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View Full Version : Attenuators? premature amp death, or safe?



redgibson
February 1st, 2010, 03:53 PM
There seems to be a mix of literature on the web proclaiming an attenuator will possibly ruin your amplifier, blw your tubes etc, and the converse that they are just fine. Anyone have a personal experience one way or the other? I'd like to crank my HRDx into creamy tube nastyness and not melt my neighbor's face off. (apartment living...) thinking something like the Dr. Z Brake Lite, says it supports up to 45 watt amps so I sneak just under at 40watts. Bring on the tales of flaming amp death OR complete apartment jammin' bliss as woman tone belts from the speaker in a happy and safe manner :-)

kiteman
February 1st, 2010, 04:20 PM
You have to realize that if you use the attenuator and crank your amp up your tubes will wear faster just like being on the stage playing loud.

There's active attenuators and the passive ones. The active ones have speaker coils inside providing a load to the amp. The passive ones I think just provides resistance.

sumitomo
February 1st, 2010, 05:11 PM
You also have to remember that it will lower the volume,but in an apt enviroment it's still going to be loud.I use one in my house on a Blues Jr..I would look into that Mack Gem for apartment living,it just may be the ticket for your living setup.Sumi:D

tunghaichuan
February 1st, 2010, 05:45 PM
Attenuators are kind of a mixed bag. There are two types: resistive and reactive. The resistive types are just a bunch of power resistors wired so that they dissipate heat. The Tom Scholtz Power Soak is an example of this

The reactive types use either a coil or a speaker motor (Weber) to simulate the reactance of a speaker. Weber's MASS and Mini-MASS are examples.

The resistance is important because your tube amp needs to have some kind of load, be it a speaker or a bunch of resistors.

Some amps, like Fender are traditionally more tolerant when using attenuators, others like Marshall tend to blow up output transformers.

Remember, running your amp full out into a speaker attenuator is kind of confusing because the amp is putting out maximum power, but the level is low so that it doesn't seem like the amp is working hard at all. At the very least, you will wear out tubes a lot faster, as Kiteman says.

I used to own several of the Power Soaks, and now have a Mini-MASS. The don't really sound that good at low volumes. Attenuators are useful for knocking down a few dB to get a better OD sound at lower volumes, but they don't work well for for whisper quiet volumes.

For low volume OD, you may want to try out this product, the VVR3:

http://www.hallamplification.com/main.html?src=%2F#2,2

I've never tried it, but others have said that it works well. If you can't perform the install, you will definitely want to have a tech install it.




There seems to be a mix of literature on the web proclaiming an attenuator will possibly ruin your amplifier, blw your tubes etc, and the converse that they are just fine. Anyone have a personal experience one way or the other? I'd like to crank my HRDx into creamy tube nastyness and not melt my neighbor's face off. (apartment living...) thinking something like the Dr. Z Brake Lite, says it supports up to 45 watt amps so I sneak just under at 40watts. Bring on the tales of flaming amp death OR complete apartment jammin' bliss as woman tone belts from the speaker in a happy and safe manner :-)

FrankenFretter
February 2nd, 2010, 08:07 AM
For low volume OD, you may want to try out this product, the VVR3:

http://www.hallamplification.com/main.html?src=%2F#2,2

I've never tried it, but others have said that it works well. If you can't perform the install, you will definitely want to have a tech install it.

Would this be similar to EVHs use of a Variac back in the good old days?

tunghaichuan
February 2nd, 2010, 09:06 AM
Would this be similar to EVHs use of a Variac back in the good old days?

It is similar in that it reduces the high voltage power supply and as a result reduces power out and overall volume.

However, a Variac reduces all the voltages in the amp, filaments included. The filaments like to operate in a specific range. Too much or too little filament voltage shortens the tube life significantly. A variac is simply a variable voltage transformer that you plug the amp's power cord into.

The VVR reduces the high voltage and bias voltage, but doesn't mess with the filament voltage.

danohat
February 9th, 2010, 07:46 AM
Tube amps just don't go hand in hand with apartment dwelling. You might as well get yourself a modelling amp for this type of practice situation.

Plank_Spanker
February 9th, 2010, 05:40 PM
Agreed.

While there are varying degrees of attenuators out there, I don't think a single one of them will tame even a low wattage tube amp to bedroom / apartment levels without the sound and response suffering.

Most attenuators are meant to shave off some the clean headroom of tube amps to allow you to dial in your "sweet spot" drive / distortion settings at less than thunderous volume levels for live work - just a notch or two of attennuation......................they are not meant to bridle an amp down to bedroom levels and still retain sound quality.

If you seek bedroom / apartment sound levels with an attenuator, seek elsewhere.................heavy attenuation really squashes the life out an amp's tone.