Building a Wal....ish

[Richard R]

Just now, Richard R said:

But where's the fun in that? Especially for us spectators. 😉

 

Oh of course, the fun is in playing the damn' things. 

[funkle]

1 hour ago, Richard R said:

 

Oh of course, the fun is in playing the damn' things. 

Very true….but not for £10k….a line has to be drawn somewhere…

[NickA]

Worry not, I'm enjoying it too.  But my personal solution only cost £850 which was a lot less than I was heading towards in experimentation.  Different today.

[funkle]

Ok, an update. 
 

Living with a Wal for a few days has been quite instructive. 
 

First of all, I have to admit I am nowhere near the sound of the Wal. The test bed I currently have sounds beautiful and balanced and even with a relaxed mid range by comparison; the Wal is incredibly mid forward yet somehow still has reasonable top end, with the pick attack adding valuable clarity. I will say swapping to a rosewood neck helped a lot and nickel strings were helpful too, but I’m just not there. Although these pickups I have sound great!
 

So there’s that. 
 

Secondly, the Wal preamp is really well thought out. Enough control to be meaningful but not overwhelming, and I understand how to use the system reasonably after practice. There are a lot of sounds in there, and the mids can be tamed back if desired. It’s a really good preamp. Just a comment in passing. 
 

Thirdly, the neck is very stiff. Much stiffer than a typical Fender neck, and I can recall other basses I have tried with multi-laminate necks with maple/mahogany which are super strong in the mids. (Some of the Yamaha basses in particular come to mind.) At any rate, the exact same set of Slinkies, same gauge, with same relief and action, feels very different on the two basses. I know the tension must be the same, because physics, but they do not feel the same at all. I found this really surprising. On the Wal, the Slinkies feel really stiff and taut; on the test bed, flexible and easier to bend. 

My conclusion, rightly or wrongly, is that the stiffness of the neck must have a significant part to play in how the strings feel/vibrate, and therefore affect the sound. So perhaps the multi-laminate build to the neck contributes even more than I thought. 
 

I am pondering the next steps. I have several working theories:

 

1. It may well be the pickups I have now, which have 8000 winds per coil of 42 AWG wire, but otherwise mostly stick to the Wal recipe, are just naturally more balanced pickups than the Wal ones. I am reminded that even passive Wals with no preamp have ‘the Wal sound’. This could be tested by finding another maker to make pickups even more exactly to the Wal recipe - Rautia or Aaron Armstrong. £££

 

2. The pickups may be fine, but it could be the neck construction gives more mids than I had realised. This could be tested by building a multi-laminate 5 piece mahogany/maple

neck. (Less expensive than a pickup change!!)

 

3. The pickups and neck are fine, but the preamp is not flat and does a significant amount of tone shaping that I am unaware of which comes into play before the manual tone shaping. I don’t think this is right; I will cite the examples of passive Wal Pros still having the Wal sound as being against this theory. 
 

I also still have the Lusithand preamp to try out which is as yet an unknown quantity to me. 

 

I’ll contemplate the next steps. I do want to try the Lusithand preamp next. I’m not sure of the value of recording now given how far off I think I am, when comparing in real life. 

[Owen]

I was discussing the ACG filter preamp with Skelf the other day (as you do) and, for the record, he said that it has no baked in tone. 

[funkle]

Thanks @Owen

 

Yes, the ACG is flat, Alan was clear that the design was clean and clear and flat when I spoke to him as well. I really like the ACG EQ-01. 
 

What I’m not sure about is whether the Wal preamp is flat or not. I might have not made that clear in the last post; apologies; it was rather long…

[Owen]

1 minute ago, funkle said:

Thanks @Owen

 

What I’m not sure about is whether the Wal preamp is flat or not. I might have not made that clear in the last post; apologies; it was rather long…

Nope, it was entirely clear

[Kiwi]

8 hours ago, funkle said:

My conclusion, rightly or wrongly, is that the stiffness of the neck must have a significant part to play in how the strings feel/vibrate, and therefore affect the sound. So perhaps the multi-laminate build to the neck contributes even more than I thought. 

I think playability is all about the neck.  Later Wal necks also have a secret laminate of graphite under the fingerboard which contributes to stiffness, in addition to the wood laminates.  If anything the wood in a bass neck dampens and filters while the fingerboard provides rigidity - Vigier necks are a great example of optimal rigidity (90/10 system plus phenolic fingerboard) while still allowing enough wood in construction to provide some character via dampening and yes, they have a very mid prominent sound.

