Building a Wal....ish

[LukeFRC]

43 minutes ago, NickA said:

I'm really suprised that the pick attack is derived from the neck pickup; I'd always assumed it was from the sum of both or maybe from the breidge (which is the default in the ACT=EQ-01).

Interesting - I had a ACG EQ1 and started it with the high filter  from the bridge and after playing with it a while ended up with it on the neck pickup (on a Warwick SS1 so probably not a million miles away from Wal position, if not a different style of pickup) 

[mhoss32]

@Kinkh Thats some ace work on the schematic, A really useful piece of work for anyone looking into this. 

 

@funkle, as you mentioned, the way i went about the "pick attack" feature is very similar. 

 

 

On the filter board (right) there are 4 output pins on the right hand side:

 

1. OUT (the filtered signal)

2. GND ( ground)

3. VB (biased voltage to pass to the volume board)

4. P/T (a clean passthrough signal from the pickup)

 

These then feed into the volume board (on the right). when the volume pot is pushed in, the filtered signal is passed straight to the pot, so it acts as a normal volume control. when it is pulled out, it blends the filtered signal with a second signal, which is the P/T signal that is then Low pass filtered and boosted. the level of each of these 2 signals and the overall boost can be changed using the 3 trimpots on the board.

 

the picture above is actually an older prototype, the newer version only has 2 red mini switches on the volume board. these can be changed to change the frequency of the peak for the pick attack mode:

 

OFF - OFF - 1.5kHz (sharp peak)

ON - OFF - 2.2kHz (sharp peak)

OFF - ON - 2.1kHz (shallower peak)

ON - ON - 3.5kHz (sharp peak) 

 

From your simulations in LTspice, it looks like the Wal boost in attack mode is much broader than the one in mine, but centre looks around 3.5Khz

 

I got some great feedback from both @Andyjr1515and @benh, who have prototypes, so im still working on these. 

 

In terms of layout though, separating out the boards does provide some extra flexibility in terms of setup. using a single volume board, you can run the P/T pin (for the pick attack) from either the bridge pickup or the neck pickup, or have a switch to switch between them!

 

The idea behind these was to make the system as customisable as possible, so the user can have a very simple setup similar to a wal (push pull for resonance on the frequency pots, and push pull pick attack on the volume), or add in additional controls if they want more tweakability like on ACG's preamps. below is a normal installation: (note the "jumpers" on the pins at the bottom corners of the board")

One feature that can be useful for example is having additional settings for the resonance (such as ACG/Alembic filters). when the jumper is in place, the push pull is simply Low/High. but the jumper can easily be replaced by a 2 position switch, 3 position switch or pot for variable resonance:

 

 

There are also pins / jumpers to change filter modes but that's even more complicated. sorry for the low quality JPEGS here btw, these are snips from my first draft at the instructions for these preamp boards. 

 

Id say that based on the plots you put up, it wouldnt be too difficult to simply much about with frequency values on these boards to replicate those plots very closely, although as you say im not certain whether some of the character comes from the somewhat outdated component choices. If @Kinkhdoes go ahead and build an exact copy of that schematic, ill certainly send one of mine over with matched frequencies to compare!

 

 

Honestly the work of people on this forum never ceases to amaze me!! amazing work and can't wait to see the build progress!

[Passinwind]

On 30/07/2022 at 08:21, Kinkh said:

I remember that there was a way to take a .wav file as an input in LTSpice, pass it through the circuit, and record the output as a .wav.
I may have done that once more than 10 years ago, so I currently have no clue how to do that anymore... But, it might be the "best" way to see how something sounds when passed through one of these circuits.

I've done that many times, on my computer the render time is extremely slow. https://www.allaboutcircuits.com/technical-articles/ltspice-simulation-using-wav-files/

[NickA]

On 31/07/2022 at 23:10, LukeFRC said:

On 31/07/2022 at 22:25, NickA said:

 

Interesting - I had a ACG EQ1 and started it with the high filter  from the bridge and after playing with it a while ended up with it on the neck pickup (

Oh no! Now I just have to start fiddling about with my bitsa project bass again. Screwdriver time.

