The SPlender Mod - My First Major Project

[ozboomer]

'lo all...

Short update, as my internet is broken until mid-week...

The mod is now working, more-or-less and is pretty good. Will provide details and more photos mid-week.

Many thoughts about the whole exercise...

Laterz.....

[ozboomer]

Here we go, folks.. After a bit of a hiccup with my internet connection, here's the latest installment in the SBlender development saga

3:43 pm 10/01/09, MEL time...

Well, I made some adjustments, as we've discussed, with the 'return' from each pickup being placed where I originally understood the 'ground's of the pickups were supposed to be (or something like that).

Suffice to say, things are working more-or-less as expected(!)... although, the business with the blender pot is still being weird - something like the 'swept' area is too small and I don't have a lot of adjustment, as well as the sound of a dirty track comes through every so often, with certain switch positions selected... and! there's something strange going on when the 5-way is in the old "N" or "N+M" positions... but I think I better just go back and review the design again [14/01/09 edit: which I have done and it's mainly sensible; the blender pot acts like a neck pickup volume control in these positions]

Here are some pictures, anyway:









I'm also unsure about what to post/explain next(!). To go through the combinations of sounds is going to be... longwinded(!); (5-way switch positions) x (blender pot on mid=nothing/full bridge/full neck = 3) x (parallel/serial) = 30 distinct sounds. Pffft! to that and -how tedious- on the ears for people to listen to!... but maybe I'll just do a selection of the sounds I like most, I dunno...

Anyway, even though I've only played about with the modified guitar for only a short time, I think some of these 'findings' might be useful:

• Going to a single tone pot instead of two is definitely worthwhile. It's easier to work, provides just as much control and it's much easier to understand what the heck the circuit is doing
  
  
• Using Mr Clapton's 'woman tone' -style tone capacitor (0.012uF) is the best yet for the sorts of sounds I like. Another strat of mine started with a 0.047uF, which I changed to a 0.022uF, which was better. Using the 0.012uF in this mod is the best so far, I think (at least with the 500k pots)...
  
  
• The "volume bleed" is also very worthwhile. Although I'm not in a situation where I frequently need to instantly change volume, I can see that it would be very useful to be able to.. and still maintain the tonal quality of the guitar's sound.
  
  
• The cavity shielding didn't seem to make a big difference in this case, although using the shielded pickguard DID seem to make quite a difference (but then, I think the ceramic pickups I've been using were pretty quiet anyway). I probably wouldn't go to the trouble again of doing the cavity shielding... I'm no professional player and I don't really *need* to have the guitar super-quiet... but I *would* do the pickguard (which was the only shielding I was going to do originally with this project anyway!)
  
  
• I wouldn't worry about the blender pot, myself. I think it would be sufficient to simplify the whole thing and just go for a "neck-on" switch (or , even better, the alternative "bridge- on" mod, as that provides a tone control, with no other changes being made to the stock wiring).
  
  
• The serial switching would be good to investigate another time; even to think about a humbucker in the bridge position and maybe doing coil taps, etc. Switching into serial connection between the pickups gives a great, fuller sound (but I've yet to try the "crunch" side of things - I mostly like playing clean).
  
  
• Doing this design was kindof ambitious and for the time and effort involved, I don't think it was really worth it (for me). Then, I'm only a hack, playing at home... and I would normally play electronics with circuit boards, etc... and I'm not really that avid an experimenter, hardware-wise... and when I DO get out the soldering iron, I'm not really interested in doing a lot of "spider work" inside confined spaces
  

As always, these are my OWN views... 'your mileage may vary'

Anyway, let me just say Fanx! again for everyone's help. It's been a HECK! of a project to work through.. but I think I've found out a lot of useful info for the next time I feel like tinkering

Some example sounds to follow in the next few days, I hope...

[JohnH]

Congrats on getting to the end. And nice pictures too.

