Stratoblaster for bass. Just this one cap change or two?

[BillyJ]

I am making a Stratoblaster booster for my Bass friend.
I know I can increase the output cap to add some bass but should I consider changing the value of the 10 uF cap from lug 2 of the gain pot to ground? Seems I might but figured I'd ask.
Just for note I am using JD's improved design here:
http://www.generalguitargadgets.com/v2/diagrams/asb_sc_i.gif

[aron]

Change the output cap to 10uF or larger 47uF? Then you can try it and if necessary, try a 47uF on the cap to ground as well.

[Mark Hammer]

There are limits to what such cap changes can accomplish.  In most instances, unless there is a deliberate reason to restrict bandwidth (e.g., the Tube Screamer), most designs will use a lower-bandwidth limiting cap value that keeps out stuff below maybe 40hz or so so that by the time you reach DC it is nicely blocked.  In any given design, increasing the value of such cap may allow a bit more bass to come through, but at a certain point, the bass is about as "unblocked" as it can be and adding more capacitance won't increase bass, and may even put device functioning at risk by not blocking DC fluctuations enough.

I haven't looked at this circuit or know enough about the relevant calculations to know whether it falls in the bandwidth restricted or bandwidth-unrestricted category, but try it as is first. There may well be enough low end  for everyone's liking in the stock circuit.

[BillyJ]

Yeah actually the stock circuit is what gave us the idea.
He tried and dug it a lot.
I had just opened my big mouth about being able to give it more bass so now I am gonna try to make good.
I am not sure what you mean by reaching DC....is there a way to damage say his more valuable than my life amplifier?
I know there can be a risk to speakers if I haven't misread some previous post about this kinda thing and we are ready t take it slow and easy there...
Could I prod you into expaining this more or perhaps just answering the question...when you say,

put device functioning at risk

by device you mena the effect circuit? Or is there more to it?

Thanks a million!
I do not want to risk my bros gear at all.....He's a big mutha! ;O)

[Mark Hammer]

I didn't mean to imply that equipment would be damaged, but rather that it wouldn't function as well as it might.  E.g., a Tube Screamer has enough DC-blocking caps along the way that monkeying around at the front end still would not result in DC coming out the jack and into something else that couldn't take it.  At the same time, that stray DC may bugger up how other parts of the circuit work.  That's all I meant to say.

[petemoore]

To the existing cap [for experimentation] using another cap [probably smaller value added in parallel to the existing cap using small alligators or test leads [try different values] to find where the extra bass allowance benifits meets no added benifit/adverse effect...then you could hard wire the chosen added value or add a switch for normal/added bass.
 be sure to match polarization of the polarized cap
 My exp with adding a paralleled incap has been that a much smaller value [say you're starting with a .01uf] adds alot of bass [say .oo47uf]
 This is one way to experiment with values without having to remove the existing caps [if you have enough various values, and types of caps..and that you can 'insert' the connection where necessary.

[moosapotamus]

Check out the LBP-1 and the EH Mole bass booster (Hog's Foot). The Mole is basically a LBP-1 that's been modified to boost more bass.
http://www.muzique.com/schem/index.html

The LBP-1 is similar to the Stratoblaster (might give you some ideas) and also sounds similar to the Stratoblaster. The Hog's Foot/Mole boosts low bass freqs. Theres a clip of the Mole on my web site.

~ Charlie

[Rob Strand]

It should work OK as is.

If you want to tune-in the fartyness when the control is max'ed out then you could play around with the 10uF cap - I'd start at 10uF and probably keep in the 0.47uF to 10uF region.

The output cap value is fine.

[BillyJ]

I put a 10uF going out and only brought up the 'pot cap' to a 1.5.
I will probably tell him to let me make him a hog's foot as I think he will really like that. Thanks Charlie. I had thought of taking a peek but didn't. Thanks for the prod :O)
Besides I have grown kinda fond of it even though I have one already.
I need to build an LPB too having heard about them so many times.
Uh what does LPB stand for anyay again?
Hmmmmand unless I am misktaken I could use the same baic layout for both an LPB and a Hog/Mole Foot.......?
Looks like he will be getting a moles foot and I will get an LPB in one shot...nice. Big thanks everyone!!