SSS blender/blower

[moosie]

Hi folks. Having got lucky once, soldering my Strat to JohnH's HSS spec, I am now climbing further out on the limb.

I asked the other day about a simple blender circuit, and got a good answer. But on reflection, I wanted a couple more things. None of them critical, but I'm enjoying the game. I've linked my component diagram, and would love someone to look it over. First time I've done this, so don't break a rib laughing.

Note: I noticed I removed the image from my site, breaking this post. Here's the image, but it's the final version, which is probably different from the original that used to display here. This is the version currently in my Strat. I love it!


The design goals are stock Strat with the following differences:

1. Blender (instead of 2nd tone pot). N, N+M, M all can blend in B. M+B, B can blend in N. A simpler design would have been M blends nothing, but I rarely play B alone, and unlike many people, I actually like M at times. A little bit of B bite would be nice. Alternatively, M-blend-N didn't seem useful. Positions 2 and 4 allow for all three pickups, and of course positions 1 and 5 both allow for N+B in varying blends, for a Tele-ish feel.

2. Simple treble bleed mod. I have liked similar values as these, in series in the past.

3. Master tone. This is a no-click no-load pot, designed to go out of the circuit on 10. I'm also trying a couple of things, perhaps too much at once... 50s vintage wiring, connecting tone to volume's middle lug; and the Greasebucket circuit. I do use the tone knob, and hate it getting muddy. Maybe vintage and treble bleed is unnecessary? Too bright for a Strat, all around?

2. Volume pot is push/pull. What I'm calling a Blower switch for simplicity. It's more of a Direct switch. When pulled, the volume, tone, and blend pots are out of the circuit, but the pickup selections are left alone. I don't have the need for a "solo button", so no bridge-only, series, etc. The "surprise" not-really-wanted feature here is that by removing all the pot loads, there is no blend. So, if you were blending, pull the switch and you're not.

The blower does two things: pickup hot connects directly to the middle lug of the volume pot, where it heads out of the guitar; and ground is lifted from the volume and tone pots (and these are differentiated from pot shell grounding). Does this look right?

I'm not sure until I wire it up (feel free to chime in here) how the blender will work. Have I chosen the correct lugs? I've gone to lengths to ensure that the bridge always goes to the same lug, thinking this may keep the direction of turn more understandable. But maybe I've gotten this wrong. It was very cool to figure out how to do that bit, though ;D

The Blender is no-load, clickless, and it's my understanding I need this because otherwise when logically "zeroed", there will still be some of the other pickup coming through. Is that right? Again, correct lugs and all? I just can't quite wrap my head around that part.

You'll notice the star ground wiring. Some of that's needed for the blower-ground-lift, but I also prefer to wire that way. If you see problems with it, fire away.

I'm sure this is a pretty simple circuit for many experienced modders. I'm just getting started, and this took quite a while to figure out. Any feedback before I learn by the trial of hot iron is much appreciated.

And of course if you want to build it first, let me know how it goes But hurry, I'm getting the parts as we speak.

Cheers.
-joe

[newey]

Hey, moosie.

I took the liberty of displaying your diagram so we can discuss it without everyone having to click through to see it.

Your graphics are great, we've seen a lot worse first diagrams, so no one will be laughing. At least, not too hard . . .

I'm not too sure on the workings of the blender here. I'm not prepared to say that it won't work- but I'm also not able to say that it will. either. Let's let others have a peek at it.

I don't think you need to bother to lift the ground on the "blower" switch, probably won't make a difference either way.

On the "greasebucket" tone thing, that's a whole 'nother area for discussion, but if that's what you want, it looks OK on your diagram.

[JohnH]

Hi moosie, lots to look at here. I'll post this before looking at the blender part, since that needs more consideration.

First, very mice graphics. What do you draw with?

Tone pot:
I dont think you can mix 'greasbucket' with 'no-load'. The greasebucket circuit does whatever it does using all lugs of a normal pot. If you have a break in the track it can't function as intended. I had these on my Strat, and actually didn't find anything interesting about them, other than that you dont get the mid peak as you approach 0, which I quite like to have. I put in no load to take some load off my humbucker. So Id suggest doing one or the other. Have you had either of them on other guitars?

