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Vintage threads from the first ten years

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6/11/1999 1:55 PM
Hi all,  
I just wanted to tell y'all that I'm finished with my  
Dumble overdrive-clone and that I'm going to have a nice  
weekend test-driving it.  
Hope you'll have one too.  
6/11/1999 2:39 PM
I'm sure everyone here will be looking forward to your test drive results.  
Good luck,  
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6/12/1999 2:52 AM

I'd be interested in hearing more about your project. I've very close to finishing mine--it's up and running and sounding great but gonna try a couple of things I omitted.  
How about some construction details?  
Enjoy it, I'm enjoying mine  
6/14/1999 8:05 AM
I omitted the osc. stopper-caps but had to include them  
since I did get some ringing. Dual bias controls, one for each tube. All pots are available on the front. I also put a cap in the PI (to ground) I don't know if there should be one, there wasn't any in the drawing, besides the dual bias, the cap in the PI and the jazz switch it is as the schematic.  
6/14/1999 11:02 AM
Nils, Thanks for the reply  
I also included the .1uF cap in the PI. In all the pictures of the guts of Dumbles I saw one there--kinda thought there had to be one there actually.  
How'd it sound? I heard it was suppose to be dark sounding but found mine too bright. I had added a 500pF in the tone stack instead of the 330pF. I dropped it to a 250, no bright switch connected yet and it seemed to really work out for me.  
I also had the ringing, I forgot those caps in the OD section I'm assuming also. Haven't added them since I haven't had time. But with the input to the OD right below the threshold of the ringing it was a very smooth, pleasant overdrive that sounded fantastic. I am running a 5751 in the OD slot.  
What did you do for the driver tube--I ended up with a 12AT7 in mine. Again haven't had time to experiment but with what I heard I don't think I have too much to do.  
Sorry about the questions--very curious about others builds  
6/22/1999 12:12 PM

If I remember right (have to check this) I put in a .01uF cap, and I didn't have a 330pF at home so I used a 250pF instead, I do have the bright and deep switch.  
I also like the smooth overdrive this amp produces it's like butter, unfortunately I don't have any real vintage experience to compare but I do have the Chieftain-clone and I think they compliment each other.  
I'm going to have a friend of mine (he's a semi-pro) try them both and write down his comments.  
I've built mine in a Fender 75 chassis, that I earlier had tried to modify with no luck. I'm using 12AX7 (Mullards) in all three positions and some newer 6L6 labelled RCA and I was thinking 5881.  
Anyway, I really do recommend cloning this amp, I use this and the Chieftain on my gigs and certainly have no need in spending thousands of dollars.  
I've named mine to FUMBLE due to those stupid  
"3 o'clock in the morning mistakes".  
Well this became long, but if anyone has questions...  
Thanks to all for the help  
6/22/1999 12:47 PM
Re: Dumble...Schematic Source?
Have been following your exploits with great interest. The one (main) question I have is where did you find a Dumble schematic to build your clone from?  
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