Custom Built Dr. Ho Guitar Amp Attenuator / Speaker Volume Control - Black / Brushed Aluminum

Ho’s Electronics Custom Guitar Amp Attenuator / Re-Amplifier

Hand-built Vancouver amplifier volume-control unit with variable output and Send/Return loop

This is a custom-built guitar amplifier attenuator/re-amplifier attributed to Ho’s Electronics of Vancouver, BC, built by YuKong Ho. Ho’s attenuators have a long-standing reputation among guitar players in the Vancouver area and are closely associated with the design that became known commercially as the Ultimate Attenuator.

The design is intended to let a guitarist drive a tube amplifier harder while controlling the final volume sent to the speaker cabinet. Ho’s documented attenuator designs use a load followed by a solid-state re-amplification stage, allowing continuously variable output rather than fixed attenuation steps.

This particular example appears to be a custom configuration with a simple front-panel volume control plus rear AMP, SPEAKER, SEND, and RETURN connections.

Condition:

Good physical condition overall with normal signs of previous use, including some light scratches and scuffs on the brushed aluminum front/rear panels and black enclosure. There are no major dents, cracks or significant physical damage visible.

The front power switch, green power indicator, variable control, rear connections and permanently attached AC power cord all appear physically intact. The green power indicator illuminates as shown in the photos.

Full audio/attenuation testing was not specified, so I would not state that the complete signal path has been fully tested unless you confirm that separately.

Includes:

• Ho’s Electronics custom guitar amplifier attenuator/re-amplifier
• Permanently attached AC power cable
• Not included: Speaker cables, instrument cables, pedals, footswitch, original box, paperwork or other accessories

Key Features:

• Custom Ho’s Electronics build: Hand-built Vancouver amplifier accessory associated with YuKong Ho.
• Variable output control: Front-panel rotary control provides continuous level adjustment.
• Active re-amplifying design: Ho’s attenuators are known for reducing the amp signal and re-amplifying it to the desired speaker level.
• AMP input: Dedicated rear connection for the amplifier’s speaker output.
• SPEAKER output: Dedicated connection to the external speaker cabinet.
• SEND / RETURN connections: Provides external loop routing, an option documented on other custom Ho attenuators.
• Powered operation: Built-in AC power cable, front power switch and indicator LED.
• Heavy-duty enclosure: Metal chassis with brushed aluminum panels and rubber feet.

Technical Specifications:

• Builder: Ho’s Electronics / YuKong Ho
• Product type: Guitar amplifier attenuator / re-amplifier
• Model: Custom-built; exact model unknown
• Origin: Vancouver/Burnaby, British Columbia, Canada
• Front controls: Power switch, power LED, variable level control
• Rear connections: AMP, SPEAKER, SEND and RETURN
• Additional rear control: Unlabelled rotary control; exact function unknown
• Power: Permanently attached AC mains cable
• Maximum amplifier wattage: Not marked / unknown
• Impedance rating: Not marked / unknown

Frequently Asked Questions:

Q: What is this unit used for?
A: It is designed to let a guitarist run a tube amplifier harder while controlling how loud the connected speaker cabinet becomes. This allows more of the amplifier’s power-stage character to be used at more manageable volume levels.

Q: Is this a normal passive attenuator?
A: Ho’s best-known attenuator design is actually a re-amplifying system: the amplifier signal is loaded down and then passed through a solid-state amplification stage to the speaker.

Q: What are the SEND and RETURN connections for?
A: They provide an external loop between stages of the unit. Effects-loop versions were one of the custom options offered on other Ho attenuators.

Q: What wattage and speaker impedance does this unit support?
A: The exact rating is unknown. Ho built different 50W, 100W and higher-powered custom units, but this particular example has no visible wattage or impedance marking, so buyers should not assume a specific rating.

Q: Does it require power?
A: Yes. This is an active unit with a permanently attached AC power cable, front power switch and power indicator.