Onboard and SMD

[Zben3129]

Hi guys,

I was just wondering how hard smd components are to work with, as I am thinking about building my own guitar, and I thought today of putting a tube screamer and/or a compressor onboard. It would really be cool to have a push/pull pot control the tube screamer onboard, im just worrying about space and I know smd technology is a way to go to conserve space, I just dont know how workable it is

[gez]

As far as hand soldering goes: if you use the right iron (pencil type with fine tip), a pair of tweezers and a magnifier, then it's not so bad once you get the hang of things.  1206 surface mount components are the easiest to work with.  There's a fair bit in the archives re soldering techniques.  For example:

http://www.diystompboxes.com/smfforum/index.php?topic=53057.0

[Zben3129]

Oh so that part is possible! That just leaves, would putting a ts in a guitar be feasable?

[PerroGrande]

Yep -- DIY SMT is possible. 

Certain sizes and types of SMT lend themselves better to it than others.  For example, the SOIC-style op-amps aren't ridiculously difficult as long as you have the proper tools (tweezers, magnifier, small tip iron, steady hand, patience, and flux...).  There are some SMT styles that really need the appropriate equipment to work with, but most of the stuff we encounter in this arena is not of that variety.

On the other hand, depending on the amount of real-estate available inside the guitar, you might be able to fit a through-hole design in there.   This depends, of course, on the circuit board design and the selection of components.  For example, I have two flavors of 0.0022uF mylars -- one is gigantic while the other one is tiny.  The voltage ratings are the real difference in this case, but both fall well within the range of what is needed for a pedal.  The other issue, of course, is the real estate for the potentiometers, etc.  Through-hole electrolytics are space-eaters, too.  However, watch the voltages carefully on the SMT variety of electrolytics (a lot of them are rated at or around 5v).

[Zben3129]

Thanks for the Input! Im starting to belive this may be not only possible but plausible....

[Mark Hammer]

Possible and plausible, certainly.  Advisable?  That would depend.  There are some things I would unhesitatingly recommend as an on-board circuit.  For instance, a buffer is generally an excellent idea.  But a great many other things are often best done OFF the guitar rather than inside it.  My reasons?

• While there are nice click-open battery compartments you can get now that don't require unscrewing a pickguard and risking damage to the guitar's finish, it is still a nuisance to have anything run off batteries in the guitar.  Running wallwart power to the instrument itself is a real PITA.  Some things require so little power that you'll likely be restringing several times, or changing vibrato bridges or pickups, before you need to change the battery again (e.g., a FET buffer), but some require much more than that.  If you have to remove the pickguard on a Strat or clone to change a battery twice or thrice a year, you WILL be asking yourself "What was I thinking?". (Note: some folks cleverly avoid that by placing batteries in the vibrato-springs area)
• DIY folks like to have the little extras that make an effect truly theirs, and this can include toggles and extra controls.  The circuit itself may be tiny, but it still requires panel space, something which is a very limited commodity on a guitar, even more limited if we're talking convenient location.  Changing an on-board circuit after it has been installed is a real PITA.
• The serial order of effects is frequently used to change the quality of their sound.  The textbook case is distortion into wah versus wah into distortion.  The moment you install an effect into the guitar itself, you have essentially forfeited any flexibility regarding where that effect goes in your signal chain.  There ARE ways to get around that, but they are so complicated and limiting as to render null and void any and all advantage gained by situating a circuit inside the guitar.

If you want a guitar that has THAT specific tone, and you can live with it comfortably (perhaps because you have other guitars that will permit you to use other effects in other ways), then go ahead.  But don't think that onboard circuitry, no matter how small, will be all champagne and roses.  There WILL be some things you forfeit, and obligations you undertake.  If this is your principal guitar, and you are NOT in an SRV tribute band, you may want to reconsider.

[Zben3129]

haha SRV tirbute...

Anyways, I am building my guitar, i would never do this to my SG 

So the reason i was thinking about this was because if i planned ahead, I could have a battery door on the back, non intrusive to anything else on the guitar making changing it a snap. Another thing i was thinking of was running 9vDC from a wall wart through the ground of the guitar cord should I ever want wallwart power. Finally, as I am designing the guitar, I could almost have an effects panel on the guitar maybe 2 or 3 effects on the guitar, with a rotary switch to determine order. I was thinking maybe ts 808, compressor, and maybe chorus or possibly my preamp.

[Mark Hammer]

It's not the dreamworld it's cracked up to be.

Can you play and step on a pedal at once?  Unless, God forbid, you have some physical shortcoming that prevents it, you probably can.  Can you pick AND change between chorus and no chorus, all at the same time?  Not bloody likely, unless you have very "economical" solos with a few seconds between notes.

Multiple effects on-board may sound cool at a conceptual level.  It's like you have all this......power.  But after a bit, it becomes like having a couple of really hot girlfriends....who all live overseas.  Not as thrilling as it sounds on paper.  Having the effects at one's disposal, and being able to use them the way you want are two different things.

You will note the quick painful demise of:
The Gretsch Super Chet
The Electra MPC line
The recent Danelectro on-board effects guitars (can't remember their name and could find no reference to them in any of the many Dano-related sites I visited)

[Zben3129]

haha i was thinking along the lines of variac but with effects