Iconic Speakers 704-8A

15" · 8 Ω · 140 W · 99.7 dB · datasheet ↗

Thiele-Small parameters

Nominal size	15"
Impedance	8 Ω
Fs	30.9 Hz
Qts	0.262
Qes	0.27
Qms	8.49
Vas	463 L
Sd	825 cm²
Xmax	5.1 mm
Re	6.8 Ω
Bl	16.3 T·m
Mms	54.7 g
Pe	140 W
Sensitivity	99.7 dB

Alignment hint

EBP	114 · ported
Sealed Vb (Qtc ≈ 0.71)	≈ 73.7 L

EBP > 100: favours a ported (bass-reflex) alignment.

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

Substitute candidates

Driver	Fs (Hz)	Qts	Vas (L)	Xmax (mm)	Sens (dB)	Fit	Notes	Compare
Supravox 400 GN-B	28.5 -2.4	0.272 +0.01	450 -13	5 -0.1	98.6 -1.1	close	Xmax 5 mm < 5.1 mm: lower excursion-limited SPL	+
Altec 515-8LF	27.4 -3.5	0.255 -0.01	470.1 +7.1	5.1 =	98.4 -1.3	close		+
Great Plains Audio 515-8LF GPA	27.4 -3.5	0.255 -0.01	470.1 +7.1	5.1 =	98.4 -1.3	close		+
Great Plains Audio 604-8H-II	30.9 =	0.262 =	463 =	3.8 -1.3	101.2 +1.5	close	100 W vs 140 W: lower power handling · Xmax 3.8 mm < 5.1 mm: lower excursion-limited SPL	+
Supravox 400 GMF PRO	32 +1.1	0.263 =	370 -93	4.8 -0.3	99.4 -0.3	close	Xmax 4.8 mm < 5.1 mm: lower excursion-limited SPL	+
Benett 15.200 Z/N	32.9 +2	0.265 =	344 -119	5 -0.1	100.1 +0.4	close	Xmax 5 mm < 5.1 mm: lower excursion-limited SPL	+
Crites Speakers CW1526	26.3 -4.6	0.263 =	506.3 +43.3	7 +1.9	101.1 +1.4	close	4 Ω vs 8 Ω: amp load changes	+
Crites Speakers CW1526C	26.3 -4.6	0.263 =	506.3 +43.3	7 +1.9	101.1 +1.4	close	4 Ω vs 8 Ω: amp load changes	+
Beyma SM115/N	29 -1.9	0.291 +0.03	430 -33	7.3 +2.2	98.3 -1.4	close		+
Focal AUDIOM 15	32.5 +1.6	0.236 -0.03	379.7 -83.3	6 +0.9	100.4 +0.7	close		+

Compare the closest 3 against the 704-8A →

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.