how useful will breadboarding be?

[sedstar]

I am looking into trying to build a simple mixer powered by 9v battery. wimpy preamp, slight variation of standard Bandauxall low/mid/hi tone controls, and l/r pan pots. seems like a simple amp on the bus to acount for losses at summed and mixed output.

How well would this lend itself to a breadboard for a test assembly? I thought there were issues as freq's rise and audio stuff in general related to wires or something.

I managed to get 1:1 images out of my free schematic/pcb layout software, and realized my soldering ability is not likely up to snuff for such a small, dense, packing of componentry. I was thinking either making it a tad bigger and more spread out, bigger traces and more room, or, simply going from breadboard to perfboard and doing point to point.

I'm more comfortable with point to point, and if i recall from my RF days, i should use decent quality stranded wire for signal point to point?

 

[Viitalahde]

It will work just fine as a breadboard & general rats nest. :thumb:

 

[Scodiddly]

No problem doing perfboard or breadboard - I do it all the time.

 

[bcarso]

At higher frequencies, and sometimes in audio designs with a lot of gain-bandwidth, you may find the groundplane + pad-per-hole material from Twin Industries to be helpful. It's by far my favorite for anything except super slow noncritical work. Get the material with one plane only, or shorts are difficult to avoid. Use the ground plane side as the component side (a few parts can be tacked in on the other side in a pinch). Also be careful about cracked end caps on resistors shorting out to the ground plane---I had a tech who loved to cinch down each part with remarkable violence, I think in partial compensation for his nominally placid and ascetic outward demeanor. Needless to say his stuff frequently didn't work.

I also like solid bus wire and teflon tubing where needed, when the component leads themselves won't make it. The tubing doesn't easily scorch or melt, and if it does you get toxic fumes as admonitory feedback :razz:

 

[PRR]

Perfboard or even push-in experimenter breadboard will be fine, if you keep it neat. I've seen elaborate "permanent" P2P boxes that had to be re-built because they were NOT neat, high gain wires running hither and yon mixed with speaker leads.

bcarso has worked on much hotter rigs than a 9V TL072 mixer, and gotten in trouble, so he's not wrong, just working on other things.

> decent quality stranded wire for signal point to point?

These days, the wires from CAT5 solid network cable are the way to go. You can not beat the price, and you may get 8 different colors. Stranding is a real pain, and not necessary except under severe vibration or nightly set-up/take-down. On runs longer than a breadboard, I might listen to golden-ear claims of sonic superiority for 29/7 silver-plated MagikWire, but on a small breadboard it won't matter.

 

[sedstar]

okay, so bear with me, any electronics i did before this was all digital and microcontroller/microprocessor based. I am not "analog boy", lmao.

in general, i want all leads, component to component, to ideally be component lead to component lead, and any wires run point to point to be kept as short as possible. Just like real estate, the idea will be "location, location, location...", eh?

POWER leads, though even only 9vdc, should preferably where possible kept physically apart from signal wires, and signal wires kept as short as possible.

if possible, where i cannot help crossing wires, i shuold at least try not to run wires parallel, to avoid crosstalk. I shoudl think particularly in feedback from output of op amp back to input is where this minimal crosstalk induction would be most critical. a 90 degree crossing would be more preferable.

BUS WIRE... so when we talk of a BUS, in a mixer, the final bus...that should be made of bus wire? I did not know that. and shielding is made for it. cool. I assume this shielding has a ground? so that any stray crosstalk that reaches it will get dragged to ground.

I realize the circuit is not that high quality of a sonic project, I just want to try to adopt general good practice to get me started correctly, so when i tackle a bigger project, i wont screw things up.

beadboarding this thing fitst will be great. No pressure when breadboarding. that willlend itself well to perfboarding. if after all that things go well, i will consider makign real PCBs.

Oh well, i have been wanting to do this for a long time, no time like the present. I have wanted a damn 'scope for a while, but could never justify it, now decent used tektronix would be a great thing. Once i am done, i can physically LOOK at signals, and that will let me follow the signal around, thru an op amp stage, before, out, and feedback to see whats going on. I need practical circuit knowledge, that would likely be the best way to get it.

at least i know what to ask for x-mas now, hee hee. "Honey...let me make an order up for MOUSER, you have been asking what i wanted..." lmao...

Thanks guys...you take a bit of mystery and "awe" out of all this. I live in a small area, and its pretty rare to run into anyone that works at any level with electronics...theres a few parts solderers around, but...they just solder parts in on a line, they dont design or build projects or anything. Every now and again i runinto an "old school" HAM that built his own rigs, and its like a little slice of heaven.

sadly, any EE i ever run into, wont "talk shop"...I get that line about "I do it all day at work, i dont wanna talk about it", lmao. I always respond "sorry dude...sorry you hate youre lifes work so much" hee hee.