A working 3 way project all new drivers. Both the tw and mid are 92Db and the wf is 88Db.
Looking to simply boost bass it seems to lower the sensitivity of the mid closer to the wf would help.
Installed a LPad in circuit was not successful except to attenuate the high frequencies of the mid. No noticeable bass improvement.
Thinking now to just place a resistor on the mid. It would have to handle about 100 watts so a wire wound would be necessary. Researching has not given me any help selecting value. Hoping I can get some here.
Thanks
Looking to simply boost bass it seems to lower the sensitivity of the mid closer to the wf would help.
Installed a LPad in circuit was not successful except to attenuate the high frequencies of the mid. No noticeable bass improvement.
Thinking now to just place a resistor on the mid. It would have to handle about 100 watts so a wire wound would be necessary. Researching has not given me any help selecting value. Hoping I can get some here.
Thanks
I would use a discreet L-pad just before the midrange driver.
A series resistor and then a shunt resistor across the driver.
Start with around 2R series and 8R shunt, then adjust the values to taste.
You may need to adjust the midrange crossover C and/or L values also.
If you only want to use one resistor, try a 4R series to start.
Use cheaper 20W resistors until you decide on the values,
and then you can get the higher power resistors.
A series resistor and then a shunt resistor across the driver.
Start with around 2R series and 8R shunt, then adjust the values to taste.
You may need to adjust the midrange crossover C and/or L values also.
If you only want to use one resistor, try a 4R series to start.
Use cheaper 20W resistors until you decide on the values,
and then you can get the higher power resistors.
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Will in excess of 100 W of power really be delivered to the mid in your application?
What is your amplifier power?
What is your amplifier power?
Proper baffle step compensation [BSC] design to 'kill two birds with one stone' 🙂: General Speaker Related Articles
Negative. I err on the side of safety. The over all power tolerance of this project has not been calculated but I suspect it will be much more then 100 watts.
I am using a HK Citation 12. Rated at 60Watts per channel but I suspect it is much higher. I rarely pound the air any more.
Maybe some day I will do some Bi-amp on a set of speakers but right now I am enjoying the blend of two amps into different speakers. Really fills the spectrum.
Thanks
This is pretty much what I was looking for. It is giving me a few ideas to run with. Thanks.
Ordering 20W is probably a good idea. Another post down here suggests lesser values even. I have some more learning to do.
Driver efficiency is measured in DB but how can that be converted to resistance. Is there a reference?
If you put 8 ohms in series with an 8 ohm driver, you drop 6dB. (Half the voltage at the driver)
The problem is that the driver varies from 8 ohms at different frequencies. It is more consistent if you put some resistance in parallel too. An 8 ohm resistor in parallel with 8 ohm driver equals 4 ohms. 4 ohms in series with this takes it down 6dB. This way has the added benefit that the total stays at 8 ohms.
The problem is that the driver varies from 8 ohms at different frequencies. It is more consistent if you put some resistance in parallel too. An 8 ohm resistor in parallel with 8 ohm driver equals 4 ohms. 4 ohms in series with this takes it down 6dB. This way has the added benefit that the total stays at 8 ohms.
Here is an L pad calculator which allows you to enter the driver impedance in ohms and the wanted attenuation in dB:
L pad calculator - attenuation dB damping impedance decibel loudspeaker speaker voltage divider - sengpielaudio Sengpiel Berlin
It calculates both the value of the single resistor required to give the required attenuation and the values of the series and parallel resistors required to make an L pad attenuator instead.
Depending on the crossover frequencies, your midrange driver may only receive around 30% of the total amplifier power applied to your three-way speaker system.
As you are using a 60 W amplifier, then - at full volume - your midrange driver is likely to receive only around 18 W of power.
A 20 W attenuating resistor would be more than adequate in this situation.
The attached chart shows the power distribution in orchestral music. Most of the power is generated below 500 Hz. This may be extended to the distribution of power in a loudspeaker system.
Attachments
Driver ohms out at 6.6ohms. From this and your next post, a 20 Watt Shunt and Series resister will be what I will do. I am going to use 8 ohm at first. depending on the results I will have a couple at 6 & 7 ohm as well.
Thanks for the guidance.
The calculator agrees with AllenB's values for 8 ohm impedance and 6 dB of attenuation i.e. Rs = 4 ohm and Rp = 8 ohm - so can be trusted.
For a nominal impedance of 8 ohm and an attenuation of 10dB, the calculator gives Rs = 5.47 ohm and Rp = 3.7 ohm. In practice, you would choose the nearest standard resistor values to those i.e. 5.6 and 3.9 ohm respectively - again agreeing with AllenB's estimates.
For a nominal impedance of 8 ohm and an attenuation of 10dB, the calculator gives Rs = 5.47 ohm and Rp = 3.7 ohm. In practice, you would choose the nearest standard resistor values to those i.e. 5.6 and 3.9 ohm respectively - again agreeing with AllenB's estimates.
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What mid and woofer are you using? What are the cab specs for the woofer (volume, vented or sealed, tuning frequency if vented)? A 88dB (1W? 2.83V?) woofer doesn't look to be a PA driver, and often a 100W advertised woofer when placed in a suitable box will exceed x-max at only 16-32W, so thinking of having 100W to be run through the driver is a recipe for distortion or even a failure.
Ralf
Not being able to choose a suitable Lpad for a mid makes me wonder about the ability to design a crossover
Hi and thanks for taking a interest. Your questions are applicable in the over all product no doubt but.. you are changing the subject. keeping this as simple as I can to achieve what I hope to do which is to equal as best i can, the path of resistance across a frequency spectrum and I am doing this as easy and cheap as i can, for now.
If i knew what I needed for a lpad i would not have posed the question. The idea he gave will suffice. Once implemented I will report and that will happen after I get the parts. Stick around.
If i knew what I needed for a lpad i would not have posed the question. The idea he gave will suffice. Once implemented I will report and that will happen after I get the parts. Stick around.