a general layout for 'blend' ?

Frequent asked about building blocks: gain stages, buffers, clipping configurations, ...
nezek
Posts: 17
Joined: 28 Jul 2008, 00:18

Post by nezek »

Hi, tried to search but couldn't find something that helped me..
I want to add a blend control (dry/wet) to a wah..
Do I need an active mixer or just a pot..?
thanks

User avatar
moltenmetalburn
Resistor Ronker
Posts: 300
Joined: 03 Nov 2008, 15:01
Location: Dirty Jersey
Been thanked: 3 times

Post by moltenmetalburn »

I have never used a passive blender that sounded any good.

you can try this one, Joel Purkiss' Buff n' Blend Ive had some success with it in the past.

http://www.geocities.com/jrtookmyfalset ... ffblnd.gif
http://www.geocities.com/jrtookmyfalseteeth/buffpcb.gif
http://www.geocities.com/jrtookmyfalset ... ffwire.gif

OR this if you favor op amps, if you tie Send 2 to Return 2 and omit the jacks youll have a blender that blends with the dry. The Runoffgroove Splitterblend.

http://www.runoffgroove.com/splitter-blend.html

OR the Mooseapotamus Paralooper, originally designed for bass. If you omit the low pass filter on the clean signal you'll have a full range blend.

http://www.moosapotamus.net/THINGS/para ... perSCH.gif
http://www.moosapotamus.net/THINGS/para ... operTT.gif
http://www.moosapotamus.net/THINGS/para ... perLYT.gif

Good luck blending! :ROFL
"The Humans Will Never Destroy Us"

nezek
Posts: 17
Joined: 28 Jul 2008, 00:18

Post by nezek »

wow cool :)
thanks

kurtlives
Solder Soldier
Posts: 175
Joined: 20 Jan 2008, 03:18
Location: Toronto, Canada.
Been thanked: 2 times

Post by kurtlives »

moltenmetalburn wrote:I have never used a passive blender that sounded any good.

you can try this one, Joel Purkiss' Buff n' Blend Ive had some success with it in the past.

http://www.geocities.com/jrtookmyfalset ... ffblnd.gif
http://www.geocities.com/jrtookmyfalseteeth/buffpcb.gif
http://www.geocities.com/jrtookmyfalset ... ffwire.gif

OR this if you favor op amps, if you tie Send 2 to Return 2 and omit the jacks youll have a blender that blends with the dry. The Runoffgroove Splitterblend.

http://www.runoffgroove.com/splitter-blend.html

OR the Mooseapotamus Paralooper, originally designed for bass. If you omit the low pass filter on the clean signal you'll have a full range blend.

http://www.moosapotamus.net/THINGS/para ... perSCH.gif
http://www.moosapotamus.net/THINGS/para ... operTT.gif
http://www.moosapotamus.net/THINGS/para ... perLYT.gif

Good luck blending! :ROFL
How would you alter the Paralooper to be used with guitar?

User avatar
moltenmetalburn
Resistor Ronker
Posts: 300
Joined: 03 Nov 2008, 15:01
Location: Dirty Jersey
Been thanked: 3 times

Post by moltenmetalburn »

OR the Mooseapotamus Paralooper, originally designed for bass. If you omit the low pass filter on the clean signal you'll have a full range blend.
full range= guitar.

if you needed more specific information replace R6 with a jumper and remove C5, and it's now a regular blend pedal. [smilie=a_bigteeth.gif]
"The Humans Will Never Destroy Us"

nezek
Posts: 17
Joined: 28 Jul 2008, 00:18

Post by nezek »

the original plan was for a bass wah so I won't need it :)
but pretty cool ideas & schems there

ifeellikeatourist
Posts: 8
Joined: 31 Jan 2009, 04:02

Post by ifeellikeatourist »

So, how hard is it to put a clean blend knob into a pedal? How does one go about doing this?

earthtonesaudio
Transistor Tuner
Posts: 1256
Joined: 28 Jan 2008, 05:00
Completed builds: Metal Simplex, Fuzz Factory, two Fab Echos-modded, Noisy Cricket, Earth & Space Wah, TS-7-modded, passive xover/splitter box, opamp fuzz
Location: Bloomington, Indiana
Has thanked: 9 times
Been thanked: 68 times

Post by earthtonesaudio »

The answer to the first question depends upon which of the many ways you could answer the second question.

Easy and will work with any pedal:
Splitter at the input
Mixer at the output
-Dual-ganged pot turns effect output down while turning "clean" output up.
-Alternatively, separate volume controls for "effect" and "clean"

I'd use an op-amp for the mixer stage, for sure. This gives you the option of configuring it as a "summing amplifier" or a "difference amplifier" depending on whether the effect inverts the phase.

For the input, my first choice would be the other half of a dual op-amp, or a JFET if using a single op-amp.


...But there are many ways to do this, depending on your preferences.
rocklander wrote:hairsplitting and semantics aren't exactly the same thing though.. we may need two contests for that.

User avatar
moltenmetalburn
Resistor Ronker
Posts: 300
Joined: 03 Nov 2008, 15:01
Location: Dirty Jersey
Been thanked: 3 times

Post by moltenmetalburn »

"The Humans Will Never Destroy Us"

User avatar
moaner70
Posts: 21
Joined: 24 Mar 2009, 19:01
my favorite amplifier: one that works
Completed builds: Wooly Mammoth
Muff Fuzz
B Blender
Tube Screamer
Stereo input dual B Blender with mixer and switchable dual out for single or bi-amp
Bass Balls mod
Catalinbread SFT
Brassmaster
Idiotbox BlowBox
Has thanked: 3 times

Post by moaner70 »

Hi

I'm looking to build the following "B Blender" as designed by Sean M for use on a Bass. Not yet verified but if someone wants to cast an eye over the layout i'd be grateful before I commit to building it. The ground is on strip K and I do plan to connect the ground of all the jack sockets and battery to ground also.

