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Never one to have too few incomplete projects at any given time I've been thinking about what do with some old stuff I have knocking about. The first amp I ever built (a MadAmp A15mk2 kit, terrible experience) doesn't get any use at all. The B+ is a little too low for the sort of preamps I use and generally speaking I have no use for a 15W amp. However I do tinker with making rack preamps and a rack poweramp would be a nice thing to match it with for tinkering purposes when using my 2xKT88 poweramp would be silly.
Now this got me thinking. What if I add a dummy load with a line out to the power amp? I could then take the line out signal and feed it to a large SS power amp powering my T100 loaded 412. My thinking being that if I get the power amp and dummy load right I could have a rig that would sound great at a range of volumes (acceptable to excessive - mainly excessive, I'm childish like that). There are a few options as I can see it:
1) Purely resistive. A 50W 15R aluminium clad resistor and an isolation transformer with maybe some tone shaping thrown in should work. I know that Steve Conner has done something like this:
A simple speaker simulator
2) Reactive load. Do something like Aiken presents on his website and then cobble a line out onto it. I'm not too sure how to go about the last part. Do I simply add an isolation transformer?
3) Do something like the Palmer PDI-03. This looks to a reactive load of sorts which then has an isolation transformer feeding two circuits; one is a line out and the other has fancy filtering in to emulate a speaker. This is probably overkill since it will eventually come out of some guitar speakers anyway.
So what are folks opinions on this? Is there much advantage to going down the reactive load route here? Has anyone tried the two methods for similar nefarious purposes?
Cheers
Ian
Now this got me thinking. What if I add a dummy load with a line out to the power amp? I could then take the line out signal and feed it to a large SS power amp powering my T100 loaded 412. My thinking being that if I get the power amp and dummy load right I could have a rig that would sound great at a range of volumes (acceptable to excessive - mainly excessive, I'm childish like that). There are a few options as I can see it:
1) Purely resistive. A 50W 15R aluminium clad resistor and an isolation transformer with maybe some tone shaping thrown in should work. I know that Steve Conner has done something like this:
A simple speaker simulator
2) Reactive load. Do something like Aiken presents on his website and then cobble a line out onto it. I'm not too sure how to go about the last part. Do I simply add an isolation transformer?
3) Do something like the Palmer PDI-03. This looks to a reactive load of sorts which then has an isolation transformer feeding two circuits; one is a line out and the other has fancy filtering in to emulate a speaker. This is probably overkill since it will eventually come out of some guitar speakers anyway.
So what are folks opinions on this? Is there much advantage to going down the reactive load route here? Has anyone tried the two methods for similar nefarious purposes?
Cheers
Ian