Popular setups and their compatibility
Pick a ready-made setup to get gain staging, impedance safety and cabling worked out instantly.
Shure SM7B on a Scarlett Solo 4th Gen: is a Cloudlifter still needed?
The 4th generation preamp reaches +69 dB where the 3rd stopped at +56. The calculator below shows the gain the SM7B actually asks for at speaking level, and how much of it this interface has left.
Shure SM7B with a Scarlett Solo 3rd Gen and a Cloudlifter CL-1
The classic pairing that made the Cloudlifter famous: a +56 dB preamp against a microphone that wants more. See where the deficit lands with and without the inline preamp.
Topology Myth: Can You Connect a Blue Yeti USB Mic to a Focusrite Scarlett Interface?
Architectural breakdown explaining why USB-only ADC microphones cannot be plugged into XLR analog interface preamps.
Rode NT1 5th Gen and a Scarlett Solo: phantom power and gain
A condenser this sensitive asks for far less gain than a dynamic — and for +48 V it cannot work without. Both are checked below, along with the headroom left before clipping.
Will a Scarlett Solo drive 250 Ω DT 990 Pro headphones?
The answer forums give is yes or no. The arithmetic gives a third one: 0.2 dB short of a 110 dB peak target, and entirely comfortable at 100 dB.
Klipsch RP-600M II on a Fosi V3: are 45 watts enough?
45 W land 1.9 dB under the 105 dB reference peak, and normal listening takes 0.70 W. The same amplifier on a KEF LS50 Meta manages 93.6 dB — a 9.5 dB gap that no amplifier budget closes.
KEF LS50 Meta at 4 metres: how many watts does the room actually take?
85 dB average at the seat costs 16 W. A 100 dB peak at the same seat costs 506 W. Between those two numbers lies everything people mean by «is 45 watts enough».
Shure SM58 on a PreSonus AudioBox GO: three decibels short at a quiet voice, and three ways to get them back
The chain needs 53 dB and the AudioBox GO has 50, so the calculator asks for a booster. Before you buy one: the deficit is a property of the target level and the distance, not of the microphone — at 88 dB SPL it is exactly zero.
How to Connect Shure SM7B to MacBook via Focusrite Scarlett Solo
Complete gain staging analysis, Cloudlifter inline booster necessity check, and cable requirements for broadcast voice tracking.
Connecting MacBook to Klipsch RP-600M II via Denon AVR-S570BT Receiver
Impedance safety validation, continuous peak SPL calculation at 2.5m, and 14AWG banana plug wiring topology.
Thermal Safety Matrix: Can Denon AVR-S570BT Drive 4-Ohm KEF LS50 Meta Speakers?
Thermal risk alert showing why minimum impedance ratings matter for low-sensitivity high-dip audiophile monitors.
Sennheiser HD 600 on a MOTU M2 headphone output
MOTU publishes +12.5 dBu for this output and markets it as rivalling dedicated headphone amps. Against 300 Ω at a 110 dB target the numbers say otherwise — see for yourself.
KEF LS50 Meta on a Yamaha RX-V4A: safe at the impedance dip?
The nominal 8 Ω rating looks compatible with almost any receiver. The real curve dips to 3.2 Ω, and that is the number the amplifier actually meets on bass peaks.
Klipsch RP-600M II with a Denon AVR-S570BT: enough power?
High-sensitivity speakers change the question: it is no longer whether the receiver is loud enough, but whether its noise floor stays out of the way. Level and cable loss are calculated below.
ADAM T7V on MOTU M2 line outputs, not on amplifier speaker terminals
An active monitor carries its own power amps. Its XLR input is a 10 kΩ line load, while the Fosi TB10D is built for 2–8 Ω — so the calculator answers with a topology verdict and a cable, not with a level.
Can a Blue Yeti be plugged into an audio interface?
The microphone already contains its own converter and preamp. What an interface would add, what it cannot add, and which port the signal should actually take.
Electro-Voice RE20 through a Warm Audio WA73 preamp
An outboard preamp changes where the gain comes from — and where the interface knob should sit. The calculation shows the split and the input the signal must land on.
Shure SM7B on a Universal Audio Volt 276: is 55 dB of gain enough?
The Volt stops at +55 dB. Speech at a hand's distance asks this microphone for 60. Five decibels short — and the built-in 1176-style compressor is not the thing that closes the gap.
Shure SM7B and a MOTU M2: how much gain does the M2 actually have?
MOTU publishes an EIN of −129 dBu for this preamp and no gain range at all. Speech asks the SM7B for 58 dB. This page says what can honestly be concluded from that, and what cannot.
SM7B through a dbx 286s into a Scarlett Solo: which input does the 286s go to?
Into the 1/4" jack with LINE selected, never the XLR — and the Scarlett's own gain goes to zero. The 286s supplies up to 60 dB where the microphone asks for 57, so the interface preamp has no job left.
Can a Shure SM7B plug straight into a PC?
No, and not because of gain. The SM7B has no converter inside it, so there is nothing on its XLR pins a USB port or a pink 3.5 mm jack could read. What the adapter cables really are is explained below.
Shure MV7 on a Scarlett Solo 3rd Gen over XLR: does it need a booster?
No — 53 dB required against 56 available, three decibels in hand. Four decibels of sensitivity are the whole difference between this microphone and the SM7B that famously does not fit on this card.
Rode NT1 5th Gen over USB: can it really not clip?
The file cannot clip. The microphone still can. 32-bit float describes what happens after the converter — the capsule and its impedance converter reach their limit before the numbers do.
Cloudlifter CL-1 with a Rode NT1: why the microphone goes silent
The CL-1 eats the +48 V to run its own gain stage and passes none of it on. A condenser behind it receives no power at all — and it did not need the boost either: 35 dB against a card that offers 69.
Electro-Voice RE20 on a Scarlett Solo 4th Gen: is a booster needed?
