Blender again - Question about two options

[jkokura]

So a while back, I tired building a Mini-Blender into a Volume Shell I had. Fail. First time I've not been able to get something to work at all. I think there's a problem with the whole idea, cause I can't find any evidence of it being a verified circuit anyway.

On to new ideas though, and I've found two:

Buff n' Blend - http://www.aronnelson.com/gallery/main.php/v/BarcodeVeroLayouts/album120/buffnblendPCB.gif.html

B.Blender - http://www.aronnelson.com/gallery/main.php/v/BBlenderDIY_001.gif.html

Which should I try? I've heard the Buff N' Blend can cause issues if a gain or boost circuit is in the loop, but the B. Blender has a higher parts count and I'd like it to be a bit smaller if I can. Also, I'm gonna be perfing this so the Buff N' Blend is my first choice, I just want some feedback as to whether I'll see issues should I go with it.

Jacob

[jkokura]

Bump?

[will queue for free stuff]

Jacob,
Do you still have your Mini-Blender?
I checked the layouts gallery,
what I found was a Jack Orman design;  his simple JFET buffer.
All values where consistant with his design. Check it out
http://www.muzique.com/schem/eagle.htm
The buff 'n blend is essentially the same circuit with R values reduced to make it less bright.
Jack Orman talks a little about these types of changes in his article.
Switch out your JFET if you still have your circuit, I built it this morning and it worked fine.
J201 will give you a little more gain than the 2N5457.
Good Luck
Craig.

[jkokura]

I couldn't get the mini blender to work. I think I'm going to switch to the Fet buffer. Not sure what I'll use - any recommendations on what transistor to use?

Jacob

[Derringer]

I couldn't get the mini blender to work. I think I'm going to switch to the Fet buffer. Not sure what I'll use - any recommendations on what transistor to use?

Jacob

I've done it with J201's and 2n5457's ... 2n5457 is a bit better suited to be a buffer, but both have worked for me without issue

The problem that will arise using either the buff'n'blend or the bblender is that some effects will output a signal that is 180 degrees out of phase with the input signal, which means you'll get a canceled sound on the output ... probably be nasally sounding.

I'd recommend that you build ROG's Splitter-Blend which is designed with a phase switch to remedy the issue.
http://www.runoffgroove.com/splitter-blend.html

I know you said you'd be working with perf, and there is a perf layout in the linked Splitter-Blend article, but i see there is also a PCB transfer in the layouts gallery here
http://www.aronnelson.com/gallery/main.php/v/ANY-machines/album47/Splitterblendpcb.png.html
http://www.aronnelson.com/gallery/main.php/v/ANY-machines/album47/Splitterblendpartslayout.jpg.html

[jkokura]

Thanks for your suggestions. I don't have any spares of those trannies I don't think. I have some extra 2N5952's, 2N5088's and 5089's, and I think from 3904, but I don't think any are acceptable but the 5952's.

The problem with the splitter blend is that A) it's too big for the enclosure I'm working with, and B) it's got two sends, which i'm not sure how to deal with. From what I see of the Splitter blend it's meant to blend whatever the two loops have in them. That's not what I'm wanting. What I'm wanting is a way to blend one pedal with my DRY signal. So when the pedal is fully on, all I'm getting is the wet signal of the loop, and when it's fully off all I'm getting is my dry signal. I don't want extra knobs, just the Blend knob. I can deal with a trim pot to control the orignal volume, but there is no space in my volume enclosure for a second exterior knob, let alone multiple knobs.

I'm working on Perf because I don't etch.

Jacob

[Derringer]

to use the splitter blend to blend an effect with your clean, you would just jumper the one loop using a patch cable (so send1 goes direct to return1) and then run the effect through the other loop (send2 to effect input, effect output to return2)

[jkokura]

I really, really, really appreciate the suggestions. I love that about this community. But again, the splitter blender is too big, and too many parts. I think I'm going with the FET blender. It's simple, small, and I know it works.

What effects will be affected by this phase issue mentioned? I probably won't be using any of those I don't think. If I do I'll just find other options. I have way too many pedals, and I'm not worried about finding other options.

Jacob

[Derringer]

right on man

How small of an enclosure are you talking about?

it's impossible to say exactly which effects output a signal that is inverted from the input ... but if those are the two options, I'd assume that roughly half of all effects invert the output

[jkokura]

I have some pictures around here somewhere... Probably in another thread.

It's essentially like the Line 6 enclosures for their expression pedals. It's made by a company called Bespeco. The trouble is that there's limited space to mount the circuit, because the inside isn't flat, and the bottom plate is aluminum and grounded. So basically, I have about 1.5 square inches, and I think I could squeeze the BBlender in, but it might not fit.

I emailed Dan at This1smyne, he recommended the FET blender also. He has a version of it available through his website. I didn't ask him about the phase issue though...

Jacob