What will be the difference in spl if I have one 8ohm 89db sensitivity driver powered by 50w
Vs
2 4ohm drivers in series(total 8ohm) with sensitivity of 86db
Vs
2 4ohm drivers in series(total 8ohm) with sensitivity of 86db
I think there would be difference in the resulting radiation pattern. Two of those would sound taller / wider when compared to the lone driver I guess. Of course, it also depends on the spacing between their centres.
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You will have less thermal compression with the two driver setup and double the displacement giving a 6dB increase in displacement limited power handling. Now if these are 15" drivers that are not being driven to thier displacement limits with 50W this is a non issue, if they are 5" drivers this is a big benefit for the dual driver configuration.
Forgot to mention it's 6" mid bass drivers in 2 way system
They will see 80watts per speaker maximum
So 80watts 89db 1 8 ohm driver
Vs 80watts 86db 2 4ohm in series (8 ohm total)
Thanks for feedback
Basically I am looking to replace an 8ohm 89db driver with 2 4ohm 86db drivers
Most of other parameters are super close except impedance.
They will see 80watts per speaker maximum
So 80watts 89db 1 8 ohm driver
Vs 80watts 86db 2 4ohm in series (8 ohm total)
Thanks for feedback
Basically I am looking to replace an 8ohm 89db driver with 2 4ohm 86db drivers
Most of other parameters are super close except impedance.
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As far as I am aware 2 x 4ohm speakers is series at 86dB/W/m will be still be 86dB/W/m but now 8 ohms but double the radiating area obviously.
So if I have volume level on receiver that makes 80 watts
it will be 40watts per each 4ohm speaker . 40+40
But because 2 speakers are working (moving air) will it produce same spl as 1 8 ohm speaker at 80 watts
Or will it be the same because speakers in series are using 40watts each
it will be 40watts per each 4ohm speaker . 40+40
But because 2 speakers are working (moving air) will it produce same spl as 1 8 ohm speaker at 80 watts
Or will it be the same because speakers in series are using 40watts each
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One 8-ohm speaker with 89dB/2.83V/1m sensitivity will be louder than two 4-ohm speakers in series, each with 86dB/2.83V/1m sensitivity.
Providing the same 80 W input, the first one will reach 108 dB/1m maximum SPL, and the second one (the double drivers) only 105 dB/1m. This 3 dB difference is big enough to overcome somewhat bigger power compression of the single speaker.
Providing the same 80 W input, the first one will reach 108 dB/1m maximum SPL, and the second one (the double drivers) only 105 dB/1m. This 3 dB difference is big enough to overcome somewhat bigger power compression of the single speaker.
If you want to compare SPL for two drivers you need to use the correct unity.
This is dB/2.83V and not db/1W. This is because what the driver draws from the amp, at constant voltage, depends on its impedance: a 8 Ohm driver draws 1W with 2.83V, whereas a 4 Ohm one draws 2W.
So if your SPL numbers are for 2.83V, the 8 Ohm driver is rated at 89dB and the 4 Ohm one is rated at 86dB. If your SPL numbers are for 1W, then the 8 Ohm driver is also rated at 89dB/2.83V, but now the 4 Ohm driver is also rated at 89dB/2.83V, because 1W is drawn at only 2.0V instead of 2.83V.
Either way, connecting in series two drivers don't change the sensitivity in dB/2.83V, what you gain is double the area, and this will provide a higher max SPL before exceeding excursion.
Last note about the amp rating and driver excursion (xmax). Almost any "normal" driver will exceed xmax at a voltage way lower than what a "normal" amp can provide. A 50W rated amp will easily overdrive your mid-bass. If the same mid-bass is used only for mid duties, then this is another story.
Ralf
This is dB/2.83V and not db/1W. This is because what the driver draws from the amp, at constant voltage, depends on its impedance: a 8 Ohm driver draws 1W with 2.83V, whereas a 4 Ohm one draws 2W.
So if your SPL numbers are for 2.83V, the 8 Ohm driver is rated at 89dB and the 4 Ohm one is rated at 86dB. If your SPL numbers are for 1W, then the 8 Ohm driver is also rated at 89dB/2.83V, but now the 4 Ohm driver is also rated at 89dB/2.83V, because 1W is drawn at only 2.0V instead of 2.83V.
Either way, connecting in series two drivers don't change the sensitivity in dB/2.83V, what you gain is double the area, and this will provide a higher max SPL before exceeding excursion.
Last note about the amp rating and driver excursion (xmax). Almost any "normal" driver will exceed xmax at a voltage way lower than what a "normal" amp can provide. A 50W rated amp will easily overdrive your mid-bass. If the same mid-bass is used only for mid duties, then this is another story.
Ralf