First 2007 project :D .........

[MartyMart]

..... will be the new ROG "Thor"
All parts are on veroboard, around 3inch by 1.5inch, just have to wire up pots
and jacks tomorrow ....... will report back then !

MM.

[MartyMart]

First off, aron .. I was able to lock and unlock this topic  !!  ??
Wanted to modify the title but ...... 

OK, the R.O.G guys have done a stellar job on this circuit, which really sounds great, I have
about 15 or so "Jfet" amp type circuits and I'm a real fan of this method, regardless of the
"it's not an amp replacer" crowd - these are still VERY high quality and pleasing OD/Dist circuits !

I stuck with the recomended Jfets and a TL071 IC.
Only slight changes were the 22n's @ 18n 'cos I'm out of those and a 33k for the 39k to
the opamp + pin
Very good response to gtr vol roll back, cleaning up well, not "uber high gain" but the intention was for an
accurate gain range for this "amp sim" ( can I say that Jfet police ?? ) and I think they got
that about right.
The bright/Bottom switches work fine but I'd prefer this with a one knob TC really, so perhaps
something like a BMP/BSIAB control would work after the IC, use a dual and get a vol recovery
stage for free perhaps ?
Tone :
Good overall with a nice "chunky" mid sound to it and not too much "fizzy" highs at all.
Really nice for rhythm work and also lead work when dimed.
No noise or bias issues with the Fets that I choose right from the pack and I also had
a "works first time" build on vero ( I always like that )

Thanks chaps, this one is a definate "keeper" 
When I get some more time, I'll look at the TC options and post anything that works out
A TC would take this from a great circuit to a "superb" circuit and offer a bit more scope for
use with different amps etc.

Marty.

[MartyMart]

OK, I had a "brain fart" which seems to work !!
Look at the "bridgeT" network at the opamp, remove the 33k to ground between the pair
of 22n caps and break that connection.
Wire up a 22k lin pot, so that each outside lug connects to each of the 22n's and the wiper
connects to a 10k r to ground.
At one side you have about 33k and that decreases to around 10k at the other, wire it CW from
opamp "-" end 22n for the pot to work the right way round.
It has changed the tone slightly, but does give a decent top roll off, if anyone could offer a better
use of this, or better values, then please chime in.
I first tried a 100k pot with wiper direct to ground and got horrible "oscillation" whistle, so the
value was way too high and i guess the 10k limiting wiper "r' helps with this new method.

Thoughts ??

MM.

[phil]

..... will be the new ROG "Thor"
All parts are on veroboard, around 3inch by 1.5inch, just have to wire up pots
and jacks tomorrow ....... will report back then !

MM.

Hi MartyMart congrats on your build of the Thor! I'm glad you are happy with the effect -  I was trying to decide on building the Thor as well and your posts made the decision for me -This is going to me my first build of 2007 as well. Where did you get a Vero layout for it - or did you design that yourself?

[mydementia]

This was my first build of 2007 too!
I have low voltages on my opamp - so I must have a wiring problem somewhere...my vero skills have diminished greatly since I started making PCBs!!

Once I get this circuit sounding like it should - I plan to box it with my ZW44.  Should sound awesome pushed by the ZW...

Stay tuned...
Mike

[petemoore]

  Nice !
  "it's not an amp replacer" crowd - these are still VERY high quality and pleasing OD/Dist circuits !'
  I think it's a good thing they need tweeked !...lol those Jfets make or break the tone IMO, push a gainy one just so hard and WhonK...you get that 'thuddy too much' into/outta NTE458/J201 sound..tube amp like...lol, like the thuddy tube amp that needs 'something more or less' somewhere..
  What's cool is when the Jfet circuit gets tuned with nicely 'balanced gain stages' [swapping and biasing Jfet compliments] and the 'less spur like' qualities of the Jfet distortion get the smoother edged sound...sweetness!
  I'm not without tubes, but Jfets certainly can make 'this' amp sound alot more like 'that' amp.
 

[MartyMart]

Hi MartyMart congrats on your build of the Thor! I'm glad you are happy with the effect -  I was trying to decide on building the Thor as well and your posts made the decision for me -This is going to me my first build of 2007 as well. Where did you get a Vero layout for it - or did you design that yourself?

Did my own layout and kept it quite small by stacking Q1/Q2 above each other as with Q3/Q4.
have not drawn it up - that takes as much time as the build !!
A dual opamp may make it smaller, then you can wire up all on one side, and ignore the other.

This was my first build of 2007 too!
I have low voltages on my opamp - so I must have a wiring problem somewhere...my vero skills have diminished greatly since I started making PCBs!!

