Altec 421 Bass & PA Speaker Pair - USA, 1980s - 15 Inch 150W 4 Ohm, Mint Condition, straight from my vintage Jordan 2x15 californian cab - Paired with 13 Microphones from All Eras

These Altec 421 bass and PA speakers, sourced from a matched pair generously passed down by my godfather who gigged locally in the 1980s, are in mint condition and installed in a vintage 2x15 Jordan Electronics cab from the early 70s. They handle bass gracefully, while also excelling with low-overdriven guitar tones, making them ideal for doom-style guitar setups. With the right filters and compression, they could even integrate into a serious home hi-fi rig, although the primary focus here is tone for live and recording use. Replacing my old Peavey alnico blackbacks, these Altecs offer far more flexibility without losing the touch-sensitive, compressed character that makes alnico speakers special. The tonal signature is dark yet articulate, providing a solid foundation for guitar, bass, and even low-frequency PA applications. They respond well to amp push, giving natural saturation and organic compression, while retaining detail and clarity across the frequency spectrum. Microphones (full specs): AKG D70, Dynamic, 1980s–1990s, Austria, 620 Ω Akai ADM 65, Dynamic, 1980s, Japan, 600 Ω Audiojap UMC7103/1P, Electret, 1980s, Japan, 600 Ω Behringer B 906, Dynamic, 2019, China, 600 Ω Beyerdynamic M 550 LM, Dynamic, 1970s, West Germany, 500 Ω Blaupunkt CR 4073, Dynamic, 1970s, Germany, impedance unknown Marantz MPM 1000, Condenser, 2010s, China, 200 Ω Philips N8306, Dynamic, 1969, Europe, 500 Ω Realistic Highball 2, Dynamic, 1973, Japan, 600 Ω Sony MTL F 96, Dynamic, 1964, Japan, 600 Ω Technics RP 3125E, Electret, 1970s, Japan, 600 Ω Telefunken TD26, Dynamic, 1969, Europe, 750 Ω Uher M 516, Dynamic, 1969, Germany, 500 Ω Each speaker is carefully prepared before capture, ensuring optimal performance and consistency. Speakers undergo a minimum one-hour cycle of white, pink, and brown noise, pushing them to the point of mechanical rattling to minimize unwanted artifacts during recording. These sessions are interrupted with sine wave cycles to further evaluate speaker behavior and maintain sonic integrity. All microphones are kept in a dust-free, dark environment and maintained regularly to guarantee accuracy. During recording, a 30-second sine sweep is used. The signal passes through a neutral preamp, a linear power amplifier, the reliable Fosi Audio V1.0G, and then to the speaker, with all microphones powered by a Behringer MIC500 USB equipped with a Brimar 12AU7 WA tube. Noise removal is applied only when necessary to preserve the original sound. Post-processing is performed meticulously. Files are normalized at -3 dB, DC offset is removed, and Voxengo Deconvolver is applied with MP transform. The resulting IRs are normalized again to -0.3 dB, producing clean, consistent, and high-fidelity captures. This methodology ensures every speaker and microphone combination is faithfully represented, providing reliable and professional-quality impulse responses for all applications.