No — 60 dB required against 69 available, nine decibels in reserve. And the RE20 has a way of finding extra level that no inline preamp can offer: it lets you work close.
Blue Yeti on a USB-C iPad: does it just work?
Electrically yes: the iPad's port supplies 7.5 W and the microphone is class-compliant. What no app can change is the converter inside it — 16 bit, 48 kHz, and that decides how you should set the gain.
Do you need a Radial J48 to record guitar into a Scarlett Solo?
If the guitar is on your desk, no: the Solo's instrument input already does the impedance conversion the DI exists for. And an active DI hands the preamp a signal 6 dB quieter than the cable did.
Synth into a Scarlett Solo: mic input, line input, or a DI box?
Line input. A +4 dBu source is about 13 dB too hot for the mic path at a −18 dBFS target, and a mic preamp's minimum gain is not negative — turning the knob down cannot fix it.
Can you record a microphone into a Schiit Modi+?
No. A DAC is a one-way street: this one lists zero analogue inputs, 0 dB of gain and no phantom power. Its USB, optical and coax sockets are digital sources feeding it, not places to record into.
MOTU M2 with 250 Ω DT 990 Pro: enough, but how much is left over?
The M2 puts out 3.27 V; the DT 990 needs 2.51 V for a 110 dB peak. That leaves 2.3 dB — enough to listen, not enough to stop thinking about the volume knob on quiet recordings.
Sennheiser HD 600 on a Scarlett Solo 4th Gen: loud enough?
The Solo reaches 2.45 V, the HD 600 asks for 4.47 V at a 110 dB peak. It stops 5.2 dB short — and swapping the interface for a louder one does not close the gap.
KEF LS50 Meta on a 109-dollar Fosi V3: safe where a 399-dollar receiver is not
The Fosi is rated down to 2 Ω, so the LS50's 3.2 Ω dip stays inside its limits. The price is level: 45 W into an 85 dB speaker gives 93.6 dB at 2.5 m.
Speaker cable for the LS50 Meta: does 20 AWG instead of 12 AWG change anything?
Over a 4.6 m run, thin cable costs 0.32 dB against the nominal 8 Ω — and 0.79 dB at the 3.2 Ω dip. The loss is not flat, which is the part cable arguments always miss.
Windows PC into a Fosi V3: is an external DAC worth it?
Bus power is not the obstacle — 2.5 W asked against 4.5 W available. The speaker decides the answer: a 94.5 dB horn reproduces the same hiss 9.5 dB louder than an 85 dB monitor.
Two pairs of speakers on one amplifier: what the parallel load really does
Two 8 Ω pairs in parallel are 4 Ω on paper and 2.2 Ω at the dip. The Fosi V3 is rated for that; a receiver rated 6 Ω is out of spec by nearly a factor of three.
Yamaha RX-V4A: should the 4 Ω setting be switched on for Klipsch RP-600M II?
No. The speakers never fall below 4.4 Ω and the receiver is rated to 4 Ω. Switching it on «to be safe» trades away the 0.6 dB of headroom you have over reference level.
Will a more powerful amplifier damage the Klipsch RP-600M II?
No — 80 W sits inside the speaker's 25–100 W window, and at 3 m that is 104 dB at the seat. The amplifier that actually kills tweeters is the small one driven into clipping.
Klipsch RP-600M II at 5 metres: is an 80 W receiver enough for a living room?
99.6 dB at the seat — comfortable for music, 5.4 dB short of the 105 dB film reference. Reaching reference at 5 m would take 281 W per channel, which nothing in this class has.
KRK Rokit 5 G4 from an iPad Pro: will the USB-C port feed the Volt 276?
The iPad Pro 11 (M5) port is rated 15 W and the Volt 276 draws 5.0 W at most — 10 W of margin. The ports that fall short are the 4.5 W phone ports, and they fail as dropouts, not as silence.
DT 770 Pro on a MOTU M2: 32, 80 or 250 Ω — which version should you buy?
All three versions ask for exactly the same 25.12 mW. The 32 Ω needs 0.90 V and keeps 11.2 dB spare, the 80 Ω needs 1.42 V and keeps 7.3 dB, the 250 Ω needs 2.51 V and keeps 2.3 dB. Same driver, three different answers.
ATH-R70x, 470 Ω: the $76 dongle against the desktop DAC, and why 16 dB decides it
The R70x needs 2.73 V — more than a 250 Ω DT 770 and more than an HD 650. A FiiO KA13 on phone power delivers 1.22 V and lands 7 dB short; a Topping DX3 Pro+ delivers 7.6 V and finishes 8.9 dB above target.
Sony MDR-7506: the same 16 dB between dongle and desktop DAC, and it changes nothing
The 7506 needs 0.40 V and 2.51 mW for a 110 dB peak. The lowest-output dongle in the catalogue finishes 9.5 dB above target, the most powerful desktop DAC 25.6 dB. Both answers are «yes», and one of them costs $76.
HD 650 vs HD 660S2 on a Volt 1: both 300 Ω, and the newer one is the easier load
Same impedance, different requirement: the HD 650 needs 2.24 V, the HD 660S2 needs 2.00 V. On the Volt 1's 2.68 V that is 1.6 dB and 2.6 dB of headroom — two «yes, but» answers, not one «yes».
55 Ω and 300 Ω that need exactly the same voltage: K240 Studio vs HD 660S2
Both are rated 104 dB/V, so both need 1.995 V for a 110 dB peak — a $69 semi-open and a $480 flagship, five times apart in impedance. What differs is current: 36.28 mA against 6.65 mA.
iPhone 16 and AKG K371: the cheapest USB-C dongle is already 5.3 dB more than enough
The K371 needs 0.63 V for a 110 dB peak. A $76 FiiO KA13 on phone power delivers 1.158 V into 32 Ω — 115.3 dB, 5.3 dB of headroom. The real constraint here is not the amplifier but the phone's power contract.
