> is that clean enough? .... What exactly am I looking for?
Sometimes you don't know what you are looking for. But anything "odd" may be a clue.
We are tracing a many-stage system looking for a problem. Let us say there is poor water flow in the upstairs bathroom. You would check for water at the street, at your meter, at your downstairs faucet, etc. If the complaint is "no" water upstairs, you could drill holes (or loosen fittings) to check for water at intermediate points. If "here" makes your shoes wet and "over here" leaves them dry, you have narrowed the problem to that length of pipe. If the complaint is "weak water" you may need a "better" gauge than just wet shoes, you might use something that can tell 40psi from 20psi.
I have been getting ice-cream hard as a rock. I thought it was my freezer and power failures. Then I found a tub from 2013 which was fine! So my freezer isn't the problem. I should backtrack to the supermarket, try a tub from the case. Then a tub from the back room. (I suspect the stock-clerks leave the stuff out while re-stocking.) Of course if the back-room tub is hard I should track the truck and warehouses all the way to Ben and Jerry's factory. SOMEWHERE the ice-cream is good and then bad at the next stage. (I assume B&J don't make this much bad ice-cream. But always doubt your own sources. Saw a report of a "pedal problem" traced to *two* part-bad guitars.)
If the complaint is "precision", like a lab process needs 40psi and 39psi won't do, then you need a real good gauge. Your Blackstar may not be "clean" enough to resolve 0.1% from 0.2% distortion. But most guitar amp troubleshooting is "gross" problems, sound goes from "good" to "echh!".
It would be wise to track-through a "good" amplifier first to get a sense where to poke and how the signal gets louder through amplifier stages and softer after tonestacks and other knobs. And how even a good amplifier can be "made" to sound bad if pushed too hard.)
Topic: Building/Using a Listening Amp (Read 4601 times)