Fs stays the same.lower efficiency is ok in this case. The drivers are already 0.4 qts so I'm not sure what detrimental effect that cd have. Fs stays the same?
Do you have impedance measurements of those woofers? Maybe it is not necessary to use higher resistance in series with them.
What about the amplifier?
These Dayton woofers, 3 in parallel. Luckily they were thoroughly tested by Audioxpress
Dayton Audio ES180Ti-8 7" Esoteric Series Woofer 8 Ohm
Test Bench - Dayton Audio ES180Ti-8 7” High-End Midbass Woofer | audioXpress
Dayton Audio ES180Ti-8 7" Esoteric Series Woofer 8 Ohm
Test Bench - Dayton Audio ES180Ti-8 7” High-End Midbass Woofer | audioXpress
What about the amplifier?
Using an old Arcam atm but plan to upgrade to a Luxman 509x
Looks like that woofer drops to minimum of about 7.8ohm at 200Hz. Three in parallel gives 2.6ohm. If you added 1ohm series resistance that gets you to 3.6ohm which would generally be accepted as a "nominal 4ohm" design. Adding the 1ohm series resistance drops the level by 2.83dB @ 200Hz, less at frequencies where the impedance of the drivers is higher e.g. there will be virtually no change in level where each drivers impedance is >>7.8ohm such as at the resonant peak. You should sim this as it'll make quite a dramatic difference to the response.
Since two drivers gives +6dB and three drivers gives +9.5dB, you might find two drivers is a better design since you won't need to suffer any attenuation from adding excessive series resistance (the impedance is already 3.9ohm) giving flatter response.
Since two drivers gives +6dB and three drivers gives +9.5dB, you might find two drivers is a better design since you won't need to suffer any attenuation from adding excessive series resistance (the impedance is already 3.9ohm) giving flatter response.
Last edited:
thanks TMM and everyone for replies. For a couple of reasons I will still try with 3, I can see its a bit of a challenge and may not be perfect. The 20awg jantzen aircore inductor looks to be around 1.3ohm. So will trial different inductors and move the crossover point and see what works best
Last edited:
According to DIN standard, nominal 4-ohm loudspeaker should have minimum impedance higher or equal to 3.2 ohm. Inductor with 0.6 ohm resistance (normal, usual value) gives total minimum of 3.2 ohm between 150 and 400 Hz with three woofers in parallel. That is perfectly acceptable load for Arcam or Luxman amplifier, so no need for thin wire (high awg) inductor.
Anyway, I would use two, rather than three woofers in parallel.
Anyway, I would use two, rather than three woofers in parallel.
Ha, if you are designing high-end loudspeakers, than ridiculously low impedance is the most desirable feature!
lol Wilson Audio spring to mind..
Ha, if you are designing high-end loudspeakers, than ridiculously low impedance is the most desirable feature!
This is true! It makes the speakers more "discerning" of amplifier drive capability, leading to the false impression they are better in any way at producing music.
The idea goes like this: If a speaker can tell which amplifier is better, by sounding different, then it must be able to extract every iota of musical detail from a recording.
The only honest low-impedance speakers I know of are ESL's and the Apogee ribbons.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
- Home
- Loudspeakers
- Multi-Way
- thin gauge air core inductors