HD 650 from a Galaxy S25: every 2 V dongle lands one decibel short
The HD 650 needs 2.24 V. A FiiO KA17 gives 1.993 V and reaches 109.0 dB against a 110 dB peak target; the cheaper KA13 stops at 104.7 dB. The only source here that clears it is a battery-powered DAC at 5.2 V.
AKG K712 Pro on a Scarlett Solo: 62 Ω that asks for more than a 250 Ω headphone
105 dB/V at 62 Ω means 1.78 V and 51 mW for a 110 dB peak — twice the power of a 250 Ω DT 770. The Solo's 2.45 V gets there with 2.8 dB to spare: enough, without headroom.
Sony MDR-MV1 on an EVO 4: loud enough and still the wrong output
24 Ω headphones on a published output impedance of up to 50 Ω: the level still lands 4.3 dB above target, but the ratio is 0.5 where the rule asks for 8. This is the failure that «is it loud enough» never catches.
DT 900 Pro X vs DT 700 Pro X: identical numbers, so the calculator cannot help you
Both are 48 Ω at 100 dB/mW, both need 0.69 V and 10 mW, both reach 117.4 dB on the weakest interface in this catalogue. Open or closed is an acoustic choice, not an electrical one.
250 Ω DT 770 from an iPad Air: the interface that can drive them needs the whole power budget
The 250 Ω DT 770 needs 2.51 V. The iD4 MkII delivers 5.46 V — 6.8 dB of headroom — and asks for 0.9 A at 5 V, exactly the iPad Air's allowance without a Power Delivery contract.
HD 560S on a Pixel 10: the spec sheet answers this one without arithmetic
Sennheiser rates the HD 560S at 110 dB for 1 Vrms, so a 110 dB peak needs exactly 1.000 V. A $76 KA13 delivers 1.203 V into 120 Ω: 111.6 dB, 1.6 dB of headroom — enough, with nothing to spare.
Cambridge AXA35 allows 8 ohms only — and the KEF Q150 dips to 3.7
The manual allows one impedance and no others. The Q150 is 8 Ω nominal but drops to 3.7 Ω, so the verdict is a thermal overload hazard; 35 W give 93.5 dB at 2.5 m.
Q Acoustics 3020i on a Cambridge AXA35: 6 ohms against an 8-ohm-only amplifier
Here the nominal figure already fails: 6 Ω against a required 8 Ω, with a 4 Ω minimum underneath. The calculator uses 86.75 dB per watt, not the printed 88, and returns 94.2 dB at 2.5 m.
Polk Reserve R100 on a Denon AVR-X1800H: 8 ohms on the box, 3.6 in the bass
The receiver is rated down to 4 Ω and the speaker dips to 3.6 Ω. The ratio is 0.90 — inside the rating’s own margin, so the pair plays normally: 80 W give 95.5 dB at 3 m. What it does not have is reserve at the top of the dial.
90 dB/W/m against 88 dB at 2.83 V: the gap is 3.2 dB, not 2
Triangle is the only speaker here quoted in real watts. On one Yamaha A-S301 at 3 m the BR03 reaches 98.2 dB and the 6 Ω Q Acoustics 3030i 95.0 dB — the printed numbers differ by 2 dB.
DALI Oberon 1 with a Marantz Cinema 70s: the green verdict rests on a number DALI never published
DALI publishes 6 Ω nominal and no minimum at all. The calculation substitutes 4.8 Ω — 80 % of nominal — and only then says safe. Level: 50 W and 84.75 dB per watt give 93.8 dB at 2.5 m.
JBL Stage A130 on a Yamaha R-N800A: which impedance setting, and why the menu hides it
A 6 Ω speaker belongs on the 4 ohm MIN setting, which lives in Advanced Setup and not on a rear switch. 100 W and 84.75 dB per watt give 95.2 dB at 3 m; JBL publishes no impedance minimum at all.
Are 40 watts enough? NAD C 316BEE V2 with the ELAC Debut 2.0 B6.2
NAD rates the same 40 W into 8 and into 4 Ω, which is the honest way to say it. With 85.75 dB per watt at 2.5 m that is 93.8 dB — and the 100 W receiver next to it is closer than the sheets suggest.
Denon AVR-S770H: 75 watts or 110? Both, and the difference is 1.6 dB
The box says 110 W at 6 Ω, 1 kHz, 0.7 % THD; the manual says 75 W at 8 Ω, 20 Hz–20 kHz, 0.08 %. Same amplifier. With the Bronze 50 at 3.5 m that is 93.9 dB against 95.5 dB.
B&W 606 S3 on an Onkyo TX-NR6100: 100 watts do not cancel a 3.7-ohm dip
The receiver is rated to 4 Ω and the speaker dips to 3.7 Ω: a ratio of 0.925, marginal rather than hazardous. The level is fine — 96.0 dB at 4 m. Why an impedance rating is about the nominal figure, not the worst point of the curve.
160 W into a 75 W speaker: Emotiva BasX A2+ with Q Acoustics 3030i
Impedance-safe, but the power match flags an overpower hazard: 160 W against a 25–75 W window. 100.8 dB at 2.5 m, and the risk is the volume knob, not the amplifier.
«8 ohm compatible» is not «8 ohms»: Wharfedale Diamond 12.1 on a Marantz PM6007
Wharfedale claims no nominal impedance at all, only a 4.0 Ω minimum. That lands exactly on the Marantz’s 4 Ω limit: safe, with nothing to spare. 45 W give 98.5 dB at 2 m.
ADAM T5V from an iPad Pro M5: why this page shows no amplifier verdict
An active monitor has no impedance, no dB/W/m sensitivity and no speaker cable, so the amplifier calculation has nothing to work on. What decides this chain is line level, not watts.
Neumann TLM 103 through a Cloudlifter CL-2: why the condenser stays silent with +48 V switched on
The +48 V light is on, the cables are right, and nothing comes through. A Cloudlifter eats phantom power and passes none of it forward — so the microphone in front of it is unpowered no matter what the interface does.
