I'm looking to build a pair or low-ish profile two way bookshelf speakers. I possibly intend to wall mount them.
I've built up the crossovers on VituixCAD and I've noticed that the impedance is hitting a low 2ohms at about 4khz. Is this going to be a problem for driving them?
I'm currently using an old Onkyo TX-SR705 amp with certainly is fine with 6 ohm speakers but maybe wouldn't do so well with 4 ohm?
My drivers are:
Tweeter - Dayton Audio RST28A-4
Mid/Bass - Dayton ND105-4
Please see the crossover image.
Crossover Only: dayton-pc-speaker-crossover-diagram — ImgBB
Crossover + Graphs: dayton-pc-speaker-crossover — ImgBB
*EDIT for different picture link*
I've built up the crossovers on VituixCAD and I've noticed that the impedance is hitting a low 2ohms at about 4khz. Is this going to be a problem for driving them?
I'm currently using an old Onkyo TX-SR705 amp with certainly is fine with 6 ohm speakers but maybe wouldn't do so well with 4 ohm?
My drivers are:
Tweeter - Dayton Audio RST28A-4
Mid/Bass - Dayton ND105-4
Please see the crossover image.
Crossover Only: dayton-pc-speaker-crossover-diagram — ImgBB
Crossover + Graphs: dayton-pc-speaker-crossover — ImgBB
*EDIT for different picture link*
Last edited:
I am struggling to read that crossover, my friend.
You'd do better to upload the circuit to the forum with the paperclip tool in the reply box.
Keep it reasonable size, around 640x480 jpeg. Forget the graphs for now.
Looks to me like you need a bigger bass coil as a start. Should sort out the impedance.
You'd do better to upload the circuit to the forum with the paperclip tool in the reply box.
Keep it reasonable size, around 640x480 jpeg. Forget the graphs for now.
Looks to me like you need a bigger bass coil as a start. Should sort out the impedance.
For a 4 ohm midbass, I'd try 1mH bass coil and about 10uF capacitor. Should look better.
The tweeter circuit surprises me. I'd expect more resistance in front with a 4" 86dB midbass, which isn't very loud usually.
The tweeter circuit surprises me. I'd expect more resistance in front with a 4" 86dB midbass, which isn't very loud usually.
That definitely gives better impedance but I can't seem to get a nice response as the midbass is rolling off far too early.
I wonder if that LCR notch on the midbass is causing problems?
Eekels' Mini
This is an 8 ohm circuit, but it drops impedance a lot.
With 4 ohms, I think you can't use an LCR notch:
Vifa PL14WJ-
Troels keeps it simple LC filter with the 4 ohm D'Appolito circuit. Hard to say if you can apply a notch to the metal driver. Converting an 8 ohm circuit to 4 ohms usually involves halving coils and resistors and doubling capacitors. The R2604 here is a 4 ohm tweeter, so that might work with some level adjustment.
Eekels' Mini
This is an 8 ohm circuit, but it drops impedance a lot.
With 4 ohms, I think you can't use an LCR notch:
Vifa PL14WJ-
Troels keeps it simple LC filter with the 4 ohm D'Appolito circuit. Hard to say if you can apply a notch to the metal driver. Converting an 8 ohm circuit to 4 ohms usually involves halving coils and resistors and doubling capacitors. The R2604 here is a 4 ohm tweeter, so that might work with some level adjustment.
Thanks.
I've had a look into these and done some googling and come up with the following:
Diagram: dayton-pc-speaker-crossover-diagram2 — ImgBB
Diagram with graphs: dayton-pc-speaker-crossover2 — ImgBB
What do you think?
If the speaker goes as low as 4ohms does that make it a 4 ohm speaker? Or is it an average value?
If the speakers end up being 4 ohms will my av/amp not be safe to power them?
I've had a look into these and done some googling and come up with the following:
Diagram: dayton-pc-speaker-crossover-diagram2 — ImgBB
Diagram with graphs: dayton-pc-speaker-crossover2 — ImgBB
What do you think?
If the speaker goes as low as 4ohms does that make it a 4 ohm speaker? Or is it an average value?
If the speakers end up being 4 ohms will my av/amp not be safe to power them?
Thanks, yes I hadn't thought about that. I'm clearly still learning about crossovers, speakers etc
I've had a play and I think it seems a bit better. Any thoughts?
Diagram: dayton-pc-speaker-crossover-diagram3 — ImgBB
Diagram with graphs: dayton-pc-speaker-crossover3 — ImgBB
I've had a play and I think it seems a bit better. Any thoughts?
Diagram: dayton-pc-speaker-crossover-diagram3 — ImgBB
Diagram with graphs: dayton-pc-speaker-crossover3 — ImgBB
You seem to be struggling to bring that treble down, but you're doing the right thing. Find a useful tweeter filter damping level by varying the components and resistor as they sometimes oppose each other. Or, add a parallel resistor with the tweeter.
Okay, thanks for the input. Hopefully this looks better.
Diagram: dayton-pc-speaker-crossover-diagram4 — ImgBB
Diagram with graphs: dayton-pc-speaker-crossover4 — ImgBB
Diagram: dayton-pc-speaker-crossover-diagram4 — ImgBB
Diagram with graphs: dayton-pc-speaker-crossover4 — ImgBB