Tube driven active mid boost?

[mtheory]

If a person wanted to build something into a tone stack that would allow a switchable, tube-driven, frequency sweepable mid boost, how would one go about that, do you think?

I'm imagining something along the lines of what you get when you leave a wah pedal cocked...something that will give a slight boost in a frequency range that could be dialed in, from say low mids to rangemaster treble.

Let's assume that we have a normal tone stack, let's say it's a TMB Marshall 18 watt, and we want to bring something like this into the circuit. Any ideas?

[selloutrr]

why a tube? both of the sounds you are asking for aren't tube driven if you want the wah sound use a dime stack like a wah does and then just add a pot to control the shift like your foot would.

[mtheory]

A wah uses a transistor to boost signal. I want to use a tube. True, the overall tone can certainly come from an inductor...maybe all I need is a tube-based wah circuit there? Good point.

[Bob-I]

When you look at the standard Fender tone stack, it's cut only but the next stage returns the gain sto the signal, making it an active EQ.

Look at the Dumble schematics in the Dumble files section. The mid boost lowers the value of the treble cap causing this to puch the mids at the next gain stage. It's very effective and easily tuned by adjusting the cap values.

[selloutrr]

if your after a great active eq check out the soundcity 120 there is an everything soundcity website with diagrams and schematics just google soundcity amps.

[Bob-I]

I've never seen that before. Looks very cool. That explains the unique charactor that Sound Shitty amps have. I remember seeing Rick Nielson in Fuse using Sound Citys in Rockford Ill in the 70's and being floored with the punchy mids he got.

[selloutrr]

Sound City / Dallas Orbiter were the reason we have hiwatt's. The mids are great and a very useable EQ. But i think we need to give some of the credit to the Partridge transformers. Much like A Drake tranny in a marshall can really bring them to life. but yes it's a thought if you wanted to use an active EQ

[jbrew73]

look at some of the ampeg models like the V4 V9 and SVT.

[FUCHSAUDIO]

look at some of the ampeg models like the V4 V9 and SVT.

Thats a good active midrange circuit and it's self-contained (it only does the midrange stuff . Meaning: you can keep your other tone stacks in service. Other than getting the inductor (ampeg replacement part ?) , should be eay enough to make.

[selloutrr]

search ampeg parts on google
www.fliptops.net
this is a great website dedicated to everything ampeg for parts. It's quick shipping and if you dont see what you need just ask 9 out of ten times he has it!