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Two round plastic speakers in a pair, 4021 model

Ruth's sister

Ruth's sister 4021 4 Ω 3 W speaker pair

SKU CH-7QG9-B7KRD

Two-piece 4 Ω 3 W full-range speaker set with 99-10000 kHz response and 89 dB sensitivity for notebook DIY audio

  • Stereo sound from a matched pair of 4021 drivers
  • Full-range 99-10000 kHz response covers the audible band
  • 4 Ω 3 W rating suits low-power notebook amplifiers
  • 89 dB sensitivity delivers clear output from modest power
  • Round plastic cabinets with paper diaphragms for lightweight DIY installs

Pair of 4021 4 Ω full-range drivers

Two 4021 moving-coil loudspeakers are supplied in a single pack, each rated at 4 ohms impedance and 3 watts continuous power. The round coaxial-composite cones use paper diaphragms and are housed in plastic cabinets. They are intended for home hi-fi use or as wired DIY replacements in notebook computers and similar electronic equipment.

Sustained output within the 3 W rating

Rated input power is below 25 watts, so the drivers operate comfortably at their nominal 3 W level without thermal compression. The full-range frequency characteristic covers 99 Hz to 10 kHz with omnidirectional directivity, maintaining consistent dispersion during extended listening sessions. Sensitivity of 89 dB ensures adequate volume from modest amplifier power.

4 Ω impedance matches compatible amplifiers

The 4 ohm nominal impedance is the critical specification for amplifier pairing; the connected amplifier must be stable into a 4 Ω load to deliver the rated 3 W without distortion or protection shutdown. Channels are listed as 5 (4.1), indicating multi-channel system integration is possible when the amplifier supports that configuration.

How it compares

Measured against everything we stock in Worldwide Power Cords, at today’s prices. Recalculated every night.

Price $7.99
Cheaper than about 80% of the 1,208 comparable items (median $9.99).

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Specifications

No published specifications for this item yet.

Questions about this item

How much power do the 4021 speakers draw during all-day use?

The input power is under 25 W and the rated output is 3 W, so continuous draw stays very low.

What must I already have to connect these 4 Ω drivers?

You need an amplifier or device with Euroblock terminals that can drive a 4 Ω load at 3 W per channel.

Will the 89 dB sensitivity match my older amp without volume issues?

At 89 dB sensitivity the pair works well with typical vintage or modern amps; no extra gain staging is required.

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