DBX 286S Microphone Preamp

Specifications

Product features

19-inch rack size: 1U
Number of channels: 1
Digital output: No
Sustainable product: Not specified
Energy source: AC
Phantom power: Yes
Phase reverse: No
Headphone output: No
Built-in compressor: Yes
Built-in equaliser: No
Built-in limiter: No
Connection sockets: 2x TRS send/return (balanced)
Stereo function: No
Analogue audio input type: Microphone input (XLR)
Analogue audio output type: Unbalanced line out (TS jack)
Type of dynamic processor: Compressor, expander, gate, de-esser
Equipped with tube: No

Weight and dimensions including packaging

Weight: 3,0 kg
Dimensions: 56,5 x 29,0 x 6,5 cm

Product specifications

studio-grade mic preamp / channel strip processor
classic DBX compression puts great sound within reach
frequency-tuneable de-esser reduces sibilance and high-frequency distortion
enhancer increases the detail and definition of the high and low frequencies
programme adaptive expander/gate
insert jack for adding an external processor
full range of meters and status LEDs
+48V phantom power
precision dented controls
microphone input, type: floating balanced, pin 2 hot
microphone input, impedance: ~4.2 kOhms
microphone input, max. level: 0.25 Vrms, gain: 30 dB
microphone input, gain adjustment range: 0 dB to +60 dB
microphone input, phantom power: 48 VDC, applied to XLR pins 2 and 3 through 6.81 kOhms resistors
microphone input, CMRR: > 40 dB, typically 55 dB
microphone input, EIN: -125 dBu, 22 Hz - 22 kHz, 150 ohms source impedance
line input, type: floating balanced, tip hot
line input, impedance: 10 kOhms unbalanced, 20 kOhms balanced
line input, max. level: > +21 dBu, balanced or unbalanced
line input, gain adjustment range: -15 dB to +45 dB
line input CMRR: > 40 dB, typically 55 dB
insert, type: 6.3mm TRS phono jack, normalised, tip is send, ring is return
insert, ring impedance: > 5 kOhms
insert, ring max. level: > +21 dBu
insert, tip impedance: 100 ohms
insert, tip max. level: > +21 dBu, > +20 dBm (600 ohms load)
insert, noise: < 89 dBu, unweighted (20 Hz - 20 kHz); line gain control set to 0 dB
insert, distortion: < 0,01% THD, 20 Hz - 20 kHz, +10 dBu
line output, type: 6.3mm TRS phono jack; balanced/unbalanced
line output, impedance: 100 ohms unbalanced, 200 ohms balanced
line output, max. level: > +21 dBu, > +20 dBm (600 ohms load)
line output, gain adjustment range: -30 dB to +10 dB
line output: noise < -80 dBu unweighted (20 Hz - 20 kHz); both gain controls set for 0 dB, all processing controls off
line output, frequency response: 20 Hz to 20 kHz, +0.5/-0.5 dB
line output, distortion: < 0,08 THD, 20 Hz - 20 kHz, +10 dBU, all processing controls off
compressor, threshold range: -40 dBu to +20 dBu
compressor, threshold characteristic: OverEasy
compressor ratio > 4:1 for input levels beyond 20 dB above threshold
compressor, max. compression: 30 dB
compressor, attack time: program dependant; > 2 for small level increases down to 10ms for large increases
compressor, release time: program dependant; adjustable between approximately 1 dB/sec and 75 dB/sec
compressor, distortion: typically < 0.05%THD, 20Hz-20kHz, 15dB G/R, +10dBu Output, density @ 0
compressor, SMTPE intermodulation distortion: < 0,05%; 60 Hz - 7 kHz 4:1, 15 dB G/R, +10 dBu output level, density @ 0
de-esser, characteristic: wideband gain reduction
de-esser, frequency range: 800 Hz to 10 kHz high pass, 12 dB/octave
de-esser, release time: program dependent approximately 1 ms/dB
enhancer, HF detail characteristic: program-controlled shelving equalizer, approximately 15 dB maximum HF boost
enhancer, LF detail characteristic: bell-shaped boost @ 80Hz, bell-shaped cut @250Hz, ratio is approximately 2:1
expander/gate, threshold range: off to +15dBu
expander/gate ratio: adjustable 1.5:1 to 10:1
expander/gate, max. depth: > 50 dB
expander/gate, attack time: program-dependant, approximately 2 ms (at maximum attenuation)
expander/gate, release time: program-dependant, approximately 10 ms/dB
expander/gate, typically 105 dB
operating temperature: 0 degrees Celsius to 45 degrees Celsius
power consumption: 15W
operating voltage: DO 120VAC 60Hz, 100VAC 50/60Hz EU 230VAC 50/60Hz
dimensions: 45 x 146 x 485 mm
weight: 2.04 kg

Service promise

Bax Music Warranty This product comes with a 3-year warranty.