Triton FetHead Phantom with a Neumann TLM 103: the one inline booster a condenser survives
Same microphone, same interface, different booster — and this time the chain works. The FetHead Phantom passes phantom power through to the microphone, and pays for it with 18 dB of gain instead of 27.
FetHead or FetHead Phantom for a Rode Procaster? 27 dB against 18 dB, and why it changes nothing here
The Procaster needs 55 dB and the Studio 24c stops at 50 — a five-decibel shortfall a booster closes. Both FetHeads close it. The nine decibels between them buy something the Procaster will never use.
Does every dynamic microphone need a booster? MD 421-II, RE320, SM58 and PodMic on one Audient iD4 mkII
"Dynamic microphones always need more gain" is a sentence about one microphone that escaped into a whole category. On a 58 dB preamp the spread across this shelf is six decibels, and the MD 421-II is louder than an SM58.
Rode PodMic without a Cloudlifter: the Scarlett 4i4 4th gen says yes, the Studio 24c says no — same microphone
The PodMic is the lowest-output dynamic in this catalogue at −57 dBV/Pa. On a 69 dB preamp it needs no help at all; on a 50 dB preamp it is six decibels short. The answer to "do I need a booster" was never a property of the microphone.
AT2020 or AT2035 on bus power? One accepts 11–52 V, the other only 48 V — and the difference is silent
A bus-powered interface generating phantom power from 5 V USB does not always reach a full 48. The AT2035's datasheet accepts anything from 11 V. The AT2020's asks for 48 and says nothing about what happens below it.
Samson Q9U: two "Max Sensitivity" lines, −57 dBV/Pa and −16 dBFS/Pa — which one is the microphone?
Samson's specification sheet puts two identically named rows one under the other. They are in different units, against different references, and one of them already contains a preamp and a converter. Only one belongs in a gain calculation.
Samson Q2U straight into an iPad Air M3: what you give up compared with the Q9U, and it is not output level
The cheaper hybrid is the louder microphone: −54 dBV/Pa against the Q9U's −57. What the extra money buys is the converter — 16-bit at 48 kHz versus 24-bit at 96 — and that is the specification worth arguing about.
Rode NTK on an RME Babyface Pro FS: a condenser that needs no phantom power — and why the button should stay off
Our catalogue records the NTK as "phantom power required: false", which is true and misleading in the same breath. It is a valve microphone with its own mains supply, connected by a 7-pin cable, and the +48 V switch has nothing to do with it.
Shure SM57 through a Golden Age Pre-73 MkIV: which input on the MiniFuse 2, and what to do with the second gain knob
An 80 dB outboard preamp in front of a 56 dB interface is not 136 dB of gain — it is one preamp doing the work and one staying out of the way. The connection goes to the line input, and the SM57 needs 54 dB of the 80.
Lewitt LCT 440 PURE on a Focusrite Vocaster One: 70 dB of gain for a microphone that asks for 32
The Vocaster has the highest maximum gain in this catalogue, built for the low-output dynamics podcasters are told to buy. Put a large-diaphragm condenser on it and you use less than half the knob — which is a good outcome for the wrong reason.
Electro-Voice RE320 with an sE DM1 Dynamite on a MOTU M4: 51 dB needed, 60 available — so why add 28 more?
The RE320 is bought as an SM7B alternative and inherits the SM7B's accessory list along with the reputation. At −52 dBV/Pa it is 7 dB louder than an SM7B and does not need the booster it is usually sold with.
DT 770 Pro 32, 80 or 250 Ω on a Focusrite Vocaster Two: the version decides here
1.64 V from the Vocaster Two gives the 32 Ω version 5.2 dB of spare headroom, the 80 Ω version 1.3 dB, and leaves the 250 Ω version 3.7 dB short of the 110 dB peak target. Same driver, same 25.12 mW, three different answers.
DT 770 Pro on a FiiO K11: the impedance version that stops mattering
4.24 V and an output impedance under 1.2 Ω put all three DT 770 versions at +13.2, +9.4 and +4.5 dB of headroom, with damping ratios of 26.7, 66.7 and 208. On a $130 desktop unit the version question becomes a question about earpads.
Does the ATH-M50x need a headphone amp? Universal Audio Volt 2, in numbers
The M50x needs 0.692 V and 12.59 mW for a 110 dB peak. The Volt 2 delivers 2.68 V, which is 121.8 dB — 11.8 dB more than the target. The weakest headphone output in this batch still leaves 7.5 dB. The answer is no, and here is the arithmetic.
iPhone 16 + Truthear SHIO + ATH-M50x: low gain is already enough
The SHIO's high gain gives 2 V and puts the M50x at 119.2 dB, 9.2 dB over target. Low gain gives 1.4 V and still reaches 116.1 dB, 6.1 dB over. The gain switch buys 3.1 dB of ceiling you do not need — and lifts the noise floor with it.
Grado SR80 on a DragonFly Cobalt: the only spec sheet that writes the scale into the line
Grado prints "SPL 1mW: 98" — the scale is in the line itself. That makes the SR80 112.20 dB/V, needing 0.776 V, and the Cobalt's 2.1 V reaches 118.6 dB. Read the same 98 as dB/V and the identical chain comes out 5.6 dB short.
DT 770 Pro 32 Ω on an Audient EVO 8: the 1/8 rule, finally with numbers on both sides
Audient publishes <50 Ω of output impedance. Against a 32 Ω headphone that is a ratio of 0.6 where the rule wants 8, and the divider costs 8.1 dB of level. No DT 770 version comes out clean here: 32 Ω and 80 Ω flag damping, 250 Ω runs 1.7 dB short.
