Doug Hammonds Tone Source (Brown Source Clone) - Vero needs varifying

[ulysses]

hey guys

doug uploaded the schem of his version of the brown source today. you can check the schem at http://aronnelson.com/gallery/Dougs-Stuff

i am pretty keen to give this one a go usually i would redraw the schem and convert it to a pcb.. but i thought if it was on vero then more people could give it a go.

so i loaded up DIY Layout Creator and gave vero a go for the first time. being that its my first attempt at designing a vero layout i would appreciate anyone with any vero experience having a look over it. i am used to pcb software that can check connections for you.



does anyone know how to re-order the parts list in DIY Layout Creator?

i should also note that i couldnt figure out how to get DIY Layout Creator to show the polarity of the electro caps. i had to mod it in photoshop. does anyone know how to do it in DIY Layout Creator?

cheers
ulysses

[Doug_H]

Thanks for your interest.

I don't have time to verify your layout (and vero gives me a headache to look at anyway ) but thanks for providing it. I'm sure someone will take a crack at it sooner or later.

I've temporarily misplaced my camera. Whenever I locate it I'll upload a photo or two. I'll try to upload a couple soundclips too.

This thing was a major PITA to finish. For the past few years I've had darn near a 100% success rate with my builds firing up the first time. But I spent a week getting this one going, with 7 or 8 problems after I finished it (the first time)- from wiring errors to weirdness due to the box I used (better explained with a photo). All of my gremlins saved it up and waited for this build...

But it works well now as drawn on the schem.

EDIT: Forgot to mention- one of the more interesting things I discovered about this was the "underfiltered" Vr rail which softened up the highs *when* the 3.9k in the tone control was "grounded" to Vr. With 22u or 47u it was too harsh. At first my engineering instincts told me that had to be a mistake- then when I heard the difference I believed the 4.7u was intentional in the BrownSource schems (on which this was based).
.

[ulysses]

hey guys

i went ahead and built it myself.. i couldnt wait for someone to take the verify bait

its all good news. the vero works perfectly and the sound is amazing. i love it.

doug, thank you, its awesome. time to put all those other overdrives in the bin

i updated the vero layout slightly with C11 moved slightly left so it fits in easier. i also tidied up the additional info, ie: pot values.

the only problem with this vero is that some of the larger caps are a bit big for the spaces and you will need to bend the pins to get them to fit into the allocated holes apart from that, its all good. i really should have thought about the size of the caps when laying it out. oh well.





as you will see from the image of the build i put in cradles for the caps that have the main effect on tone. but doug chose well, im going to leave them as is.

i also tried it with 1N34A diodes (in the picture) and i thought it was a bit warmer and less brittle the 1N4148s are still very nice though. maybe a switching mod??

will post some sound clips as soon as i have time (and the wife is out of the house).

ebay sellers - start your photocopiers!

cheers
ulysses

[MartyMart]

That's a nice layout and thanks Doug for the modifications, sorry that you had a
tough time with the build !
To get things even tighter, you can run pin 4's ground and pin 8's 9v jumper's
under the chip, I quite often do that, also a reversed protection diode could
easily fit bottom right from 9v to ground.
It probably makes no difference, but I put my 1M pulldown resistors as close
to board "input" as poss, you could move R9 left three holes to achieve this.

MM.

[Doug_H]

Okay, I added Ulysses's layout to my folder in the layout gallery.

Ulysses, thanks for designing the layout and building it. I'm glad you like the sound. I find it works real well as an "amp helper", much like the Rangemaster. IOW, I dial up a little dirt on the amp and then use this to add compression, sustain, singing harmonics, etc. It really focuses the tone in a good way too. Did you like the "twank" setting? Depending on where you set the tone, it can go from "stonesy" to "pagey" with just the bridge pup in that setting. With the volume at 50% it seems about unity gain but if you turn that up it will boost the amp and you can get quite a roar too.

The only "mods" I made was I eliminated the input buffer, corrected the output stage (based on earlier schems), and added the "twank" thing. I didn't get much out of the "tone control bypass" setting and discovered the twank thing by accident. That allowed one less switch pole too, even though I am using a 6P4T, so  it doesn't make much difference in my case.

[WGTP]

It's interesting that the gain pot and resistor to ground are so small, 25K and 220 ohm compared to the standard TS 500K and 4.7K to ground.  Does that seem to effect the clipping any?   

[John Lyons]

So was the sound night and day differernt from what you had before with the Nelson PDF?
Mine sounds pretty good with the fix on the chip output ( connected directly to pin 1) But if there is a big difference that would be cool...
The original tone switch selector is pretty lame as Doug mentioned...

I cooled of on the Brown Source and got sidetracked by a few other builds but I should get around to it since I already build a custom box for it!

John

[Doug_H]

Switch positions 1-3 sound pretty much the same as the BS. With the tone control turned up ~75% and higher I can hear pretty significant differences in bass response with those positions.

[Doug_H]

It's interesting that the gain pot and resistor to ground are so small, 25K and 220 ohm compared to the standard TS 500K and 4.7K to ground.  Does that seem to effect the clipping any?   

I don't know why they picked 25k and 220. Maybe it's for lower noise, who knows. That should give a gain of around ~40db in the passband, but because of the way it is filtered (with the 33n) it is attenuated to around 20-25db IIRC. Typically, if I wanted 20db I would use a 2.2k instead of the 220 and use something smaller than the 33n. I tried that though (compensating the 470n for the 2.2k) and it sounded different, not as "smooth". I don't know if the LT BS method was a happy accident or intentional. Maybe attenuating the passband changes the EQ shape in a way that sounds smoother.