Treble bleed v 50's wiring
Two other things not to mix (unless you have already tried it and like the result). Treble bleed is designed to work with the modern wiring. The 50's tone pot position only achieves anything by reducing load on th epickup as you roll down volume, which woudl be negated by the treble bleed. But, try it if you think it will be good!

BTW, with 250k pots, I think a slightly better value for the treble bleed resistor is 120k. 150k is good with 500k pots.

Blower
The way you have it, the output stays connected to the volume middle lug, and it would need to have ground lifted to work properly, as you have done. Other wise the volume pot would still load the pickups when set to low volume.

A haven't checked out the blender, but I can't see why you couldn't do the blower in a more normal way, where ground runs through consistenetly and you do a bypass loop with your dpdt switch, one pole to the switch output and the other to the jack hot. In bypass/blower mode, they connect directly togther and in nornal mode, they go via the tone/volume circuits. Blending would be unaffected.

more later.

John

[JohnH]

I had a look at your blender, and i think it will work as you expect, but it could be simplified if you wish:

On the blend pot, you are using the correct lugs. That's so a normal audio taper pot will give you the best response, giving the flat part of the taper as you approach full blend, then resistance increasing faster as you turn up to 10, then disconnecting. So full blend is at 0 and no blend is at 10. If you are buying a no-load pot, that's the way round they will work. Are you making your own no-loads? I see you note them as having no click.

I put in my bought ones, and although the detent at 10 is not very useful, I do notice that there is no slight scratchy noise as you cross into no-load, whereas my home-made ones do scratch a little while the pot is being moved across the cut in the track. not a big problem though, it is only while moving.

On the 5-way, you used two poles to control the blender. You can use only one if you wish. It does not matter which of the two blender pot lugs is connected to the output and which to the pickup being blended in. the blend pot is just acting as a resistor and it does not know which way round it is. So you can hard wire one (either) blend pot lug to the output from the switch (the blue wire), then use one 5-way pole to select N or B to be blending in.

That leaves a whole switch pole free, for something else down the track - maybe different tone caps according to switch position?

If you connect your blender to the switch blue wire, then you have your complete blended output before the volume and tone, and you can insert your blower switch without having the blend mix affected.

cheers
John

[moosie]

I took the liberty of displaying your diagram so we can discuss it without everyone having to click through to see it.

Thanks newey! Still getting used to the boards, or I'd have done that.

[moosie]

Hi John,

First, very mice graphics. What do you draw with?

Thanks. I use OmniGraffle Pro on a Mac. Had it from some work-related computer network diagramming years ago. I wish I was good/patient enough to add layers showing the circuit flow under different conditions... I find it helps to curse while using it.

I dont think you can mix 'greasbucket' with 'no-load'. The greasebucket circuit does whatever it does using all lugs of a normal pot. If you have a break in the track it can't function as intended. I had these on my Strat, and actually didn't find anything interesting about them, other than that you dont get the mid peak as you approach 0, which I quite like to have. I put in no load to take some load off my humbucker. So Id suggest doing one or the other. Have you had either of them on other guitars?

Can you help me understand the no-load conflict? I thought the no-load was simply a break in the track when on 10, which effectively removes the tone pot from the circuit. This would mean the circuit being bypassed becomes irrelevant. No?

I've never used either wiring before. My goal is for greasebucket to provide clarity when tone is rolled back (jazzy), and no load to provide a clear, wide open sound on 10.

Two other things not to mix (unless you have already tried it and like the result). Treble bleed is designed to work with the modern wiring. The 50's tone pot position only achieves anything by reducing load on th epickup as you roll down volume, which woudl be negated by the treble bleed. But, try it if you think it will be good!

Yeah, I suspected something like that. I really want to try the 50s wiring, so I'll leave treble bleed off for now.