HD 660S2 is 300 Ω, not 150: every amp recommendation written before 2022 is about a different headphone
104 dB/V at 300 Ω means 1.995 V, 6.65 mA and 13.27 mW for a 110 dB peak. The Volt 476 delivers 2.68 V, reaching 112.6 dB — enough, with 2.6 dB spare and nothing to waste. The current is trivial; the voltage is the whole problem.
HD 660S2 on a Qudelix 5K: exactly 0.0 dB of headroom, which is not the same as enough
The 5K's published 2 Vrms on the 3.5 mm port puts the 300 Ω HD 660S2 at exactly 110.0 dB against a 110 dB target. It reaches the peak with the volume at maximum and nothing left over — the clearest possible picture of what "it plays" leaves out.
Pixel 10 + Hidizs S9 Pro Plus + DT 700 Pro X: one impedance instead of three
48 Ω at a stated 100 dB SPL (1 mW / 500 Hz) works out to 113.19 dB/V and needs 0.693 V. The dongle's 2.1 V reaches 119.6 dB — 9.6 dB of headroom from a phone. The unit in beyerdynamic's own line is what makes the number readable.
ATH-M40x vs ATH-M50x on an SSL 2+ MkII: 0.6 dB apart, and both far past the target
112.56 vs 113.20 dB/V — the M40x needs 0.745 V, the M50x 0.692 V. The SSL's 3.46 V puts them at 123.1 and 123.8 dB, with damping ratios of 35 and 38 against a published output impedance under 1 Ω. Electrically these are the same purchase.
DT 770 Pro 80 Ω on an iFi hip-dac 3: the folk advice is right, and here is why
3.2 V puts the 80 Ω version at 117.1 dB, +7.1 dB of headroom. On the same device the 32 Ω sits at +11.1 and the 250 Ω at +2.1. "Buy the 80" turns out to be arithmetic rather than folklore — but iFi publishes two voltages, and no output impedance.
Grado SR80 on a Chord Mojo 2: what $650 actually buys when 2.1 V was already enough
The SR80 needs 0.776 V. Mojo 2 publishes 5.2 V at 300 Ω and 4.24 V at 30 Ω — 126.5 or 124.7 dB depending on which point applies. Neither number is the reason to buy it: the 0.06 Ω output impedance gives a damping ratio of 633 where the rule asks for 8.
Audio-Technica AT2035 on an AudioBox GO and an iPad: 11–52 V phantom, and a datasheet that names the wrong microphone
The AT2035 runs on anything from 11 to 52 V; the AT2020 wants 48 V. Audio-Technica's own AT2035 sheet attributes the wide range to the AT2020, and its AT2020 sheet contradicts it. The chain itself needs 32 dB of the AudioBox GO's 50.
Cloudlifter CL-Zi with a Shure Beta 58A: the three-position switch is attenuation, not three levels of gain
Shops describe the CL-Zi's +25 / +12 / +8 dB switch as three gain settings. Cloud calls it an output attenuation switch — the boost is fixed and the switch only takes level away, which changes what the box can and cannot fix.
ART Tube MP Studio V3 with an Elgato Wave DX: ART's own sheet says 50–60 dB, the shops say 70 or 80
ART publishes `Maximum Gain: 50 dB – 60 dB`. Listings advertise 70 dB and even 80 dB “XLR to XLR”. ART's own maximum output level of +14 dBu settles the argument: at speaking level, more than about 73 dB of gain cannot come out of the box.
Focusrite ISA One with a RODE NT1-A: is the maximum gain 60 dB or 80 dB? Focusrite never says
The ISA One publishes `0dB to 60dB in 10dB steps` and, separately, `20 dB of variable gain`. Whether they add to 80 dB or the trim is a vernier inside the steps is never stated. A page about a preamp whose headline number is unknown.
Klark Teknik Mic Booster CT 1 with an SM58: does phantom power reach the microphone? Nobody has published the answer
With a dynamic in front, this chain is fine: 34 dB of the EVO 4's 58 after the booster's +25. With a condenser in front, the answer is unknown — Klark Teknik does not state whether phantom power passes through, and this site will not invent it.
Radial McBoost with a Sennheiser e 835: one of its three load settings is below the microphone's published minimum
The McBoost offers 600 Ω, 2.7 kΩ and 30 kΩ input impedance. Sennheiser specifies a minimum terminating impedance of 1 kΩ for the e 835. One of those three positions is outside the microphone's own specification — and Radial, like two rivals, never says whether phantom power passes on.
Soyuz Launcher with a Shure Beta 57A: 26 dB from a transformer, and the same unwritten phantom question
The Beta 57A needs 52 dB on an iD4 MkII and the interface has 58, so the Launcher is a tone decision rather than a rescue. Soyuz publishes 26 dB and phantom operation, but not whether phantom power reaches the microphone.
Warm Audio WA12 MKII with a Sennheiser MK 4 into an AudioBox GO: 71 dB of gain and 31 dB of use for it
A 449-dollar preamp in front of a 79-dollar interface is not absurd, but the gain knob is the wrong reason for it. The MK 4 asks 31 dB; run the WA12 anywhere near its 71 dB and the AudioBox GO's +10 dBu input disappears 22 dB below the signal.
Aston Origin on an Audient EVO 4 and an iPad mini: a higher clip point costs you gain, it does not save it
The same Aston Origin needs 30 dB on a Volt 176 and 37 dB on an EVO 4. The seven-decibel difference is not the microphone and not the preamp — it is where each converter clips, a number most buyers never look at.
sE Electronics X1 S on a Volt 176: “30 mV / Pa (−31 dBV)” — the two halves of that line disagree by half a decibel
sE prints both units on one line, but 30 mV/Pa is −30.5 dBV, not −31. It is half a decibel and it moves the required gain by a whole one — a small, checkable example of why a converted number should never be quoted as if it were measured.
Elgato Wave DX on an Audient iD14 MkII: an XLR-only microphone with 600 Ω of output impedance and no published load limit
The Wave DX needs 53 dB of the iD14 MkII's 58 — five decibels of margin, and none at all on a 50 dB interface. Elgato publishes a 600 Ω source impedance, four times a Shure dynamic's, but never says what load it needs.