[NickA]

.... Though I realise it does make sense as the only way I can get a decent slap tone out my mk2 Wal is to bias the mix knob towards the neck pickup ( and pull all the knobs out) ... the neck pickup is where the twang comes from.

 

whereas my Warwick dolphin has twang coming from everywhere and is clearly the better slap bass even before its plugged into an amp.  I have no idea why.

[Andyjr1515]

Well, the neck seems to have taken ages...

 

...but definitely on the home straight.

 

This last couple of days has been the fret levelling, re-crowning and polishing.  For levelling - after adjusting the truss rod so that we are starting off with a straight neck - I start with my length of aluminium bar with emery cloth stuck to it:

 

The filings (seen here above as grey patches) are the guide to whether all frets are being touched by the beam, and thus all fret tops are level with each other.

 

But, of course, now all the frets have flat tops to a greater or lesser extent.  So then you need to re-crown them and polish them.  This is what I use:

 

 

I use the little Chris Alsop diamond crowning file, first to round the ends and the rough crown along the length.  Then I wrap emery grades, then finer and finer grades of micro-mesh round the crowning file to round any remaining flat points and to progressively take out the scratches.  I use 240/400/800 emery, followed by 3200/4000/6000/8000/12000 grit micro-mesh.  I find it easier to do one fret at a time and walk the couple of strips of masking tape up the board as I go.

 

Here is 1 done and 19 to go  :

 

And all done:

 

So that just leaves the filling of the fretboard side slots, cutting the nut and fitting the tuners.  All being well, that will be all complete by the end of tomorrow  

 

 

 

[Andyjr1515]

And - it's take a long time! - the neck's done 

 

 

 

I managed to find a mist overspray that didn't melt @funkle 's decal !

 

 

I haven't fit the hipshot-like string tree that @funkle sent to me as the three slots were narrower than the string spacing of the 1.5" nut and it would squeeze the G and A towards the D a touch.

 

So - at last, ready to ship  

 

 

 

[Tom Stafford]

Loving the thread!

 

I am currently putting together a (lefty) Stingray/Wal - have got a body (mahogany w/walnut top) and neck being made up atm with custom MK1 pickup spacings, and I plan on putting Herrick multicoils and LusitHand electronics in there.

 

All the info here has been amazingly useful. Just wondering what peoples thoughts on bridge choice would be?

[Lfalex v1.1]

Whilst I can't think of a specific unit,  to my mind, bridges ought to allow the usual adjustment for string height and intonation plus string spacing; The latter being relevant as you'll be wanting good string alignment over the coils.

Lockable saddles would be a plus, as would a very secure attachment to the body. 

 

Edit- having looked at the original units, I note a Stingray- like 5 screw attachment (2 either side and 3 to the rear)

There's also the horseshoe- shaped casting. Even if the saddles aren't lockable  it'll limit side-to-side movement. No provision for spacing adjustment is provided. 

 

The nearest thing I can see is actually a G&L bridge. They even come in black with bare metal saddles.

 

Downsides?

They'll be stamped with the G&L logo.

They take imperial Allen keys.

They require the body to be routed to fit them- They're not surface mounted as such.

Edited August 19, 2022 by Lfalex v1.1
More ideas

[luthifer]

On 30/07/2022 at 05:41, funkle said:

It’s fascinating. I guess the only way to know for sure is to build a ‘modern’ version of the circuit and see if it sounds similar. 
 

Perhaps though, @mhoss32or Nuno from Lusithand have basically done this already. Or the Underhill chap. With their own twists. 
 

I am interested to see that that circuit is apparently relatively even in the low end and low mids until you sweep the filter down there. 
 

That largely leaves the pickups, the neck, or the body, or a mix thereof, as the source for the low mid boost that Wals seem to enjoy.  
 