Once I get this circuit sounding like it should - I plan to box it with my ZW44.  Should sound awesome pushed by the ZW...

Stay tuned...
Mike

Should sound good, what are you're opamp problems ?
My TC mod sounds good, perhaps the ROG boys can suggest a better tweak !

MM

[mydementia]

I'm getting around 1.3V on the pins that should be 4.5V - thus, a splatty, ugly, underpowered opamp output sound.  I haven't had time to go back through the circuit... my holiday houseguests were not as excited about my soldering habit as I'd hoped...   I used the ROG PCB layout as my perf template and didn't sub any critical components (only had to approximate a couple resistor values).   I'm going to walk through my build with the schematic so I can figure out where I honked it up.

Mike 

[MartyMart]

It's probably your VB half voltage screwed somewhere, do you have 4.5v at the 10k pair junction ?
Or ... could be your 56k from VB "node" gone askew !

MM.

[phil]

Did my own layout and kept it quite small by stacking Q1/Q2 above each other as with Q3/Q4.
have not drawn it up - that takes as much time as the build !!

Ok thanks anyway - I don't have any experience creating Vero Layouts (or any layouts actually), but I just found a Perf Board Layout from Xavier so this will get me going ...

http://aronnelson.com/gallery/albums/Layouts/Thor.gif

[mydementia]

Bad solder/junction after the pair of 10k resistors - all fixed up...
Interesting circuit...at least the way mine turned out... my gain pot (used a 1MB since I have about 25 of them... 1MA's are in short supply in my bins...) seems to have a problem... At 'zero' - no sound passes (makes sense) - from about 9:00 to 3:00 (assuming zero is at 7 and max is at 5) I get weird misbiased tranny type of output - but when I get to or near 'max' I get strong signal - gated - but signal.  I must have more problems in there... I knew I shouldn't have been building while my mother was explaining why having children will make my life o-so complete - ick!

I'll keep poking at it... might try a different 1M pot and recheck the junctions around that area...
Mike

[MartyMart]

Bad solder/junction after the pair of 10k resistors - all fixed up...
Interesting circuit...at least the way mine turned out... my gain pot (used a 1MB since I have about 25 of them... 1MA's are in short supply in my bins...) seems to have a problem... At 'zero' - no sound passes (makes sense) - from about 9:00 to 3:00 (assuming zero is at 7 and max is at 5) I get weird misbiased tranny type of output - but when I get to or near 'max' I get strong signal - gated - but signal.  I must have more problems in there... I knew I shouldn't have been building while my mother was explaining why having children will make my life o-so complete - ick!

I'll keep poking at it... might try a different 1M pot and recheck the junctions around that area...
Mike

Mike, did you bias Q1 to 6.4v and Q2 to 4.5 ?

MM

[mydementia]

Yep - Q1 is at 6.42V and Q2 is at 4.51V...

[MartyMart]

Q3 drain should be battery voltage and Q4 (lower of the Mu pair) at about 1/2 batt voltage or just under.
If they are correct, then it must still be around the opamp where there's a problem.

On a side note Mike, i went back to the "Plexizer" and made Q1/Q2 2N5457's, with a re-bias
it's sounding real nice, perhaps not as high gain, but a better range now

MM.

[mydementia]

As I recall (at work now - can't check) my drains lined up just as you say... must be an opamp connection problem...

On a side note Mike, i went back to the "Plexizer" and made Q1/Q2 2N5457's, with a re-bias
it's sounding real nice, perhaps not as high gain, but a better range now

I'll have to try that - my Plexiser is sitting with six other boxed pedals next to my pedalboard...

My own side note...
I was diddling around last night with my latest multibox (Crank->ROG Supreaux->Mr MOStorto->BSIABII) and accidentally stomped on the Crank when I was playing through my Dr. Boogey - oh my... it adds a TON of highs to the dark Boogey tone... great for a searing lead tone!!  Not a lot of coloration - just a lot of treb.  I haven't tried the Crank in front of the Boogey...might be tonight's experiment...
Mike

[mydementia]

Well... I just built another Thor (tired of debugging the first one) - this time using Xavier's perf layout (http://www.diystompboxes.com/smfforum/index.php?topic=52621.20).  At first, I built it to 'print' - then I saw Gaussmarkov's comment (think he's right) so I cut the trace and added the jumper - didn't make much difference though...  I still get strange behavior with the gain pot... clean(ish) from 7-8 - squeel like a pig from 8-4 - huge gain from 4-5 (7=min, 5=max).  All my voltages look right and signal seems to flow... just not sure what's going on with the gain pot.  Yes, I tried two different gain pots (1MA's) - same result.  I also tried a few trannies in Q1.  No change...  interesting that I built the circuit from two layouts and have the same malfunction... grrr...
I haven't seen a bunch of positive build reports on this circuit yet... anyone else had success besides Marty and Pete? 
To be continued...