Does the Corsair HS65 Surround need an amp? The spec sheet says 32k Ohms
Corsair prints «Impedance: 32k Ohms @ 1 kHz» and «114dB (+/-3dB)» with no reference unit. Read as printed, a FiiO KA13 falls 9.3 dB short of a 110 dB peak. Read the way the numbers actually mean, the same dongle has 5.3 dB to spare. Both readings, calculated.
Corsair HS55 Stereo impedance: 32 or 32,000 ohms? The same line is on three product pages
«Impedance: 32k Ohms @ 1 kHz» appears verbatim on the HS55 Stereo, the HS55 Surround V2 and the HS65 Surround. On a Truthear SHIO the printed reading gives −5.0 dB, the real one +10.0 dB. Three headsets, one measurement, a 15 dB question.
Razer Kraken (2019) sensitivity: 109 dB per volt or per milliwatt? On a FiiO KA13 it decides everything
Razer prints «Sensitivity (@1 kHz): 109dB» with no reference. Per volt, a FiiO KA13 arrives with 0.3 dB to spare — it plays, with nothing left. Per milliwatt, the same dongle has 15.2 dB. Razer names the unit on its other sheets, and that is how the question is settled.
Razer Kraken Pro V2 impedance and sensitivity: what «118 ± 3 dB» costs on a Tascam US-2x2HR
Razer prints «Sensitivity (@1 kHz): 118 ± 3 dB» with no reference and, one row below, «Input/Output power: 30 mW (Max)». Per volt the Tascam is 4.1 dB short; per milliwatt it has 10.8 dB but fails on output impedance. The neighbouring row is what settles the unit.
Razer Barracuda X vs beyerdynamic at the same 96 dB: «by HATS» means it was measured on a different rig
«Sensitivity: 96dBSPL/mW@1 kHz by HATS» — Razer names its measurement rig, which almost nobody does. On a Qudelix 5K the Barracuda X reaches 117.0 dB SPL, +7.0 dB. The ±3 dB the rig itself is worth moves that to +4.0 or +10.0, and reading the unit wrong costs 15.
Moondrop KATO sensitivity: «123dB/Nrms» is a unit that does not exist. Which one did they mean?
Moondrop prints «Sensitivity: 123dB/Nrms (@1KHz)». There is no unit called Nrms. Read as volts — as every other Moondrop sheet writes it — a FiiO KA17 sits 18.8 dB above a 110 dB peak; read as milliwatts, 33.7 dB. Neither is too quiet, and that is exactly the problem.
Shure Aonic 3 sensitivity: the guide says «108 dB SPL/MW» — MW is the megawatt
Shure's Aonic 3 guide prints «Sensitivity at 1 kHz — 108 dB SPL/MW» in upper case, while the SE215 and SE846 guides on the same server print «dB SPL/mW». On a FiiO KA13 the milliwatt reading gives +15.0 dB, the volt reading −0.8, and the literal megawatt asks for 6419 V.
Does the Shure Aonic 5 need an amp on an Audient EVO 4? The unit is ambiguous, the 50 Ω output is not
«Sensitivity at 1 kHz — 119 dB SPL/MW» is 14.4 dB away from its other reading, and on the EVO 4 the verdict is the same either way: the interface publishes a 50 Ω output against a 36 Ω balanced-armature load. Here the output impedance outranks the unit.
Etymotic ER2XR and ER2SE publish identical numbers. So does the calculator tell them apart?
«Impedance: 15 Ohms @ 1kHz / Sensitivity: 96 dB @ 1kHz, 1mW» appears on both the ER2XR and the ER2SE page. Etymotic labels its scale, so the unit is not in doubt — the model is. On a MiniFuse 1 the answer is +6.4 dB and a damping ratio of 1.5, for both.
Sennheiser IE 200 impedance: 16 or 18 ohms? Sennheiser publishes both, and shows what everyone else hides
«Impedance (without cable / with cable) 16 Ohm / 18 Ohm» — almost nobody separates these. On a Lewitt CONNECT 2 the two numbers differ by 0.1 dB in level and move the damping ratio from 9.5 to 8.4, straddling the 1/8 rule. That is what a single low figure hides.
beyerdynamic MMX 300 PRO and MMX 330 PRO both say 96 dB — closed and open, one number, no unit
«Nominal sound pressure level: 96 dB» with no reference, on a closed 48 Ω headset and on an open one. Per milliwatt a Focusrite Vocaster One arrives with +2.6 dB; per volt it is 10.6 dB short. beyerdynamic names the unit on its PRO X pages, and that is the evidence.
Koss GMR-540-A-ISO and GMR-545-A-AIR publish the same 15–22,000 Hz — closed and open both
Every figure on the closed ISO page matches the open AIR page: 35 Ω, «Sensitivity: 103 dB SPL» with no unit, 15–22,000 Hz. On a PreSonus Studio 24c the milliwatt reading gives +11.7 dB and the volt reading −2.8. Koss writes «/1mW» on its own Porta Pro page.
SM7B with Elgato Wave XLR MK.2: what do the 80 dB of gain actually buy?
The SM7B asks this box for 56 dB and gets 80, so the headline number is not the interesting one. The interesting one is the input ceiling, which Elgato prints as 6 dBV while the rest of the industry prints dBu — and that unit is worth 2.2 dB of required gain on this very page.
Shure SM7B with SSL 2 MkII: are 64 dB of gain enough?
Enough, with 7 dB in hand — which is more margin than a Scarlett 2i2 4th Gen leaves, although the Scarlett has 5 dB more gain on paper. Comparing maximum gain figures without the clipping points that go with them ranks these two interfaces backwards.
