BOSE 4401 PREAMPLIFIER ORIGINAL PROMOTIONAL SALES AD LEAFLET M079y | eBay
BOSE 4401 PREAMPLIFIER ORIGINAL PROMO GLOSSY BLACK AND WHITE PHOTO AD M961x | eBay
Lefson Repair - BOSE-4401 - Solid State Four Channel Preamplifier. Year 1975. We replaced some components, the 4 gang volume potentiometer, and cleaned some contacts. https://www.lefson.com/fr/reparation.php | Facebook
Bose 4401 Quadro Pre Amplifier for sale.
1970s Bose 1801 Power Amp & Preamp 4401 - $1200 (santa barbara) | Electronics For Sale | Santa Barbara, CA | Shoppok