I'd like to know more about how the blemder is working, since it sounds like it is a bit dissappointing. In series mode, in the bridge position, you should get a full smooth sweep from bridge to neck, with the most interesting blended sound IMO, being bridge with just a small amount of neck. Also, Ive forgotten what pot value you used for the blender, and log or lin, and did the track get cut?

cheers

John

[ozboomer]

Jan 14, 2009 6:11:36 GMT -5 JohnH said:

I'd like to know more about how the blemder is working, since it sounds like it is a bit dissappointing. In series mode, in the bridge position, you should get a full smooth sweep from bridge to neck, with the most interesting blended sound IMO, being bridge with just a small amount of neck.

Probably more relevant, is the fact that I'm a bit of a hack player and can't appreciate the subtle differences(!) as much as some people, as I can't play well enough to "make the sounds shine", even though I can hear the differences in the sound/tone

Anyway, I've tried what you mention there... and ya, it seems to blend that way Ok... but we have something of a very "nasal" sound at 0 through 1 or so... that goes to a slightly more mellow sound at 2... and then doesn't change too much by the time we get to the middle of the pot, where the track was cut... then we get a much stronger "mellow" sound as the neck pup is brought in. I'll try and do a recording of that particular transition...

Jan 14, 2009 6:11:36 GMT -5 JohnH said:

Also, Ive forgotten what pot value you used for the blender, and log or lin, and did the track get cut?

Yup. 100k "B" taper (linear?) - you can see the markings in some of the photos - ... as I couldn't get a 250k that would suit the Fender knobs.

On that... I think the higher value would probably have been better. The 500k pots track really nicely on the volume and tone... and I got those pots from my tech... but the 100k was only a Dick Smith thing and it's nowhere near as smooth in how it turns... Pffft.

...and ya, the track was surely cut - again, shown in some of the early photos - but maybe I was a bit savage with it -- there's no carbon track from 10 o'clock through to 2 o'clock... so it might have been too drastic a cut, especially since it's only a 100k pot...

[gitpiddler]

Nice pics oz. You've got a lot of green ground wires that could go away. My philosophy is to keep signal ground separate from shield ground, especially that little wire from the vol. pot case to the ground terminal. Ideally, the bridge ground and the shield grounds should connect to the jack ground separate from the signal ground to the vol. pot. The pickguard shielding should be enough to connect the p'ups, switches and pots without the extra green wires. Nice work mate.

[ozboomer]

Well, I'm having all sorts of adventures with the mod tonight...

Firstly, I assumed the functional description was complete/correct for whatever I constructed(!) - here it is extracted for easier reference:

Where "+" means a parallel connection and "x" means a series connection between pickups.

Parallel mode:
Standard 5 Strat settings with the option to blend
in the neck with B, B+M or M tone control works normally

Series mode:
Blender in mid position:
BxN, (B+M)xN, MxN, N, N, all with 'full signal' neck pickup.

Blender towards bridge:
BxN, (B+M)xN, MxN, N, N, all with 'reducing signal' neck pickup

Blender towards neck:
BxN, (B+M)xN, MxN, N, N, all with 'reducing signal' bridge pickup

Tone Control:
Full signal/full treble at 10... reducing treble as the pot is turned towards 1

So I went ahead and recorded a sound sample for each of the 5-way switch/blender positions; so that would be something like: (series/parallel) x (pos. 1-5) x (full CW/middle/full CCW blender) = 2x5x3 = 30 sounds... and it came out to 10 minutes or so... which is pretty awful to listen to in one hit.

So, as I was thinking about how to present/combine these sounds in a meaningful/comparable way, I made a discovery or two...

With the DPDT switch in the parallel setting, we get the familiar Strat sounds but we can also blend-in the Neck pickup in parallel, where nothing much happens from fully CCW to the mid-position on the blender... but from the mid-position to fully CW, we can hear the Neck pickup being added-in and this seems to happen in the conventional B, B+M and M 5-way switch settings. The other two settings of the 5-way seem to only include the "full" Neck pickup sound.

The really interesting things seem to happen when the series setting is selected on the DPDT...

