Multi-effect Unit Tips/Suggestions??

[Styles]

Hello!

I've lurked these forums for quite a while now and finally registered, which i should have done loooong ago.  I'm a somewhat novice pedal builder and have about 20 some projects under my belt mostly for myself and friends.  Getting more comfortable all the time, and decided to go for broke with my next project...

I tour fairly often, and dragging around a suitcase of pedals, patch cords, and a twisted One Spot is a royal pain in the ass (and sometimes less than reliable).  So i thought, why not just hardwire a handful of pedals into one enclosure, with its own power supply built in?  Doesn't seem any more difficult that whippin out a few pedals in a row right?

Here's the plan:  Five Pedals- Overdrive (not sure yet) > Silicone Tone Bender > Torchy Phase 45/Vibe > Madbean CE2 > Rebote 2.5 Delay.  Live, I use two amps, a Classic 30 and a 5E3.  I want this unit to have a pedal out (duh (for classic 30 only)) and a dry out and always-on ZVEX SHO boost out to send to the tweed (want both options).  I was going to split the input with the AZM splitter.  There will be an FX loop w/ switching jacks to patch in a wah before the modulation stuff.

Not sure what to do about powering it- was either gonna dissect my onespot, or also found this guy at mouser:  http://www.mouser.com/ProductDetail/Cincon/CFM1009S/?qs=Pauzw2weiyOmph5KLTeP5ht4yvdgKxVU  a 9v ac/dc switching PSU.  I think this would work?

Is there any advice that ya'll could add?  Maybe a buffer after the pedals, grounding/power advice, etc? 

So glad I finally joined, these forums are great!

-Styles

[nocentelli]

I've often planned countless multi fx boxes, but never actually made one: I think part of the problem is that I find the job of wiring up the board, switch and pots such a chore the idea of doing it 4/5 within one pedal puts me off. The idea of one box with just OD, fuzz, delay and maybe one or two others, a single power in and only two or three connections still really appeals.

I guess if you want to run multiple outputs it's going to have to be buffered, for power I'd be tempted to mount the adaptor internall and have a more durable mains cable running to a female mains power socket on the side although I have no idea how this might affect noise. I'd also be very careful in planning how to get it rock-solid roadworthy: I no longer gig so my DIY efforts tend to be fairly slipshod, construction-wise; if a pedal fails it's no biggie. One advantage of having separate pedals is if you have a problem, it's relatively painless to identify the offending pedal and remove it. Trouble-shooting a 5-pedal behemoth mid-gig with an audio probe is probably not an option.

[diydave]

I've made one with 7 fx in it some years ago:
- tillman pre-amp
- sho
- fuzz face
- tubescraemer + a custom effect (I can switch between the two)
- Rebote Delay
- Easy Vibe

Every fx has it's own in- and output.
No buffer, no special considerations about power; just an external boss adapter into the dc-jack and an elco 100 µF. Just didn't care about it at the time.
Other than the SHO that sometimes play's up (but that is due to the fact that the transistorsocket is lame), no problems (no buzz or other unwanted noise).
If I would do it again (and I will), I would consider the following:
- internal psu. The adapter is sometimes troublesome in live stage situations
- a cleaner way of wiring. It's a real spaghetti now, but no problems with it.
- a nicer finish.




I'm glad I put the pre-amp in; nice drive to fx and the amp, no loss off tone. Maybe better than a buffer? Or be able to switch between buffer at the input or a pre-amp.
To get rid of the ticking on the easy-vibe, I've put in a RC-filter (100ohm resistor - 100µF elco).

[Styles]

Definitely want to go with an internal PSU with a hardwired AC cord- one less thing to lose or break on the road. Any thoughts on daisy chaining the 9v vs running leads from a common point?

[Processaurus]

http://www.diystompboxes.com/smfforum/index.php?topic=46469.0

[amptramp]

One nice thing about a multi-effects unit is that you have control of the input and output impedances for each effect and you don't have to make the effects "general purpose" as you might otherwise.  I would use a buffer for input and output and put all controls between them for any separately-packaged effect, but if you have something with a volume control at an output or an output tone stack, you know the impedance it is going to feed, you might not need to buffer it.

You also have control over the DC interface and some effects will not need to use AC-coupled inputs if the output feeding it is also AC-coupled.  This will save a lot of grief by eliminating electrolytic coupling caps at a device output if it feeds a device with an AC-coupled input.  You could reference an input to Vcc/2 to avoid switch pops.

If you know you are always going to use certain effects in a certain sequence, this allows a bit of design simplification.

[Styles]

thanks for the pointers, much appreciated.  got most of the boards built now, and ended up going with a catlinbread fn5 for the overdrive.  went with the 9v Cincon PCU from mouser, and am just waiting on a few parts from small bear that i didn't have on hand.  i've been planning this out for a while and feel pretty confident about my layout and wiring scheme, only thing i'm not looking forward to is the possibility of troubleshooting 5 pedals at a time- i've never built any of these before (except the zvex but that doesn't count) so keeping my fingers crossed.  the torchy phase 45/vibe looks like a nightmare to go through if its not working right.

[SteveFromBerlin]

Don't forget to post some jummy pics! 

[Perrow]

I haven't built any multi effect yet, but I'd think you'd save some trouble building and verifying the bypasses first, then adding one circuit at a time.

[diydave]

I haven't built any multi effect yet, but I'd think you'd save some trouble building and verifying the bypasses first, then adding one circuit at a time.

Yep.
I first build the bypass circuitry with the leds and checked if it all worked.
Then the fx, making sure they all work as they should before I've put them in the box.
Then implement them one by one.

[Styles]

I haven't built any multi effect yet, but I'd think you'd save some trouble building and verifying the bypasses first, then adding one circuit at a time.

good call, this would avoid massive troubleshooting headaches.  had a dream last night that i should put a kill switch w/ a tuner out on this thing...or maybe just stick my TU2 in front and keep it simple

[petemoore]

  Patch cable/jack/plugs:
 Advantages = reordering effects is 'easy, each box has it's set of particulars {shielding, power filtering, power location, signal routing} all figured out [hopefully] for low noise.
 Disadvantages: Cables, Jacks and Plugs are expensive and introduce thier own set of troubles, the other obvious reasons sometimes make want for multi effects unit.
 Multi Effect Advantages are obvious to anyone using single effect patches + power supply etc.
  Disadvantage is it's more difficult to change anything. Messing with it...makes the entire chain messed with [downtime]
 ...throwing it all in one box...what is 'all' and how might that matter can't totally be known until a physical model of the electronic circuit is made and it's operation scrutinized. Avoiding long signal lines and parallel routing near power supply where noise could be picked up is always a good idea, I've had trouble with a thumping phaser among other things. Finding effects that 'get along with each other' [from PS to boosted signal levels to input impedances to voicings...a lot to think about], is worth a good bit of pre-study if 'commitment' requires a lot of 'backpedalling' to make an effects swap. I was surprized the amount of time and etc. I spend building multi effects, I use patches still.
 Planning of course helps, using the same bypass configuration in the sequence makes it easier to visually check a working bypass as reference, that said, grounded input true bypass might be worth considering in some cases.