Orange OB1-500 Bass Amplifier Head (500 Watts)

Get bi-amping tone with one small rackmount. The OB1-500's footswitchable blend circuit keeps your low end clean while adding high-end harmonics and gain.

For years bassists have been combining guitar and bass amps to remarkable effect, adding harmonics and layers of overdrive from a guitar amp to their core bass tone in pursuit of the ultimate live sound. This 'bi-amp' trend got the folks at Orange thinking... Why drag two amps to the show when you could take just one? The result is the OB1 Series of class A/B rack mountable bass heads which take care of this and much more besides.

The key to the OB1's unique sound is a footswitchable Blend circuit which adds a veneer of controllable gain and increased harmonic content to the upper registers of the input signal. The lower frequencies and clean signal are left alone, staying warm and clear just as they would be in a 'bi-amped' setup. Depending on where the Gain and Blend controls are set, the possibilities are limitless. Punch in the Blend control to achieve anything from a transparent clean boost, to all-out filthy grind, and everywhere in between.

'Bi-amp' Inspired Design

The OB1 splits the input instrument signal into two separate paths. One side amplifies the clean signal, with all the clarity you would expect from Orange. The other adds up to two stages of distortion to the upper harmonics only, controllable via the amp's Gain knob. These two elements are combined using the amplifier's Blend control which adjusts the mix between clean and dirty. The Blend control can then be remotely engaged or defeated using the optional footswitch.

The Gain and Blend's range allows read more for almost anything, from a subtle level boost to cut through the mix, added girth and presence at moderate settings to fatten up chorus passages, to fully saturated savagery at the extremes. However you dial it, the OB1 always maintains the critical low end definition, right the way up to the most offensive settings!

Active EQ

The OB1's highly responsive active three band EQ has been meticulously voiced for maximum effect with minimal fuss. The EQ section is located after the Gain and Blend dials take effect, allowing full control over their massive sonic range. The Bass and Middle controls feature +/-15dB of boost or cut, whilst there is a range of +/- 20dB on the Treble control.

All Analogue Signal Path

The OB1 Series puts proper class A/B power back on the map. All circuitry is completely analogue, ensuring these amps sound expressive and musical even at ridiculous gain levels.

Rack Mountable

The OB1 Series are our first rack mountable amps, suitable for 19" cases (2U). Enclosed in a rugged power coated steel chassis the fascia is finished in our classic 'pics only' styling.

Balanced & Line Outputs

Balanced DI with ground lift and line level outputs for live and studio use.

Check the range of tonest The Orange OB-1 500 Bass Amplifier is capable of in this Soundcheck demo:


- Rack mountable (2U) 'bi-amp' inspired bass head
- Footswitchable Gain & Blend controls
- Active 3 band EQ
- Balanced DI & line level outputs
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- Front Panel (Right to Left): Instrument Input with Active/Passive Switch, Gain, Blend, Bass, Middle, Treble, Volume, Footswitch Input, Mains Switch
- Rear Panel (Right to Left): Speaker Outputs (Speakon), 1/4" Line Output, Balanced Output with Ground Lift Switch
- Speaker Output Options: Minimum 4 Ohms: 1 x 8 Ohm, 2 x 8 Ohm, 1 x 4 Ohm
- Output Power: 500 Watts, Class A/B
- Finish: White powder coated steel chassis (19" 2U Rack mountable)
- Dimensions (W x H x D): 48.2 x 26.5 x 10cm (18.97 x 10.43 x 3.93")
- Weight: 9.5kg (21lb)
Dimensions and Weight in Packaging
Base Item
Shipping Weight: 26.5 lbs
Shipping Dimensions: 22 x 15 x 8 in
Manufacturer Part Number (MPN): OB1-500

For support or warranty questions, please contact the manufacturer:
Phone: 404-303-8196

Reviewers gave this product an overall rating of 5 out of 5 stars. (5 ratings)
Submitted January 23, 2016 by Nyms Bacciarini in Goodyear, AZ

"Incredible amplifier..."

Overall: 5 out of 5 stars
(see rating details)
Verified Customer zZounds has verified that this reviewer made a purchase from us.
This amplifier is fantastic. I use it into an Orange 410 Cab. Bass response is smooth as glass but as you crank it louder the treble gets that growl but still keeps the smooth undistorted bass as if it's bi-amped into another amp and cab. I use a handbuilt (by me) Thunderbird Bass, a Hofner CT Beatle Bass, and a Samick bass with Fender PJ vintage pickups. Running the Beatle Bass into an Orange OB-1 500 is something you need to hear to believe... it sounds like the bass in 'Come Together' AND 'Sgt Peppers..' I went with the 500w instead of the 300w because 'a wee bit more..' is never a bad thing. It's a two rack space amp...don't put it in a two rack space case because it runs a wee hot. The amp has a large fan so I use a 3space case with the amp on the bottom and a 1 space slotted vent plate above the amp. It looks and sounds cooler than cool.... Hugs...Nyms

Musical Background:

Playing since the 60's, lead, rhythym, bass, drums

Musical Style:

Rock and blues
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