Quick tweeter/horn protection?

[Hat Alto]

Can I protect tweeter and/or horn by soldering a cap in the + lead to the driver? This is cause I changed the xover the old tweeter was getting almost no signal. System has a mid horn that goes pretty high + tweeter.

Just need to know these drivers are safe from overload, what cap please?

These new tweeters the same signal as the woofer (I think):

These mid horns now have L pad but use orig feed from xover:

Sounding really good to me, can attenuate the horns nicely for pleasing blend with Dayton Silky type tweeter.Just want to be sure the drivers are safe. Put a cap on the pos lead to ea driver for safety?

 

[petehall347]

if they are piezo a resistor in series will protect them

 

[westend]

Yes, what is the crossover point?

 

[Hat Alto]

I think the xover freq were 3500 and whopping 17Khz to the old phenolic tweeter. That tweet was near silent and the horn was too honky so I swapped in a Dayton tweeter and wired the horn thru the L-pad to control it.

Here is orig schematic:

Modified to this:

This got me sound I could use out of the new silkie - it's wired to that blu lead at the top r. on the schematic. Q: Is that same as what the woofer is getting? Should I protect the tweeter w a resistor or cap? Please advise.

10" woofer, "Biconic horn mid" and now a Dayton tweeter.

 

[dumptruck]

A cap around 8uF or smaller in series will protect the tweeter just fine, but there is potential for very low system impedance where it overlaps with the mid. A 10W 2Ω resistor in series as well would reduce that chance if you can spare the sensitivity. That's a very hard diagram to read... It looks like the blue is in series with a parallel 0.5mH+16uF pair? That would just act like a deep notch filter... Oh wait, then there's a series 5.7uF+.375mH in parallel with the tweeter, which would make another notch... I don't get it. Maybe they are just filtering the woofer with resonance notches, or maybe I'm reading it wrong.

 

[Hat Alto]

Thanks for taking a look and commenting. I think it an unusual circuit design as orig built. Is a B.I.C. Venturi Formula 4. The orig tweeter produced near zilch, it was on a yellow lead from that .5 cap (taped that off). I put in a Dayton tweet that runs like the mid-horn (I think) and used the L Pad to tame the horn. Sounds good and getting better as I adjust the horn but: I need to protect the tweeter and system from low impedance as you say.

So an 8uF cap + 10w 2Ω resistor in series is all I need for safety? By "if you can spare the sensitivity" do you mean the tweeter would produce less sound? I can just attenuate it up to taste then? Thanks.

 

[dumptruck]

I mean the resistor will lower the tweeter level. Connect the blue lead straight to the input (not counting the new parts to be added in series). 8uF would be around 3kHz 1st order, which may be far too low, depending on what the mid is up to, but if that comes close to meeting the woofer you could probably do away with the mid.

 

[Hat Alto]

OK - I am getting you. Does a 10w 1Ω resistor work for that? I have a couple.

 

[dumptruck]

You could put them in series for 2Ω (1Ω>1Ω>cap>tweeter). You want non-inductive resistors, ideally. I hope it goes without saying that I make no guarantees about this advice with regard to the safety of your speaker parts or amps, although I'm pretty sure I have given conservative tips here .

 

[westend]

Old Zilch told me to use a capacitor that was two octaves below the crossover point for protecting the tweeter. This was not to establish the crossover point but used as protection. That would be around 22uf for a 3500 hz crossover point, if my math is correct.