This product comes with a 3-year warranty.

Reviews (71)

4.5

71 reviews

Rating

5 stars 47 4 stars 18 3 stars 4 2 stars 2 1 star 0

Write a review

4 / 5

DBX 286S Microphone Preamp

Good unit, actually in stock!
Using it to boost a KU5a into a Focusrite Clarett 4+ PRe, and it works well, especially the noise gate/expander. Needs quite a hot signal to trigger compression, and the controls are a little quirky. The top panel is liable to pick up any vibrations eg from PC cooling fan on top of my rack trolley. But electronically this is quiet and clean, very good value.

Bax online service did a good job in sending on, for free, on request, a UK power cable that was originally missing from a parcel obviously packed for the Netherlands market.

Only real grumble is that this DBX 286s lacks a mains power switch so I need to cut the power to the whole rack, when I'd prefer to charge up the battery on my portable.

July 30, 2024 | Andrew C.

4 / 5

DBX 286S Microphone Preamp

As the others mention, the unit cleans,sparkles and boosts the audio beautifully, its ideal to have inline for improving your sound or using instead of a cloudlifter. Its a low noise high quality device.

I do want to add what it wont do. I needed a unit to really flatten my mic peaks and regulate all spikes and peaks on a live stream. This unit was not correct for that, unless an additional limiter/compressor in a final output stage was used. The DBX left me with too much variation on output level even at its most aggressive setting. Don't let this put you off if you want a unit that provides some audio regulation and a huge dynamic range improvement but it wont squash up your level to a brick wall.... I give it 100% providing you are buying it for the right reason. Peter

October 21, 2017 | Peter N.

5 / 5

DBX 286S Microphone Preamp

What a delightful little product.

Packed with excellent features which boosts/cleans your vocal signal before recording.

But if you know how to set up sends from your DAW, you can use this as an external effect on any channel in your DAW. This allows the flexibility of getting a better quality of recording.

The mic pre-amps on my audio interface are really good but this adds 10/20% better quality which is significant.

And for the price it is a bargain.

April 25, 2017 | Shezada C (O.G.S Productions)

5 / 5

DBX 286S Microphone Preamp

You can't go wrong at this price! Superb bit of kit with so many features on it. Have tried it a few times and gotten used to it now. It did take a while to get the settings to suit my voice.

Robust piece of kit too.

April 14, 2017 | Az

Reviews from other countries

5 / 5

DBX 286S Microphone Preamp

J'en rêvais depuis des années - et cela vallait vraiment la peine de patienter :) La pièce qui manquait encore à mon mini studio pour traiter facilement et efficacement les prises de chant ! Résultat: pistes propres et sons uper net.

Très très satisfait ... et comme d'hab, livraison impeccable

June 18, 2026 | Pierre-Henri

This review was automatically translated from French.

2 / 5

DBX 286S Microphone Preamp

Na een paar jaar valt de DBX zeer regelmatig uit. Als hij werkt is het een top ding maar dit al na een paar jaar is te snel. Het internet staat er vol mee.....

October 23, 2025 | Ane

This review was automatically translated from Dutch.

3 / 5

DBX 286S Microphone Preamp

Onbegrijpelijk dat dit apparaat geen power switch heeft. Apparaat zit in een 19 inch rack, en de het spanningsblok ligt achter in het rack. Kortom een grote tekort koming

August 4, 2025 | Corne

This review was automatically translated from Dutch.

4 / 5

DBX 286S Microphone Preamp

Hele goede microfoonvoorversterker! Hij werd me aangeraden door een vriend, omdat ik last had van pieken en dalen in mijn audio, te veel scherpte... Hij raadde me deze aan en het werkt prima. Mijn audiokwaliteit is niet te vergelijken met ervoor en hij is ook makkelijk in te stellen en te personaliseren voor jouw stem. Voor de prijs, doet ie zeker wat ie beloofd.

September 21, 2024 | Alexandra

This review was automatically translated from Dutch.

5 / 5

DBX 286S Microphone Preamp

Dit is echt een hele goede microfoonvoorversterker. Laatst nog eentje aangeschaft. Wil je je stem professioneler laten klinken dan is dit een absolute aanrader. Een keer instellen en je opnames klinken gelijk goed. De de-esser werkt ook erg goed. Essentieel om te hebben :-)

November 14, 2023 | Charles

This review was automatically translated from Dutch.