Line Effect and Guitar Effect Box - Block Diagram

So I've been thinking about this for a while, and I'm about to wrap up all of my current projects, so i thought it would be a good time to run this by everyone.

So the idea is this. I want to build a box that will allow me to use line levels or guitar levels with a rack mount effects box. It would be based around small guitar effect that can be found all over the internet. I have no specific effects in mind yet, but they should all be able to run on a standard 9V PSU. In this box there will be 1/4" TS jacks to patch any effect in any order. It will also allow for a guitar to be plugged directly into it or come from a transformer that goes from live level to guitar level and then patched to the effects.

That's a bit much to imagine so i made a block diagram to show what I mean.



Is there something I'm missing here? Could I really build this as shown?

Any and all input welcome.

Matt

I'm in on this as I raised the point previously and got some pointers

http://www.groupdiy.com/index.php?topic=158606&highlight=reamp#158606
http://www.groupdiy.com/index.php?topic=13263&highlight=reamp

Howabout a better way of switching effects using relays?
http://www.geofex.com/Article_Folders/fxswitchr/fxswitchr.htm

Thanks for the links. I'll be reading them closely.

The reason I set this up the way I did, is because I think it provides maximum flexibility. Being able to use it as a reamp, a guitar effects box, a DI and as console inserts means that it will have a ton of different uses. have all of the in and out jacks also allows the use of external stomp boxes within the chain if desired. I've decided that I'll probably want to add a power switch to each module so they can be turned off when not in use.

I look at the whole thing as a combo of reamp, DI, effects box and patchbay.

I think this should be doable. I'm pretty confused about the whole impedance transformer part of the equation. I'd like that part to remain passive if it's possible. Just have an internal power supply to replace the typical 9VDC that is used for the pedals, or in this case modules. My console inserts are unbalanced as it is, so it shouldn't need anything special in terms of de-balancing I don't think. Unless I wan to take the signal from the insert and route it to a new input on the console, I guess that could be a little trickier due to the inputs on the board being balanced.

I dunno. I think I'm rambling now.

Matt

basically things are ok

but
the second transformer
Guitar Level to Line Level
is not going to work without some active bits for the lefvel change

HOWEVER
Guitar Level to Mic Level
as a standard passive DI box is fine

Dave's (NYD) reamp or the Jensen reamp is fine on the way in and any of the usual suspects on the way out

use simple guitar patch leads and don't leave the trafos patch when in normal guitar mode

OH
and your drawing sucks !
:shock:
sorry

It took me a while to work out what you ment ... I know it's simple but some of those lines were close and the screen res is bad

reverse the input and out put jacks so the signal flow is more obvious ... use arrow heads perhaps


shut up Kev

Thanks Kev. Sorry about the drawing. I'll make a new one that makes more sense. I suppose that I don't need to actually show all of those effects.

This is going to be a real learning project for me. I've only done things with manufactured PCBs up until now, and I plan to do all of this either point to point or breadboard. Just as a learning exercise. So, I need to figure some things out on my end to know how to proceed, but you've given be a lot of things to think about.

I assume my inserts are working at line level, so it makes more sense to build a Line amp for the output. it's probably a good idea for me to get that and the reamp done before even touching the effects part of this as I can always test stomp boxes to be sure it works.

Thanks for your input.

Matt

Ok, I've decided to just start with the reamp. Get that running, and then move onto the other pieces.

I'm going to try to use NYDaves reamp circuit. I have a question that may be really basic, but continues to confuse me. I have unbalanced inserts that I will typically use to feed the reamp. NYDaves schem shows a balanced input into the transformer. I have no idea how I should wire this up with an unbalanced input.

Why is the unbalanced/balanced thing so hard for me to grasp?

I've decided to not draw up a new diagram due to the fact that these are really going to be 3 different things living in one box and it's hard to show how they all work together without the diagram becoming really cluttered.

Matt

interesting. I've been for the past 4 months been building a similar box.
It will contain 9 guitar pedals that I bought the circuit boards from buildyourownclone.com. All patchable via the front panel, to include a balanced in/out to go to my sound interface.
The balanced in/outs I am building using circuits based upon the chips/datasheets from THATcorp's InGenius and TI's DRV134.
The power supply i'm using is from JLM audio.

I'm also intending to build two low/high pass filters for more sound shaping options, haven't decided where I'll pull the info for that yet.
I'll try to get some pics up soon, man.

cheers~
Jay

don't over complicate it
it is very easy
don't even focus on the balanced thing

reamp box is just a level and impedance converter

Line Level at either -10 or +4 - (a simple switch and resistors to create the pad for the +4 )
then into trafo for the convert of level and imp and the gnd lift if needed
and it comes out Guitar level

then through the effects in any of the normal ways

then to the normal DI box and/or Guitar Amp A/B switch stuff

I've updated the diagram in the first post to be easier to follow, I hope.

I think I've also decided to add some more functionality to this since I need part of it anyway. I'll add the JLM Baby Animal and DI for the output. So it'll have a DI and a Mic input.

This is how I imagine my front panel.

http://diy.fischerworks.com/pictures/GFXbox.gif

Almost time to get started.

Matt

looks ok

are you going to make the effects ?
if so you might want to conseder using the input jack as a switch to remove it from the preceeding unit
... like normaling in a patchbay

guitar pedal set-ups is a never ending process of change.
I tend to like keeping things as seperate units and mix and match.

I have a friend that uses two mic-pres at his feet.
sometimes for stereo guitar and sometimes for his voice.
Being at line level this can run good distance - like at shopping centre performances.
(these days it may be done on radio but in the past)

The Baby animal can probably be made with 2 XL3 outputs and you can provide an earth lift on one of them (both of them).
You can then send a signal to both FOH and Monitor Land.

[quote author="Kev"]looks ok

are you going to make the effects ?
if so you might want to conseder using the input jack as a switch to remove it from the preceeding unit
... like normaling in a patchbay

guitar pedal set-ups is a never ending process of change.
I tend to like keeping things as seperate units and mix and match.

I have a friend that uses two mic-pres at his feet.
sometimes for stereo guitar and sometimes for his voice.
Being at line level this can run good distance - like at shopping centre performances.
(these days it may be done on radio but in the past)

The Baby animal can probably be made with 2 XL3 outputs and you can provide an earth lift on one of them (both of them).
You can then send a signal to both FOH and Monitor Land.[/quote]

Thanks for the reply Kev.

I'm not going to design the effect, but I'll be picking from the whole ton of effects schems on the web. I think the only place they will be linked in any form is at the PSU.

The idea for me is to have them be completely independent of each other so I can patch them in any order with TS patch cables OR be able to route the signal out to an external stomp box and back if I needed/wanted something else in the chain.

I'll be able to run a signal out of my consoles direct outs, through the reamp, through the effects, to the guitar amp. Then Mic the amp with the Baby Animal and record it to a new track.

Or I can use it as insert effect for any variety of sources routing it: reamp, through the effects, to the Di and back to the return.

I won't ever use this live. To be honest, I'm a drummer in the band I'm in, so my guitar rig doesn't get out much. It'll live in my home studio.

Matt

yep

it all sounds very sensible