Bypass Loops Explained

[warwick.hoy]

I briefly searched and came to the conclusion that most people ('cept for me) already know what a loop is and how it works. I'm referring to those little metal boxes I see on a lot of boards here.

I was hoping for an explanation concerning loops. I understand some (not all) of their purpose, but I'm looking for more of the theory behind them. I find it all a bit confusing but I fear I may be missing out on something that could be useful to me.

~What are the different types of loops? (Buffered? Bypass?)
~Are they like an FX loop on an amp or preamp?
~How does the signal path travel?
~Is there an easy diagram or good resource on the interwebs? ~With a loop can you run some effects independently of others?
~Say you want less tone suck, but want the interplay between another pedal not in the loop; what then?
~Do you leave the pedal on and then click on the loop to get the sound?
~Can I build my own?
~Can someone clear it all up for me?

AGGHH!!!! Can someone clear it all up for me?

[katri]

I'll answer what I can from what I know.

Loops are mostly used to isolate pedals with bad bypass that tends to suck bass from a signal.
So the signal when bypassed would be bass>loop box>amp
When active bass>loop box out>effect pedal>loop box in>amp
Alot of them let you combine loops so even if they are in different loops they can be combined

hope this helps

[warwick.hoy]

katri; thanks for your reply. It helps a bit.

Originally Posted by katri

I'll answer what I can from what I know.

[b]Loops are mostly used to isolate pedals with bad bypass that tends to suck bass from a signal.

That's what I gathered but I was wondering if there were other reasons...some pedals not playing nicely with others....etc.

Originally Posted by katri

So the signal when bypassed would be bass>loop box>amp
When active bass>loop box out>effect pedal>loop box in>amp
Alot of them let you combine loops so even if they are in different loops they can be combined

hope this helps

I've seen some loops that have 5 or six switches...for this purpose perhaps?

[katri]

yeah, each Effect is in it's own loop and any number can be selected at once. Some also have a blend which adds clean signal to pedals that suck tone while in use.

[warwick.hoy]

Originally Posted by katri

yeah, each Effect is in it's own loop and any number can be selected at once. Some also have a blend which adds clean signal to pedals that suck tone while in use.

[katri]

Originally Posted by warwick.hoy

That's what I gathered but I was wondering if there were other reasons...some pedals not playing nicely with others....etc.

also some people prefer having switches for all their effects in one place, some pedals have a pop when the switch on and some turn on or off slowly

there are loads of reasons

[Doolz]

they are also useful for turning on multiple pedals with one click.
for example say in the chorus of a song you wanted to use distortion, phaser and tremolo, but didnt have time to click all three on at once, with those pedals in their own loop, you can switch them in with one stomp.

[varunkapahi]

i dont at all understand what is the loop's send and return. can some one explain that?
i go dizzy everytime someone here writes about working with a boss ls-2 :-/

[kevteop]

Originally Posted by varunkapahi

i dont at all understand what is the loop's send and return. can some one explain that?
i go dizzy everytime someone here writes about working with a boss ls-2 :-/

A simple bypass loop isn't as complex as the LS-2. With a simple bypass loop you get:

In -> (Send -> [some effects in the loop] -> Return) -> Out

When you switch the loop off, everything in the loop is cut from the signal path completely, so it just goes straight from In to Out. Hence the term "bypass".

An LS-2 can operate the same way, and it lets you set up two loops to choose from, but it has other modes too. Go to the Boss site and download the manual if you want to read more - there's a lot to explain!

[bongomania]

"Send" is where the loop begins, it is an output jack. "Return" is where the loop ends, it is an input jack.

send --> fx --> return

[bongomania]

"Buffered" means a small amplifier-type circuit is used to electronically route the signal to either the bypass or the effect circuit.

Pros: usually cheaper to make, often able to reduce the signal loss that happens over a long cable run, usually has no "pop" when switching, easier to implement with relays (which means much greater versatility when designing complex switching systems).

Cons: very often designed/built quite poorly, leading to "tone suck" when you bypass the effect. Quality-oriented (instead of low-cost oriented) design/build avoids this.

"True bypass" has no one correct definition physically, but the concept is that there is absolutely no tone loss when bypassed because your input signal gets directly connected to the output by a physical wire. Usually this is done with a 3PDT switch, but there are other methods. Not all manufacturers tell the truth when they advertise "true bypass" because they conveniently use their own shaky interpretation of it. It's easy to tell if a pedal is true bypass if it has a 3PDT switch, but again not having one is not proof that the pedal isn't true bypass.

Pros: no tone suck when bypassed.

Cons: sometimes there's a loud "pop" noise through your speakers when switching (it will happen at random in different environments); the nature of the switch means your instrument signal is loaded very differently in bypass versus engaged; no buffering to prevent signal loss over long cable runs; cheaply-made 3PDT switches break easily.

[warwick.hoy]

Good Morning and Thanks Cyrus,

What would be an example of a quality buffered loop ie who makes one?

[fuNKmaster83]

for example... big shot mix pedal from radial has buffered loop and it has a mix of that loop and a phase reverse... and that is more than you need... its all quality made... you can use buffered loops as booster!!!

[warwick.hoy]

Originally Posted by fuNKmaster83

for example... big shot mix pedal from radial has buffered loop and it has a mix of that loop and a phase reverse... and that is more than you need... its all quality made... you can use buffered loops as booster!!!

looks nice...but pricey.