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Ultimate Attenuator Review

Ultimate Attenuator brings your loud tube amps to reasonable volumes

Ultimate Attenuator We are very fortunate these days in the world of getting great tone. It has always been a bit of science mixed with art, and occasionally a bit of mojo thrown in for good measure. Now we have at our disposal some great tools to make this job easier. The Ultimate Attenuator is certainly one of these tools.

A bit of history
For years, we have all known that turning up the amp and driving the tube power section harder will produce some great overdrive and distortion tones, as well as those on-the-edge clean tones we all love for Blues and Country music. The first attenuator devices appeared in the seventies. They weren’t much more than a resistor used to convert some of the amp’s power into heat. They did work, but provided what is called a resistive load to the amp. A solid non-changing load on the amp’s output did not allow the amp to “breathe” as it went through the many different frequencies it was called on to produce. This often caused amp failure. Marshall amps in the late seventies even came with a white paper tag on the handle that stated, “warranty void if used with attenuation devices.”

A few years ago a new breed of attenuators was born: reactive load attenuators. There are a few very fine units of this type on the market right now. The bottom line, however, is always “how does it sound?” There are two common complaints. The first is that it changes the tone, and the second is that it changes the feel and dynamics. The first complaint is not what it seems. I could go on and talk about the Fletcher Munson Curve, which is the way our ear perceives tone at different volume levels, but there isn’t enough space here.

The Ultimate Attenuator is the first unit to use its type of design to lower volume. A reactive load is provided that doesn’t need to have an impedance selector switch on the unit. It works well with all impedance settings. What makes this even more interesting is that if you do have an amp with selectable impedance, changing the settings will produce different responses. These will vary both in tone and feel. I have been using one of these units for quite a while with several types of amps, and have had no problems or amp failures. I am not aware of anyone else having any either. So, I have to say that it is very reliable.

The attenuated signal is sent to a very remarkable, 100-watt even response amplifier in the Ultimate Attenuator’s chassis, with a volume control for the unit, so as you turn it down there is no change of resistance to cause a change in tone and dynamics. Instead of using graduated notch settings as on some other units, it is a smooth taper, bringing the level to exactly where you need it to be.

The unit is very well constructed and does come with some very cool options, such as a “Plexi” switch for changing top end response. There is also an optional 100-volt output power plug in the back, which cuts the input voltage to your amp to only 100 volts, as with a Variac. This starves the amp and produces a bit more compression and harmonics. It works very well with an older non-master volume Marshall amp. Think brown sound. Although my unit did not have this option installed, there is also a “bedroom switch” available for extremely low volume settings that still retain the tone.

Once again on the subject of very low volume: remember that the attenuator is basically used to get the amp down to a useable room or club volume. If you turn the volume of the unit all the way off and then bring it up in very small increments so the sound barely comes out of the speaker, you’re not using the unit for what it was designed to do. It is always helpful to push your speaker a bit. The maker, Mark Gregg, is very easy to communicate with, and he has some very special surprises coming up for us in the future.

The Final Mojo
I find the Ultimate Attenuator to be the most transparent unit I have heard. It most reliably reduced the volume without changing the tone, keeping in mind the above-mentioned curve. It won’t harm your amp, and it is very reliable.

Buy if...
you''re looking for a way to harness that big or medium wattage amp and make it useable at normal loudness levels.
Skip if...
you have a transistor amp, as it is not recommended for solid state amps.

Base Price $449 As Reviewed $699 - Ultimate Attenuators -

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