 

However I've found that beyond about five neck laminates can tend to homogenise the sound.  Of course there are exceptions like the Warwick Thumb which uses a highly unique combination of wood laminates but a load of boutique basses out featuring combinations of walnut, maple, purpleheart and mahogany in seven laminates (along with laminated bodies) sound more or less the same as one another, regardless of electronics.

I've long maintained the view that making musical instruments is a lot like a recipe - the ingredients require balancing against one another for an appetising outcome.  In the case of necks, there's a balance in construction for playability vs construction for timbre vs construction for convenience.  Some structural in-efficiency helps add character, too. 

Graphite necked basses are not all alike, either.  Some, especially the early ones from the late seventies/early 80's, are over designed and I like how most of the dampening comes from body wood while the stiffness allows super low action with the right fret dressing.  But later on in the mid eighties to mid nineties, some graphite necks had phenolic (aka Bakelite) fingerboards that were too stiff resulting in a brittle sounding bass (classic Bartolini soapbars and an SWR amp help tame things a bit).  Likewise, some suffered from fingerboards that weren't stiff enough due to not mixing the phenolic resin properly and some necks became bowed.  Modulus were notorious for this with the necks they made for Musicman and Alembic as well as their own instruments, but Status experienced issues with one mix of resin briefly in the mid nineties as well.

[LukeFRC]

12 hours ago, funkle said:

Thanks @Owen

 

Yes, the ACG is flat, Alan was clear that the design was clean and clear and flat when I spoke to him as well. I really like the ACG EQ-01. 
 

What I’m not sure about is whether the Wal preamp is flat or not. I might have not made that clear in the last post; apologies; it was rather long…

There is audio similarity between John East's uni-pre and the ACG EQ-01 pre, there's something in both preamps which is a brilliant clean, clear and lovely sounding... it's one of the nicest preamp out there by my book, I loved the ACG in my streamer and the Uni-pre has transformed my Lakland...  There was something on some really geeky audio forum I heard where they were comparing their bass passive into a load of high end preamps... and they threw the recording with the Uni-pre ... and a few people commented that it sounded as good (if not better) than some of those fancy preamps...

However it does not sound like, say a Sadowsky preamp which feels less polished and to my cloth ears at least the Wal's I have tried preamp were closer to this kinda sound. My theory of the LPF Wal sound is something todo with a slightly more primitive preamp than ACG, and also something about how the resonant peak at the cut off point gives some kind of phase or group delay around that point making it sound rich and almost like a very specific slight chorusy thing going on. My ACG equipped Streamer in recordings had a similar thing going on if I boosted both resonant peaks to the righht amount... but interestingly I didn't notice it when playing and it was only when recorded I noticed it.  

Be interesting to see how the Lusithand does - my guess is it will be closer because it's more likely to be a closer electronically, and not being dismissive on whoever makes them, but John and Alan knew what they were doing when they designed the ACG pre and designed something lovely to fit that need, using all of their combined skills... and they probably went beyond the Wal preamp in some ways...

Edited March 11, 2022 by LukeFRC

[funkle]

Agree @LukeFRC, spot on in all respects.
 

I especially noticed the chorusy effect on the Wal when playing with the filters and boosting resonance. 

[NickA]

16 hours ago, Kiwi said:

Later Wal necks also have a secret laminate of graphite under the fingerboard

They dropped that a long time ago.  You might have to go back to the pro bass to find a carbon layer.

 

The resonant peak on a Wal is a fixed amount of extra Q from the pull switch.  As the acg has an infinitely variable Q, it should be possible to exactly match the Wal. 

 

Still, I hardly ever use the pull switches on my Wals ( except when messing about) and can still get that "chorus like" effect.  I think that without the pull switch out, the filter is just a regular 2 pole LP fillter.  So I guess it's the phase difference between the two pickups that makes that sound. Bear in mind that a lot of those classic 80s Wal sounds were played through a chorus or phaser, so not all the bass.

Edited March 11, 2022 by NickA

[funkle]

Ok, I shot some audio and video, not my best, but it's getting put together as I remind myself how to video edit and upload to Youtube. Will post ASAP

 

The recordings are interesting. There is something of the Wal about it, a bit, and it sounds great in it own right. Very clean. The pickups I think are faithful to the system they have been installed in...I have been wavering here but am going to leave them in place for now. (I have spoken to Aaron Armstrong about custom wind Wal style multicoils and have that there as a backup if need be.)