B:
full CCW = no series Neck
CW rotation = increasing series Neck
mid = max. series Neck
more than mid = no change through the range

B+M:
full CCW = no series Neck
CW rotation = increasing series Neck
mid = max. series Neck
more than mid = brightening tone OR
no change through the range
(I find it hard to tell)

M:
full CCW = no series Neck
CW rotation = increasing series Neck
mid = max. series Neck
more than mid = I can't hear any difference
throughout the range

M+N:
full CCW = no sound
CW rotation = increasing series Neck
mid = max. series Neck (not as much as previously)
more than mid = just the (series?) Bridge

N:
full CCW = no sound
CW rotation = increasing series Neck
mid = max. series Neck (not as much as previously)
more than mid = just the (series?) Bridge

So, I really don't know what to make of all this... Remember to keep in mind that we have a pot with the centre of the carbon track removed (10am - 2pm) for the blender pot.

Suggestions, please, on:

• Do we need to re-read/re-work the circuit?
  
• What about the 'definitions' of how the circuit works?
  
• Give it away until someone else tries the mod out?
  
• What I need to post to show you the way this thing sounds?
  

Fanx! folks...

[JohnH]

Hi Oz - there could be somerthing amiss here, because in series mode, with bridge set on the 5 way, you should be able to get, as you sweep the blender:

full bridge - full bridge plus increasing neck - full bridge plus full neck at mid point - full neck plus decreasing bridge - full neck no bridge

whereas you seem to not be getting a change past the mid point

also - just to help keep track - Im sticking a link to the schematic here
guitarnuts2.proboards45.com/index.cgi?board=schem&action=display&thread=3607

John

[ozboomer]

Hi, Mr John... and everyone...

Well, before I go and trash another perfectly good set of strings to do some more investigating, is there anything you can think of that I should be looking for that will indicate where the dramas are? I mean, should I see some common (equal) resistance values at some points in the circuit?

!! Something I just found while writing this note... It seems there might be a drama with the position of the 'ground screw' I have in the cavity. Have another look at this previously posted photo, noting the location of the 'ground screw' and how far it is from the rear of the cavity:



Now, whether it's contributing to the current blending problems, I don't know (grounding of a pickup?)... but the height of the bridge pickup cannot be adjusted; if I turn the height-adjusting screws, they just come out rather than lowering the pickup... So, I think the bridge pickup is pressed hard against the ground screw... or at least, something's jamming something there... If/when I take the pickguard off, I'll do something about the location of that screw, for sure... but I wonder if that's a clue -- something being shorted to ground would make the blender work weird...

Any further thoughts, to help persuade me to 'go back in'? ;D


Another John

[JohnH]

Yup - a couple of things to try, set to series mode

Do some tests where you plug into an amp and tap the pup pole pieces with a screw driver - to see exactly what is active. Big click if a particular pup is switched on, or just a very small or no click if not active. You could do that to check what pups are acting at various points of the blender sweep.

Sweep the blender, with 5way set to b and max volume, and record total guitar resistance through the output jack at 0 1/4 1/2 3/4 and full blender turn. You'd be looking for a resistance that starts at a bit less than one pup resistance (ie, one pup is active, the other is shunted by blender), rises to a bit less than twice that at blender mid point (ie two pups in series and not bypassed), then returns to just under one pup resistance. The 'just under' part comes from the volume pot being in parallel with the pups.

John

[ozboomer]

Well, this was an enlightening exercise...

As suggested, I tried the 'pickup click tests' and here are the results:

The parallel combinations are more-or-less no surprise... but the series connections seem to highlight some sort of drama. It looks like the neck pup is almost always in the circuit, no matter what the position of the blender... except when it's up at the fully CW end of its run... and how the middle pup is getting in there when it's not 'connected'... well, this is just a mess to me.!?!?

As far as the resistances go, we seem to get what's expected. As JohnH describes, I set the DPDT to the series setting, the 5-way onto the conventional 'bridge only' position and volume pot to maximum... and here's what I found through the output jack:

Blender Pos.

