Clean boost or tube screamer

[gutsofgold]

I clipped one of the diodes in my tube screamer and it sounded PERFECT with my amp. Just the right amount of distortion I was looking for, sounded much more alive and upfront compared to the stock screamer. I still need my tube screamer for other times so I'd like to build something that has a similar sound. Would a booster sound like a tube screamer with only one diode? I'd assume that is essentially what I made when I took away one of the diodes.

Would the Micro Amp build be close? If not, got any recommendations for me? Thanks!

[ianmgull]

You can easily  get a on-off-on switch and select between two sets of clipping diodes, and no diodes when in the off position. Thats what I did with my TS and it sounds great. Or were you wanting separate boxes?

[petemoore]

If not, got any recommendations for me? Thanks!
  Jfet
  Jfets
  Omega
  I get the idea you like the sound of your amp when more signal hits the input, touch of assymetry or light clipping...hard to tell what your TS is doing...where the gain is set, how hot the guitar pickup/volume set etc.
  That's moot after you hit the input with a bit of transistor boost, BJT...anything...all different flavors.
  Not much of a TS fan, I just like the way other peoples TS's sound sometimes, and go for that tone using...DynaComp, BJT boost, Omega, Supreaux, Minibooster.
  Usually not all 5 at same time...
  The ones with 1 transistor are 'trebly, Supreaux can get gainy [especially if input is 'hit' w/gained up signal], they all have at least a touch of LP filter, and the Minibooster has a TC which generally does a good bit of LP filtering. TS like?...can be sorta I suppose. Do I think I want a TS in there?...not really. 
 

[gutsofgold]

I dont really want a treble booster, just a ... booster. Its hard to say what exactly my TS sounds like with just one diode (silicon), it definitely had the midrange scoop sound but the bass was still very present.

[cheeb]

You can easily  get a on-off-on switch and select between two sets of clipping diodes, and no diodes when in the off position. Thats what I did with my TS and it sounds great. Or were you wanting separate boxes?

+1.
If you like the way your TS sounds now, then you should just put in a switch so you have that sound, and then flick! you have stock sound for those times you need it. Sounds much better, cheaper, faster, and more space-efficient than anything else.

On the other hand, I ALWAYS recommend the NPN Beginner Boost. I love tat thing. Depending on your amp, guitar, etc. it may be able to get you there. But I would prob stick with the clipping switch.

[R.G.]

I dont really want a treble booster, just a ... booster. Its hard to say what exactly my TS sounds like with just one diode (silicon), it definitely had the midrange scoop sound but the bass was still very present.

Hmmm... remember that the TS is (in)famous for its midrange honk and "nasal" sound, not a midrange scoop. The way it sounds to you is the way it sounds to you, but that's not how everyone else hears it, it appears.

In more standard terms, the TS with one diode clipped will be giving you full opamp clipping on one half cycle, diode clipping on the other. The signal will be much bigger and heavily asymmetrical. This is not the same as what a simple booster would do. But then, you like the effect on your amp, which is the unknown value in the booster sound equation. People talk about booster sounds incessantly without even considering that their amp is half of the equation, maybe more.

Given that, I'd say that there's a lot of work to do to establish a common language of tone description before you and the people talking to you understand the same thing by the words being used.

[Gus]

You might like this circuit

http://www.diystompboxes.com/pedals/gusOverdrive.gif

A boost with EQ.   

[Mark Hammer]

Ditto on the confusion between boosters and overdrives and other things.  For me, a booster does two things: 1) optimizes signal amplitude to take advantage of whatever clean headroom is available, and 2) permits the user to alternate between two amplitude levels such as one for rhythm and one for solos.  Now, since the latter can also be a function of things like the pot-in-a-box that some have marketed, I suppose there is some overlap between what I call boosters, and those things too.

The extent to which the clipping diodes will exert their effect in a Tube Screamer topology is a function of the extent to which the diodes present a direct path between the output and inverting input.  If one inserts a resistance between those diodes and inverting input, then their action will be reduced.  In other words, there are intermediate values between having the diode in circuit and lifting it.

