resistor across speaker terminals

[mcmahon48]

I was wondering what would happen doing the following with this idea
putting 6.8 ohm resistor across from the + to - on this speaker Silver Flute W14RC25-04 ohm 5-1/2" Wool Cone from Madisound idea to drop the 5db rise starting at 5khz) and what effect it would have on performance

for I would like to have 2 of these set in parallel with a 3.9 resistor in series to to Xover to stablize the impedance around 4 ohms for I know that the impedance would be lowered drastically

[richie00boy]

Don't quite follow, what's the crossover you talk about? Simply putting a resistor across the speaker terminals just makes your amp get hotter and produce more distortion. If you want to tame that bump you need a type of filter network.

[JayeSel]

Agreed - putting a resistor across the terminals would just effectively lower the loads seen by the amp, thus generating more heat at the output stage. Have you done the sums to work out how your resistor will affect the impedance seen by the amp? Ideally you'd notch out the bump before the amp, as it's a lot easier to flatten something off before you amplify it.

What's the point in amplifying something you're only going to cut again?

[Pano]

Practicality, simplicity, tradition, to name but 3.

[mcmahon48]

Knowing that I would great reduce the impedance of the circuit I would have add a 3.9 to make the circuit impedance around 4 to 5 ohm to prevent burning out the amp, I was trying some way to smooth out the 5 db rise I am also using a hybrid box which is half box and half sphere to get rid of the 5 db rise starting at 4 khz

[richie00boy]

What you propose will just reduce the level from the driver across it's whole band.

[alan-1-b]

For Parallel connected woofers, use 8 ohm specification drivers ...
Silver Flute do manufacture such.
If you use the 4 ohm spec woofers then connect them in electrical Series,
then you will have a safe load for your amp,
and you will not have to connect a resistor in Series with the drivers.
A resistor in Series with woofers ruins their Transient Response !
Result will be very uncontrolled or loose bass performance.

For the 6.8 ohm Parallel resistor idea, connect a 5.6uF capacitor in Series with the resistor, and connect the resulting RC Series circuit in Parallel with your total woofer pair if 4 ohm + 4 0hm.
The cap may need to be a little larger than 5.6 ... perhaps 6.2 or 6.8uF ... one would have to test and measure the result to know the optimum value,
and it may depend on the type of crossover filter you are using for the woofers also.

If you are using 8 ohm//8 ohm woofers, then use a 3.9 ohm resistor - of minimum 10 watts rating, but 20 watts better - and a 12 uF capacitor.