The neck should be ready soon…

 

Underhill chap here!  Nice to get a look at the circuit, thanks for the work Kinkh. What jumps out at me is the deliberate phase reversal of the pick attack. It makes sense since the phase above cutoff is also reversed? The Q switching scheme is also not what I expected!

[Tom Stafford]

On 18/08/2022 at 15:47, Lfalex v1.1 said:

Whilst I can't think of a specific unit,  to my mind, bridges ought to allow the usual adjustment for string height and intonation plus string spacing; The latter being relevant as you'll be wanting good string alignment over the coils.

Lockable saddles would be a plus, as would a very secure attachment to the body. 

 

Edit- having looked at the original units, I note a Stingray- like 5 screw attachment (2 either side and 3 to the rear)

There's also the horseshoe- shaped casting. Even if the saddles aren't lockable  it'll limit side-to-side movement. No provision for spacing adjustment is provided. 

 

The nearest thing I can see is actually a G&L bridge. They even come in black with bare metal saddles.

 

Downsides?

They'll be stamped with the G&L logo.

They take imperial Allen keys.

They require the body to be routed to fit them- They're not surface mounted as such.

Annoyingly I can't seem to find a dealer for the G&L in the UK, and routing the body might be a bit of a faff... Currently looking at either Babicz or Schaller 3D-4 (though I'm not sure if the latter is lefty friendly due to the width of the rollers, not sure if anyone here who has one can confirm how hard it would be to swap those around?)

 

On 19/08/2022 at 16:16, luthifer said:

 

Underhill chap here!  Nice to get a look at the circuit, thanks for the work Kinkh. What jumps out at me is the deliberate phase reversal of the pick attack. It makes sense since the phase above cutoff is also reversed? The Q switching scheme is also not what I expected!

On a separate note this is really interesting! My Lusithand pre just arrived, but the design doesn't have a pick attack mode, just a boost in the resonance of the cutoff. I'm wondering how tricky it would be to implement, its made slightly trickier by the fact that the circuits are gooped and that my pickups are wired new way 1HBPS... Might message Nuno to see!

 

The rest of my build isn't looking like its going to be finished for another month or so so going to have to wait to hear how it all sounds. Will post some sound clips when its up and running though!

[NickA]

Schaller 3d on my project fretless, nice bridge.

 

You're right that it won't work left handed though, the roller grooves are different widths.  However, the threaded bars the roller are fitted to are only press fitted into the saddles, maybe you could press them out and swap around. 

 

Tried on mine and they didn't come out with the force I was prepared to use ( very little, and the bridge is near 40 years old and ceased up a bit! ) But brute force would do it I reckon.

Edited September 9, 2022 by NickA

[Owen]

I cruelly besmirched a bass bridge in this post. I got it wrong. It was another manufacturer. I am sorry. It was not a Schaller.

 

Sorry for messing up your post below BRX.

Edited September 9, 2022 by Owen

[BigRedX]

3 hours ago, Owen said:

I had a Schaller 3D. It just disintigrated on me. It seemed to be made of cheese. YMMV.

 

Probably not a real Schaller then. I had a Hondo Alien Bass that came with look-alike fitted that exhibited exactly what you have described.

 

IME the real ones are almost indestructible. There was one fitted to my mid-80s Overwater that was still working fine when I sold the bass a few years ago.

[luthifer]

On 05/09/2022 at 04:03, Tom Stafford said:

Annoyingly I can't seem to find a dealer for the G&L in the UK, and routing the body might be a bit of a faff... Currently looking at either Babicz or Schaller 3D-4 (though I'm not sure if the latter is lefty friendly due to the width of the rollers, not sure if anyone here who has one can confirm how hard it would be to swap those around?)

 

On a separate note this is really interesting! My Lusithand pre just arrived, but the design doesn't have a pick attack mode, just a boost in the resonance of the cutoff. I'm wondering how tricky it would be to implement, its made slightly trickier by the fact that the circuits are gooped and that my pickups are wired new way 1HBPS... Might message Nuno to see!

