Newbie Question - Whats the best valve type overdrive?

[simon111]

Hi Guys,
   A very general question here. After finishing my Negative Ground RM I am looking at building something a bit more complex. I have been looking at the valve emulation type circuits over at ROG. Which one do you like best? And there any other valve sounding distortion pedals around? CD4049 (?) I must admit here I am a bit of a Queen nut so the English channel looks promising.
I was thinking about trying to build the Odie, as it seems to have a nice amount of gain from the sound clips (and farily simple). But wanted to hear your views on alternatives before I begin building it.
Thanks

Simon111

[bass_econo]

Just search around on the forum.  There are always lots of soundclips and discussions on ROG builds...

A couple Odie soundclips recently posted here -
http://www.diystompboxes.com/smfforum/index.php?topic=43544.0

[mac]

Why not all the valve emulatons circuits at ROG? They are very simple and low cost. You can breadboard them and choose the ones to build.
Why emulation? There are some good and simply circuits with an opamp driving a real tube. Or use a RM instead of the opamp to drive a valve.

mac

[petemoore]

Hi Guys,
   A very general question here.
  >>To a very application specific question.
  >Adding circuit chain info starting from the speaker and following through the amp, other effects and pickup type allows much more specific information by which to formulate a more specific answer.
  After finishing my Negative Ground RM I am looking at building something a bit more complex.
  >>Tha'ts cool, I like the RM, and have read widely varying [from 'blechh' to 'kills'] build and even application reports on the circuit. What is your experience with it [likes dislikes] ?.
   I have been looking at the valve emulation type circuits over at ROG. Which one do you like best?
  >>Best is a word...not a bad word, but a word frowned upon for use reporting comparison/differences in circuits, because 'best' inherently implies [or insinuates] there is a 'worse'...or 'all others are less than' inference.
  >Because these all use Jfets' they are comparable, how well these emulate the actual amp circuits the Jfets copy the tube functions in is a 'well threaded' topic, plenty of info in past here, search/click should dig up lots of that.
  And there any other valve sounding distortion pedals around? CD4049 (?) I must admit here I am a bit of a Queen nut so the English channel looks promising.
  >>I'm of the opinion that these circuits may or may not get you closer to the 'Queen Nut' tones you desire. You could also consider building 'it' in stages, ie start with a 'stage' lifted from an amp circuit, or say Jfet Stratoblaster or Minibooster [these latter Cct.s mentioned, I find are a great circuit fragment and 'couple' well with later stages to produce distortion, then breadboarding [I just perf the stuff and use what I like, generally socketting here and there, socketted transistors at least, especially for Jfets]...this of course would take times to do, and would be a lengthy project, but you'd gather alot of experience and get Lots of Tweek-kreds in doing so.
  >That said...pick some circuits and build them stock...try 'em out. There really is no substitute for inserting a circuit into YouR chain and dialing Your guitar / amp /etc. to see what tones you can get that you like, also what new tones you may 'learn from'...ie circuits have been known to expand and develop playing styles and techniques...just because they excel when performing in that style...
I was thinking about trying to build the Odie, as it seems to have a nice amount of gain from the sound clips (and farily simple). But wanted to hear your views on alternatives before I begin building it.
  I built an Odie, and it did a 'light' distortion, IIR and built it correctly.
  I found the Prof. Tweed, Supreaux [and other 'smaller' Jfet Ccts] to do nice Fender Amp type tones, and the more 'severe distortion' Jfet amp sims to...well I had problems getting one I could use...bias/noise/ or some other 'personal' problem [with my build]... none ever really made perma-pedalboard status....that's just me.
  It's all very subjective [to the point you may just have to build 'it' to see what 'it' does, exactly] and depends directly on your mind/ears/guitar/amp/speaker[s...
  More background on what the circuit will be insterted 'into' [your rig] might illicit more eloquent answers as to 'which one'.
  There are more Jfet Amp Sims, all you need is a tube amplifier schematic, a pen and paper, do a little reading at ROG as to copying outright the amp schematic [generally the preamps can be copied to good effect]...and Stick a Jfet
  Gate where Grid for tube
  Source where Cathode for tube
and Drain connections
  Swap Jfet for tube in 9vdc circuit [instead of 140vdc or whatever].
  Thanks

Simon111

[simon111]

Just spent the afternoon and evening building the thunderchief.
WOW! Not even in a box yet (so it does hum a bit)
So good on my little pathfinder amp. So gritty and overdriven.
It reacts so well to your picking.
And it worked first time!
(thats a first for me)
One little thing of note though. When I hold a note, generally a high note, it sustains OK for a few seconds (slight warbling) then goes into a nasty sounding decay. Is this usual or is it a bad component. Any thoughts.

But this thing ROCKS!

Simon111

[wampcat1]

Just spent the afternoon and evening building the thunderchief.
WOW! Not even in a box yet (so it does hum a bit)
So good on my little pathfinder amp. So gritty and overdriven.
It reacts so well to your picking.
And it worked first time!
(thats a first for me)
One little thing of note though. When I hold a note, generally a high note, it sustains OK for a few seconds (slight warbling) then goes into a nasty sounding decay. Is this usual or is it a bad component. Any thoughts.

But this thing ROCKS!

Simon111

Sounds like a bias thing. Try fiddling with the trim pots.

bw

[Ge_Whiz]

If you like Queen, then I can recommend two builds at ROG - the English Channel, and the May Queen. Both sound great.

[mac]

Just spent the afternoon and evening building the thunderchief.
WOW! Not even in a box yet (so it does hum a bit)
So good on my little pathfinder amp. So gritty and overdriven.
It reacts so well to your picking.
And it worked first time!
(thats a first for me)
One little thing of note though. When I hold a note, generally a high note, it sustains OK for a few seconds (slight warbling) then goes into a nasty sounding decay. Is this usual or is it a bad component. Any thoughts.

But this thing ROCKS!

Simon111

I had this problem when I did not have a wire to ground.

mac

[jmusser]

So far in my estimation anyway, the best ROG has to offer is the 3 Legged Dog. Tim Escobedo has a real nice and simple circuit over on his site, called CMOS Drive, that's also excellent. Mark Hammer has a couple real nice circuits over there on his site that I haven't built yet, that are based on the 4049. I would imagine they're both fire breathers. The 3 Legged Dog, and CMOS Drive both make a SS amp sing like a tube amp!

[uan]

Just spent the afternoon and evening building the thunderchief.
.....
......
One little thing of note though. When I hold a note, generally a high note, it sustains OK for a few seconds (slight warbling) then goes into a nasty sounding decay. Is this usual or is it a bad component. Any thoughts.

ahaa..! I built TC few days ago using 2N5484 and the same problem also happened to me(sustains only for a few secs then the sound gone). What i do, i changed the 470 ohm (that connected to 3rd transistor source) to 10k and rebias all. Its now sound better/normal but i'm still thinking with that kind of output the sustain should be more.. is there any way to increase the gain/sustain without swapping transistor? the 2n5458 is the only option i have in my place (south malaysia).

and yeah.. ThunderChief really rocks!