Astrolith vs Holocene: which needs more amplifier?

The Campfire Audio Astrolith is 8.2Ω at 100.1 dB/mW; the Campfire Audio Holocene is 9Ω at 94.0 dB (no figure from the maker at all). This page covers what they ask of an amplifier, not how they sound.

The Holocene needs 6.1 dB more than the Astrolith to reach the same loudness — 4.0 mW against 0.98 mW.

Side by side

The numbers that decide it

Specification	Astrolith	Holocene
Impedance	8.2 Ω	9 Ω
Sensitivity	100.1 dB/mW	94.0 dB
Sensitivity (voltage)	121.0 dB/V	114.5 dB/V
Power for 100 dB	0.98 mW	4.0 mW
Voltage for 100 dB	90 mV	0.19 V
Current for 100 dB	10.9 mA	21.0 mA
Highest source impedance that leaves them alone (one-eighth rule)	1.02 Ω	1.12 Ω
Sources that reach 100 dB out of 280	280	279

One caution before reading the rows. For Campfire Audio Holocene the maker publishes no sensitivity figure at all. The number in the table was collected when this database was first built and has never been traced to a manufacturer document, so treat every row below it as an estimate rather than a specification.

What separates them

Where the two part company

1 of the 280 sources has the power for the Astrolith but not for the Holocene — Steinberg UR22C.

1 source is low enough in output impedance for the Holocene under the one-eighth rule but not for the Astrolith (Astell&Kern SR35).

279 of the 280 sources here reach 100 dB on both.

At the level you actually listen at

What each one needs from 80 to 105 dB

The Holocene is more demanding than 56% of the 567 non-electrostatic models in this database; the Astrolith than 28%.

dB SPL	Astrolith power	Astrolith voltage	Holocene power	Holocene voltage
80	9.8 µW	9 mV	0.04 mW	19 mV
85	0.03 mW	16 mV	0.13 mW	34 mV
90	0.10 mW	28 mV	0.40 mW	60 mV
95	0.31 mW	50 mV	1.3 mW	0.11 V
100	0.98 mW	90 mV	4.0 mW	0.19 V
105	3.1 mW	0.16 V	13 mW	0.34 V

What drives both

The cheapest source that satisfies both

Source	Price	Headroom, Astrolith	Headroom, Holocene	Output impedance	Noise
JadeAudio JA11	$20	9.0 dB	3.3 dB	0.5 Ω	1.7 µV
FiiO KA11	$29	21.1 dB	15.4 dB	0.7 Ω	1.7 µV
FiiO BTR11	$36	13.7 dB	8.0 dB	0.5 Ω	8.0 µV

Of the 280 sources here, 279 reach 100 dB on both. 62 of them also publish an output impedance low enough for both under the one-eighth rule and a noise figure that stays below the audible-hiss threshold with both.

The cheapest of the 62 is the JadeAudio JA11, at $20. It leaves 9.0 dB of headroom on the Astrolith and 3.3 dB on the Holocene, its output impedance is 0.5 Ω against a one-eighth limit of 1.02 Ω and 1.12 Ω, and its noise figure puts the hiss floor 14 dB and 21 dB below the 20 dB SPL this site treats as the point where a quiet room stops hiding it.

Try any other source.

Both pages in full

Both have a page of their own. In full: Campfire Audio Astrolith and Campfire Audio Holocene. Each figure on this page is labelled on those pages with where it came from, including the ones Campfire Audio never published — what that maker publishes, counted.