I also own a RG-80 and at some point I wanted to find a way to cut the power somehow.

The main reason behind that is/was to use a vintage voiced, low-wattage speaker, because I prefer the way they sound and feel.  Of course, I could just put a 30 watt G12H speaker in there and make sure not to dime the amp (which would be unbearable anyway) but I just have a problem using an underspec'ed speaker.

The RG-80 is really a sleeper.  I doesn't make me miss any tube amp, and I had a couple nice vintage Fenders. 

teemuk,

Thanks for your very detailed reply.

I got a lot more info to get where I want now.

The DI box I use is one of those Behringer DI100 active DI's.  It can take a very high wattage and has 2x -20db attenuation pads available.

Your right about the signal output jack on the RG-80.  I forgot about that.  I should try this first.

The service manual doesn't have any warnings about using the amp without a speaker load but says "less than 8 ohms load impedance not recommended".  Impedance load has always got me confused so I don't know what to make of this.

As for the speaker acting as an electric and acoustic filter, I know I'll have to use some sort of cabinet simulation.  Some DI's have some internal cab sim circuits or I can just use some eq or even plugin in my DAW.  The electric filter part has me wondering if getting one of those MASS devices from Weber VST would be useful.  It is an attenuator with an actual speaker motor in order to replicate the non-linear impedance load of a real speaker (or something like that...).  These are intended for use with tube amps so I don't know if it's relevant or maybe even harmful to a ss amplifier.

So I just need to make sure unplugging the speaker is safe to try this out.

Hi,

Newbie here, newly converted to the beauty of ss guitar amps.

I would like to use my RG-80 combo as a recording preamp.  The goal is of course to plug-in directly into a di box into my recording interface while disconnecting the speaker to record silently.

My question is : How should I go about doing that.

1- Should I use the speaker out jack or the effect send from the amp to the di box?

2- What about the speaker load?  Do I need some sort of load compensation for the power amp?

Maybe I'm missing something so feel free to add any other consideration to the discussion.

Many thanks.