{"v":"2.0","page_type":"product","title":"ALPHA-12A * Nominal Basket Diameter: 12-in 305 mm.* Nominal Impedance: 8 Ohms.* Power Rating:* Watts: 150 W.* Music Program: 300 W.* Resonance: 49 Hz.* Usable Frequency Range: 51 Hz - 4.3 kHz.* Sensitivity: 95.6 dB.* Magnet Weight: 20 oz..* Gap Height: 0.25-in 6.4 mm.* Voice Coil Diameter: 1.5-in 38 mm.* Thiele & Small Parameters.* Resonant Frequency (fs): 49 Hz.* DC Resistance (Re): 6.3 Ohms.* Coil Inductance (Le): 0.79m H.* Mechanical Q (Qms): 6.53.* Electromagnetic Q (Qes): 0.88.* Total Q (Qts): 0.77.* Compliance Equivalent Volume (Vas): 121.5 liters / 4.29 cu.ft..* Peak Diaphragm Displacement Volume (Vd): 125 cc.* Mechanical Compliance of Suspension (Cms): 0.32 mm/N.* BL Product (BL): 8.5 T-M.* Diaphragm Mass Inc. Airload (MMs): 33 grams.* Efficiency Bandwidth Product (EBP): 56.* Maximum Linear Excursion (Xmax): 2.4 mm.* Surface Area of Cone (Sd): 519.5 cm2.* Maximum Mechanical Limit (Xlim): 6.6 mm.-----------------------------------Recommended Enclosure Volume;* Sealed: 17-22.7 liters / 0.6-0.8 cu.ft..* Vented: 56.6-113.3 liters / 2-4 cu.ft..* Driver Volume Displaced: 0.063 cu.ft. / 1.78 liters.* Overall Diameter: 12.26-in 311.4 mm.* Baffle Hole Diameter: 11.06-in 280.9 mm.* Front Sealing Gasket: Yes.* Rear Sealing Gasket: Yes.* Mounting Holes Diameter: 0.25-in 6.4mm.* Mounting Holes B.C.D.: 11.71-in 297.4mm.* Depth: 4.73-in 120.1 mm.* Net Weight: 5.3 lbs 2.4 kg.* Shipping Weight: 7.4 lbs 3.36 kgs.* Materials of Construction.* Coil Construction: Copper voice coil.* Coil Former: Polyimide former.* Magnet Composition: Ferrite magnet.* Core Details: Vented & extended core.-----------------------------------.* Basket Materials: Pressed steel basket.* Cone Composition: Paper cone.* Cone Edge Composition: Cloth cone edge.* Dust Cap Composition: Solid composition felt dust cap.","breadcrumbs":[{"label":"Home","href":"/python/html6/index.html"},{"label":"Brands","href":"/python/html6/menu_brand_index/menu_brand_index_brands_87101ba214.html"},{"label":"Eminence","href":"/python/html6/menu_brand_products/1000/48000/menu_brand_products_EMINENCE_1_b3ca5cc26e.html"},{"label":"Alpha-12A","href":null}],"content":{"product":{"mpn":"Alpha-12A","manufacturer":"Eminence","brand":"Eminence","brand_url":"/python/html6/menu_brand_products/1000/48000/menu_brand_products_EMINENCE_1_b3ca5cc26e.html","title":"ALPHA-12A * Nominal Basket Diameter: 12-in 305 mm.* Nominal Impedance: 8 Ohms.* Power Rating:* Watts: 150 W.* Music Program: 300 W.* Resonance: 49 Hz.* Usable Frequency Range: 51 Hz - 4.3 kHz.* Sensitivity: 95.6 dB.* Magnet Weight: 20 oz..* Gap Height: 0.25-in 6.4 mm.* Voice Coil Diameter: 1.5-in 38 mm.* Thiele & Small Parameters.* Resonant Frequency (fs): 49 Hz.* DC Resistance (Re): 6.3 Ohms.* Coil Inductance (Le): 0.79m H.* Mechanical Q (Qms): 6.53.* Electromagnetic Q (Qes): 0.88.* Total Q (Qts): 0.77.* Compliance Equivalent Volume (Vas): 121.5 liters / 4.29 cu.ft..* Peak Diaphragm Displacement Volume (Vd): 125 cc.* Mechanical Compliance of Suspension (Cms): 0.32 mm/N.