1

[td]3

[/td][/center]

[td]5

[/td][/center]

[td]7

[/td][/center]

[td]10

[/td][/center][/tr]
[tr][td]Resistance[/td][td]8.3k[/td][td]14.0k[/td][td]16.5k[/td][td]14.5k[/td][td]8.4k[/td][/tr][/table][/center]

So, that also seems sensible.

...but where in da heck are those 'click' results coming from!? ...and what steps do they indicate we should follow next??

[JohnH]

Well thats a puzzle!

Your resistance measurements check out very well, even the 1/4 and 3/4 settings, based on your 100k blender.

My nearest equivalent guitar, which used to have a similar blender, had to reluctantly sacrifice it to make way for a piezo blender. However, I still have the series/parallel options and now the previous function of the blender is replaced by half the 5-way. So I had a listen to these clicks in equivalent series settings, and although sometimes the dead pickups still give a vestigial click when fully turned off, it is much reduced. In the 1/4 settings, what sounds as a much reduced contribution from a pup can still give quite a big click with the screwdriver.

So it looks like there may be some anomaly between the resistance settings and the sound output. Another way to tell pickup activity is a screwdtriver pulloff test - with an analogue multimeter set to the lowest volts setting. Place blade of screwdriver on pickup poles and lift up quickly to make the needle jump if it is active. You wouldnt happen to have one of those lying around would you?

I wondered if the resistance readings were a fluke, and are appearing correct by chance but with some wiring anomalies. Even with your good photos, its still very hard to check wiring connections. But looking at the views on the 5-way switch, some of the connections which I thought would be the neck look like they would be to the bridge. Usuall the lugs at the back of a 5-way have those for the neck at the end nearest the bridge and vice versa etc, due to the physical switch construction. If you wish to persue, perhaps you could make a pictorial diagram showing the 5-way lugs and what they are connected to, and also the S/P switch.

and happy Australia Day!

John

[ozboomer]

Just a quick note on this, as I'm in the middle of a very 'Australia Day'-like activity -- bill purging! ;D

Jan 25, 2009 17:26:20 GMT -5 JohnH said:

...Another way to tell pickup activity is a screwdtriver pulloff test... ... You wouldnt happen to have one of those lying around would you?

Natch! My DMM is about 25 yo anyway, let alone how old the analogue is... but I'll give that a go in a lil' while...

In short, I'm almost at the stage of leaving this design go and accept that I have a circuit that, like most of us, has its idiosyncrasies. At least I have a better idea of how some of these settings (might/should) sound... and I can get another loaded pickguard and try a couple more SIMPLER tweaks... as I develop the (electronic) specs for my Preferred Strat Circuit

More later... and Fanx! for the on-going help


-John

[ozboomer]

Well, I'm confused..

I have an open-shelled 1/4" phono plug in the output jack... and my analogue meter is set to the lowest DC Voltage range (full-scale = 0.6V) and the meter has a new battery in it... The probes are installed in the correct places on the meter and I have them attached to the shield/ground and the hot of the phono plug. The DPDT switch is set to parallel (so we should get normal Strat behaviour), and the 5-way is set to the conventional 'bridge' position.

Now, if I tap a pole on the bridge pup OR if I let the screwdriver sit on the pole and then pull it away quickly, I get no deflection on the meter. I try using a battery and a resistor and the meter actually -works- ... but blowed if I know if I'm doing the right thing with the meter on the guitar?!?

[JohnH]

The pull off test is a straight, quick lift of the flat side face of the screwdrivertip, up off the pup pole, on a dc volt setting. But maybe your meter is not very sensitive, Id have thogh it would give something though. Oh well, Im out of ideas!
John

[ozboomer]

'lo all...

Well, I had another go at the 'deflection test' with the analogue meter... and this time, I used a big screwdriver... and o'course, things worked this time -- Haveta get that flux big enough, eh?? ('...it's the rate of change of magnetic flux...' -- Boy! was THAT hammered into my head in Form 5/Year 11!!!) The deflection is generally about 0.01V or less, so it's pretty tiny...