Audient iD4 MkII with a Shure SM7B: two decibels short
The chain needs 60 dB and the interface publishes 58. Two decibels is not a booster's worth of shortfall — it is one notch of recording level, or a hand's width of distance, and this page shows exactly which cheaper move erases it.
Shure SM7dB with Focusrite Vocaster One: why does a dynamic microphone need +48 V?
This is the pair Thomann sells as a bundle, and it works — but the SM7dB has three published sensitivities, not one, and which of them applies depends on a switch and on the phantom power button. With +48 V off it is a plain SM7B.
Rode PodMic USB: USB or XLR — which side is louder, and what do we actually know?
One microphone, two chains, two sets of numbers — and only one of them comes from a data sheet. On XLR the PodMic USB asks a Scarlett 2i2 4th Gen for 62 dB; on USB the gain lives inside the microphone and Rode never publishes it, so the site substitutes a figure and says so.
Shure SM58 with Focusrite Scarlett Solo 4th Gen: enough gain for a quiet voice?
Twelve decibels in hand at a normal speaking level and two at a quiet one. The margin on this pair is almost entirely a property of your voice and your distance, not of the interface — ten decibels of speaking level eat ten of the twelve.
Shure SM57 into a Scarlett 2i2 4th Gen: how much gain do you actually need?
Between 31 dB and 71 dB, on the same pair, depending on what you point it at. A snare leaves 38 dB unused; a quiet voice at arm's length is 2 dB out of reach. The gain question has no answer without a source level, and this page gives all three.
Cloudlifter or FetHead for an SM7B: what do the 2 dB change?
On a Scarlett Solo 3rd Gen both boosters solve the problem and the difference between them is two decibels — inaudible as a verdict. What separates them in our data is not gain at all: one manufacturer documents what happens to phantom power, the other does not.
SM7B with a Klark Teknik CT 1 on an Audient EVO 4: does the cheap booster do the job?
Here the booster is genuinely needed — the EVO 4 is 6 dB short of an SM7B on its own — and a $45 box delivers the same published +25 dB as a $129 one. The catch is in the document those decibels come from: one data sheet covers three different boxes.
Shure SM7dB with a Cloudlifter: do you need both?
No — and not because the gain is excessive. The Cloudlifter does not pass phantom power onward, and the SM7dB's built-in preamp runs on phantom power, so putting the two in series switches the microphone's own +28 dB off and sells them back to you for $129.
Does the Electro-Voice RE20 need a Cloudlifter?
On the oldest and cheapest Scarlett, at a hand's distance, no: the RE20 fits inside 56 dB of gain with 2 dB to spare. Move to arm's length and the same chain is 8 dB short. The question is about your distance, not about the microphone.
Does an SM57 need a Cloudlifter on a Scarlett 2i2 4th Gen?
No. The pair already has 8 dB in hand for speech, and adding +25 dB leaves 33 dB of the interface preamp unused — on a loud source it pushes that preamp down to 6 dB of gain, the one place where an inline booster measurably costs you something.
DT 990 Pro 80 ohm or 250 ohm on a Scarlett 2i2 4th Gen: which is actually louder?
Two versions of one headphone on the best-selling interface, and the answer is not the one the impedance suggests. The 80 ohm version reaches 110.5 dB, the 250 ohm one 108.2 — and both sit under the 8x output-impedance rule. The whole comparison rests on a sensitivity figure beyerdynamic prints once, for both versions, without ever naming the unit.
Fostex T50RP mk3 on a Scarlett 2i2 4th Gen: does a planar need its own amp?
The forum rule says a planar needs an amplifier, and here it lands on the right answer for the wrong reason. The pair falls 3.2 dB short of the peak target, but not because of impedance: the interface's own 50 ohm output resistor throws away exactly half the voltage into this 50 ohm load, and what runs out is 63 mW.
Sennheiser HD 490 PRO on a Scarlett 2i2 4th Gen without an amp: exactly enough
110.0 dB against a 110 dB target: enough with nothing to spare. The part that actually moves is the tonal balance — 130 ohms against a 50 ohm output is a ratio of 2.6 where the rule wants 8. And the 300 mW on Sennheiser's spec sheet is not a request for a 300 mW amplifier; this chain needs 24 mW.
Focusrite Vocaster Two with Superlux HD-681: the cheap headphones are the loud ones
This is a shop bundle, and it computes better than the obvious studio pairing. 32 ohms and 98 dB/mW give 117.2 dB on an interface that manages only 106.3 dB with a 250 ohm DT 990 — 10.9 dB in favour of the cheaper half. The number rests entirely on the voltage side of Focusrite's sheet.
Moondrop Dawn Pro with Sennheiser HD 600: two volts is 7 dB short
The named dongle pairing, and on the 3.5 mm socket the answer is no: 103.0 dB against a 110 dB target. The same dongle with an HD 650 reaches 109.0 — two Sennheisers of identical impedance, six decibels apart. And the fix on this page is a cable, not an amplifier.
Qudelix 5K with Sennheiser HD 650: enough, with nothing to spare
109.0 dB against a 110 dB target — the verdict that sits between comfortable and too quiet, and the whole distinction is 0.24 V. The load asks for 7.5 mA, which any phone can source. What a 300 ohm headphone runs a battery source out of is volts, not current.
WiiM Amp with KEF LS50 Meta: does 2.67 ohms cover the 3.5 ohm dip?
The most-searched amplifier pairing for these speakers, and the first amplifier in this catalogue whose published minimum clears the LS50 Meta's dip. It passes — but the whole verdict rests on which half of one WiiM spec row you believe, because the row names two different lowest loads.
WiiM Amp Pro with DALI Oberon 1: what does the Pro actually buy?
94.6 dB at two and a half metres from the smallest bookshelf in the Oberon line. The interesting part is that every number on this page is also the plain WiiM Amp's: the manufacturer's own comparison sheet prints identical power and identical minimum impedance for both models.