 

It's a perhaps surprising conclusion, but I actually think my next port of call is to change the neck. I've been considering this carefully as I explore options, and I give you below an interesting quote which helped me firm up my own thoughts. This is from Luthier's Roundtable in Bass Gear Magazine back from 2011 (Tone Primer section) about necks:

Even though the body makes up most of an instrument's mass, neck materials and construction are important to tone. Some builders feel a single piece of wood is best, while others take the laminate approach. Some feel that reinforcing the neck with a stiff, light material like graphite improves tone, while others believe the best approach is to make the entire neck out of alternative material. Everyone agrees, though, the neck must be strong enough to withstand string tension. "Laminated necks are more stable," says Bob Mick, but " in general, a heftier neck gives better tone."

Ken Smith believes graphite reinforcement evens out a neck's response, while Roger Sadowsky prefers unreinforced, one-piece flatsawn maple necks to laminate construction. "Every few years I make a batch of graphite-reinforced necks just to remind my self it doesn't make much difference, says Sadowsky." They still get acoustic dead spots, and they're not significantly stiffer than our unreinforced necks. However, the fingerboard wood is a significant factor in the sound. It's easier for me to hear the difference between maple and rosewood fingerboard than between an alder and ash body.

 

Garry Willis avoids graphite reinforcement for a different reason: It raises the neck's resonant frequency, and he prefers lower-frequency resonance. Still some feel graphite (a.k.a carbon fiber) makes the ideal material. Rich Lasner says," A graphite neck eliminates sympathetic vibrations that either cancel or favor notes, because the neck's resonant frequency is above the range of the instrument's fundamental. The idea is to give the truest fundamental tone possible, and because of the material's greater stiffness, the notes sustain longer."

 

I'm going make a bet that another key ingredient here is the stiffness of the neck raising the resonant frequency enough to give the sound a significant boost in the mids, giving at least some of the Wal 'punch'. That, plus rosewood or ebony boards, is part of the 'recipe'. It's testable, so let's do it. (As an aside, I note Paul Hermann flat out refuses to do maple fretboards on custom Wal orders, though Pete Stevens did do some during his time. I wonder if this is because it messes with the Wal recipe too much? Ah well, speculative....)

 

I'm going to take some measurements of the neck - it's quite deep as well as having the slightly odd V shape - I would like to try and get as close as I can to the same neck stiffness whilst trying to make it perhaps a touch comfier. That may take some workings out about neck dimensions/volume.

 

I've been talking to @Andyjr1515 about a neck and he's game. I'm going to get a quote from Chris McIntyre too.

 

At this point, I may need to sell some stuff to fund the ongoing experimentation. You may see me in the classifieds more soon.

 

 

Since I have the Lusithand preamp in hand, I will install that next + record clips whilst sorting out a new neck and then waiting for it to arrive. A new neck is likely to take a few months.   

Edited March 15, 2022 by funkle

[funkle]

Another interesting Luthier's Roundtable on neck stiffness. Great side discussion on headstock shapes/size/stiffness/mass and dead spots. 

 

https://www.bassgearmag.com/luthiers-round-table-5/

Edited March 15, 2022 by funkle

[NickA]

The route from bridge to nut contains a lot more neck than body...stands to reason that it makes more difference.  The neck joint is also important as it's potentially lossy (pedants may also claim the impedance mismatch from neck wood to body wood will change the acoustic qualities).

[Kiwi]

13 hours ago, funkle said:

I'm going make a bet that another key ingredient here is the stiffness of the neck raising the resonant frequency enough to give the sound a significant boost in the mids, giving at least some of the Wal 'punch'. That, plus rosewood or ebony boards, is part of the 'recipe'. It's testable, so let's do it. (As an aside, I note Paul Hermann flat out refuses to do maple fretboards on custom Wal orders, though Pete Stevens did do some during his time. I wonder if this is because it messes with the Wal recipe too much? Ah well, speculative....)

I'd suggest stiffness of the fingerboard plus enough softer wood in the neck to dampen undesirable frequencies without so much it compromises structural rigidity.  In terms of wood anything other than ebony would be a compromise.  But Richlite might work as well and be both potentially cheaper and more convenient than faffing with phenolic resin.

For the laminates you'll almost certainly need some maple in there but there's always a risk that hard maple will be too stiff and dominate things.  Flamed maple laminated in a wenge neck (used often by AGC and Sei amongst others) sound fabulous to me but the wenge can make the upper mids sound a bit boxy which might take you away from the Wal sound a little.  So probably following Yamaha's recipe of 3x maple and 2x mahogany - something they've employed for well over 40 years in both basses and guitars, might be the way forward. 

