Morning all, any thoughts on the following please?
I have a Fender Power Chorus combo (early 90s, red knobs, 2x65W stereo, solid state) which sounds fab. However, it was designed to be gigged and is accordingly rather loud and way too loud for home use which means I've got the volumes on about number 1.
So here's to my question: can I use a power soak in this situation and would I need two as it's a stereo amp with 2x12" speakers (probably 8 ohm but I haven't checked yet)?
Also, would there be any point to it? Clearly the situation with a valve amp is different from this and I may just be over thinking it all. Anyhow, I don't suppose I'm the first person with a loud but lovely Fender Twin who has tried to tame it somewhat (somewatt???).
Thank you in anticipation.
Power soak on solid state combo?
Moderator: Moderators
Re: Power soak on solid state combo?
As a past power soak user (I used to have a Marshall Powerbrake) here are some observations:
On the whole power soaks are designed to be used on amps with Valve power amp sections so that you get the benefit of power amp valve distortion. You might get some benefit from using one on an amp with SS output stage, but if it's about getting more adjustability in volume at the lower end of the dial you might be better off looking at the replacing the master volume pot with one with a different taper characteristic that allows this.
If your combo has two discrete power amps (and it certainly sounds like it does) you would need a power soak on each.
On the whole power soaks are designed to be used on amps with Valve power amp sections so that you get the benefit of power amp valve distortion. You might get some benefit from using one on an amp with SS output stage, but if it's about getting more adjustability in volume at the lower end of the dial you might be better off looking at the replacing the master volume pot with one with a different taper characteristic that allows this.
If your combo has two discrete power amps (and it certainly sounds like it does) you would need a power soak on each.
RockinRollin' VampireMan
Re: Power soak on solid state combo?
Cannot find a "Power Chorus" but this, https://www.fmicassets.com/Damroot/Orig ... Chorus.pdf looks similar. 65WPCH.
As Red says, there is usually no tonal value in using a power soak on a solid state amp and it is possible it could damage the amp's power stages. There is however a much cheaper and safer alternative.
That manual shows two effects loops, one for mono and one for stereo operation. You can buy simple volume* controls that plug into said FX jacks and allow you to set a civilized volume level much more easily. The problem I am sure is as suggested in that a ***t or bust volume taper control has been fitted.
The possible danger in running sstate amps on loads is that they will be putting out close to their maximum power and even clipping at times. You are unlikely to do this directly into speakers because, as you say, the sound level is brutal and clipping transistor amps rarely sound good anyway. Even valve amps can 'red plate' under these conditions but valves are much more robust and forgiving than transistors!
*Beer into water to make if you can solder.
Dave.
As Red says, there is usually no tonal value in using a power soak on a solid state amp and it is possible it could damage the amp's power stages. There is however a much cheaper and safer alternative.
That manual shows two effects loops, one for mono and one for stereo operation. You can buy simple volume* controls that plug into said FX jacks and allow you to set a civilized volume level much more easily. The problem I am sure is as suggested in that a ***t or bust volume taper control has been fitted.
The possible danger in running sstate amps on loads is that they will be putting out close to their maximum power and even clipping at times. You are unlikely to do this directly into speakers because, as you say, the sound level is brutal and clipping transistor amps rarely sound good anyway. Even valve amps can 'red plate' under these conditions but valves are much more robust and forgiving than transistors!
*Beer into water to make if you can solder.
Dave.
Re: Power soak on solid state combo?
Edit: heavily edited since original reply
Here's the Power Chorus manual. https://www.fmicassets.com/Damroot/Orig ... s_1989.pdf
The volume control box in the effects loop works well. I used one on a Hot Rod Deluxe to good effect. The rear effects loop is before the stereo chorus, so you only need a single volume control box if plugged in there.
But that rear FX loop has a volume control, so you could try simply linking the input to the output using a standard TS to TS lead, setting the effect loop level to 'low' (-16dBv) and turning the rear gain control down to -9dB, which should give an extra degree of attenuation, which may be enough.
Without a volume box, if you have one, you could also try running a clean boost pedal or a compressor in the rear FX loop with the output set low, which should also attenuate the signal.
Fitting a standard TS to TS lead (not a TRS to TRS lead which will defeat the purpose of doing this) in the front stereo FX loop, should cut out the signal to one of the power amps/speakers, and so cut the level down by another 3dB.
You could also try pulling all of the faders down on the graphic EQ.
As has been said, as it’s a stereo amp you’d need to get two power soaks, one per speaker. Even a basic soak like the Thomann Harley Benton or the Bugera one, will end up costing more than £130 by the time you have bought two plus the extra speaker cables. For which money you could get a decent modelling practice amp.
What I'm not sure about is whether the speakers are connected via output jacks or are hardwired to the amp. As there is no mention of output jacks in the manual, I'd suspect a cost-cutting measure and they are hardwired. So you'd probably have to add output sockets to the amp before you could add power soaks.
And those basic power soaks are purely resistive and do compromise the amp tone.
Here's the Power Chorus manual. https://www.fmicassets.com/Damroot/Orig ... s_1989.pdf
The volume control box in the effects loop works well. I used one on a Hot Rod Deluxe to good effect. The rear effects loop is before the stereo chorus, so you only need a single volume control box if plugged in there.
But that rear FX loop has a volume control, so you could try simply linking the input to the output using a standard TS to TS lead, setting the effect loop level to 'low' (-16dBv) and turning the rear gain control down to -9dB, which should give an extra degree of attenuation, which may be enough.
Without a volume box, if you have one, you could also try running a clean boost pedal or a compressor in the rear FX loop with the output set low, which should also attenuate the signal.
Fitting a standard TS to TS lead (not a TRS to TRS lead which will defeat the purpose of doing this) in the front stereo FX loop, should cut out the signal to one of the power amps/speakers, and so cut the level down by another 3dB.
You could also try pulling all of the faders down on the graphic EQ.
As has been said, as it’s a stereo amp you’d need to get two power soaks, one per speaker. Even a basic soak like the Thomann Harley Benton or the Bugera one, will end up costing more than £130 by the time you have bought two plus the extra speaker cables. For which money you could get a decent modelling practice amp.
What I'm not sure about is whether the speakers are connected via output jacks or are hardwired to the amp. As there is no mention of output jacks in the manual, I'd suspect a cost-cutting measure and they are hardwired. So you'd probably have to add output sockets to the amp before you could add power soaks.
And those basic power soaks are purely resistive and do compromise the amp tone.
Reliably fallible.
Re: Power soak on solid state combo?
Thanks for that link Wonks.
Yes, there does not seem to be any speaker output jacks so accessing the power amps will be tricky. This is common practice on many solid state combos as it spares the makers from fitting sophisticated low load/short protection.
The combo also uses 8 Ohm speakers and that tells me the amplifiers were never designed to cope with lower loads and there must be plenty of Marshall style 4 by 12s about that can be switched to 4 Ohms.
Dave.
Yes, there does not seem to be any speaker output jacks so accessing the power amps will be tricky. This is common practice on many solid state combos as it spares the makers from fitting sophisticated low load/short protection.
The combo also uses 8 Ohm speakers and that tells me the amplifiers were never designed to cope with lower loads and there must be plenty of Marshall style 4 by 12s about that can be switched to 4 Ohms.
Dave.
Re: Power soak on solid state combo?
Thank you both for being as helpful as ever. Genius idea Wonks, I ran a patch cord in the rear fx loop and turned the level switch and level control all the way down and this made a huge difference. I also ordered a volume control from Chris at Lazy Bear which can just sit on top of my amp keeping things under control. So hopefully all sorted - cheers 
Once it sounds right stop!