It looks like you're new here. If you want to get involved, click one of these buttons!
Subscribe to our Patreon, and get image uploads with no ads on the site!
Base theme by DesignModo & ported to Powered by Vanilla by Chris Ireland, modified by the "theFB" team.
Comments
There are quite a few notches between min and max attenuation on the Power Brake. The first 3 or 4 are great and don't alter the sound too much, but beyond that it starts to lose both lower and higher frequencies and generally sounds a bit crap.
Basically, I found that turning the amp up to 11 and then using a high attenuation setting didn't sound too good - it was more about finding the sweet spot of the volume I needed without compromising the sound of the amp too much. YMMV with other units of course.
The OP will want something more modern with a line output though - I'm not too familiar with most of those unfortunately.
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
To play devil's advocate though, I can turn the amp down to just over 1, add a drive pedal and it sounds more or less as good without faffing with any attenuation, and way better than several 'low' wattage 'bedroom' valve amps I've owned or tried.
I've usually found attenuating a maxed amp down to talking volume sounds pants.
Regarding attenuators, I've only tried the Harley Benton one but it took away all the treble when trying to get down to home volumes...
I have been pulling out my seldom used, 32 year old JCM900 mk3 master volume amp, which I had previously used only at home, with a fairly clean setting, through a Weber Mass150, which I picked up because at the time, it was regarded as one of the best non tone sucking attenuators. It has dials for lows / mids and mids / highs, and a switch for low / high range? and a bypass. Connections at the back are for input, line out and 2 speakers, no impedance selection.
I have the manual somewhere, and it says impedance can be ignored with this device, it uses resistance as a load, plus a speaker motor for a more natural response.
Anyhow, that is how i used it last, but recently I wanted to just fire up the JCM to see how (if ) it works, and what condition it is in internally. Been bingeing on amp repair vids, so I thought I knew what I should be looking at.
Everything looked fine, so I cleaned pots, inputs etc, and visually inspected caps-good to go.
At this point I was not using the Weber, as it had developed a fault where one of the large pots would not rotate, seemed to be stuck in a position, so I hooked up the Marshall to a Powerbrake which was not getting much use, and went into a single Class5 cab, which is a 10 inch speaker rated at 15 watts, 16 ohm.
The Powerbrake has a switch for 8-16 ohm, and so has the JCM, so all looked good, all knobs on the Marshall were set to 12 o clock, which is 50%, and I fired it up, watching the valves very closely for anything looking hot.
BTW, this is a 50 watt amp, which has always been used at half power to reduce volume, and this time I was using the amp at full power, and had the Powerbrake at position 1, which is one above silent.
In short, the sound was excellent, but still a touch too loud, and had just a little too much gain, but it was the first time I have really used this amp for any type of driven sound, always tending towards something digital at home.
That was a couple of weeks ago, and today I have just spent an hour looking at what is going on, and I think I may have had a bit of a revelation here.
The 'gain' sensitivity knob on a JCM900 mk 3, is basically the mod done to a JCM800 to get more gain from that amp, which in turn was basically a JMP in a new shell, early amps had the same circuit, so basically a direct descendant of JTM45, / Bassman circuit. That is how I can understand the lineage anyway, the Marshall has the tone stack in a different stage, and is using different components, but is basically the same, simple circuit.
Less components = cleaner signal, more dependant on component variables.
My revelation came when I turned the gain comp to 0, so essentially JCM800, with all other knobs set to 50%, and the sound was perfect to my ears, just a little too loud. Powerbrake will not go any quieter ( off is position 1), so my hypothesis is that the amp was designed to be neutral, or optimum, however you describe it, with everything at 12 o clock, allowing equal adjustment at either end.
The pre amp and master sections are both set mid way, which allows either more, or less gain and volume, and the actual DB vol is determined by speaker selection and load.
I realise this might be just a weird coincidence, and all settings are obviously adjustable to taste, but it makes sense that the sweet spot for all pots would be factory designed to be 50%, and these things are designed to be a certain loudness, for a very specific use-the stage and a live drummer.
I don't think I will be trying out my hypothesis any time soon, but now I at least know to just set all knobs to 12, use Powerbrake at 1, and run into a 15 watt, 10 inch speaker.
This is giving me the loud, clear tone that I like, and allows me to use various pedals to shape the drive tone, ie Klone into Guvner, and of course depends on the guitar used, I used my Frankenstein, with an EVH franky bridge pickup, and a stacked Seymour Duncan in the neck.
Sorry for the long winded explanation, but as far as the attenuation goes, the Weber's fault eventually turned out to be one of the resistors inside, which are just hanging around, wired in series ( or parallel-not sure which ) was fouling on the heavy duty resistor pot, I used a few tie wraps to tidy things up, but it is a very crudely built device, and I would sell it if I thought it would survive the journey--no chance really, I don't know how it could have made it to me from the USA via the BBC ( E-bay ) and actually worked in the first place.
I had been using the Powerbrake to tame a 5 watt Marshall class5 head into a 4 x 12, for my loud clean platform, and I shall now be trying to use the Weber for that set up instead, the Powerbrake is the perfect partner for the JCM900, and is something I will be playing about with again.
My only concerns at this stage, is finding somebody local who I can actually trust to get this valve stuff serviced, and is another reason why I wouldn't want an amp to be running at anything other than it's optimum, ticking over.
Running stuff flat out is not really necessary in this day and age, but if you are happy to put extra strain on the equipment, it's all part of the fun.
I think Marshall designed their stuff to be optimum at settings of 50%, is my theory.
So really the SV20 seems to me to be a modern plexi, with Origin a plexi style, and would just be more accurate. Of course being plexi it needs attenuation to use at home.
Probably not. Some people seem to hear it differently. Personally, I don't mind attenuation at all - in fact I find I can often get *better* sounds with it than without - but some people hate it (even the same combinations of amps and attenuators) and say it kills the tone.
For me it sounds better than power scaling as well. I don't like scaling at all - which I know is also contrary to popular wisdom. In fact I prefer a traditional master volume to scaling...
Yes, hugely. I found the Origin mediocre-sounding and entirely uninspiring. The SV20 was really great for guitar-straight-in or with mild boost/overdrives, and sounded very much like a small Plexi - although it did compress too much and develop a 'one tone' sound at high volume with heavy fuzz and distortion.
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
(b) Brilliant, thanks. What do you mean by "one tone"? I think I sort of know what you mean, but just in case I've got the wrong end of the stick...
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein