hulk-
more so with mic pre's but one thing to think about with component selection is where the components are sitting in the circuit wth regards to amplifier stages. Anything that gets passed through an inputt transformer in a mic pre gets amplified HUGE amounts, so whatever color you pick up on the way in is going to be made bigger. If you have a line input transformer into a circuit running at unity, there's less amplification, so less of the transformer sound is being amplified. Of course, you can get a line transformer with tons of color that will color the box at unity more than another mic input transformer will with 70dB of gain following it, but its something to think about.
Carbon Comp resistors have a rep for being noisy, if you use all metal film resistors in a box, but use carbon comp on the input and first opamp in a dual opamp circuit, you are going to hear more noise I would think than if you use metal film on the amplifier stages and then carbon comp on the tail once you've done the bulk of your amplifying. Same holds true for audio coupling caps. You might want to use something like an FC throughout the entire circuit to get as much high end going on as possible and then use an output coupling cap that wont pass as much high end material. I bet if you built a box like that, your imaging would be different thhan if you used midrange sensitive caps throughout with a top sensitive output coupling cap. Im not suggesting one way is better than another, merely that it may amount to a difference.
There are broad strokes to be painted for sure, but Ive found it helpful to look at where the amplifiication is happening and mak decisions based around that.
hopefully this makes some sense and isnt confusing.
dave
more so with mic pre's but one thing to think about with component selection is where the components are sitting in the circuit wth regards to amplifier stages. Anything that gets passed through an inputt transformer in a mic pre gets amplified HUGE amounts, so whatever color you pick up on the way in is going to be made bigger. If you have a line input transformer into a circuit running at unity, there's less amplification, so less of the transformer sound is being amplified. Of course, you can get a line transformer with tons of color that will color the box at unity more than another mic input transformer will with 70dB of gain following it, but its something to think about.
Carbon Comp resistors have a rep for being noisy, if you use all metal film resistors in a box, but use carbon comp on the input and first opamp in a dual opamp circuit, you are going to hear more noise I would think than if you use metal film on the amplifier stages and then carbon comp on the tail once you've done the bulk of your amplifying. Same holds true for audio coupling caps. You might want to use something like an FC throughout the entire circuit to get as much high end going on as possible and then use an output coupling cap that wont pass as much high end material. I bet if you built a box like that, your imaging would be different thhan if you used midrange sensitive caps throughout with a top sensitive output coupling cap. Im not suggesting one way is better than another, merely that it may amount to a difference.
There are broad strokes to be painted for sure, but Ive found it helpful to look at where the amplifiication is happening and mak decisions based around that.
hopefully this makes some sense and isnt confusing.
dave
