A/B Box

[Jumpin'Jellybean]

I searched around, and locally it seems we have only the EHX Nano Switchblade as the viable budget option. However, it has 1 input, 2 outputs. I need something with 2 inputs. so, Preferably 2 inputs and 2 outputs, and the Y function will be a plus, but it's not really necessary. Recommendations? Thanks! ( I ain't looking for something dirt cheap but lousy quality, prefer economical but decently built.)

P/S: Doesn't matter how big it is, or whether need to run on power supply etc. Just recommend. Thanks!

 

[PatheinRaindropMoe]

check with TY music center to see if they can build a custom one for you.

Actually theres also offering from radial engineering a/b, a/b/y box available from hung brothers at simlim square 3rd floor. It aint cheap though, due to the circuit inside for what it does.

Most ab, aby box will have only 1 input. To have multiple input and output, you will need to have buffer circuit/phase circuit in it to correct any issue from mixing/splitting signal.

 

[Jumpin'Jellybean]

Thanks for the reply. How bout those with two input/ one output? For example two guitar--->amp, or two pedalboards---->amp.

 

[PatheinRaindropMoe]

go for active circuit mixer to combine signal. Combining signal got more things in it then mathematical addition, theres phase and impedance issue which complicate the process.

If using passive mixer to combine signal, it will likely to get a dull and lifeless sounding signal.

Heh, pardon, i have forgotten what i have learn a while back, so cant explain it in a more easier format. But if need info, this below was one of the site which i used to learn the thing from in regards to mixing signal. The schematic at the end, can be re adapted to building an active mixer/ab box etc with phase control as well, but it will take some searching to gather snippet from various site, trial and error on breadboard before boxing it up.

http://www.all-electric.com/schematic/simp_mix.htm

 

[Jumpin'Jellybean]

Not exactly combining signals. I'm trying to do this...

................----- pedalboard -----
Guitar-----|................................|---------Amp.
................-----Pedalboard -------



Forgive me for my ignorance... I'm pretty new the pedals' technical part.

 

[lazy3yed]

What are the 2 pedalboards' purposes? Your guitar has dual outputs (eg. magnetic and piezo)? Otherwise, how is the guitar connected to the boards?

If you're wanting to switch between the 2 boards, why not use a dual looper, instead? TYMusic can make u a good quality one.

 

[PatheinRaindropMoe]

get a boss line selector, LS 2.

So whats needed, is 1 guitar signal go to 2 loops of effect. Which a A/B box could be enough. If at any time, you need your guitar signal to go into both loop at same time, then go for boss line selector.

Hehe, then back to the first post, then whats with the mentioning of needing 2 input and 2 output?

 

[Jumpin'Jellybean]

Versatility? It's more of a want than a need... But it could function as either 2in1out, or 1in2out.
The problem here is for both efx to go back into same amp. which means i need a 2in1out a/b box, which i've never seen. As mentioned, i could use the nano switchblade to go into 2 different pedalboards, and that's as good as settled... But i need a box with at least 2 inputs. Any particular brands to recommend?

 

[PatheinRaindropMoe]

heh, lets look at things one by one, starting with

In order to have a device with at least 2 input and 1 output, from manufacturer design, it involved mixing signal. If not, theres no point in having a product with 2 in(or more) and 1 out.

With the first thing you mentioned, for versatility sake, if needing either 2 in and 1 out or vice versa, theres passive mixer device which can mix 4 in and 1 out. The good thing is that such device, when the volume knobs on it are all turn up to maximum, it will reverse the input and output, to 1 in and 4 out. An example of such mixer is from rolls(http://www.rolls.com/), which can be gotten from sim lim square, hung bros.

Hehe, world aint perfect unfortunately, since its a passive mixer and not meant for instrument signal like our geetar, it will have issue of phase and impedance mismatch which make geetar sound dull and lifeless(when combining multiple instrument). I have tried this myself, the sound is just dead.

As you mentioned earlier, you dont wanna combine signal, but wanna 2 different groups of effect to go into same amp. So for that, do you want to have 2 different group of effect output into the amp at the same time or at any point, only 1 group of effect output going into the amp?

One last thing, are you familiar with effect looper send/return?

heh, just wanna clarify before going further, got a feeling that thats some missing link on the understanding of guitar signal input path to pedalboard 1 and 2, pedalboard output path(Loop send/return) to amp. Oh, not sure if check out the spec for boss ls 2, if have can use that as example of what it couldnt achieve for what you wanna do. It will be easier.

