True Bypass with Latching Relays

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did he? (EDIT: the OP 'decided') ah well, we weren't really helping after your (EDIT:pRR) reply anyway, just arguing :)  :-[

cheers cc for clearing that up, i was feeling a little unwelcomed, thought i'd really hit a nerve, that wasnt my intention.
anyway, not sure if he sorted it (the OP)but he did mention it was for use on a single pedal, and i have to agree i would use the AMZ in single boss pedals without doubt. thats a good solution and alternative to an ugly carling sticking out of a DD6. and i dont doubt its MANY uses of course.
if he can somehow get the AMZ board from the US.. or reproduce the design for his single pedal where he is (third world?) then awesome.


apologies for off topic.
cc, please dont be offended, i am only talking.. Re: your pedals, i was referring to all the ground loops and trouble i have had eliminating DC noise introduced through PSU's and radio interference when using complex (or even simple) loops.
there were several sources of noise which override any fear of 'tonesucking' or true bypass concerns.

the first is with ground loops in a simple chain, i.e. stereo pedal has two 'outs', into two 'ins' of second stereo pedal being the simplest. in my experience even this can introduce radio interference. the there are extensions of this like signal splitters or a-b boxes with shared grounds, the loop becomes huge when you use two amps for your stereo signal and it is completed via the earth connection of the two amps!
very noisy. much worse than the damage say a 'Whammy IV' could introduce to your tone. and they are notorious.

secondly, you have noise introduced through your DC ground, which is often also shared. there are two more possibilities for noise here. the first being poor regulation of the DC initially, introducing hum etc. which is amplified particularly in high gain pedals. and the second being noise introduced to your DC supply by a pedal (eg. behringer or Line 6 modular range, i forget their names) although this is kept isolated within the pedal itself if they have a seperate psu, the DC noise on the common goes straight to any other pedal sharing the power and comes out the speakers.

this kind of noise can rarely be eliminated by seperatley regulated supplies as they still share a ground, although i think what you have is a voodoo2+ on the left?
i think this one has a separate winding for each isolated out??? this will stop that particular kind of noise coming back in.

that brings us to the ac adapters and transformers. in my experience you get more noise introduced through ac adapters which use transformers close by, than through any 'non' true bypassed pedals. I had to pay particular attention to how close they were, what's between them and even what angle they were at. plonking a pedal on top of your ac is probably not the best way to go if your worried about noise. especially ones with plastic shells like mine were back then.

personally i think true bypass has its place. its great for taking your wah out from before your fuzz face, as the proper FF relies on the changes of your guitar pickups impedance for its sound. but after the last of your first section (gain,dist,OD etc.) i see little benefit to true bypass and i certainly make sure there is a buffer before the end of the pedal board because you then gotta trail that signal all the way back to your amp!

but theres more to it than that of course, not saying i know it all. just saying :)
 
kepeb said:
secondly, you have noise introduced through your DC ground, which is often also shared. there are two more possibilities for noise here. the first being poor regulation of the DC initially, introducing hum etc. which is amplified particularly in high gain pedals. and the second being noise introduced to your DC supply by a pedal (eg. behringer or Line 6 modular range, i forget their names) although this is kept isolated within the pedal itself if they have a seperate psu, the DC noise on the common goes straight to any other pedal sharing the power and comes out the speakers.

this kind of noise can rarely be eliminated by seperatley regulated supplies as they still share a ground, although i think what you have is a voodoo2+ on the left?
i think this one has a separate winding for each isolated out??? this will stop that particular kind of noise coming back in.

that brings us to the ac adapters and transformers. in my experience you get more noise introduced through ac adapters which use transformers close by, than through any 'non' true bypassed pedals. I had to pay particular attention to how close they were, what's between them and even what angle they were at. plonking a pedal on top of your ac is probably not the best way to go if your worried about noise. especially ones with plastic shells like mine were back then.

Yup - on the left is a Voodoolabs Pedal Power (separate windings from the transformer [which is a Toroidal - so a little better at not inducing EM noise onto other things]) each regulated down to around 9v.  The right one is a BBE Supracharger - which is exactly the same thing as the Voodoolabs Pedal power.  Literally, it is the same PCB board with some different switchable options on the voltage output.

With an unbalanced setup you are always connecting grounds to one another.  You sorta have to.  The shield of the cable connects the chassis of each pedal to one another.

The Line6 modelers can use DC but they ship with AC adapter that outputs 9V AC (has an internal rectifier which is why DC also works) I guess it's totally possible for an AC wire to induce more noise... I don't know.

I haven't really compared true-bypass pedals noise vs. none true-bypass pedals.

I guess if you have a truebypass effect that is simply passing through with a bunch of unbalanced wire you could pickup more noise problems.  I use decent cables and ends (Mogami), not that I'm a cable snob - it's just easy to work with and was reasonable cost actually.  When a pedal is not a true bypass you likely benefit from RF filtering (if it exists) in the buffer circuit, thereby reducing noise?

I don't have any noise problems with my setup.  This is good especially considering that I am often running 2 overdrive pedals (one with a boost) into a distortion pedal in series.  Lots of stacked gain with the potential for lots of noise.

CC
 
conleycd said:
I haven't really compared true-bypass pedals noise vs. none true-bypass pedals.
no me either, but the noise introduced through other paths is more important to worry about than getting TB tone imo.
conleycd said:
I guess it's totally possible for an AC wire to induce more noise.
I hadn't mentioned, or thought about that but yes... i guess it probably would to an an extent.

i've never looked inside a one of those pedals, i had a 'verbzilla' before, i thought the sound was great, but you try and get it to play nice when sharing a DC psu, i couldnt.

and your right, all the sleeves are common, and when experimenting with alternate loops (and looped musical sections) via two amps with switching, i found the only way to get rid of all the noise was to use a 1:1 ground isolation in one side of the stereo before the amp. although just cutting the ground in one of the 2nd sides patch leads gave surprising results too, better than my first (ART accessories :() a-b box did.

conleycd said:
exactly the same thing as the Voodoolabs Pedal power.  Literally, it is the same PCB board with some different switchable options on the voltage output.

now that is Very interesting, i thought there would be more of a difference than £30 and a paint job. i got some cheap psus with diy regulators. but i know which one to get if i ever fork out now. ta.
 
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