[WGTP]

Hmmm,  the 33n cap is pretty large and the shunt to ground circuit rolls off around 14K if my calculations are correct, so the high and low roll off cross.  The higher the gain, the more the highs are rolled off, down to 100Hz at the pot max.  Hmmm interesting tone shaping.  It also looks like a lot of the signal is going to go around the diodes.  Notice the diodes also go thru the 1K resistor. 

How does it sound without the tone control?   

[Doug_H]

IMO the fun sounds are in the combination of the tone control and rotary switch settings. When the tone control was bypassed it had more gain but sounded bleh to me, no big deal. I have other high gain boxes that sound better. This circuit is not "high gain" by itself, but combined with a little amp gain it sounds real nice.

[ulysses]

hey marty

thanks for the compliments. im happy with the way it turned out. to be honest it was a lot easier than i thought it was going to be. it took me about 3 hours which wasnt to bad for a first attempt i thought.. problems arose becasue i started it after midnight it got to the point where trying to think 2 moves in reverse and three ahead from there.. it was getting difficult to keep track.. my brain was starting to shut down. i finished it and then kept going over it trying to remember if there were any moves i reversed without putting back in.. lol.. so i posted it hoping someone with a fresh brain would check it while i slept. anyway, in the morning a rechecked it and it all looked good so i built it and it fired up perfectly first go.

i dont really like people putting the opamp ground and Vcc+ under the opamp. i guess its just a bit messy with a cradle over the top. i did think about it at the time and decided to stretch it out to 22 wide to keep it clean.

i use an official boss wall wart so i didnt think about reverese protx. i guess i should have. people can stick one in easily as you mentioned if they want to. i dont get understand why people think they can stick their spair wall warts from old appliances (SEGA MASTERSYSTEM) into their pedals.. lol.. i once went to a job (im a wan tech by trade) to see why a voip phone was not working. someone has stuck a 200mA mobile phone charger into a 1A voip phone and couldnt figure out why it wouldnt get a dial tone.. 200mA was just enough it seems to make the welcome message display on the screen but nothing else.

john,

the difference between the one i built previously (the one we discussed in a previous thread) and this one is like night and day. i was surprised when you said my original mp3 sounded like yours as i thought your mp3's sounded right and mine sounded really bad. i had an opamp biasing problem that i couldnt get to the bottom of. i went over the board 100 times. everything looked right. prob a nackered part. the opamp was crackling in a really bad way.

in all honesty i think yours sounded good and im not sure you will be any happier with this one compared with the one you built (you did the mod that fixed the output pin right?). doug has modded the "no tone" selection on the rotary to include a nice additional tone setting. for me there were to many unknowns with the previous brownsource schems (i must have built 3 or 4, lol). its nice to have one that is verified to work properly.

check out dougs mp3 sample on his layout page. dougs demo gives you a good idea of the the sound of the peal over an already distorted amp. ill do my demos soon hopefully. i like to keep my marshall clean with pedals to push it into overdrive.

doug,

i like the twank. what i really like about this pedal is the ability to turn the tone right down and get a thick warm brown tone that has a hell of a lot of life in it. so many overdrives/distortion pedals are geared toward the high end screech like the TS, that when you turn down the tone they become tone-less.

out of interest doug, did you come up with any other cool tones/sounds during experimentation with parts?

cheers
ulysses

[John Lyons]

Ulysses

I'm going to redo mine anyway. I made a custom box for it already and the tone selector bugs me that hardly does anything waranting the panel space. The low tone settings are my favorite, seems like the high tone settings are mainly just bass roll offs. still nice to have a a treble boosted sound for a dark amp.
It will be nice to have closure for this one!

Thanks Doug and Ulysses...  I bet everyone else up to this point was saying " screw this one"..until they here dougs clip! Nice!

John

[Doug_H]

The low tone settings are my favorite, seems like the high tone settings are mainly just bass roll offs. still nice to have a a treble boosted sound for a dark amp.

Yeah, that's what the rotary switch is for. Turn the tone up to get clarity, then use the switch to thicken it up if desired. I have to darken up this amp some for high gain sounds (one of its quirks) and this pedal sounds real good that way. With the tone at 75% or above and switch in position "1" it sounds a little like a Rangemaster. I usually prefer to set the switch to "2" as that gives it a little more bottom. "3" can get very thick.

[ulysses]

hey john

if you are going to remake it you may as well give my vero a go its a smaller board than the old incorrect pcb of nelsons

still no time to make demos unfortunatly. hopefully soon.

cheers
ulysses

[John Lyons]

Ulysses

I'm going to do a PCB of it. I don't really dig vero ( to be honest I never have used it though...) I have a pile of copper clad board here and I like to make PCB layouts. I'll post my PCB and layout when I get it finished for others, If they aren't scared away by all other bunk builds in the past of this one.
The layout of nelson's is probably like the original in that it uses the pots and switch on the board. That's why the layout is so big. The switch is a big boy!

I may refer to the vero layout for placement though.

Thanks

John

[Serge]

This is my next build.  What kind of pots did you use (log/lin)?

[ulysses]

This is my next build.  What kind of pots did you use (log/lin)?

this is what i used

level pot - 10k log (b)
gain pot - 25k log (b)
tone pot - 100k lin (a)

cheers
ulysses