Weber Mass III 150W Power Attenuator – Used


Weber Mass III 150W Power Attenuator – Used

Type: Used
Condition: Good

Weber Mass III 150w Power Attenuator for Tube Guitar and Bass Amplifiers up to 80w (40w recommended).

Get massive tube tone at neighborhood friendly volumes.

May be used on 4, 8, and 16 ohm amplifiers. This MASS III is unique in that it has an actual tone stack for the speaker signal – BASS – MIDS – TREBLE. It also has the internal speaker motor for the load, and has a variable line out signal with volume and tone. The unit has two speaker output jacks to support multiple cabinets. The three tone controls can take the signal from whisper quiet to full on with slight humps in the bass, mids, and treble.

Additionally, the MASS III has an active bypass circuit with a footswitch so you can run attenuated or bypassed. The power pack for the switching relays is a 7.5VDC wall wart. With no power applied, the attenuator is still usable. The power is just for the footswitch circuitry. We include the power plug but the footswitch itself is not included. You can use any latching footswitch, including one incorporated in a multi-effect floor unit.

There is an option to add a headphone output, and this adds an extra jack with an independent volume control.

Like all Weber attenuators, you can turn all attenuator controls to zero, pull the speaker, and just use the line out, making the MASS III a dummy load.

Optional wings may be employed for rackmounting the MASS III. Attach these wings to the sides of your attenuator, and you can mount it in a standard 19″ rack. Uses two rack spaces. Must place the attenuator on the topmost spaces of the rack to allow proper ventilation.

This item is hand-built to order, to ensure the best attention to detail is paid to its construction. They are built one at a time, on a table, not hundreds at a time on an assembly line.

IMPORTANT NOTE ABOUT HIGH GAIN AMPS: (if you have a Fender or similar amp, and play with cleaner tones, this part does not apply to you). High gain amps such as Marshall or clones (with heavy distortion) are hard on attenuators. Unfortunately, an amp’s volume dial is not a good indicator of how much power is being produced. Many amps can reach full power at 3 or 4 on the volume dial, so it is a good suggestion to get an attenuator with 4x the power handling. For example, if you have a 50w high gain amp, you should opt for the MASS 200. Do not attenuate too far down. this puts a lot of power through a very small section of the volume rheostat which can cause it to fail. Also, do not turn your amp all the way up. even if you’re just knocking a little off the top with the attenuator, it’s a good idea to keep the amp somewhere in the middle at most. It’s best to find the lowest volume on the amp that is the acceptable tone to you, and then use the attenuator to bring it the rest of the way.

– Designed for use with 80 watts amps and lower (40w or lower is ideal)
– Works with 4, 8, 16 ohm
– Active Bypass Circuit, footswitchable

Updated January 26, 2022 at 12:17 PM

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