Image

This is from Sean's original schematic at his website

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

Thanks
Mark

User avatar
moaner70
Posts: 21
Joined: 24 Mar 2009, 19:01
my favorite amplifier: one that works
Completed builds: Wooly Mammoth
Muff Fuzz
B Blender
Tube Screamer
Stereo input dual B Blender with mixer and switchable dual out for single or bi-amp
Bass Balls mod
Catalinbread SFT
Brassmaster
Idiotbox BlowBox
Has thanked: 3 times

Post by moaner70 »

I can now verify this works. I've amended the layout slightly and moved R5 to the other side of C8 as below.

Image

User avatar
JiM
Diode Debunker
Posts: 911
Joined: 11 Mar 2008, 23:56
Completed builds: Mods & Reverse Engineering :
Harley Benton GA-5 (input impedance, gain/bright switch, removed tone pot reused for master volume, output attenuator, 3P4T bias selector for stock/marshallish/fenderish/other mods, parallel 6N1P output stage)
Behringer VP1 (univibe cap ratio)
Behringer VD1 (first clipper diodes bypass for bass)
Behringer VB1 (external range pot for each filter, fast/slow switch)
Behringer AB200 (conversion to loop swapper)
Behringer Hellbabe wah (mechanical improvement)
Rocktek Distortion (switch Si/LEDs/none diode clipper)
Marshall Valvestate 8240 (dry and chorus mix)
Danelectro FabTone (removed a clipping diode, moved gyrators)
Joyo AC-Tone (HP sim bypass)
Location: France
Has thanked: 17 times
Been thanked: 28 times

Post by JiM »

Why don't you use some quad opamp, such as a TL074 ? It would be easier and take less space.
BTW, these 741 will be quite noisy ... and they may need some offset compensation.

User avatar
moaner70
Posts: 21
Joined: 24 Mar 2009, 19:01
my favorite amplifier: one that works
Completed builds: Wooly Mammoth
Muff Fuzz
B Blender
Tube Screamer
Stereo input dual B Blender with mixer and switchable dual out for single or bi-amp
Bass Balls mod
Catalinbread SFT
Brassmaster
Idiotbox BlowBox
Has thanked: 3 times

Post by moaner70 »

Thanks for the tip Jim, maybe next time. Would a TL074 be less noisy than a couple of 741? Or is there a better design I could use for blend?

User avatar
lolbou
Old Solderhand
Posts: 2743
Joined: 18 Nov 2008, 22:38
Has thanked: 266 times
Been thanked: 168 times

Post by lolbou »

moaner70 wrote:Would a TL074 be less noisy than a couple of 741?
Sure it will!! But you can improve your existing design with other single opamps (e.g. TL071..) with better noise characteristics...
- Are you a mod or a rocker?
- Uh, no, I'm a mocker.

User avatar
moaner70
Posts: 21
Joined: 24 Mar 2009, 19:01
my favorite amplifier: one that works
Completed builds: Wooly Mammoth
Muff Fuzz
B Blender
Tube Screamer
Stereo input dual B Blender with mixer and switchable dual out for single or bi-amp
Bass Balls mod
Catalinbread SFT
Brassmaster
Idiotbox BlowBox
Has thanked: 3 times

Post by moaner70 »

Lolbou, could I substitute the 741 for a TL071 in the design without any other changes? Just a case of slotting in the new IC's?

Image

User avatar
lolbou
Old Solderhand
Posts: 2743
Joined: 18 Nov 2008, 22:38
Has thanked: 266 times
Been thanked: 168 times

Post by lolbou »

Sure, same pins, no change... Unless you need the dirtyness of the 741 in this circuit, like in the MXR Dist +... :)
- Are you a mod or a rocker?
- Uh, no, I'm a mocker.

User avatar
Gino
Posts: 8
Joined: 12 Jan 2009, 03:20
Location: Royal Oak, MI
Contact:

Post by Gino »

Would this work for a Dry Blend control? Or would it overload the input, output or do something else strange? If so, how could this be fixed to allow for a dry blend on the output? Thanks in advance. :)

Image

Sorry for posting this on every DIY stompbox forum but I want to get as much input as possible.

User avatar
Gino
Posts: 8
Joined: 12 Jan 2009, 03:20
Location: Royal Oak, MI
Contact:

Post by Gino »

Ok, I just found this topic. Sorry. :oops:

plexiplud
Posts: 2
Joined: 03 Jun 2009, 15:11

Post by plexiplud »

If I wanted to drop this circuit into an existing overdrive pedal, such as my MXR Distortion III, where abouts in the circuit would i want to put it? I have a pretty basic understanding on circuitry at the moment but im hoping to try to learn alot more from here... cheers.

User avatar
lolbou
Old Solderhand
Posts: 2743
Joined: 18 Nov 2008, 22:38
Has thanked: 266 times
Been thanked: 168 times

Post by lolbou »

You mean adding a gain stage in it?
- Are you a mod or a rocker?
- Uh, no, I'm a mocker.

Post Reply