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Mach 5 Audio FTW-LTE-21

21.5" · 4 Ω · 450 W · 92.8 dB · datasheet ↗

Thiele-Small parameters

Nominal size21.5"
Impedance4 Ω
Fs19.8 Hz
Qts0.643
Qes0.7
Qms7.92
Vas526.1 L
Sd1640.3 cm²
Xmax10 mm
Re3.9 Ω
Bl17.9 T·m
Mms463.2 g
Pe450 W
Sensitivity92.8 dB

Alignment hint

EBP28 · sealed
Sealed Vb (Qtc ≈ 0.71)≈ 2513.1 L

EBP < 50: favours a sealed (closed) alignment.

Rules of thumb from T/S parameters only. Verify against a real simulation before cutting wood.

Substitute candidates

DriverFs (Hz)QtsVas (L)Xmax (mm)Sens (dB)FitNotesCompare
Fane COLOSSUS 24 BASS RIPOLE21.1 +1.30.7 +0.06503.3 -22.812.7 +2.790.1 -2.7close8 Ω vs 4 Ω: amp load changes+
CSS Audio Maelstrom 21 DVC by Exodus Audio16.3 -3.50.389 -0.25605 +78.916.3 +6.393 +0.2usable+
Mach 5 Audio FTW2119.7 -0.10.378 -0.26499.9 -26.27.5 -2.595.8 +3usableXmax 7.5 mm < 10 mm: lower excursion-limited SPL+
MTX Audio T9922-4416.8 -30.539 -0.1239.1 -28722.2 +12.291.5 -1.3risky2 Ω vs 4 Ω: amp load changes+
Pyle Audio PDW2125022.4 +2.60.331 -0.31703.8 +177.79 -196.2 +3.4risky8 Ω vs 4 Ω: amp load changes · Xmax 9 mm < 10 mm: lower excursion-limited SPL+
RCF LF 21X45128 +8.20.369 -0.27385 -141.113 +397 +4.2risky8 Ω vs 4 Ω: amp load changes+
RCF LF 21N40130 +10.20.378 -0.26374 -152.110.6 +0.698 +5.2risky8 Ω vs 4 Ω: amp load changes+
MCM Electronics 55-298525.9 +6.10.38 -0.26705 +178.96.9 -3.197.6 +4.8risky8 Ω vs 4 Ω: amp load changes · 300 W vs 450 W: lower power handling · Xmax 6.9 mm < 10 mm: lower excursion-limited SPL+
LaVoce SAF214.5030 +10.20.435 -0.21267 -259.111.6 +1.695.6 +2.8risky8 Ω vs 4 Ω: amp load changes+
LaVoce SAF214.50 vp30 +10.20.401 -0.24311 -215.111.6 +1.696.4 +3.6risky8 Ω vs 4 Ω: amp load changes+

Compare the closest 3 against the FTW-LTE-21 →

Ranked on parameter similarity only (Qts, Fs, Vas, Xmax, sensitivity). Same nominal size required. A hint, not a simulation, model the swap before cutting or buying.

Used in enclosures (0)

No enclosure in the catalog uses this driver yet.