3.5 ohms into 4ohm amp

Kyrk · 2021-06-28 7:13 pm

Hello, I've build a 2-way 4 ohm speaker that goes down to 3.5 ohms at around 200hz (check the picture for the modeled impedance response). I am worried that my 4ohm amp a TDA7498E will have problems with the current peaks since its rated for 4 ohms (this is the ampAIYIMA B03 Bluetooth 5.0 Power Amplifier 160W * 2 TDA7498E Sound Amplifier Stereo Subwoofer Amplifier Altitude Bass With USB Music Player For Home Desktop Speaker Adjustable: Amazon.de: MP3 & Hifi). Should I be worried or is it ok to drive the speaker with this amp?

rayma · 2021-06-28 7:34 pm

That's fine, many speakers are much worse.

JonSnell Electronic · 2021-06-28 7:44 pm

Is your measured 3.5R impedance or resistance.
Most 4R speakers read 3 or so with a DVM.

Kyrk · 2021-06-28 8:05 pm

dc resistance is more than 4 omhs. I got the 3.5 ohms from the graph i attached (140-250 hz).