[John Lyons]

Mydementia

To make a linear pot have a taper similar to an audio/log pot just put a resistor between the wiper and ground lugs.
25% of the value of the pot gets you pretty close. So for a 1 meg pot 250K should do it.

I doubt that the circuit is to blame. Ther ROG guys are pretty savy from what I've seen. I don't think they would put out a half ass circuit.
Plus, if a couple people have working builds then it must be ok... It's probably something you are overlooking (usually is for me)

John

[Gary]

interesting that I built the circuit from two layouts and have the same malfunction... grrr...
I haven't seen a bunch of positive build reports on this circuit yet... anyone else had success besides Marty and Pete?

How many positive reports do you want to see?  Do you think we would post something that doesn't work?

I shouldn't let this kind of crap bother me, but you've caught me on a bad day.

Yes, we are screwing you.  This circuit is a piece of sh*t and will not work.  Don't bother building it or any other circuits for that matter.  Go get a broom handle with a nail in it and walk the sides of the road picking up cans.  That's what I'll be doing, since I can't give you a freebie that will put itself together for you.  Hell, just wait around a few weeks.  You'll be able to buy this design in a manufactured pedal for around 200 bills.  Ain't I right, W?

I can't understand how someone can deviate from the schematic, then cry and bitch about how they got screwed by a bad design.  I'm sick of seeing people bitch about free stuff that we spent countless hours working on.  Do you think we get paid for that?  I'd rather spend time with my family and I will now.  The other guys at runoffgroove don't have as short a fuse as I do.  I've had enough.  This was one of the reasons why I dropped off the radar for a couple of years in regards to pedals.

Let me help you out:
-Do you want me to mail you a dozen or so clips of the prototype in action?
-Did you measure your frickin' FETs?
-Do you want me to give you the exact measurements of the FETs I personally set the circuit up with?
-Do you want me to mail you those exact FETs?
-Hell, do you want me to mail you the prototype?
-For that matter, I'll ship you my brain, guitar, cables, amp and cabinet, too.

I am truly sorry I came up with the idea of updating the Thunderchief.  I am truly sorry I decided to get back into developing circuits for whiny babies like you.  With folks like you, it's always someone else's fault.  YOU couldn't have f*cked up, could YOU?  The 'groove team worked hours, days, weeks on this design and all you can do is cry like a little b*tch because you can't get it to work.  Send me your mail address, I'll send you the prototype.  You can stick it firmly up your ass.

I'm done with this crap.  You've seen the last pedal I will work on.  Who's sh*t will you cry about now?

I want to be clear I am not speaking on behalf of runoffgroove.  I am speaking on my own here.  I do not want any fallout form this to hit the guys at runoffgroove.  This is just Gary speaking.

I want to say thanks to everyone that built anything I worked on in the past.  I want to say thanks to everyone that gave me props.

I apologize to the others at runoffgroove for doing this.  I've had enough of this crap and cannot be professional about this subject anymore.  I'll be in touch personally to discuss this.  I'm very sorry, but this needs to be done.

Sorry for the typos/bad grammar, etc.  I'm very angry right now.

OK, crybabies!  You've got one less designer to bitch about now.  Sooner or later, you'll have to bitch about yourselves.

Peace out,
Gary

[mac]

Gary,

I breadborded ALL the fet circuits @ ROG. They ALL WORKED OK from the start. They ALL SOUND OK.
We can sit hours to discuss about if they are close to the real thing (there is a recent post here about fet simulation), but the main point is they are good sounding circuits. And let me add they are good instructional circuits for everyone.
I am tracing both channels of my Laney LC30 to make a fet replica. I've designed my own fet overdrive based on ROG's circuits which some day I'll post here.
So don't let the words of some newbies discourage you, I bet there are a lot of guys here that appreciate ROG's designs.

mac

[mydementia]

I didn't mean to imply that the Thor circuit was flawed - and I certainly didn't mean to offend anyone (Gary - PM sent). 
I greatly appreciate everything the ROG guys do - for free - for this community. 
I've built almost all of the JFET work-alikes from ROG and this forum with great success (a few took two builds...but they worked in the end). 
I must be doing something dumb in my Thor builds - hopefully I'll get it figured out in my troubleshooting thread.

Again - I apologize if I offended anyone.
ROG Rocks!
Mike

PS> Marty - sorry for derailing the thread - I just started my own.