Lot # 78 - KOSS Model MS503 Car Stereo Compact Disc Player – Sealed New Old Stock

Opening Bid : $ 5.00
Start Date/Time: 05-May-2026 7:00:00 AM
End Date/Time: 12-May-2026 8:17:00 PM
Current bid:

$5.00

Highest bidder:

Dem0s

Auction has ended

Description :

Factory‑sealed KOSS MS503 in‑dash car stereo compact disc player with digital AM/FM tuner, preserved in its original early‑2000s retail packaging. This model represents KOSS’s mobile‑audio line from the period, featuring bilingual English/French printing consistent with its distribution at the time.

The MS503 delivers a 40‑watt system output (10 watts x 4 channels) and supports standard front‑loading CD playback along with AM/FM radio operation. Period documentation for this model includes the following technical specifications:

  • 12V DC negative‑ground power supply

  • 20 AM/FM station presets

  • Seek/manual tuning and band selection

  • Tone controls: ±10 dB bass at 100 Hz; ±10 dB treble at 10 kHz

  • Front‑loading CD mechanism with standard playback functions

  • Balance and fader controls

The box remains fully sealed, with panels showing product features, branding, and system details. Packaging exhibits expected age‑related storage wear but remains intact and unopened, making this a strong example of true New Old Stock car audio from the early 2000s.

Ideal for collectors of KOSS brand history, retro automotive electronics, or those curating period‑correct installations with original sealed packaging.




Dimensions : 11 in L x 9 in W x 4 in H

Auction History

Highest bidder is Dem0s

Date Bid User
08-May-2026 6:37:57 PM $5.00 Dem0s

PAYMENT DETAILS

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We make every effort to describe lot items as accurately as possible. Expect normal signs of wear associated with antiques, vintage, and used items. We do not list every flaw. All items are sold AS IS WHERE IS. No refunds or returns. Sound Estate Company does not guarantee the working order of any clock, watch, electronic or mechanical device. Dimensions given may be approximate.

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