 

[Jumpin'Jellybean]

I'm not familiar with the effect looper.
Hmm, i'm not thinking so much about mixing signals. I would prefer something like a reverse a/b box, if there's such a thing. Meaning it's like two train tracks going into a particular train station. But i only need one train (signal) to go in at once, so there's something liken a switchable railroad in the middle
Like this...
effect board 1\
.....................-------Amp
effect board 2/
Instead of selecting which output to use, as is the regular a/b box, i want a box in which i can select which input to use. I hope you understand me, i'm not very sure about all the technical terms and this is the best i can do...
The BOSS LS-2 seems to be like a 1 input many outputs, like a regular a/b box (comparing it to a nano switchblade).
http://www.youtube.com/watch?v=F7TC0k6h8nw This was the demo video i watched.


I want two different boards connected to the amp, but i only need one board to be active at once. So let's say if i'm using board 1, instead of turning off 4 pedals and turning on another 3, which is very time consuming, i realized it's easier to use 2 a/b boxes, kinda like a train (signal) which uses two different routes (either effect board 1 or 2) to get to the same destination (amp). And more effects in the chain also means the sound quality gets more dull, no? (That's just a plus point, if it's true).

 

[lazy3yed]

A dual looper is what u need, since u only need 1 board active at any 1 time and no mixing is required. With a A/B box, u'll need 2 and some tap dancing to switch between the 2 boards. Can check out loop-master.

 

[PatheinRaindropMoe]

ok, i know where is the problem liao.

What you wanna, can be done be with boss ls 2 and infact offer more than what you need.

It confused me earlier due to the way you see input/output of the connection you wanna and what is usually known as effect send/return loop.

For the boss ls 2, forget about what you saw or understand from the video. The very basic of it, is

1) Only 1 input, which is where you connect the output from the geetar to

2) Only 1 output, which is going to the amplifier.

3) Loop A (which is what you named Effect board 1)

4) Loop B (Effect board 2)

 

[PatheinRaindropMoe]

And more effects in the chain also means the sound quality gets more dull, no?

Nope. In general, more is not equal to dull. There are reasons what it can be or might not be. Imho, you will be more confused than why it can be, why it might not be, without looking at true bypass, buffer circuit or instrument cable capacitance issue etc.

 

[Jumpin'Jellybean]

A dual looper is what u need, since u only need 1 board active at any 1 time and no mixing is required. With a A/B box, u'll need 2 and some tap dancing to switch between the 2 boards. Can check out loop-master.

Sorry, but how does a looper work?

 

[Jumpin'Jellybean]

ok, i know where is the problem liao.

What you wanna, can be done be with boss ls 2 and infact offer more than what you need.

It confused me earlier due to the way you see input/output of the connection you wanna and what is usually known as effect send/return loop.

For the boss ls 2, forget about what you saw or understand from the video. The very basic of it, is

1) Only 1 input, which is where you connect the output from the geetar to

2) Only 1 output, which is going to the amplifier.

3) Loop A (which is what you named Effect board 1)

4) Loop B (Effect board 2)

How do i fit the two different loops into the signal then? If guitar to LS to amp, where will the pedals fit in?

 

[lazy3yed]

Sorry, but how does a looper work?

A looper, as the name imples, allows you to place effects in loops (or groups) which you can switch in and out off. For example, some looper lets you switch between group A and group B (like this one), some lets you switch loops on/off or chain them together (like this one). These are mostly single purpose loopers, i.e. they only provide one configuration.

In your case, the looper will go between your guitar and the effects boards. Guitar output into looper's input jack. Board 1's input will connect to the looper A's send and output to A's return, board 2's input will go into B's send and output into B's return. Looper's output into amp. Engaging the switch will mechanically switch between loop A and loop B. Some will allow you to totally bypass both loops with a separate switch.

Those like the Boss Line Selector, as suggested by Pathein, allows different combinations (and sometimes more functionality) and are more flexible. The LS should also be placed between your guitar and effects.

 

[Jumpin'Jellybean]

I see, thanks Pathein and Lazy3yed!

But for efx into amp (assuming amp has single input) i will need another box?

 

[PatheinRaindropMoe]

you dont need another box for time being, you just need to really understand what bro lazy3eyed has mentioned on the effect looper part and read the manual of the ls 2(should be able to download from roland site)

Imho, you are confusing things up with loop input(from where), loop output(to where).

In one of the thing you mentioned yourself earlier, this below, is exactly the flow of an effect looper.

............... ----- pedalboard -----
Guitar-----|................................|---------Amp.
............... -----Pedalboard -------

Together with what i mentioned regarding the LS 2

1) Only 1 input, which is where you connect the output from the geetar to.

2) Only 1 output, which is going to the amplifier.

3) Loop A (which is what you named Effect board 1). Loop has a set of input and output, but all along to avoid confusion(which unfortunately might have, in context of the thread), it being known as effect send and effect return

4) Loop B (Effect board 2).

 

[Jumpin'Jellybean]

Yep, i downloaded the manual and i went google to check how to set it up. Now i understand how the ls-2 works, thanks!

 

[theblueark]

I used to build these:

Kinda what you looking for?