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On-Stage HA4000 - 4 Channel Pro Headphone Amplifier

18% off
On-Stage  |  SKU: HA4000

Product Highlights
  • High 200 mW output for loud, clear headphone monitoring
  • Stereo/mono switch for flexible use
  • Auxiliary 3.5 mm input for mixing backing tracks or metronomes
  • Runs on 9V battery (included) or optional DC adapter
  • Simple volume control for intuitive operation
  • Rugged metal chassis with rubber feet for stage reliability

On-Stage - Since 1979

Precision Gear for the Modern Performer since 1979

For over four decades, On-Stage has been the gold standard for musicians and audio professionals who demand gear that is as hardworking as they are. Born in the USA with a commitment to innovation and value, On-Stage has grown into one of the most trusted names in the music industry worldwide.

Click to view the On-Stage Collection HERE>

On-stage products now on sale at Audio Direct
£32.95 £39.99

Expert Advice, Click for Help

Need help? Call us on: 02476 369897

Use Live Chat or e-mail us directly at: sales@audiodirect.co.uk

OPEN: Mon to Fri - 9am to 5pm (Closed Sat/Sun)

We are more than online retailers, our sales staff have a passion for making music and give honest frank feedback on their experience with your chosen product. Call us for a chat or read all about us HERE>

FREE Delivery & Easy Returns Info

DELIVERY

FREE Mainland UK Shipping for orders over £99 (Standard Service 2-3 days)

£3.99 per order for orders below £99. (Standard Service 2-3 days)

FAST Delivery Needed? We got you! find express delivery options at checkout or read our: Comprehensive delivery information HERE>

EASY RETURNS

Not completely happy with your audio gear? No problem! simply return it back to us for a full refund within 60 days of purchase.

Find comprehensive return T/C instructions HERE>

Why buy On-Stage from us?
  • Official On-Stage® UK retailers
  • Est. in 2001, 25 years of 5-star reviews
  • Expert advice, before & after your purchase
  • Manufacturer warranties you can rely on
  • Price match promise, never knowingly beaten on price
  • Confidence at checkout. 100% Secure shopping
  • FREE UK delivery on purchases over £99.00
  • Fast next-day delivery, trustworthy delivery partners & secure packaging
  • Quick & easy 60 days returns

We are more than online retailers. We have a passion for playing, making, and recording music. We only sell On-Stage® products that we would be happy to use and that you can rely upon.

Read All About Us HERE>

Description

Compact Personal Headphone Amplifier With High Output Power For Loud, Clear Monitoring – On-Stage Headphone Amp

The On-Stage Headphone Amp is a compact, reliable personal headphone amplifier built for musicians, vocalists, and audio professionals who need loud, clear monitoring in live, rehearsal, studio, or silent practice scenarios. Its high-output amplifier (up to 200 mW per channel) drives any headphones powerfully—even high-impedance models—ensuring every detail is heard without distortion, while the stereo/mono switch and auxiliary input allow mixing in backing tracks, metronomes, or external sources for versatile use.

Battery Powered and Easy To Use

Powered by a 9V battery or optional DC adapter, it offers true portability without cables or outlets, and the rugged metal chassis with rubber feet withstands stage knocks and floor placement. Simple knob control keeps operation intuitive, making it ideal for drummers, keyboardists, guitarists in silent practice, live monitor mixes, schools, churches, or any situation requiring private, high-quality headphone monitoring.

Flexible Monitoring

Stereo/mono switch and aux input enable custom mixes; high power ensures clarity even in noisy environments.

Portability & Durability

Battery operation for off-grid use; tough metal build protects against gig wear and tear.

KEY FEATURES: On-Stage HA4000 - 4 Channel Pro Headphone Amplifier
  • High Output Power: Delivers up to 200 mW per channel for driving any headphones loud and clear, even high-impedance models.
  • Stereo/Mono Switch: Selects stereo or mono monitoring for flexibility in live or rehearsal use.
  • Auxiliary Input: 3.5 mm stereo aux in for mixing external audio (e.g., metronome, backing tracks) with main signal.
  • Battery & DC Power: Runs on 9V battery (included) or optional 9V DC adapter (not included) for portable or fixed setups.
  • Level Control: Independent volume knob for precise personal monitoring without affecting others.
  • Rugged Build: Durable metal chassis with rubber feet for stability and protection on stage or floor.

Specification
  • Type: Personal headphone amplifier
  • Inputs: 1 × 1/4" stereo TRS line in, 1 × 3.5 mm stereo aux in
  • Outputs: 1 × 1/4" stereo headphone jack
  • Power Output: Up to 200 mW per channel (into 32 Ω)
  • Power Supply: 9V battery (included) or 9V DC centre-negative adapter (not included)
  • Controls: Volume knob, stereo/mono switch
  • Frequency Response: 20 Hz–20 kHz (±1 dB)
  • Construction: Metal chassis with rubber feet
  • Dimensions: Approx. 114 × 76 × 38 mm (typical compact size)
  • Weight: Approx. 0.3–0.4 kg
  • Applications: Live monitoring, silent practice, rehearsal, studio cueing
  • Additional: No phantom power or mic preamp; line-level only

What's in the box?
  • On-Stage HA4000 Headphone Amp
  • 9V battery (installed)

Downloads & Manuals

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Really happy with the PC and the service received. Communication was excellent throughout the build process. All delivered in good time and received with plenty of helpful advice, especially from Kieran after delivery to help me set it up.

Will definitely recommend. Many thanks

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Need help? Call us on: 02476 36 98 97

We are more than online retailers, our sales staff have a passion for making music and give honest, frank feedback on their experience with your chosen product.

OPEN: Mon to Fri - 9am to 5pm (Closed Sat/Sun)

CONTACT US NOW
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