4:30 am Add a switch on the + line leading to the tweeter from the crossover board
Re: Retrofitting a tweeter switch
Would a potentiometer work if it was grounded?
BFM builds:
XF212
T24 BP102 24"
2x SLA's 6-5" mids, 9- gt-302's
2x AT 14" MCM 55-2421
TrT 5" MCM 55-2421
AT 18" JBL GTO804
2x OT12 flat array
2x SLA Pro 2-Alpha 6's 2-Goldwoods
2x T39 24" 3012lf
Simplex 10 BP102
XF212
T24 BP102 24"
2x SLA's 6-5" mids, 9- gt-302's
2x AT 14" MCM 55-2421
TrT 5" MCM 55-2421
AT 18" JBL GTO804
2x OT12 flat array
2x SLA Pro 2-Alpha 6's 2-Goldwoods
2x T39 24" 3012lf
Simplex 10 BP102
- Bill Fitzmaurice
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Re: Retrofitting a tweeter switch
No. It won't provide the constant impedance load that's required for the filter to function correctly. Use an LPad.
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- Posts: 6915
- Joined: Mon Nov 28, 2011 11:12 am
- Location: Ilfracombe Queensland Australia
- Contact:
Re: Retrofitting a tweeter switch
With the Omni15TB being a three way box, doesn't the woofer LP filter, and a band pass filter provide sufficient load to the amp?Bill Fitzmaurice wrote: ↑Wed Jul 15, 2020 6:42 amDo not do that. The high pass filter must have a load, otherwise the amp could be damaged. A switch must be installed before the high pass filter, not after.Grant Bunter wrote: ↑Wed Jul 15, 2020 4:30 am Add a switch on the + line leading to the tweeter from the crossover board
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" KL3010LF , 2 x 28" 3012LF.
WH8: x 6 with melded array wired series/parallel.
Bunter's Audio and Lighting "like"s would be most appreciated...
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" KL3010LF , 2 x 28" 3012LF.
WH8: x 6 with melded array wired series/parallel.
Bunter's Audio and Lighting "like"s would be most appreciated...
- Bill Fitzmaurice
- Site Admin
- Posts: 28647
- Joined: Tue May 02, 2006 5:59 pm
Re: Retrofitting a tweeter switch
What happens when there's no load to any of the three filters is that the impedance seen by the amp within that filter pass band can go very low, even approaching zero.
Re: Retrofitting a tweeter switch
Also, keep in mind that if you install a simple switch (on the positive lead between the high pass filter and the input jack) to turn the tweeter on and off, the bandpass filter on the midrange is still in play.
So the midrange driver won't even attempt to reproduce the upper highs, because of the low-pass section of the bandpass filter used on the three-way version of the Omni Tallboy.
If this is what you want, fine. But if you wish to turn off the tweeter and allow to be midrange driver to take over the highs as best it can (like the two-way version of the Omni Tallboy) Bill has designed the bandpass filter for the midrange in two sections, which could allow you to use a dpdt switch to turn off the tweeter AND bypass the low-pass section of the midrange bandpass filter.
I suspect this it what Bill intended all along, though he doesn't mention it specifically.
If you like, I'll post a wiring diagram when I get a few minutes.
So the midrange driver won't even attempt to reproduce the upper highs, because of the low-pass section of the bandpass filter used on the three-way version of the Omni Tallboy.
If this is what you want, fine. But if you wish to turn off the tweeter and allow to be midrange driver to take over the highs as best it can (like the two-way version of the Omni Tallboy) Bill has designed the bandpass filter for the midrange in two sections, which could allow you to use a dpdt switch to turn off the tweeter AND bypass the low-pass section of the midrange bandpass filter.
I suspect this it what Bill intended all along, though he doesn't mention it specifically.
If you like, I'll post a wiring diagram when I get a few minutes.
- Bill Fitzmaurice
- Site Admin
- Posts: 28647
- Joined: Tue May 02, 2006 5:59 pm
Re: Retrofitting a tweeter switch
I didn't put a switch into the mix because the LPad is far more useful.
Re: Retrofitting a tweeter switch
<the LPad is far more useful>
It is, too.
I put both switch and LPad in my Omni Tallboy 12, thinking that switching to two-way mode (no tweeter) would sound better when using distortion.
How often do I actually use distortion? Never.
How often do I turn down the LPad? Never. Even with the rudimentry passive EQ setions I use.
If I build one again, it will be without LPad and switch.
Even with flats, I strongly prefer the slight click the tweeter provides.
It is, too.
I put both switch and LPad in my Omni Tallboy 12, thinking that switching to two-way mode (no tweeter) would sound better when using distortion.
How often do I actually use distortion? Never.
How often do I turn down the LPad? Never. Even with the rudimentry passive EQ setions I use.
If I build one again, it will be without LPad and switch.
Even with flats, I strongly prefer the slight click the tweeter provides.