 

The rest of my build isn't looking like its going to be finished for another month or so so going to have to wait to hear how it all sounds. Will post some sound clips when its up and running though!

I'm working on a "pick attack", I'll have something this year. It's not hard to implement; more a matter of testing different designs for sound qualities, and deciding exactly how to fit it into the modular scheme. Right now I'm testing a filter that can function similar to the Wal (in the schematic above) but a different topology that can do other things as well. My goal isn't to copy a Wal, but it should sound pretty close when tuned the same. 

[funkle]

17 minutes ago, luthifer said:

I'm working on a "pick attack", I'll have something this year. It's not hard to implement; more a matter of testing different designs for sound qualities, and deciding exactly how to fit it into the modular scheme. Right now I'm testing a filter that can function similar to the Wal (in the schematic above) but a different topology that can do other things as well. My goal isn't to copy a Wal, but it should sound pretty close when tuned the same. 

That’s great news. Can’t wait to hear it!
 

I have lived with the Lusithand pre for a while now and really like it. I do miss the bright switch though.
 

I’m sorry about the lack of videos recently, there were family deaths that I had to deal with, which have taken most of this year to sort the fallout from. But I have plans for 2 presently. One with the Lusithand preamp, and then the next with Andy’s neck and the Lusithand preamp. Then I plan to sort out a mahogany body, depending. 

[Tom Stafford]

I'm wondering if I could potentially take the signals of the Lusithand filters pre-blend, split them off and implement the HPF of the Wal circuit and then blend them back in for a makeshift attack switch. Wouldn't quite be the same obviously and would require one of the filters to be completely open at any time in order to work but I might have a poke around on my breadboard if I get a minute.

[skelf]

My main preamp as in the one I use in my own basses the DFM. It has the pic attack feature activated by one of the two push/pull functions. There is a choice of two frequencies on each push/pull set internally along with the gain. 

[fauxtoe]

Hello everyone! I have followed along with this thread silently as @funkle and I have conversed on TalkBass about building Wal-ish basses. For those of you who might have planned to use anything from Rautia, he just put out a message today that his business is now shut down - "THE SHOP IS CLOSED. THANK YOU SO MUCH TO ALL MY CUSTOMERS. 36 YEARS OF GUITAR WORK BEHIND, THE LAST 10 YEARS MAINLY PICKUPS. NOW SOMETHING ELSE...."  

 

I put a set if his pickups in my "Jazz-Wal" hybrid bass and they are everything that I could have ever hoped for with that build, so it's unfortunate we are now down one less multi-coil builder in the world.

[TrevorR]

4 hours ago, fauxtoe said:

so it's unfortunate we are now down one less multi-coil builder in the world.

…and the best maker of Matsumoku era Aria SB bass pickup replacements too… 😥

Edited November 15, 2022 by TrevorR

[Tom Stafford]

Sting-Wal body and neck have finally arrived! Stupidly forgot a few parts so will be a week or so before I finally plug it in…

 

Also slightly nervous to take a drill to it to mount everything so might take it to Denmark st…

[funkle]

Be very interested to hear how Herrick pickups work out. 
 

I was literally videoing the Wal-ish bass today with the Lusithand preamp. Messed up some technical things with a new setup so will re-shoot. Suffice it to say that I like the Lusithand preamp a lot, and the Turner pickups seem faithful to me, after living with them for a long time.  
 

 

Edited November 29, 2022 by funkle

[funkle]

Ok, finally got my act together and re-shot video, after the first version I did had technical issues. Then re-edited, and uploaded, etc.

 

This one focuses on the Lusithand preamp. I like it a lot. Kudos to Nuno for sending it to me to try it. It's staying in for now unless someone else can convince me they get the 'grit' it provides. 

 

I'll get to adding video timestamps tomorrow. 

 

 

Edited December 10, 2022 by funkle

[Kiwi]

Sounds great!  I need to check if Turner do 5 string soapbars. 

[LukeFRC]

That does sound brill! You’re getting closer