DIY blend question

flakeh · #1 01-01-2008, 06:12 PM

First off, Yes, I have searched, but have not found the answer I need.

Ok, heres what I need/want

I wanted to bi-amp (ala tim C) but that is just to expensive and unpractical for me, So I want to have a 2 input, 1 output blender. on my board I have an EQ with 2 outs, this is the first thing in my chain as I use it for a boost. output 1 of this goes into my effects, while output 2 is unused. basically, I want a box with 2 inputs, a single output, with some kind of blend control to blend signal 1 with signal 2, and then go to my amp.

So, Can anyone send me or post a schematic for a simple, easy to use blend pedal?

BTW, this will be my second DIY electronic thing, So the simpler the better.

bongomania · #2 01-01-2008, 06:19 PM

http://www.seanm.ca/stomp/minblend.html
http://www.seanm.ca/stomp/bblender.html

flakeh · #3 01-01-2008, 06:21 PM

Quote:

Originally Posted by bongomania

http://www.seanm.ca/stomp/minblend.html
http://www.seanm.ca/stomp/bblender.html

I've read these, but they won't really help my cause. I need 2 signals blended into one, but with only 2 inputs and 1 output.

Thanks anyway

Tomass · #4 01-01-2008, 06:27 PM

Do you want to be able to control the signal from both inputs? Or just have it so that the split signal is just gelled together, with no measure of control. Basically if thats what you want to do, just build a reverse Y box.

EDIT: Yer the 2 links that Bongomania provided should do the trick.

bongomania · #5 01-01-2008, 06:27 PM

Errr... they will do that. Just think of "return" as "input #2".

flakeh · #6 01-01-2008, 06:32 PM

Quote:

Originally Posted by bongomania

Errr... they will do that. Just think of "return" as "input #2".

...those blenders all have an input, an output, a send and a return, I need 2 inputs blended into 1 output.

Tomass - , basically a reverse Y box with a control on how much signal A is blended with signal B

Pretty much , I want http://smallbox.zeonhost.com/projects/abbox/ that, but with a blend control instead of a stompswitch

oh piss, It seems I have confused the hell out of myself. the B blender is practically it. Is there any simpler schematics out there? I am horribly lost in all the talk of opamps and junk.

Tomass · #7 01-01-2008, 07:13 PM

A passive one would be the eaiset option then, with having jacks, wire, and two volume pots.

unclejam · #8 01-01-2008, 07:22 PM

Just stick a Blend Pot in place of that Switch and take out the Leds

flakeh · #9 01-01-2008, 07:28 PM

Looks like that is what I will be doing.

So, All I need is an enclosure, 3 jacks, and a blend pot?

Whats a good pot to get? 500k?

unclejam · #10 01-01-2008, 07:33 PM

Quote:

Originally Posted by flakeh

Looks like that is what I will be doing.

So, All I need is an enclosure, 3 jacks, and a blend pot?

Whats a good pot to get? 50k?

yes and if you are concerned about Volume loss then slap a clean boost before your amp

flakeh · #11 01-01-2008, 07:35 PM

Quote:

Originally Posted by unclejam

yes and if you are concerned about Volume loss then slap a clean boost before your amp

Or, just turn up the gain..

Alright, I'm gunna order the parts needed from small bear tommorrow, in the mean time...how the hell do I wire this thing...

unclejam · #12 01-01-2008, 07:43 PM

Wire The Sleeves Together
Take the Tips(coming in) and Put those on the Outer Lugs of the Blend Pot
The Center Lug Goes to the Output Tip

or just fallow the directions in the packaging

speak_onion · #13 01-01-2008, 07:46 PM

I don't like this passive idea. Depending on how your EQ is wired, you might have feedback problems and/or impedance problems.

I would do the B. Blender (I actually have the parts for 3 B. Blenders in transit to me) but omit the top left opamp and its 470K resistor and the send jack. Then think of the input as Input 1, and the Return as Input 2. Voila.

I know I'm sort of repeating what's been said, but I just want to throw my 2 cents in since I just had this same problem.

flakeh · #14 01-01-2008, 07:48 PM

Quote:

Originally Posted by speak_onion

I don't like this passive idea. Depending on how your EQ is wired, you might have feedback problems and/or impedance problems.

I would do the B. Blender (I actually have the parts for 3 B. Blenders in transit to me) but omit the top left opamp and its 470K resistor and the send jack. Then think of the input as Input 1, and the Return as Input 2. Voila.

I know I'm sort of repeating what's been said, but I just want to throw my 2 cents in since I just had this same problem.

I would do that. But I am a major noob in the DIY electronics area. I've made a aby box, and a feedback loop box. Thats it. Opamps and that stuff confused me like made. If a simpler schemetic is available (not likely) then I could possibly do it.

dewbass4 · #15 01-01-2008, 08:11 PM

How about just buying a small simple mixer like this one.
Cheap and easy fix to your problem with inputs to spare. If the TRS output is and issue a simple stereo to mono adapter should do the trick.

bongomania · #16 01-01-2008, 08:14 PM

Passive blending sucks the big one and is not a good idea. I strongly recommend you build the active blender (with opamps and all that) or buy a small mixer.

Tomass · #17 01-01-2008, 11:28 PM

Quote:

Originally Posted by bongomania

Passive blending sucks the big one and is not a good idea. I strongly recommend you build the active blender (with opamps and all that) or buy a small mixer.

Fair enough, you learn something new everyday.

flakeh · #18 01-02-2008, 10:45 AM

Quote:

Originally Posted by bongomania

Passive blending sucks the big one and is not a good idea. I strongly recommend you build the active blender (with opamps and all that) or buy a small mixer.

That is a great explanation Bongo.

I might build the minimal version of the bblender, It needs one opamp or a FET transistor instead of opamp, And it seems not too too hard. If it fails then I'll get a cheapy mixer.

bongomania · #19 01-02-2008, 11:26 AM

Well, I don't know if it was any explanation

but it's my opinion anyway. An explanation would be that the two signals fed into a passive blender would be loaded down (their output impedance would no longer be optimal for the input impedance of the next device in line), probably resulting in a loss of highs and possibly also resulting in weaker signal levels or phase interference (from cancellation to doubling).

Sean S · #20 01-02-2008, 01:41 PM

Quote:

Originally Posted by bongomania

Well, I don't know if it was any explanation

but it's my opinion anyway. An explanation would be that the two signals fed into a passive blender would be loaded down (their output impedance would no longer be optimal for the input impedance of the next device in line), probably resulting in a loss of highs and possibly also resulting in weaker signal levels or phase interference (from cancellation to doubling).

HERE'S an explanation

There's also the possibility of electronic feedback with passive blenders, no?