 

You could also experiment with a 2mm graphite laminate under the fingerboard if you can, to see what impact it has on overall stiffness. It's got a little bit of flex in longer, narrower lengths but is very rigid across narrow widths and it's not prohibitively expensive to buy it in sheets anyway.  I've been making control panel and trem plates from it recently and it's possible to use woodworking tools on it if I take it easy.

[LukeFRC]

2 hours ago, Kiwi said:

So probably following Yamaha's recipe of 3x maple and 2x mahogany - something they've employed for well over 40 years in both basses and guitars, might be the way forward. 

I just had the thought that a yamaha bb might make a good platform for experimentation as there are some similarities in neck construction… maybe.

 

[funkle]

Thanks @Kiwi.

 

I’m going to stick exactly to the Wal (and Yamaha) recipe. 
 

Rosewood fretboard, 5 piece maple and mahogany laminate neck, no graphite (it was present only in some of the Pro models), and match dimensions/volume of neck and headstock as closely as I can whilst making it more comfortable and look better. 

[funkle]

4 hours ago, LukeFRC said:

I just had the thought that a yamaha bb might make a good platform for experimentation as there are some similarities in neck construction… maybe.

 

I explored that idea earlier in the thread. I have since very nearly bought one, because it is basically ideal. The TRBX504 and 304 have exactly the right body woods, neck construction/fretboard, already have routed out control and battery cavities, and the like. They have a Jazz width nut for comfort and decent hardware (though not amazing). They will be made well. 
 

You must be psychic @LukeFRCas I have been seriously been considering buying one secondhand in the last few days; would save me the cost of making another neck and would be cheaper. 
 

My only reservation has been routing out bigger holes for pickups in different spots to where the pickups currently are and then figuring out how to cover it. Routing out is expensive.
 

Also using a Fender test bed means parts and swaps are pretty easy. 
 

But I have definitely been considering it…

Edited March 16, 2022 by funkle

[Andyjr1515]

I think the BB option is a great one to test out your thoughts about the impact of the neck construction on the sound you are trying to emulate.

 

 

[Andyjr1515]

2 hours ago, funkle said:

My only reservation has been routing out bigger holes for pickups in different spots to where the pickups currently are and then figuring out how to cover it. Routing out is expensive.
 

In terms of pickup routs, I don't use a router except for tidying up the lower part of the sides and bottom of the chamber...and that is unseen and optional.  I use a forstner bit and sharp chisel.  I can post an extract from one of my build threads if that helps.

[funkle]

1 hour ago, Andyjr1515 said:

In terms of pickup routs, I don't use a router except for tidying up the lower part of the sides and bottom of the chamber...and that is unseen and optional.  I use a forstner bit and sharp chisel.  I can post an extract from one of my build threads if that helps.

Yes please!

[Andyjr1515]

44 minutes ago, funkle said:

Yes please!

 

Here's an extract from the build of @Jus Lukin's headless with three Sims Superquads.   As I say above, the use of the router at the end is optional - you can use the Forstner to the full depth of the pickup and leave the 'spike holes' there...no one's going to see them.

 

This one has just 4 corners for each pickup, but it is just the same principle for, say, a lugged Jazz pickup - you just use appropriate diameter drills for the corners and lug ends.

 

I use this method for all of my pickup chambers - I flipping detest routers!

 

 

The pickup chambers.  I use the same method - which is basically mark out, hog out, chisel out and then use a captive bearing router bit to tidy it up and reach the final depth.  

With pickup chambers, the first thing I do is check the radius of the corners and use a bradpoint 1mm larger (to allow for the 0.5mm clearance all round) and drill the corners:

 

Then I hog out as close to the marked line as I can with as large a Forstner as I can:

Then I chisel 10mm or so down, right up to the outline:

 

Finally, I use a flush bearing router bit, that will be fully captive, to deepen the chamber to final depth:

 

 

 

[Andyjr1515]

If you do use this method, the key is a VERY sharp chisel and, using a mallet or light hammer, removing the 'waves' a teeny bit at a time from the peak to the base. 

 

[Owen]

4 minutes ago, Andyjr1515 said:

If you do use this method, the key is a VERY sharp chisel and, using a mallet or light hammer, removing the 'waves' a teeny bit at a time from the peak to the base. 

 

It all seems so easy

[funkle]

Ok, video. Enjoy!

 

I swear to goodness this took me ages to figure out how to do, and it's so long I had to do a ton of editing. On the plus side, I've learned a lot and can now make a video in Reaper. 

 

I'm still adding time stamps in description, please be patient...

 

 

@NickA I'm not sure I'll have time today to upload the screenshots I promised of frequency response. Will get to it!