I put together a TS-808 clone with a variable resistance between one of the diodes and the inverting input; essentially one variant of the "warp" control that Jack Orman has elaborated so nicely at his AMZ site.  The pedal is now in the hands of one of my region's better blues players, who loves it and has replaced the vintage TS-9 on his pedalboard with it.  The extra pot allows for injecting variable amounts of asymmetry by reducing the effect of one diode.  As is always the case with such things, you can't really hear the difference it makes until you dig in and create notes where one half-cycle is clipped to a level significantly (or rather, audibly) below that of the other half-cycle.  At that point, the impression created is one of greater volume and dynamics.

Does such a control have to be unilateral?  Not at all.  Take a 50k log pot and wire it up as a variable resistor in series with both diodes (between the diodes and the inverting input pin).  This will allow you to adjust the overall amount of clipping action from harder to softer.  At minimum resistance, it is your stock TS-9/808.  At maximum series resistance, the pedal should function much more like a straight booster, with minimal coloration unless you feed it a signal which is hot to begin with. 

Note that this will NOT introduce asymmetry, but that's fine.  People seem to mistake the added dynamics and volume of what they call asymmetry as somehow stemming from asymmetry itself.  Undoubtedly, use of an asymmetrical diode arrangement will introduce a somewhat different complement of harmonics, but my sense is that their attention is principally drawn to other things, and much less to whatever harmonic content changes might be there.  The mod I describe will give you the added dynamics and volume in the complete and total absence of asymmetry.  Worth doing the experiment just to disabuse yourself of what it is you THINK is going on with asymmetrical diode arrangements.

[Gus]

Mark you might want to try the circuit I linked

Bootstrapped input
gain ~= X4.7 till EQ boost caused by the resistor and cap in the emitter leg to just about a gain of X 9.4
Output low pass (works better into a 1 meg or so tube preamp input R)
a boost and a mid boost and high end roll off to remove harshness.
work out the RCs
PLUS the added distortion of the one transistor gain stage, try different transistor most should all bias up fine.   If you have a scope and a signal generator feed triangle waves into different gain circuits and see what happens

How many have built this and liked or disliked it?

[gutsofgold]

I guess I want a booster that has a little overdrive, thats what I am getting at!

How would one describe the Rangemaster vs. the Microamp ??

[petemoore]

How would one describe the Rangemaster.
  Cleans up and guitar volume [when connected to RM input] works like gain control, requires 'the Germanium transistor for best results, but a Ge will generally make it work. How it sounds depends on [to a larger degree that most boosters] what it is plugged into it // what it is plugged in to [such as dark sounding, cleanish tube amp].
vs. the Microamp ??
  Has the 'advantages' of an opamp, and is a cleanish boost.

[DougH]

Mark you might want to try the circuit I linked

Bootstrapped input
gain ~= X4.7 till EQ boost caused by the resistor and cap in the emitter leg to just about a gain of X 9.4
Output low pass (works better into a 1 meg or so tube preamp input R)
a boost and a mid boost and high end roll off to remove harshness.
work out the RCs
PLUS the added distortion of the one transistor gain stage, try different transistor most should all bias up fine.   If you have a scope and a signal generator feed triangle waves into different gain circuits and see what happens

How many have built this and liked or disliked it?

I breadboarded it and it sounded GREAT. Adds a nice resonance to the overall sound. With some amp dirt it sings nicely- or string 2 of them together for more gain. It's a booster- it's an overdrive - sounds like what the OP wanted (to me).

[Mark Hammer]

Also looks like it would be a nice candidate for ther SWTC, using a 10k pot plus 470R fixed resistor instead of the 10k series resistor on the output.  I'll try and find some time later this week to make one, since it basically looks like an hour's worth of perfing and wiring, if that.

I think the critical element that a lot of people can easily overlook is that a clean faithful amplification of the original signal is not necessarily what is needed for desirable overdrive of the amp's input stage.  You need some toneshaping in there, and sometimes even a little bit of coloration.  Again, remember that the harmonics generated by the amp are a function of the spectral content you feed it.

[slacker]

Gus's Overdrive is well worth building. Sounds great on it's own or like Doug said stick 2 of them in series or put something like the NPN boost in front for a bit more grit.