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previous: Steve A. Joe::replacing 500pF C2 wit... -- 2/7/1999 5:18 PM View Thread

Re: Vox Preamp Final(?) Schematic: Comments Welcome

2/7/1999 7:37 PM
Joe Fuzz
Re: Vox Preamp Final(?) Schematic: Comments Welcome
That will make a BIG difference in tone and signal levels- I don't know if you will be able to still call it a Vox preamp (it'd be more like an early Marshall...)  
I think your instincts are correct here. It probably stopped being a Vox preamp a couple of revs ago. :-)  
I went ahead and posted the latest rev I've got. Click here to see it. Note: since this gif is so wide, you may want to right-click on the link, then select Open in New Window from the resulting pop-up menu.  
How about a switch to toggle between the 2 values?  
Good idea. I've already drawn in a couple of extra pads on the PCB but I was just going to solder the cap in and out. The switch idea sounds much cleaner. However, there's such a *huge* difference betweeen the 2 values...  
You are referring to the post-cathode follower tone stack used on the tweed bassman/early Marshalls, and not the BF stack- right?  
I'm detecting a Marshall bias here! :-)  
Seriously, I picked this circuit up right off of the Tone Circuit Simulator software. (It's by Dave Signa. I can dig up a link if you need it.) Seemed to be much more expressive. Since I was changing the response curve with C2/C3 before the tone control by such a huge amount, I decided I needed a more versatile tone section. I like what I saw in the Tone Simulator on the Fender tone control the best.

jason Re: Vox Preamp Final (Atten. Steve A) -- 2/8/1999 6:54 AM
Steve A. Re: Vox Preamp Final(?) Schematic: Comments Welcome -- 2/10/1999 3:07 AM