* BL Product (BL): 8.5 T-M.* Diaphragm Mass Inc. Airload (MMs): 33 grams.* Efficiency Bandwidth Product (EBP): 56.* Maximum Linear Excursion (Xmax): 2.4 mm.* Surface Area of Cone (Sd): 519.5 cm2.* Maximum Mechanical Limit (Xlim): 6.6 mm.-----------------------------------Recommended Enclosure Volume;* Sealed: 17-22.7 liters / 0.6-0.8 cu.ft..* Vented: 56.6-113.3 liters / 2-4 cu.ft..* Driver Volume Displaced: 0.063 cu.ft. / 1.78 liters.* Overall Diameter: 12.26-in 311.4 mm.* Baffle Hole Diameter: 11.06-in 280.9 mm.* Front Sealing Gasket: Yes.* Rear Sealing Gasket: Yes.* Mounting Holes Diameter: 0.25-in 6.4mm.* Mounting Holes B.C.D.: 11.71-in 297.4mm.* Depth: 4.73-in 120.1 mm.* Net Weight: 5.3 lbs 2.4 kg.* Shipping Weight: 7.4 lbs 3.36 kgs.* Materials of Construction.* Coil Construction: Copper voice coil.* Coil Former: Polyimide former.* Magnet Composition: Ferrite magnet.* Core Details: Vented & extended core.-----------------------------------.* Basket Materials: Pressed steel basket.* Cone Composition: Paper cone.* Cone Edge Composition: Cloth cone edge.* Dust Cap Composition: Solid composition felt dust cap.","description":"","attributes":[{"name":"Brand name","values":[{"value":"Eminence","url":"/python/html6/menu_attr_pair/1000/267000000/267543000/menu_attr_pair_Brandname_Eminence_1_65327d396c.html"}],"name_url":"/python/html6/menu_attr_pair/1000/267000000/267543000/menu_attr_pair_Brandname_Eminence_1_65327d396c.html"},{"name":"Manufacturer name","values":[{"value":"Eminence","url":"/python/html6/menu_attr_pair/1000/55000000/55194000/menu_attr_pair_Manufacturername_Eminence_1_64d31a617c.html"}],"name_url":"/python/html6/menu_attr_pair/1000/55000000/55194000/menu_attr_pair_Manufacturername_Eminence_1_64d31a617c.html"},{"name":"Manufacturer","values":[{"value":"Eminence","url":"/python/html6/menu_attr_pair/1000/266000000/266129000/menu_attr_pair_Manufacturer_Eminence_1_bc1ac99fa2.html"}],"name_url":"/python/html6/menu_attr_pair/1000/266000000/266129000/menu_attr_pair_Manufacturer_Eminence_1_bc1ac99fa2.html"}],"images":[],"distributors":[{"name":"Walmart","sku":"31357815","url":"https://www.walmart.com/ip/12-in-Pro-Mid-Bass-Speaker-300W-Max-8-ohms-w-Copper-voice-coil/31357815","pricing":[{"quantity":1,"price_usd":71.55}],"stock":{"available":false,"quantity":null,"lead_time_days":null},"moq":1,"multiple":1,"image":"https://i5.walmartimages.com/asr/96d4e5ad-29d7-4896-94cc-3b705a317785_1.eda2ae4885d28ce2b29bf60662729b14.jpeg?odnHeight=450&odnWidth=450&odnBg=FFFFFF"}],"amazon":{"available":false,"products":[]},"metadata":{"generated_date":"2026-09-16","last_updated":"2026-09-16","data_sources":["Walmart"],"completeness":0.55,"version":"1.2"}}},"pagination":null,"nav":{"home":"/python/html6/index.html","brands":"/python/html6/menu_brand_index/menu_brand_index_brands_87101ba214.html","parts":"/python/html6/menu_part_index/menu_part_index_parts_909e6bf0ca.html","attributes":"/python/html6/menu_attr_index/menu_attr_index_attributes_d7f67a250d.html"}}