f.a.q. 2017-11-05T23:34:09+00:00
LED colors on the preamp, what do they mean? 2017-11-14T08:29:03+00:00

The color of the rind-LED’s indicate the bypass state of the different sections within the pre amplifier: mute, fx-loop and tone control.

  • Red: section bypassed
  • Green: section active

A blinking tone control LED indicates the state of the user-selectable sound signature. By pressing and holding the mute button for 1 second, the tone control LED will blink red / green, indicating the current state. Pressing the tone control button while holding the mute button will toggle the sound signature and therefor the LED’s color.

  • Red: sound signature disabled
  • Green: sound signature enabled

During startup, the LED’s one by one gradually fade from red to green to indicate warmup.

LED colors on the poweramp, what do they mean? 2017-11-14T08:07:39+00:00

The color of the ring-LED on the power amp’s frontpanel indicates the different states of the amp. If an error is detected, it will blink in specific patterns as well.

  • Red: initial startup
  • Orange: power tubes are warming up their perfect operating point
  • Green: everything is warm and fine

It’s possible the LED goes from green back to orange again. This is perfectly fine and is just the amp making some minor adjustments. See the article: Automated bias for more information


  • Blue/orange: fan is blocked or defective. Please check if it’s working correctly. Amp will shut down after 1 minute otherwise.
  • Blue/red: the amp has shutdown due to a fan error.
  • Red/off: no bias voltage. The amp has shutdown to prevent serious damage to the power tubes

In all error cases, it’s imperative to have the amplifier checked by an engineer or service technician. Or contact me directly for more information.

Line out phase switch. What does it do? 2017-11-05T10:03:28+00:00

The line out phase switch is important when playing on stage through both your own cabs ánd the front of house.

The phase of a signal determines it’s timing. Depending on a lot of variables in the signal path to both your cabinets and the FOH mixing console, the timing for one of them can be ‘out of phase’. Two signals that are out of phase tend to cancel each other out. In this case, resulting in a very loose, vague and muddy sound for the audience. Switching the line out phase selector eliminates this problem.

FX loop phase switch. What does it do? 2017-11-05T10:03:47+00:00

The pre amplifier utilizes a full parallel, mixable effects loop. To be able to mix the clean- and effects signals, they need to have the same phase (timing of the signal). If they have opposite  phase, they will cancel each other out. This can be heard when the output reduces to (near) zero when setting the mix control halfway. Switching the fx loop phase selector eliminates the problem.

There’s a long list of effects pedals that invert the phase: https://www.thegearpage.net/board/index.php?threads/list-the-pedals-that-invert-phase.796444/


Connecting multiple speakers 2017-11-05T10:04:25+00:00

When connecting multiple speakers (daisy chaining), you need to make sure you’re using the right amplifier output. To get the correct value, you need the divide the impedances bij the amount of speakers, assuming all speakers have the same impedance rating (as they should). So two speakers with an 8 ohm rating, will total as a 4 ohm load, so connect to the 4 ohm speaker output on the amplifier.

Do not use more than one amplifier output at the same time to connect multiple speakers! This wíll damage the amplifier.

Speaker loads 2017-11-05T10:04:40+00:00

The power amplifiers support speaker loads with an impedance of 2, 4 and 8 ohm. You can usually find the impedance rating on the back of your cabinet. For best performance, connect your speaker to the matching amplifier output, as indicated on the backside.

There’s no harm done to the amplifier if you connect your speaker to a different output impedance, but the sound will be completely wrong and the actual power output is either higher or lower than the rated output. This can reduce the volume significantly, or damage the speaker if the actual output exceeds the speaker’s rating.

Do not use more than one amplifier output at the same time to connect multiple speakers! This wíll damage the amplifier.

Are the amps compatible with 115V/230V mains voltage (and the likes)? 2017-11-05T10:04:49+00:00

Yes, every amplifier is fitted with a selector switch on the backside for 115/230V. Countries with 115V or 120V mains should use the 115V setting. Countries with 220V, 230V or 240V should use the 230V setting. Never(!) use the amp with the wrong setting. It will destroy the power supply.

Where’s the standby switch? 2017-11-05T10:05:02+00:00

There is no, nor will there ever be a standby switch on a deBont bass amp. And with (very) good reason. The standby switch is an object of myth, misconception and misuse. Read all about in the article; “Standby switches, and why we can (and should) do without”