120k treble bleed vs 150k... Good to know. I can wire up 100+22 from stuff on hand, if I do add it later.

haven't checked out the blender, but I can't see why you couldn't do the blower in a more normal way, where ground runs through consistenetly and you do a bypass loop with your dpdt switch, one pole to the switch output and the other to the jack hot. In bypass/blower mode, they connect directly togther and in nornal mode, they go via the tone/volume circuits. Blending would be unaffected.

I'm going to respond to this, to get this post out, and then take more time thinking about your next post.

I tried that initially, but because of the blend nuance, I ended up with some kind of ground loop. Maybe not the right term, but as I traced through what would have been connected, it just didn't look right. I modeled the ground lift after StewMac's JackPot. Of course theirs is a pot/switch combo, and mine is a pot/push-pull, but the common idea is ground lift. I wanted to use a probably better quality pot.

[JohnH]

Jan 23, 2013 18:26:20 GMT -5 moosie said:

Can you help me understand the no-load conflict? I thought the no-load was simply a break in the track when on 10, which effectively removes the tone pot from the circuit. This would mean the circuit being bypassed becomes irrelevant. No?

Thats trues, with a normal tone circuit, which only uses two pot lugs.

But if you look at your greasbecket diagram, there is a 0.1 cap between centre and left lugs, which is in parallel with one side of the track. If there was a break in the track, you would still get the no load operation but part of the action of the greasbucket design, where that 0.1 cap gradually gets shorted out, would be ineffective. There would be no point in having two caps., just use one slightly smaller cap. But it wouldnt be 'greasebucket'

One thing it does do is, if a normal tone control goes to 0, the greasebucket doesnt quite get there, but stops at about 1, due to the fixed resistor. If you like that sound, and dont like the 0 sound, then it could still be good, letting you quickly set a not quite 0 tone setting.

[moosie]

If there was a break in the track, you would still get the no load operation but part of the action of the greasbucket design, where that 0.1 cap gradually gets shorted out, would be ineffective.

Oh... yeah. Duh. I want greasebucket more. I could use a normal p/p pot to take tone out of the circuit, but not sure it's worth the trouble.

Are you making your own no-loads? I see you note them as having no click.

No, I'm lazy. CTS: www.guitarelectronics.com/product/CPC250NL/CTS-250K-No-Load-Guitar-Control-Pot.html

On the 5-way, you used two poles to control the blender. You can use only one if you wish. It does not matter which of the two blender pot lugs is connected to the output and which to the pickup being blended in. the blend pot is just acting as a resistor and it does not know which way round it is. So you can hard wire one (either) blend pot lug to the output from the switch (the blue wire), then use one 5-way pole to select N or B to be blending in.

Yeah, I started out with that, but I didn't understand, and thought it would be max at 0 for one pup, and at 10 for the other, or something funkier. It was very cool figuring out how to accomodate this, but the design will be a lot simpler hardwired. I'm gonna save the drawing, though

That leaves a whole switch pole free, for something else down the track - maybe different tone caps according to switch position?

Good idea.... That empty pole will keep calling until I use it for something.

If you connect your blender to the switch blue wire, then you have your complete blended output before the volume and tone, and you can insert your blower switch without having the blend mix affected.

I don't think so. The point of the blower (as I'm defining it) is to eliminate tone sucking pots from the circuit. Including the blend pot. Or am I just being silly? If the blend pot won't make a difference, is the whole blower mod just as useless?

Really helpful comments. Thank you!

[JohnH]

But if your blend pot is no-load, then you can take it out whenever you turn it to 10

[moosie]

But if your blend pot is no-load, then you can take it out whenever you turn it to 10

Ah yes. Very good.

I've incorporated most of your suggestions and corrections. I left the ground lift wiring in place, as it does the job, and seems like it might be more flexible in other situations. Not sure, but can't hurt.

Thanks for the incredibly quick turnaround on this. Here's the updated diagram: (Note: the final version of the diagram is in the first post in this thread.)

[JohnH]

looks like that will work, good luck!
J