Anyhoo, here's the results of this 'deflection test':

So, does that look any better? ...to match what we think should be happening?? Mr John? Buddy... pal... mate...

[JohnH]

From that test, they all seem to be what you'd expect from the design - do you agree?

So I reckon you have it built the way you intended after all. You have the 5 basic tones, plus neck-on in parallel, and the series settings too, so at least you can decide what you think of it all.

There might be some mileage in winding up the level of the bridge with the setting screws, and putting the neck down, to try to get more balance between them.

Well done, at least its a learning exercise!

cheers

John

[ozboomer]

Hidy-ho, everybody... ( with thanks to Jack Davey, for all you oldies )

johnh said:

From that test, they all seem to be what you'd expect from the design - do you agree?

Well, I thought so... Just that it sort of sounds a bit weird at the moment, probably 'coz the blender pot is 'cut' a bit strangely or maybe unevenly.

From what I understand, the pup height can be a critical adjustment and is something I've not fiddled with at all on this current project... but with the weird angle on the bridge pup that I described in a previous post, I guess it's time to open everything up and get THAT resolved. Once that's been done, I can put everything together and do a 'proper'/complete setup on the guitar -- another learning exercise for me

Anyway, this still leaves the question of the multi-element sample recording I did the other night. I still think 30 samples is too much to listen to... Thinking about it a bit, I think the following combinations would probably give a pretty good idea of the 'extreme' changes in sound we can get with this modification:

Let's know your thoughts (any- and everyone) for the options to record and I'll post something to listen to during the week.

[JohnH]

Those would be good to hear. Another simple one if you are taking requests: a chord strum, with a sweep of the series blender from B to BxN to N, while the chord rings.

John

[ozboomer]

Howdy, folks...

I've managed to get my head around the options and how they work a bit tonight... So, here's a summary:

So, for example, let's look at the first line... If the parallel/series toggle is set to Parallel and the 5-way switch is set to 'bridge position', when the blender is swept from 1 to 5, all we hear is the bridge pickup at maximum level. However as the blender is swept from 5 to 10, the level of the neck pickup in the output goes from 0 to maximum... and so it goes through the rest of the combinations.

Sorry I missed your post earlier, JohnH -- but let's describe your request as another example: Set the toggle to Series, the 5-way to 'bridge position' and start with the blender on 1. Striking the chord then would give us a sound of all bridge pickup only. As the chord rings, we'd sweep the blender, gradually bringing in the neck pickup in series until we got to the 5 position. As we sweep through 5 and head to 10, the bridge pickup will be faded out. Now, as mentioned earlier, the pickup heights are not... 'optimum'... so we may not hear the sounds quite the way you would like... Nevertheless, here's an example:

SPlender_Request_JohnH_Jan09.mp3

Now, to give a demonstration of the 'extreme sounds' as detailed in my last post. There were 10 sounds mentioned and I have created a few files to demonstrate these sounds (as best as I'm able!). Just as a reminder, here they are again:

So, we have the 'bridge' sounds (B, B+N and BxN):

Squier_Bullet_SPlender_01.mp3

...the 'bridge and middle' sounds, B+M, B+M+N and (B+M)xN:

Squier_Bullet_SPlender_02.mp3

...and the 'middle and neck' sounds, M, M+N (via blender), MxN, M+N (conventional) and N:

Squier_Bullet_SPlender_03.mp3

Hopefully, this will give you an idea of how things sound - apologies for the occasional squeak and squawk in the recordings - I dunno where they came from. I might do it all again once I've done the setup and adjusted the pickup heights... but it's all new to me, so maybe I'll get it all wrong

Let's see where this goes now, eh?

Fanx! again to everyone for the interest and support. It's been a great project to get through


-John

[JohnH]

Thanks for posting those - I think the series settings are showing a nice thickening of the sound, and you can hear the changes happening as you go through the blender sweep, with the ends of the range being just one coil and having more edge, but the central series setting being fuller.

cheers

John

[newey]

Yes. a very nice job, ozboomer! Please stick around when you're not too busy playing your new creation.