WiiM Amp Ultra with Q Acoustics 3030i: 100 watts into a 75 watt speaker
The loudest bookshelf pairing in this batch — 98.8 dB at two and a half metres, and the only one that clears the reference at a metre. The amplifier also out-rates the speaker by a third, and our page stays silent about it. This one explains why, because the threshold that keeps it silent is our judgement, not anyone's datasheet.
Marantz PM6007 with DALI Oberon 5: are 45 watts enough for a floorstander?
The first suggestion German search makes on this amplifier, and the answer is 93.7 dB at three metres — enough for the room, 11.3 dB under cinema reference. The pearl is that the Denon PMA-600NE everyone compares it with computes to the same number, to the decimal.
Denon PMA-600NE with DALI Oberon 3: what does «Maximum SPL 108 dB» actually mean?
A German named pairing: 94.3 dB at two and a half metres, comfortably enough for the room. But DALI's own «Maximum SPL 108 dB» is worth chasing, because reaching it would take 168 W — more than DALI's own recommended maximum for the same speaker.
Denon PMA-600NE with DALI Oberon 1: 86 dB per 2.83 V is not 86 dB per watt
The German named pairing for the smallest bookshelf in the Oberon line: 93.3 dB at two and a half metres. The pearl is arithmetic — reading the sensitivity in the wrong base is worth exactly as much as fifteen extra watts, and for a reason that is not a coincidence.
Shure SM7B + Scarlett 2i2 4th Gen: is 69 dB of gain enough?
The forum answer is «the SM7B needs about 60 dB». That number does not exist on its own. On this card the same microphone asks for 64 dB, on a Scarlett Solo 3rd Gen for 57, on a PreSonus AudioBox USB 96 for 45 — because the required gain is set by the card's clipping point, not by the microphone.
SM7B + Cloudlifter + Scarlett 2i2: 30 dB of gain you will never use
The Cloudlifter is the standard answer to the SM7B, and on a Scarlett Solo 3rd Gen it is the right one. On a 2i2 4th Gen the card already has 5 dB in hand; adding +25 dB leaves 30 dB that never reaches the gain knob. Both chains, calculated, plus the one case where the booster does earn its place on this card.
Shure SM7B on a PreSonus AudioBox USB 96: is the built-in preamp enough?
No — but the shortfall is 10 dB, not the 25 dB that «35 against 60» suggests, because this card clips at −3 dBu and therefore needs less gain than a Focusrite. Both readings calculated, with the sentence on PreSonus's own page that starts the confusion.
Rode PodMic on a Scarlett Solo 3rd Gen is quiet: how quiet, in decibels
At a normal speaking level this pair has exactly 1 dB in hand — it works, with nothing spare. Five decibels of quieter voice, or twice the distance to the capsule, and the same chain is 4 to 9 dB short. The margin is not a property of the gear; it is a property of how you speak into it.
Shure SM7dB + Scarlett 2i2 4th Gen: which gain switch position?
Shure publishes three sensitivities for one microphone: −59, −41 and −31 dBV. On a 2i2 4th Gen that is 5, 23 and 33 dB of spare gain — and the two loud positions exist only while phantom power is on, which makes this the dynamic microphone that stops working without 48 V.
Focusrite Scarlett 2i2 4th Gen with Beyerdynamic DT 770 Pro 80 Ohm
The best-selling interface meets the best-selling studio headphone, and the answer is two answers. Level: 110.5 dB, half a decibel over target. Tone: the card's 50 ohm output against 80 ohms is a ratio of 1.6 where 8 is wanted. And the 250 ohm version of the same headphone is the one that comes up short.
FiiO K11 with the Sennheiser HD 600 — and why the HD 650 is a different question
Same 300 ohms, same family, 6 dB apart — and the K11 is exactly the source where those 6 dB flip the verdict. HD 650: 115.5 dB, comfortable. HD 600: 109.5 dB, target reached with nothing to spare. The catch is that the deficit is in volts, and the K11's headline 520 mW says nothing about volts.
FiiO K11 with the Sennheiser HD 560S: the problem is too much, not too little
12.5 dB above what a 110 dB peak needs, which is a factor of 4.2 in voltage: the whole listening range lives in the first quarter of the volume knob. On the same DAC the HD 600 sits at −0.5 dB. Thirteen decibels apart, and only one of the two questions ever gets asked.
Truthear HEXA on a Focusrite Scarlett 2i2: do you need a separate DAC?
Yes — but not because the interface is too weak. It is 7.1 dB too strong. The reason is 50 ohms of output resistance against a 20.5 ohm in-ear: a ratio of 0.4 where 8 is wanted, the worst in the whole catalogue. A 25-euro dongle does what the 200-euro interface cannot.
Cambridge Audio CXA81 with KEF LS50 Meta: 80 watts and a 3.5 ohm dip
The named pairing of the section, and the answer is «play them, just not flat out». 85 dB per watt is the lowest sensitivity in the catalogue: 80 W give 104 dB at one metre and 94.5 dB at three. The impedance dips to 3.5 ohms against an amplifier rated to 4 — 12.5 % under, which our calculator reads as marginal rather than hazardous. The 3.2 ohms repeated all over the web belong to the LS50 this model replaced.
Denon PMA-600NE with DALI Spektor 2: how loud do 45 watts actually get?
The cheapest bookshelf in the catalogue turns out to be the hardest to drive: 84.5 dB printed at 2.83 V becomes 83.25 dB per watt on a 6 ohm load — lower than a KEF LS50 Meta. 45 W give 99.8 dB at one metre and 91.8 dB at 2.5. Loud enough for the room, and a warning about the scale the number is printed in.
Marantz PM6007 with DALI Oberon 7: are 45 watts enough for a floorstander?
45 W and 87.25 dB per watt give 103.8 dB at one metre and 94.2 dB at three — enough, without reserve. The surprise is the size of the upgrade: the entire Oberon range on this amplifier spans 2.5 dB, and doubling the amplifier's power is worth less than moving your chair one metre closer.